Compositions for controlled crystal growth and methods of production thereof

Abstract

Novel build material compositions, systems, and methods of making the same are described herein. Biocementitious techniques are described that monitor and regulate environmental and process control during manufacture of biocementitious products. Construction materials having excellent properties, such as increased compressive strength, can be manufactured using the biocement technology. In some cases, the rate of biocement formation within different planar sections of build material is selectively controlled by applying and adjusting temperature, pH, and humidity. For example, a rate at which planar sections of the build material, including a non-preferred surface (or a surface to which a cementitious solution is applied), form biocement can be slower than other planar sections of the build material at least a certain threshold distance from the non-preferred surface.

Description

CLAIM OF PRIORITY

[0001] This application claims the benefit of and priority to U.S. Provisional Application 63 / 488,397, filed March 3, 2023, which is incorporated by reference herein in its entirety. BACKGROUND

[0002] Compared to traditional building materials and concrete, bio-cement technology offers cost-effective high-strength building materials, structural materials, and concrete that can have substantially reduced carbon footprint. As such, improved bio-cement compositions and processes can facilitate the replacement of traditional building materials and concrete with bio-cement products. SUMMARY

[0003] Bio-cement technology utilizes microorganisms to improve the mechanical and structural properties of construction materials. In some cases, through microbial-induced calcium carbonate precipitation (MICP), microorganisms can react with chemical components to generate minerals in the form of organic-inorganic compounds that act as binders within construction materials. In some cases, environmental and process controls can be utilized to ensure that the surface of a construction material (or planar sections abutting the outer surface) forms bio-cement at a slower rate than other portions or planar sections of the construction material when a cementitious solution feed containing a cementitious agent is applied to the surface of the construction material (e.g., using a fluid delivery system to apply the cementitious solution to the surface of the construction material). The technical benefits of reducing the rate of bio-cement formation within one or more planar sections of a construction material proximate to or abutting a surface to which a cementitious solution is applied (e.g., planar sections constituting the top 1 cm of the construction material) can reduce plugging-related issues, can reduce the overall cost of manufacturing the construction material, can increase the compressive strength of the construction material, and can reduce manufacturing variability in the properties of the construction material.

[0004] In some embodiments, the rate of bio-cement formation within different planar sections of a construction material is selectively controlled by applying and adjusting temperature, pH, and / or humidity during the manufacturing of the construction material. In one example, planar sections of the construction material that include a non-preferred surface (or a surface to which a cementitious solution is applied) form bio-cement at a slower rate than other planar sections of the construction material that are at least a certain threshold distance from the non-preferred surface.

[0005] In some embodiments, the temperature of the construction material, both prior to and during biocementation, and the temperature of the feed solution fed to the construction material, can be independently varied during the manufacture of the construction material. In one example, the temperature of the feed solution can be lower than the temperature of the construction material during the biocementation process stage. In another example, the temperature of the feed solution can be initially lower than the temperature of the construction material during a first time period, and then increased during a second time period after the first time period, during the biocementation stage. In another example, the temperature of the feed solution can be lower than the temperature of the construction material during a first time period, and then increased to be higher than the temperature of the construction material during a second time period after the first time period. During the formation of the microbial calcite precipitate within the construction material, the temperature of the construction material and the humidity of the environment in which the construction material is located can be adjusted to improve the resulting compressive strength of the construction material.

[0006] In some embodiments, a biocement technology is provided that monitors and adjusts the environment and process controls to ensure that the rate of biocement formation is slower for planar sections of the construction material that are proximate to or abut the non-preferred surface (or surface to which the cementitious solution is applied) compared to other planar sections of the construction material that are distal or do not abut the non-preferred surface. In one example, the rate of biocement formation for planar sections that constitute the top 1 cm of the construction material is at least 20% to 50% slower than the rate of biocement formation for one or more other planar sections of the construction material (e.g., planar sections that constitute the bottom 10 cm of the construction material). The temperature of the construction material and the cementitious solution can be varied during the manufacture of the construction material to reduce the rate of biocement formation for planar sections that are proximate to or abut the non-preferred surface.

[0007] According to some embodiments, technical benefits of the compositions and methods of producing controlled crystal growth disclosed herein include reduced manufacturing time, increased construction material throughput, increased flexural strength, and increased compressive strength of the construction material.

[0008] This Summary is provided to introduce some aspects of the disclosed technology in a simplified form that are further described below in the DETAILED DESCRIPTION. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. Furthermore, the claimed subject matter is not limited to implementations that solve any or all of the disadvantages noted in any part of this disclosure. BRIEF DESCRIPTION OF DRAWINGS

[0009] Like-numbered elements can refer to common components across different figures.

[0010] FIG. 1A An exemplary template for manufacturing a construction material is illustrated.

[0011] FIG. 1B One embodiment of a cross-sectional view of a construction material is depicted.

[0012] FIG. 1C One embodiment of a cross-sectional view of a construction material is depicted. FIG. 1B

[0013] FIG. 1D One embodiment of a cross-sectional view of a construction material is depicted. FIG. 1B

[0014] FIG. 1E One embodiment of aggregate particles within a construction material prior to compression is depicted. FIG. 1D

[0015] FIG. 1F One embodiment of aggregate particles within a construction material after compression of the aggregate particles is depicted. FIG. 1D

[0016] FIG. 1G One embodiment illustrating experimental results showing the average compressive strength of a construction material over a range of construction material wet green density is depicted.

[0017] FIG. 1H One embodiment illustrating a plot showing the percent of total pore volume of a construction material versus pore diameter is depicted.

[0018] FIG. 1I One embodiment illustrating experimental results showing the average change in electrical conductivity of a construction material over a range of construction material average dry green density is depicted.

[0019] FIG. 1J One embodiment illustrating a plot showing the total slice porosity at the location of horizontal slices of a non-preferred surface of a construction material is depicted.

[0020] FIG. 1K One embodiment illustrating experimental results showing the total open porosity of a construction material versus the number of slices is depicted.

[0021] FIG. 1L One embodiment of a construction material body including aggregate particles bound together using calcium carbonate is depicted.

[0022] FIG. 1M One embodiment illustrating experimental results showing the compressive strength of a construction material versus wet density and the compressive strength versus dry density is depicted.

[0023] ​​​​FIG. 1N One embodiment depicting experimental results showing the relationship of the percent of calcium carbonate of a build material to wet density and the percent of calcium carbonate to dry density.

[0024] FIG. 2A to FIG. 2B An SEM image of a top surface layer of an exemplary build material is depicted. FIG. 2B An SEM image of a top surface layer of an exemplary build material is depicted. FIG. 2A An enlarged view of a certain area within is shown.

[0025] FIG. 3A to FIG. 3B An SEM image of a top surface layer of an exemplary build material is depicted. FIG. 3B An SEM image of a top surface layer of an exemplary build material is depicted. FIG. 3A An enlarged view of a certain area within is shown.

[0026] FIG. 4A to FIG. 4B An SEM image of a top surface layer of an exemplary build material is depicted. FIG. 4B An SEM image of a top surface layer of an exemplary build material is depicted. FIG. 4A An enlarged view of a certain area within is shown.

[0027] FIG. 5A One embodiment depicting a system for manufacturing a build material using one or more biocementation processes.

[0028] FIG. 5B A flowchart depicting one embodiment describing a process for producing a build material is depicted.

[0029] FIG. 5C A flowchart depicting an alternative embodiment describing a process for producing a build material is depicted.

[0030] FIG. 5D A flowchart depicting an alternative embodiment describing a process for producing a build material is depicted. DETAILED DESCRIPTION

[0031] As used herein, the term one or more "build materials" generally refers to an article of manufacture comprising elements or subassemblies that are bound together by a linker (e.g., a cementitious linker) or bridge having adhesive properties. In some cases, the linker or bridge within a build material comprises a binding agent, such as calcium carbonate. A build material can comprise a single physical object having a particular shape that is incorporated into, for example, a construct, structure, or article of manufacture.

[0032] Some construction materials can include bio-cementitious products. Examples of bio-cementitious products include, but are not limited to, articles made from bio-concrete, bio-cement coated aggregates, and the like. As used herein, the term “bio-cement” generally refers to any binding agent that can be produced by a biological mechanism (e.g., an enzymatic process) that adheres or encapsulates particles of a solid material (e.g., aggregate particles). The binding agent can directly connect two or more aggregate particles, or can indirectly connect two or more aggregate particles through one or more connectors or bridges within the construction material. The one or more connectors or bridges within the construction material can provide structural support to the construction material, and / or provide a structural connection between at least two aggregate particles of a plurality of aggregate particles within the construction material. In some cases, the aggregate particles include sand, gravel, and / or crushed stone. The shape of the aggregate particles can be classified as polygonal, semi-polygonal, near-circular, or circular. Examples of bio-cement include the binding of calcium carbonate with particles of a pre-existing solid material that is formed from microbial-induced carbonate precipitation (MICP). Other examples include bio-sintered metal carbonates such as, but not limited to, calcium carbonate, magnesium carbonate, barium carbonate, or strontium carbonate.

[0033] As used herein, the term “bridged calcium carbonate” generally refers to calcium carbonate that is connected to and / or binds together at least two portions, such as aggregate particles. The bridged calcium carbonate, together with the at least two portions, provides a continuous piece that includes the at least two portions and the bridged calcium carbonate. The calcium carbonate can be a solid, such as a precipitate. The calcium carbonate can be formed from the reaction of calcium ions with carbonate ions in an aqueous solution, where the resulting calcium carbonate is integrated into a bulk composite material that includes the calcium carbonate and the aggregate particles.

[0034] As used herein, the term “non-bridged calcium carbonate” generally refers to calcium carbonate that is not connected to or binds together at least two portions, such as aggregate particles. The non-bridged calcium carbonate can be a precipitate that is connected to only one portion, such as an aggregate particle, or a precipitate that is not connected to any aggregate particles. The non-bridged calcium carbonate can be bound to at most one portion.

[0035] As used herein, the terms “aggregate” or “aggregate particles” can be used interchangeably and generally refer to any type of particulate matter that can be bound together by a bio-cementitious bond or bridge to form a larger particle or consolidated solid. Non-limiting examples of aggregates include sand, gravel, mine tailings, or combinations thereof, and the like.

[0036] As used herein, the term "cementitious agent" generally refers to any combination of growth nutrients or starting materials that, when combined and reacted, produce a binding agent through biological mechanisms. For example, an enzyme (or an organism containing an enzyme) can cause the enzymatic formation of a biological cement, such as calcium carbonate, that binds together adjacent aggregate particles. For example, the cementitious agent in a urea hydrolysis-based biological cementation system can include urea (or another suitable nitrogen source), a soluble calcium source (e.g., calcium chloride, calcium acetate, calcium phosphate, calcium lactate, calcium nitrate, etc.), nutrients that promote urease activity (which can vary depending on whether a pure enzyme or urease-producing cells are used), and urease (to form and precipitate calcium carbonate biological cement). In a calcium carbonate-based biological sintering biological cementation system, an example of a biological cementitious agent can include calcium carbonate, nutrients that promote enzymatic acid production, and an acidogenic enzyme (to produce an acid that dissolves calcium carbonate). The biological cementitious agent of such a system can additionally include a second set of nutrients and a second enzyme that collectively promote a decrease in pH that causes calcium carbonate to re-precipitate to form biological cement.

[0037] As used herein, the terms "produce," "production," and "producing" with respect to calcium carbonate, in the presence of an enzyme or organism, refer to the biological reaction by the enzyme or organism to create conditions for the formation of calcium carbonate from starting materials such as calcium ions, carbonate ions, or other possible chemical entities. For example, an enzyme that produces carbonate ions or calcium ions can be referred to as an enzyme that produces calcium carbonate. An enzyme that causes a change in pH to cause calcium carbonate to precipitate can also be referred to as a calcium carbonate-producing enzyme.

[0038] As used herein, the term microbial-induced calcium carbonate precipitation (MICP) (also referred to as microbial-induced calcite precipitation) generally refers to the production of calcium carbonate using at least one enzyme or organism. The at least one enzyme or organism can form calcium ions or carbonate ions, or can change the pH of the environment to precipitate calcium carbonate.

[0039] As used herein, "RPM" and "rpm" are used as units of instantaneous rotational speed, equivalent to revolutions per minute when the speed is maintained for a full minute (i.e., a duty cycle of 100%).

[0040] Construction material The construction materials described herein can take a variety of different forms and shapes. The exemplary construction materials, such as a unit or brick having a top surface, four vertical side surfaces, and a bottom surface, can be used to illustrate a number of features of the disclosed embodiments. However, the construction materials are not limited to brick forms. For example, another exemplary construction material can be a circular tile having a top surface, a vertical circular side surface, and a bottom.

[0041] Structural bio-cement-based concretes (e.g., bio-cement bricks) can rely on the formation of interconnecting calcium carbonate crystals that bind surrounding aggregate particles together. While bio-cement formation can be the product of microbial-induced calcite formation, MICP can produce calcium carbonate that is not associated with the formation of structural bio-cement (e.g., isolated calcium carbonate crystals that are not bound to more than one aggregate particle).

[0042] In some cases, the connected bio-cement bridges can be formed as homogenously as possible throughout the aggregate matrix / network, binding adjacent aggregate particles to ensure structural integrity of the entire product (e.g., one region can not be significantly stronger or weaker than another region). In some cases, structural integrity of the product can be achieved by distributing MICP throughout the body of the bio-cement-based concrete such that the concentration or weight percent of bridged calcium carbonate, or the calcium-to-silicon ratio, at different cross-sections of the product differ from one another by no more than 70%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, or 10%.

[0043] When MICP reactions form non-connected, isolated, non-bridging calcium carbonate crystals, these crystals can fill the pore space between aggregate particles, preventing additional calcium carbonate formation required for structural bridging, thus referred to as plugging. Furthermore, when a solution containing calcium and urea is applied directionally to an aggregate matrix, if bio-cement is produced at a faster rate at the surface of the solution application (non-preferred surface), the bio-cement formation or plugging-induced reduction in pore space can prevent bio-cement from forming deeper within the unit / bio-cement-based concrete. In some cases, when a unit / bio-cement-based concrete has difficulty achieving homogenous bio-cementation (e.g., due to less variation in the degree of MICP formation within the unit body), another goal can be to produce a higher concentration of bio-cement at the surface farthest from the solution application (preferred surface). When the pore space is reduced to the point that the applied solution can no longer enter the interior of the unit, non-structural, non-connected calcium carbonate crystals can form that are concentrated at the surface of the material. This phenomenon is described as “collapse,” indicating the formation of calcium carbonate on the surface of the unit. In practice, preventing collapse is desirable to reduce the cost of the direct material, while improving product performance, consistency, and manufacturing repeatability. Early formation of collapse is an indication that bio-cement or plugging is occurring first at the non-preferred surface (or solution application surface).

[0044] In some embodiments, collapse can be prevented or reduced in practice if (a) the applied solution does not contain particulate matter that can plug aggregate pore space in a non-structural manner, and / or (b) the rate of cementation at the non-preferred surface (or solution application surface) is not faster (or slower), or is below a rate threshold.

[0045] Regarding (a): Upon seeking conditions that can reduce the formation of non-bridging calcium carbonate in a collapse, the following conditions were identified: filtration of the feed solution to prevent inert materials (such as loose aggregate and / or plant matter) from circulating within the provided calcium and / or urea solutions. However, while the feed solution can be practically non-sterile, microbial contamination in the aggregate matrix can contaminate the solution in the form of free-floating cells. When MICP occurs in the solution outside but around the aggregate network, discrete, detached, non-connected calcium carbonate crystals are formed, which can also produce particulate matter within the solution outside the aggregate. Thus, it is also beneficial to inhibit / reduce biological activity (production of enzymes or organisms) within the solution, so that MICP occurs primarily only within the aggregate matrix where bio-cement formation is desired. In practice, biological activity can be successfully inhibited by applying ultraviolet radiation treatment and / or introducing ozone and / or blowing fresh air into the solution on top of the aggregate network.

[0046] Regarding (b): One option is to use environmental and process controls to ensure that non-preferred surfaces do not form bio-cement faster than preferred surfaces. In some cases, non-preferred surfaces are on the top surface, as the feed solution can be applied by a fluid delivery system that relies on gravity. The rate of bio-cement formation can be associated with the metabolic activity of the microorganisms or enzymes and their rate of reproduction (e.g., fermentation, doubling rate). Temperature, nutrient availability, and respiration can affect the biological activity of the microorganisms or enzymes. Thus, options include (a) controlling the temperature of the process so that the temperature at or near the non-preferred surface is not higher (or lower) than the temperature at or near the preferred surface, which can be controlled by ensuring that the aggregate matrix is hotter than the solution applied to the non-preferred surface; (b) complete dissolution of nutrients in the feed solution so that the nutrients can be homogeneously dispersed throughout the unit; and / or (c) for anaerobic or facultative anaerobic microorganisms used in the MICP process, ensuring sufficient oxygen for microbial respiration, which can be achieved by regular aeration in a closed system or natural ventilation in an open system.

[0047] Described herein are construction materials comprising a plurality of aggregate particles, bridging calcium carbonate crystals between at least two members of the plurality of aggregate particles, non-bridging calcium carbonate crystals, and at least one organism or enzyme that produces at least some of the bridging calcium carbonate crystals. The construction material can comprise at least one surface and a body enclosed by the at least one surface. The construction material can comprise: (i) a first average concentration of non-bridging calcium carbonate crystals at or near the at least one surface that is not greater than a second average concentration of bridging calcium carbonate crystals at or near the at least one surface, or (ii) the second average concentration differs from a third average concentration of bridging calcium carbonate crystals at or near a cross-section of the body by no more than 70%.

[0048] In some embodiments, the build material can include: (i) a first average concentration of non-bridging calcium carbonate crystals at or near the at least one surface that is not greater than a second average concentration of bridging calcium carbonate crystals at or near the at least one surface, or (ii) the second average concentration differs from a third average concentration of bridging calcium carbonate crystals at or near a cross-section of the body by no more than 70%.

[0049] In some embodiments, the first average concentration of non-bridging calcium carbonate crystals at or near the at least one surface is not greater than the second average concentration of bridging calcium carbonate crystals at or near the at least one surface. In some embodiments, the first average concentration is not greater than the second average concentration. In some embodiments, the first average concentration is not greater than 99%, 95%, 90%, 85%, 80%, 75%, 70%, 65%, or 60% of the second average concentration. In some embodiments, the first average concentration is about 30% to about 100% of the second average concentration, about 35% to about 95% of the second average concentration, about 40% to about 90% of the second average concentration, about 45% to about 85% of the second average concentration, about 50% to about 80% of the second average concentration, or about 55% to about 75% of the second average concentration. In some embodiments, the first average concentration is about equal to the second average concentration. In some embodiments, the first average concentration is not greater than 170%, 165%, 160%, 155%, 150%, 145%, 140%, 135%, 130%, 125%, 120%, 115%, 110%, or 105% of the second average concentration.

[0050] In some embodiments, the second average concentration differs from the third average concentration by no more than 50%. In some embodiments, the second average concentration differs from the third average concentration by no more than 69%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, or 10%. In some embodiments, the second average concentration differs from the third average concentration by about 10% to about 70%, about 15% to about 65%, about 20% to about 60%, about 25% to about 55%, about 30% to about 50%, or about 35% to about 45%. In some embodiments, the second average concentration differs from the third average concentration by no more than 50%. In some embodiments, the second average concentration differs from the third average concentration by no more than 69%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, or 10%.

[0051] In some embodiments, a construct material as described herein, wherein the at least one surface comprises a first surface and a second surface, and wherein the first average at or near the first surface differs from the first average at or near the second surface by no more than 50%. In some embodiments, the first average concentration at or near the first surface differs from the first average concentration at or near the second surface by no more than 49%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, or 10%.

[0052] Described herein is a construct material comprising: (a) a first surface; (b) a second surface generally opposite the first surface; (c) one or more walls between and connecting the first surface and the second surface; and (d) a body enclosed by the first surface, the second surface, and the one or more walls; (e) a plurality of aggregate particles; (f) bridged calcium carbonate crystals between at least two members of the plurality of aggregate particles; (g) non-bridged calcium carbonate crystals; and (h) at least one organism or enzyme that produces at least some of the bridged calcium carbonate crystals, wherein a first average concentration of the non-bridged calcium carbonate crystals on the first surface is at least about 10% higher than a second average concentration of the non-bridged calcium carbonate crystals on the second surface.

[0053] In some embodiments, the first average concentration is at least about 15%, at least about 20%, at least about 25%, at least about 30%, at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at least about 65%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, or at least about 100% higher than the second average concentration. In some embodiments, the first average concentration is at least about 10% higher than a third average concentration of non-bridging calcium carbonate crystals at or near the cross-section of the body. In some embodiments, the first average concentration is at least about 15%, at least about 20%, at least about 25%, at least about 30%, at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at least about 65%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, or at least about 100% higher than the third average concentration. In some embodiments, (i) the first average concentration is higher than a fourth average concentration of bridging calcium carbonate crystals at or near the first surface, or (ii) the fourth average concentration is no more than 70% different than a fifth average concentration of bridging calcium carbonate crystals at or near the cross-section of the body. In some embodiments, the fourth average concentration is no more than 69%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, or 10% different than the fifth average concentration. In some embodiments, the at least one organism or enzyme comprises urease or cells of a urease-producing microorganism. In some embodiments, the at least one organism or enzyme comprises acid-producing enzyme or cells of an acid-producing microorganism. In some embodiments, the at least one organism or enzyme comprises carbonic anhydrase or cells of a carbonic anhydrase-producing microorganism. In some embodiments, the at least one organism or enzyme comprises a urea-producing microorganism. In some embodiments, the average compressive strength of the build material is at least about 1,500 pounds per square inch (psi).In some embodiments, the average compressive strength is at least about 1,500 psi, 1,600 psi, 1,700 psi, 1,800 psi, 1,900 psi, 2,000 psi, 2,200 psi, 2,400 psi, 2,600 psi, 2,800 psi, 2,900 psi, 3,000 psi, 3,200 psi, 3,400 psi, 3,600 psi, 3,800 psi, 4,000 psi, 4,200 psi, 4,400 psi, 4,600 psi, 4,800 psi, 5,000 psi, 5,200 psi, 5,400 psi, 5,600 psi, 5,800 psi, 6,000 psi, 6,200 psi, 6,400 psi, 6,600 psi, or 6,800 psi.

[0054] Weight percent of calcium carbonate Described herein are construction materials comprising (a) a first surface; (b) a second surface generally opposite the first surface; (c) one or more walls between and connecting the first surface and the second surface; (d) a body enclosed by the first surface, the second surface, and the one or more walls, the body comprising a plurality of aggregate particles; (e) calcium carbonate; and (f) at least one organism or enzyme that produces at least some of the calcium carbonate formed between at least two members of the plurality of aggregate particles, wherein a first average weight percent of the calcium carbonate on the first surface differs by no more than 50% from a second average weight percent of the calcium carbonate on the second surface.

[0055] In some embodiments, a first average weight percent of the calcium carbonate on a cross-section of the body differs by no more than 50% from a third average weight percent. In some embodiments, the first average weight percent differs by no more than 49%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, or 10% from the second average weight percent. In some embodiments, the first average weight percent differs by no more than 49%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, or 10% from the third average weight percent.

[0056] Porosity Described herein are construction materials comprising (a) a first surface; (b) a second surface generally opposite the first surface; (c) one or more walls between and connecting the first surface and the second surface; (d) a body enclosed by the first surface, the second surface, and the one or more walls, the body comprising a plurality of aggregate particles; (e) calcium carbonate; and (f) at least one organism or enzyme that produces at least some of the calcium carbonate formed between at least two members of the plurality of aggregate particles, wherein a first average porosity of the construction material is from 15% to 50%.

[0057] In some embodiments, porosity can be measured by collecting X-ray computed tomography data from two-dimensional slices to produce a three-dimensional image of the sample, thereby calculating the porosity of the sample. In some embodiments, the porosity distribution can be determined by mercury intrusion porosimetry (MIP) analysis, which can provide information about the size and distribution of pores present in the sample. In some embodiments, the porosity of a sample can be estimated by testing how much water the sample can absorb.

[0058] In some embodiments, the first average porosity on the first surface differs from the second average porosity on the second surface by no more than 50%. In some embodiments, the first average porosity differs from the second average porosity by no more than 49%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, or 10%.

[0059] In some embodiments, the first average porosity on the first surface differs from the second average porosity on the second surface by more than 50%. In some embodiments, the first average porosity differs from the second average porosity by more than 51%, 60%, 70%, 80%, 90%, 100%, 110%, 120%, 130%, 140%, 150%, 160%, 170%, 180%, 190%, 200%, or more.

[0060] In some embodiments, the first average porosity on the first surface differs from a third average porosity on a cross-section of the body by no more than 50%. In some embodiments, the first average porosity differs from the third average porosity by no more than 49%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, or 10%.

[0061] In some embodiments, the first average porosity on the first surface is more than 50% different than the third average porosity on the cross-section of the body. In some embodiments, the first average porosity is more than 51%, 60%, 70%, 80%, 90%, 100%, 110%, 120%, 130%, 140%, 150%, 160%, 170%, 180%, 190%, 200% or more different than the third average porosity.

[0062] In some embodiments, the first average porosity on the first surface is less than 50% of the second average porosity on the second surface. In some embodiments, the first average porosity is less than 49%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, or 5% of the second average porosity.

[0063] In some embodiments, the first average porosity on the first surface is less than 50% of the third average porosity on the cross-section of the body. In some embodiments, the first average porosity is less than 49%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, or 5% of the third average porosity.

[0064] In some embodiments, the first average porosity on the first surface is less than 50% of the third average porosity across the cross-section of the body, and the third average porosity is less than 50% of the second average porosity on the second surface. In some embodiments, the first average porosity is less than 49% of the third average porosity, and the third average porosity is less than 49%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, or 5% of the second average porosity. In some embodiments, the first average porosity is less than 45% of the third average porosity, and the third average porosity is less than 49%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, or 5% of the second average porosity. In some embodiments, the first average porosity is less than 40% of the third average porosity, and the third average porosity is less than 49%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, or 5% of the second average porosity. In some embodiments, the first average porosity is less than 35% of the third average porosity, and the third average porosity is less than 49%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, or 5% of the second average porosity. In some embodiments, the first average porosity is less than 30% of the third average porosity, and the third average porosity is less than 49%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, or 5% of the second average porosity. In some embodiments, the first average porosity is less than 25% of the third average porosity, and the third average porosity is less than 49%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, or 5% of the second average porosity. In some embodiments, the first average porosity is less than 20% of the third average porosity, and the third average porosity is less than 49%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, or 5% of the second average porosity. In some embodiments, the first average porosity is less than 15% of the third average porosity, and the third average porosity is less than 49%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, or 5% of the second average porosity. In some embodiments, the first average porosity is less than 10% of the third average porosity, and the third average porosity is less than 49%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, or 5% of the second average porosity. In some embodiments, the first average porosity is less than 5% of the third average porosity, and the third average porosity is less than 49%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, or 5% of the second average porosity.

[0065] Density Described herein are a construction material comprising (a) a first surface; (b) a second surface generally opposite the first surface; (c) one or more walls between and connecting the first surface and the second surface; (d) a body enclosed by the first surface, the second surface, and the one or more walls, the body comprising a plurality of aggregate particles; (e) calcium carbonate; and (f) at least one organism or enzyme that produces at least some of the calcium carbonate formed between at least two members of the plurality of aggregate particles, wherein: 1) the average green density of the construction material is from about 1.5 g / cc to about 2.5 g / cc, or 2) the average finished density of the construction material is from about 1.8 g / cc to about 2.7 g / cc, or 3) the average void percentage of the green density is from about 25% to about 46%, or 4) the average percentage of voids filled in the finished product (e.g., the average of the percentage of CaC03 produced) is from about 5% to about 25%, or 5) any combination thereof. As used herein, the unit “g / cc” generally refers to the unit gram per cubic centimeter (g / cm3), which is a unit of density. The void percentage within a portion of the construction material can correspond to the average porosity of the portion of the construction material.

[0066] As used herein, the term “green density” generally refers to the density of a construction material prior to sintering. The term “green density” can refer to a wet green density (which can include the density of a pressed unit at the time of pressing) or a dry green density (which can include the density of a pressed unit that has been fully dried).

[0067] As used herein, the term "green density" generally refers to the density of the green body prior to sintering. In some embodiments, the average green density is about 1.5 g / cc to about 1.8 g / cc, about 1.6 g / cc to about 1.9 g / cc, about 1.7 g / cc to about 2.0 g / cc, about 1.8 g / cc to about 2.1 g / cc, about 1.9 g / cc to about 2.2 g / cc, about 2.0 g / cc to about 2.3 g / cc, about 2.1 g / cc to about 2.4 g / cc. In some embodiments, the average green density is about 1.7 g / cc to about 2.0 g / cc. In some embodiments, the average green density is about 1.5 g / cc, 1.6 g / cc, 1.7 g / cc, 1.8 g / cc, 1.9 g / cc, 2.0 g / cc, 2.1 g / cc, 2.2 g / cc, 2.3 g / cc, or 2.4 g / cc. In some embodiments, the average green density is about 1.8 g / cc to about 1.9 g / cc, about 1.9 g / cc to about 2.0 g / cc, about 2.0 g / cc to about 2.1 g / cc, about 2.1 g / cc to about 2.2 g / cc, about 2.2 g / cc to about 2.3 g / cc, about 2.3 g / cc to about 2.4 g / cc, about 2.4 g / cc to about 2.5 g / cc, about 2.5 g / cc to about 2.6 g / cc, or about 2.6 g / cc to about 2.7 g / cc. In some embodiments, the average green density is about 2.0 g / cc to about 2.1 g / cc. In some embodiments, the average green density is about 1.8 g / cc, 1.9 g / cc, 2.0 g / cc, 2.1 g / cc, 2.2 g / cc, 2.3 g / cc, 2.4 g / cc, 2.5 g / cc, 2.6 g / cc, or 2.7 g / cc. In some embodiments, the average void percentage of the green density is about 25% to about 28%, about 28% to about 31%, about 31% to about 34%, about 34% to about 37%, about 37% to about 40%, about 40% to about 43%, or about 43% to about 46%. In some embodiments, the average void percentage of the green density is about 30% to about 42%. In some embodiments, the average void percentage of the green density is about 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%, 31%, 42%, 43%, 44%, 45%, 46%, or 47%. In some embodiments, the average percentage of CaC03 produced is about 5% to about 10%, about 10% to about 15%, about 15% to about 20%, or about 20% to about 25%.In some embodiments, the average of the percentage of CaC03 produced is from 10% to about 23%. In some embodiments, the average of the percentage of CaC03 produced is about 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, or 25%.

[0068] Homogeneity Described herein are construction materials comprising (a) a first surface; (b) a second surface generally opposite the first surface; (c) one or more walls between and connecting the first surface and the second surface; (d) a body enclosed by the first surface, the second surface, and the one or more walls, the body comprising a plurality of aggregate particles; (e) calcium carbonate; and (f) at least one organism or enzyme that produces at least some of the calcium carbonate formed between at least two members of the plurality of aggregate particles, wherein the homogeneity of the formed biocement is evaluated by a compressive strength curve from a top surface to a bottom surface, or by a percentage of a calcium carbonate distribution curve from a top surface to a bottom surface, or by comparing images produced by SEM / EDX (scanning electron microscopy with energy dispersive X-ray spectroscopy) to compressive strength of selected layers away from the top surface or the bottom surface.

[0069] In some embodiments, by comparing samples that pass or fail units based on compressive strength, the passing units comprise a higher percentage of calcium carbonate, and thus a higher percentage of biocement (or biogenic calcium carbonate). In some embodiments, the distribution of biocement in passing units is more homogenous or uniform (e.g., less variation between layers of different depths from the top surface) than the distribution of biocement in failing units. In some embodiments, the distribution of biocement is evaluated by percentage of calcium carbonate, or percentage of calcium carbonate produced, or percentage of voids after sintering. In some embodiments, the sintering temperature to produce a construction material of the present disclosure comprising biocement is lower than the sintering temperature to produce a traditional construction material that does not substantially comprise biocement (e.g., a construction material comprising no more than 5%, 4%, 3%, 2%, or 1% of biocement in the form of calcium carbonate).

[0070] Materials / Compositions Construction materials according to the present disclosure can be substantially homogenous. In some embodiments, construction materials obtained according to the disclosure and methods herein can be substantially continuous. In some embodiments, construction materials are substantially homogenous. In some embodiments, construction materials are substantially porous.

[0071] The plurality of aggregate particles can include any type of natural rock or stone, glass, glass fibers, wood, biomass, paper, metal, plastic, polymer, rubber, rubber imitation, vinyl, mineral, rock or stone imitation, recycled material (such as recycled brick, recycled concrete, recycled stone), mine tailings and mining residuals, washer waste, and / or combinations thereof. The plurality of aggregate particles can be of any size, including a mixture of different sizes, so long as the size of the aggregate is less than the resulting structure. The plurality of aggregate particles can include particles of 10 mm or less, 5 mm or less, 1 mm or less, 0.5 mm or less, or combinations thereof. The mesh size can be determined as desired, including but not limited to very fine particles (any number between 32 and 300 standard mesh, including the end values), fine particles (any number between 10 and 32 standard mesh, including the end values), medium particles (less than 10 standard mesh, including all mesh numbers therein), and coarse particles (particles greater than or equal to 2 mm), and combinations thereof. The particles can have almost any shape, including, for example, round or circular, oval, spherical (grade S), square, rectangular, tetrahedral, pentahedral, polyhedral, fibrous, lath, polygonal, elongated, acicular, needle, flat, flaky, cylindrical, sponge, cubic, cuboid, and combinations and variations thereof. If desired or necessary, the aggregate particles can be roughened to create cracks and fissures on the particle surface.

[0072] The aggregate material can include rock (e.g., fine powder), sand, glass, wood, paper, metal, plastic, polymer, mineral, manufacturing or processing waste (such as ash, carbon, or wood residuals), any of which can be crushed for use or used whole or a combination of the two.

[0073] The aggregate material can include organic or inorganic materials, for example, sand, rock, glass (e.g., Poraver), wood, paper, metal, plastic, polymer, mineral, recycled material, or combinations thereof. The aggregate particles can include beads, grains, rods, strands, fibers, flakes, crystals, crushed or ground material, or combinations thereof.

[0074] The aggregate particles can have a diameter (e.g., actual diameter, average diameter, or effective diameter) of about 50 mm or less, preferably about 25 mm or less, preferably about 20 mm or less, preferably about 10 mm or less, and preferably about 5 mm or less. In some embodiments, the aggregate material can be about 1 mm or less, about 0.5 mm or less, about 0.1 mm or less, and about 50 μιη or less. The particle size can include about 10 μιη to about 1 mm, about 100 μιη to about 0.5 mm, about 200 μιη to about 1 mm, about 1 μιη to about 200 μιη, about 10 nm to about 1 μιη, and about 10 nm to about 40 nm, and various combinations thereof. The aggregate particles can consist essentially of particles having a diameter less than 5 mm (e.g., less than or equal to about 4 mm, less than or equal to about 3 mm, less than or equal to about 2 mm, or less than or equal to about 1 mm).

[0075] The aggregate particles can be characterized by a fine size, and the size can be equal to or less than 250 microns, equal to or less than 200 microns, equal to or less than 150 microns, or equal to or less than 100 microns (reference examples include size of beach sand = 700 microns, size of fine sand = 250 microns; size of Portland cement = 74 microns; size of silt = 44 microns; size of smoke = 2 microns).

[0076] In some embodiments, large particles can be used, e.g., aggregate including centimeter or millimeter sized particles, e.g., gravel, stones, crushed rock, etc. In some embodiments, the size of the particles can range from 1 μιη or 10 μιη to 5 cm or more. In some embodiments, the particle starting material can consist of, or at least substantially consist of, small particles, especially micrometer sized particles. In other words, the size of the particles can be between or range from 1 μιη and 1 mm (1000 μιη), e.g., between or range from 100 μιη and 1000 μιη, or 100 μιη to 500 μιη, e.g., between or range from 200 μιη and 400 μιη, or 200 μιη and 300 μιη. However, the size of the large sized particles can be, e.g., between 1 mm and 2 mm, or have a wider size range, e.g., between 100 μιη and 2 mm.

[0077] The bridged calcium carbonate can adhere to individual aggregate particles to create bridges between the aggregate particles, or the bridged calcium carbonate can encapsulate individual aggregate particles. The bridged calcium carbonate can be formed from the reaction of calcium and carbonate ions. Enzymes or enzyme-producing organisms and reagents can be added together or separately to cause the formation of calcium carbonate. The calcium carbonate can be precipitated calcium carbonate. In some embodiments, the bridged calcium carbonate can be crystalline, such as bridged calcium carbonate crystals. In some embodiments, the bridged calcium carbonate crystals are ordered, pseudomorphous, or amorphous. In some embodiments, the bridged calcium carbonate crystals are ordered macroscopically and include a trigonal crystal structure, an orthorhombic crystal structure, or a hexagonal crystal structure.

[0078] The at least one organism or enzyme can include a urease-producing microorganism. The urease-producing microorganism can be selected from the group consisting of Sporosarcina pasteurii, Sporosarcina ureae, Proteus vulgaris, Bacillus sphaericus, Myxococcus xanthus, Proteus mirabilis, Bacillus megaterium, Helicobacter pylori, and combinations of two or more thereof.

[0079] The at least one organism or enzyme can include an enzyme-producing organism. The enzyme-producing organism can be an acid-producing microorganism. The acid-producing microorganism can be selected from the group consisting of Variovorax, Klebsiella, Pseudomonas, Bacillus, Exiguobacterium, Microbacterium, Curtobacterium, Rathayibacter, CellFimi2, Streptomyces, Raoultella, B. pumilus, B. safanensis, B. simplex, B. licheniformis, and combinations thereof.

[0080] In some embodiments, the construction material can additionally include a binding agent. The binding agent can adhere to or encapsulate the aggregate particles through a biological mechanism, such as an enzymatic process. In some embodiments, the binding agent can be an organism or an enzyme. The organism can be any urease-producing organism, acid-producing organism, or carbonic anhydrase-producing organism. The enzyme can be urease or carbonic anhydrase.

[0081] Physical properties of the construction material In some embodiments, the build material has a compressive strength of about 900 psi to about 3,500 psi. In some embodiments, the build material has a compressive strength of about 900 psi to about 1,000 psi, about 900 psi to about 1,100 psi, about 900 psi to about 1,200 psi, about 900 psi to about 1,300 psi, about 900 psi to about 1,400 psi, about 900 psi to about 1,600 psi, about 900 psi to about 1,800 psi, about 900 psi to about 2,000 psi, about 900 psi to about 2,500 psi, about 900 psi to about 3,000 psi, about 900 psi to about 3,500 psi, about 1,000 psi to about 1,100 psi, about 1,000 psi to about 1,200 psi, about 1,000 psi to about 1,300 psi, about 1,000 psi to about 1,400 psi, about 1,000 psi to about 1,600 psi, about 1,000 psi to about 1,800 psi, about 1,000 psi to about 2,000 psi, about 1,000 psi to about 2,500 psi, about 1,000 psi to about 3,000 psi, about 1,000 psi to about 3,500 psi, about 1,100 psi to about 1,200 psi, about 1,100 psi to about 1,300 psi, about 1,100 psi to about 1,400 psi, about 1,100 psi to about 1,600 psi, about 1,100 psi to about 1,800 psi, about 1,100 psi to about 2,000 psi, about 1,100 psi to about 2,500 psi, about 1,100 psi to about 3,000 psi, about 1,100 psi to about 3,500 psi, about 1,200 psi to about 1,300 psi, about 1,200 psi to about 1,400 psi, about 1,200 psi to about 1,600 psi, about 1,200 psi to about 1,800 psi, about 1,200 psi to about 2,000 psi, about 1,200 psi to about 2,500 psi, about 1,200 psi to about 3,000 psi, about 1,200 psi to about 3,500 psi, about 1,300 psi to about 1,400 psi, about 1,300 psi to about 1,600 psi, about 1,300 psi to about 1,800 psi, about 1,300 psi to about 2,000 psi, about 1,300 psi to about 2,500 psi, about 1,300 psi to about 3,about 1,400 psi to about 1,800 psi, about 1,400 psi to about 2,000 psi, about 1,400 psi to about 2,500 psi, about 1,400 psi to about 3,000 psi, about 1,400 psi to about 3,500 psi, about 1,600 psi to about 1,800 psi, about 1,600 psi to about 2,000 psi, about 1,600 psi to about 2,500 psi, about 1,600 psi to about 3,000 psi, about 1,600 psi to about 3,500 psi, about 1,800 psi to about 2,000 psi, about 1,800 psi to about 2,500 psi, about 1,800 psi to about 3,000 psi, about 1,800 psi to about 3,500 psi, about 2,000 psi to about 2,500 psi, about 2,000 psi to about 3,000 psi, about 2,000 psi to about 3,500 psi, about 2,500 psi to about 3,000 psi, about 2,500 psi to about 3,500 psi, or about 3,000 psi to about 3,500 psi. In some embodiments, the build material has a compressive strength of about 900 psi, about 1,000 psi, about 1,100 psi, about 1,200 psi, about 1,300 psi, about 1,400 psi, about 1,600 psi, about 1,800 psi, about 2,000 psi, about 2,500 psi, about 3,000 psi, or about 3,500 psi. In some embodiments, the build material has a compressive strength of at least about 900 psi, about 1,000 psi, about 1,100 psi, about 1,200 psi, about 1,300 psi, about 1,400 psi, about 1,600 psi, about 1,800 psi, about 2,000 psi, about 2,500 psi, or about 3,000 psi. In some embodiments, the build material has a compressive strength of at most about 1,000 psi, about 1,100 psi, about 1,200 psi, about 1,300 psi, about 1,400 psi, about 1,600 psi, about 1,800 psi, about 2,000 psi, about 2,500 psi, about 3,000 psi, or about 3,500 psi.

[0082] In some embodiments, the mass of calcium carbonate (bridging and non-bridging) in the build material is about 0.01 wt% to about 20 wt%. In some embodiments, the mass of calcium carbonate in the build material is about 0.01 wt% to about 0.1 wt%, about 0.01 wt% to about 0.5 wt%, about 0.01 wt% to about 1 wt%, about 0.01 wt% to about 2 wt%, about 0.01 wt% to about 3 wt%, about 0.01 wt% to about 4 wt%, about 0.01 wt% to about 5 wt%, about 0.01 wt% to about 7 wt%, about 0.01 wt% to about 10 wt%, about 0.01 wt% to about 15 wt%, about 0.01 wt% to about 20 wt%, about 0.1 wt% to about 0.5 wt%, about 0.1 wt% to about 1 wt%, about 0.1 wt% to about 2 wt%, about 0.1 wt% to about 3 wt%, about 0.1 wt% to about 4 wt%, about 0.1 wt% to about 5 wt%, about 0.1 wt% to about 7 wt%, about 0.1 wt% to about 10 wt%, about 0.1 wt% to about 15 wt%, about 0.1 wt% to about 20 wt%, about 0.5 wt% to about 1 wt%, about 0.5 wt% to about 2 wt%, about 0.5 wt% to about 3 wt%, about 0.5 wt% to about 4 wt%, about 0.5 wt% to about 5 wt%, about 0.5 wt% to about 7 wt%, about 0.5 wt% to about 10 wt%, about 0.5 wt% to about 15 wt%, about 0.5 wt% to about 20 wt%, about 1 wt% to about 2 wt%, about 1 wt% to about 3 wt%, about 1 wt% to about 4 wt%, about 1 wt% to about 5 wt%, about 1 wt% to about 7 wt%, about 1 wt% to about 10 wt%, about 1 wt% to about 15 wt%, about 1 wt% to about 20 wt%, about 2 wt% to about 3 wt%, about 2 wt% to about 4 wt%, about 2 wt% to about 5 wt%, about 2 wt% to about 7 wt%, about 2 wt% to about 10 wt%, about 2 wt% to about 15 wt%, about 2 wt% to about 20 wt%, about 3 wt% to about 4 wt%, about 3 wt% to about 5 wt%, about 3 wt% to about 7 wt%, about 3 wt% to about 10 wt%, about 3 wt% to about 15 wt%, about 3 wt% to about 20 wt%, about 4 wt% to about 5 wt%, about 4 wt% to about 7 wt%, about 4 wt% to about 10 wt%, about 4 wt% to about 15 wt%, about 4 wt% to about 20 wt%, about 5 wt% to about 7 wt%, about 5 wt% to about 10 wt%, about 5 wt% to about 15 wt%, about 5 wt% to about 20 wt%, about 7 wt% to about 10 wt%, about 7 wt% to about 15 wt%, about 7 wt% to about 20 wt%, about 10 wt% to about 15 wt%, about 10 wt% to about 20 wt%, or about 15 wt% to about 20 wt%.In some embodiments, the mass of calcium carbonate in the build material is about 0.01 wt%, about 0.1 wt%, about 0.5 wt%, about 1 wt%, about 2 wt%, about 3 wt%, about 4 wt%, about 5 wt%, about 7 wt%, about 10 wt%, about 15 wt%, or about 20 wt%. In some embodiments, the mass of calcium carbonate in the build material is at least about 0.01 wt%, about 0.1 wt%, about 0.5 wt%, about 1 wt%, about 2 wt%, about 3 wt%, about 4 wt%, about 5 wt%, about 7 wt%, about 10 wt%, or about 15 wt%. In some embodiments, the mass of calcium carbonate in the build material is at most about 0.1 wt%, about 0.5 wt%, about 1 wt%, about 2 wt%, about 3 wt%, about 4 wt%, about 5 wt%, about 7 wt%, about 10 wt%, about 15 wt%, or about 20 wt%.

[0083] System for producing a build material Described herein is a system for a plurality of frames, each of the plurality of frames comprising a bottom, one or more walls. In some embodiments, the bottom and the one or more walls collectively define a space. In some embodiments, the system can additionally comprise an inlet or feed source configured to add a cementing agent into the space. In some embodiments, the system can additionally comprise an outlet configured to remove a mobile phase from the space, wherein the mobile phase comprises a depleted cementing agent; (b) a heat exchange system in thermal communication with the plurality of frames; and (c) a controller in communication with the inlet, the outlet, and the heat exchange system, wherein the controller is configured to control a duty cycle of the system. The duty cycle comprises adding the cementing agent into the space, removing the mobile phase from the space, and maintaining a temperature of the bottom higher than a temperature of the cementing agent in the inlet when the cementing agent is added.

[0084] The heat exchange system can be programmed to introduce a temperature gradient along the plurality of frames. In some embodiments, the heat exchange system can be programmed to introduce and / or maintain a constant temperature along the plurality of frames. In some embodiments, the heat exchange system can be programmed to introduce discrete temperatures along different regions along the plurality of frames. As used herein, the heat exchange system can comprise a heat exchanger. The controller configured to control the duty cycle of the system can be a controller or an electronic system.

[0085] In some embodiments, the duty cycle enables the directed crystal growth of calcium carbonate to form bridged calcium carbonate. In some embodiments, the duty cycle further includes cooling / heating the bottom and / or one or more walls after the addition of the cementing agent is completed. In some embodiments, the duty cycle further includes cooling / heating the inlet during and / or after the addition of the cementing agent. In some embodiments, the duty cycle further includes adding air, oxygen, or ozone into the space or the top of the space; and / or removing air, oxygen, or ozone from the space or the top of the space. In some embodiments, the duty cycle further includes irradiating the space using ultraviolet light. In some embodiments, the duty cycle further includes vibrating the plurality of frames.

[0086] In some embodiments, the plurality of frames are also referred to as a plurality of reaction chambers. In some embodiments, each frame or reaction chamber is loaded with pre-treated or untreated aggregate particles. In some embodiments, a first feed solution / liquid is added to each frame / reaction chamber during a "feed" state / cycle of the duty cycle in a first tank. In some embodiments, the temperature of the feed solution / liquid is controlled. In some embodiments, no feed solution / liquid is provided to each frame / reaction chamber during a "bleed" state / cycle of the duty cycle. In some embodiments, the bottom of the frame / reaction chamber is heated by a heat exchange device or heater. In some embodiments, the feed solution / liquid is added from the top (or a top opening of the frame / reaction chamber or an inlet proximate to the top of the frame / reaction chamber). In some embodiments, the remaining feed solution / liquid is substantially drained before the start of the next cycle (e.g., a subsequent feed cycle / state) at or after the end of the bleed state / cycle.

[0087] Method of producing a construction material The manufacturing methods described herein can be used to manufacture any of the construction materials described herein. The method can include adding a plurality of aggregate particles and at least one organism or enzyme to a frame, thereby forming a plurality of aggregate particles within the frame. The aggregate particles can include at least one surface and a body enclosed by the at least one surface, wherein the at least one organism or enzyme resides in at least the body. A cementing agent can be fed into the plurality of aggregate particles within the frame. The method includes controlling a first temperature of the body, the first temperature being relative to (i) a second temperature of the feed cementing agent and / or (ii) a third temperature above the plurality of aggregate particles within the frame. The method includes forming bridged calcium carbonate crystals between at least two members of the plurality of aggregate particles within the frame, and forming non-bridged calcium carbonate crystals from a starting material produced by the at least one organism or enzyme.

[0088] In some embodiments, the process of producing the construction material can be a hydroculture process. In some embodiments, during the hydroculture process, each of the plurality of compressed aggregate units is fed with a calcium ion source chemical and a carbonate ion source chemical to form a biocement (or calcium carbonate formed from biologically produced calcium ions and / or carbonate ions), which is a biologically formed calcium carbonate. In some embodiments, this biocement (calcium carbonate) formation process can occur in the voids of the compressed aggregate units. In some embodiments, the calcium ions are biologically formed. In some embodiments, the carbonate ions are biologically formed. In some embodiments, both the calcium ions and the carbonate ions are biologically formed. As used herein, the term “biologically formed” generally refers to the formation of a product from a starting material by a biological agent. In some embodiments, the biological agent can be one or more enzymes, one or more microorganisms, or a combination thereof. In some embodiments, this biocement (calcium carbonate) formation process can bridge the gaps between the aggregate particles within each of the plurality of compressed aggregate units. In some embodiments, the hydroculture process includes some or all of the steps of aggregate blend preparation, nucleation, compression, drying, feeding, deodorization, and finishing. In some embodiments, each of the steps of aggregate blend preparation, nucleation, compression, drying, feeding, deodorization, and finishing is performed using controlled parameters. In some embodiments, the formed product can be evaluated according to parameters including, but not limited to, compressive strength, flexural strength, absorption, and sustained freeze-thaw cycles.

[0089] In some embodiments, the work cycle comprises a feed process that provides reagents to the framework. In some embodiments, the feed process comprises a work cycle that comprises a plurality of cycles with parameters comprising an individual feed time and a drain time for each cycle and a total number of cycles. In some embodiments, the work cycle of the feed process comprises a first slot and a plurality of subsequent slots. In some embodiments, the first slot has a first feed time of about 80 seconds to about 120 seconds. In some embodiments, the first feed time is about 80 seconds to about 85 seconds, about 85 seconds to about 90 seconds, about 90 seconds to about 95 seconds, about 95 seconds to about 100 seconds, about 100 seconds to about 105 seconds, about 105 seconds to about 110 seconds, about 110 seconds to about 115 seconds, or about 115 seconds to about 120 seconds. In some embodiments, the first feed time is about 80 seconds, 85 seconds, 90 seconds, 95 seconds, 100 seconds, 105 seconds, 110 seconds, 115 seconds, or 120 seconds. In some embodiments, the first feed time is about 100 seconds. In some embodiments, the first slot has a first drain time of about 800 seconds to about 1,000 seconds. In some embodiments, the first drain time is about 800 seconds to about 820 seconds, about 820 seconds to about 840 seconds, about 840 seconds to about 860 seconds, about 860 seconds to about 880 seconds, about 880 seconds to about 900 seconds, about 900 seconds to about 920 seconds, about 920 seconds to about 940 seconds, about 940 seconds to about 960 seconds, about 960 seconds to about 980 seconds, or about 980 seconds to about 1,000 seconds. In some embodiments, the first feed time is about 800 seconds, 810 seconds, 820 seconds, 830 seconds, 840 seconds, 850 seconds, 860 seconds, 870 seconds, 880 seconds, 890 seconds, 900 seconds, 910 seconds, 920 seconds, 930 seconds, 940 seconds, 950 seconds, 960 seconds, 970 seconds, 980 seconds, 990 seconds, or 1,000 seconds. In some embodiments, the first drain time is about 900 seconds.

[0090] In some embodiments, each of the plurality of subsequent tanks independently has a subsequent feed time of about 80 seconds to about 120 seconds. In some embodiments, the subsequent feed time is independently about 80 seconds to about 85 seconds, about 85 seconds to about 90 seconds, about 90 seconds to about 95 seconds, about 95 seconds to about 100 seconds, about 100 seconds to about 105 seconds, about 105 seconds to about 110 seconds, about 110 seconds to about 115 seconds, or about 115 seconds to about 120 seconds. In some embodiments, the subsequent feed time is independently about 80 seconds, 85 seconds, 90 seconds, 95 seconds, 100 seconds, 105 seconds, 110 seconds, 115 seconds, or 120 seconds. In some embodiments, the subsequent feed time is independently about 100 seconds. In some embodiments, each of the plurality of subsequent tanks independently has a subsequent discharge time of about 400 seconds to about 600 seconds. In some embodiments, the subsequent discharge time is independently about 400 seconds to about 420 seconds, about 420 seconds to about 440 seconds, about 440 seconds to about 460 seconds, about 460 seconds to about 480 seconds, about 480 seconds to about 500 seconds, about 500 seconds to about 520 seconds, about 520 seconds to about 540 seconds, about 540 seconds to about 560 seconds, about 560 seconds to about 580 seconds, or about 580 seconds to about 600 seconds. In some embodiments, the subsequent feed time is independently about 400 seconds, 410 seconds, 420 seconds, 430 seconds, 440 seconds, 450 seconds, 460 seconds, 470 seconds, 480 seconds, 490 seconds, 500 seconds, 510 seconds, 520 seconds, 530 seconds, 540 seconds, 550 seconds, 560 seconds, 570 seconds, 580 seconds, 590 seconds, or 600 seconds. In some embodiments, the subsequent discharge time is independently about 500 seconds. In some embodiments, the total number of cycles is about 15 to about 40 cycles. In some embodiments, the total number of cycles is about 15 to about 22, about 17 to about 24, about 19 to about 26, about 21 to about 28, about 23 to about 30, about 25 to about 32, about 27 to about 34, about 29 to about 36, about 31 to about 38, or about 33 to about 40 cycles. In some embodiments, the total number of cycles is about 23 to about 30 cycles. In some embodiments, the total number of cycles is about 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, or 40 cycles.

[0091] In some embodiments, the feed solution / liquid comprises urea and a calcium salt (e.g., calcium chloride or other Ca 2+(The salt). In some embodiments, the concentration of urea is from about 180 mM to about 330 mM. In some embodiments, the concentration of urea is from about 180 mM to about 190 mM, from about 190 mM to about 200 mM, from about 200 mM to about 210 mM, from about 210 mM to about 220 mM, from about 220 mM to about 230 mM, from about 230 mM to about 240 mM, from about 240 mM to about 250 mM, from about 250 mM to about 260 mM, from about 260 mM to about 270 mM, from about 270 mM to about 280 mM, from about 280 mM to about 290 mM, from about 290 mM to about 300 mM, from about 300 mM to about 310 mM, from about 310 mM to about 320 mM, or from about 320 mM to about 330 mM. In some embodiments, the concentration of urea is about 180 mM, 190 mM, 200 mM, 210 mM, 220 mM, 230 mM, 240 mM, 250 mM, 260 mM, 270 mM, 280 mM, 290 mM, 300 mM, 310 mM, 320 mM, or 330 mM. In some embodiments, the concentration of urea is about 230 mM. In some embodiments, the concentration of urea is about 240 mM. In some embodiments, the concentration of urea is about 240 mM. In some embodiments, the concentration of urea is about 260 mM. In some embodiments, the concentration of urea is about 270 mM. In some embodiments, the concentration of urea is about 280 mM. In some embodiments, the concentration of calcium chloride is from about 180 mM to about 330 mM. In some embodiments, the concentration of calcium chloride is about 180 mM to about 190 mM, about 190 mM to about 200 mM, about 200 mM to about 210 mM, about 210 mM to about 220 mM, about 220 mM to about 230 mM, about 230 mM to about 240 mM, about 240 mM to about 250 mM, about 250 mM to about 260 mM, about 260 mM to about 270 mM, about 270 mM to about 280 mM, about 280 mM to about 290 mM, about 290 mM to about 300 mM, about 300 mM to about 310 mM, about 310 mM to about 320 mM, or about 320 mM to about 330 mM. In some embodiments, the concentration of calcium chloride is about 180 mM, 190 mM, 200 mM, 210 mM, 220 mM, 230 mM, 240 mM, 250 mM, 260 mM, 270 mM, 280 mM, 290 mM, 300 mM, 310 mM, 320 mM, or 330 mM. In some embodiments, the concentration of calcium chloride is about 230 mM.In some embodiments, the concentration of calcium chloride is about 240 mM. In some embodiments, the concentration of calcium chloride is about 240 mM. In some embodiments, the concentration of calcium chloride is about 260 mM. In some embodiments, the concentration of calcium chloride is about 270 mM. In some embodiments, the concentration of calcium chloride is about 280 mM. In some embodiments, the concentration of urea is approximately equal to the concentration of calcium chloride. In some embodiments, the concentration of urea is different than the concentration of calcium chloride.

[0092] In some embodiments, the operation of controlling the first temperature of the body includes heating / cooling the bottom of the frame. In some embodiments, the operation of controlling the first temperature of the body includes heating the bottom of the frame. In some embodiments, the operation of controlling the first temperature of the body includes heating / cooling the feed cement. In some embodiments, the operation of controlling the first temperature of the body includes cooling the feed cement. In some embodiments, the operation of controlling the first temperature includes heating / cooling the solution phase above the plurality of aggregate particles within the frame.

[0093] In some embodiments, the duty cycle can include a controlled temperature range for the plurality of components. In some embodiments, the controlled temperature of the plurality of components includes a first temperature for each frame / body / reaction chamber (where the compacted aggregate is bound by the bio cement), a second temperature for the feed solution / liquid, and / or a difference between the first temperature and the second temperature. In some embodiments, the first temperature (i.e., the temperature for each frame / body / reaction chamber) is about 28°C to about 38°C. In some embodiments, the first temperature is about 28°C to about 30°C, about 30°C to about 32°C, about 32°C to about 34°C, about 34°C to about 36°C, or about 36°C to about 38°C. In some embodiments, the first temperature is about 32°C to about 34°C. In some embodiments, the first temperature is about 28°C, 29°C, 30°C, 31°C, 32°C, 33°C, 34°C, 35°C, 36°C, 37°C, or 38°C. In some embodiments, the second temperature (i.e., the temperature for the feed solution / liquid) is about 26°C to about 37°C. In some embodiments, the second temperature is about 26°C to about 27°C, about 27°C to about 28°C, about 28°C to about 29°C, about 29°C to about 30°C, about 30°C to about 31°C, about 31°C to about 32°C, about 32°C to about 33°C, about 33°C to about 34°C, about 34°C to about 35°C, about 35°C to about 36°C, or about 36°C to about 37°C. In some embodiments, the second temperature is about 30°C to about 31°C. In some embodiments, the second temperature is about 26°C, 27°C, 28°C, 29°C, 30°C, 31°C, 32°C, 33°C, 34°C, 35°C, 36°C, or 37°C. In some embodiments, the difference between the first temperature and the second temperature is about 1°C, about 2°C, or about 3°C. In some embodiments, the difference between the first temperature and the second temperature is about 1°C. In some embodiments, the difference between the first temperature and the second temperature is about 2°C. In some embodiments, the difference between the first temperature and the second temperature is about 3°C. In some embodiments, the first temperature is about 36°C and the second temperature is about 35°C. In some embodiments, the first temperature is about 36°C and the second temperature is about 34°C. In some embodiments, the first temperature is about 36°C and the second temperature is about 33°C. In some embodiments, the first temperature is about 35°C and the second temperature is about 34°C. In some embodiments, the first temperature is about 35°C and the second temperature is about 33°C. In some embodiments, the first temperature is about 35°C and the second temperature is about 32°C. In some embodiments, the first temperature is about 34°C and the second temperature is about 33°C. In some embodiments, the first temperature is about 34°C and the second temperature is about 32°C. In some embodiments, the first temperature is about 34°C and the second temperature is about 31°C. In some embodiments, the first temperature is about 33°C and the second temperature is about 32°C.In some embodiments, the first temperature is about 33 °C and the second temperature is about 31 °C. In some embodiments, the first temperature is about 33 °C and the second temperature is about 30 °C. In some embodiments, the first temperature is about 32 °C and the second temperature is about 31 °C. In some embodiments, the first temperature is about 32 °C and the second temperature is about 30 °C. In some embodiments, the first temperature is about 32 °C and the second temperature is about 29 °C. In some embodiments, the first temperature is about 31 °C and the second temperature is about 30 °C. In some embodiments, the first temperature is about 31 °C and the second temperature is about 29 °C. In some embodiments, the first temperature is about 31 °C and the second temperature is about 28 °C. In some embodiments, the first temperature is about 30 °C and the second temperature is about 29 °C. In some embodiments, the first temperature is about 30 °C and the second temperature is about 28 °C. In some embodiments, the first temperature is about 30 °C and the second temperature is about 27 °C. In some embodiments, the first temperature is about 29 °C and the second temperature is about 28 °C. In some embodiments, the first temperature is about 29 °C and the second temperature is about 27 °C. In some embodiments, the first temperature is about 29 °C and the second temperature is about 26 °C.

[0094] In some embodiments, the method can further include adding air, oxygen, or ozone to the top of the frame. In some embodiments, the method can further include removing air, oxygen, or ozone from the top of the frame.

[0095] In some embodiments, the method can further include curing the plurality of aggregate particles within the frame. In some embodiments, the operation of curing the plurality of aggregate particles within the frame includes irradiating the frame using ultraviolet light. In some embodiments, the method can further include vibrating the frame. In some embodiments, the method can further include removing the mobile phase from the frame, wherein the mobile phase includes depleted cementing agent. In some embodiments, the method can further include controlling a growth time of the at least one organism or enzyme in the body prior to feeding a dose of calcium ions to the plurality of aggregate particles within the frame. In some embodiments, the method can further include controlling a concentration of calcium and / or a rate of feeding of the dose of calcium to the plurality of aggregate particles within the frame.

[0096] In some embodiments, the aggregate particles can be roughened by mixing the particles together in a mixer or blender with enough force to create cracks and fissures on the surface of the particles; by adding to the aggregate particles a ball bearing or another substance with a hardness equal to or greater than the particles themselves; by passing the particles through a roughening agent such as sand, steel, or industrial diamond, or another roughening agent known to one of skill in the art, or combinations thereof.

[0097] The temperature, humidity, and / or pH of the plurality of aggregate particles within the framework during the reaction to form the construction material can be monitored and controlled. The operation to form bridging calcium carbonate crystals between at least two members of the plurality of aggregate particles within the framework can include at least one organism or enzyme, the at least one organism or enzyme further comprising urease or cells of urease-producing microorganisms. The operation to form bridging calcium carbonate crystals between at least two members of the plurality of aggregate particles within the framework can include acidogenic enzyme or cells of acidogenic microorganisms and / or carbonic anhydrase or cells of carbonic anhydrase-producing microorganisms.

[0098] The urease-producing microorganisms can include, but are not limited to, Paenibacillus barellis, Paenibacillus ureafaciens, Proteus vulgaris, Bacillus globigii, Myxococcus xanthus, Proteus mirabilis, Bacillus megaterium, Helicobacter pylori, and combinations of two or more thereof. In some embodiments, the cells comprise spores. The biocement can additionally comprise nutrients that promote the growth of the microorganisms or enzyme activity. In some embodiments, the nutrients include one or more of salts, amino acids, proteins, peptides, carbohydrates, sugars, polysaccharides, fatty acids, oils, vitamins, and minerals.

[0099] The cementing agent can include a calcium source. The cementing agent can include a urea source. The cementing agent includes calcium carbonate. The biocementing agent includes calcium chloride. The cementing agent can include cells of a microorganism that produces urease. In some embodiments, the microorganism that produces urea is selected from the group consisting of Pseudomonas spp., Delaya avenusta, Thiosphaera pantotropha, Pseudomonas stutzeri, Fragilaria crotonensis, Pseudoalteromonas spp., Pseudoalteromonas haloplanktis, Halomonas venusta, Pseudomonas balearica, Pseudomonas stutzeri, Bacillus megaterium, Exiguobacterium aurantiacum, Pseudoalteromonas aliena, Pseudoalteromonas luteoviolacea, E. coli, and variants, serotypes, mutants, recombinant forms, and combinations thereof. In some embodiments, the acid-producing microorganism is selected from the group consisting of Variovorax spp., Klebsiella spp., Pseudomonas spp., Bacillus spp., Exiguobacterium spp., Microbacterium spp., Parvibaculum spp., Raoultella spp., CellFimi2, Streptomyces spp., Raoultella spp., Parvibaculum decorscens, B. safensis, B. simplex, B. licheniformis, and combinations thereof.

[0100] In some embodiments, the acid produced by the acid-producing enzyme of the cells of the acid-producing microorganism is a carboxylic acid. In some embodiments, the acid produced by the acid-producing enzyme of the cells of the acid-producing microorganism is acetic acid, formic acid, propionic acid, butyric acid, gluconic acid, succinic acid, lactic acid, or citric acid. In some embodiments, the method further includes compacting the mixture to reduce the average linear distance between adjacent aggregate particles by at least about 25%. In some embodiments, the method further includes compacting the mixture to produce an absolute packing efficiency of at least about 50% of the aggregate particles.

[0101] In some embodiments, the method further comprises compacting the mixture by placing the mixture in a vibratory press and applying pressure and vibration to reduce the volume of void space between the plurality of aggregate particles. In some embodiments, the vibratory motor of the press is operated at a rotational speed of about 100 RPM to about 7200 RPM. In some embodiments, the vibratory motor of the press is operated at a duty cycle of 0.01% to about 100%. In some embodiments, the vibration and pressure are applied simultaneously. In some embodiments, the vibration and pressure are applied alternately. In some embodiments, the resulting construction material comprises at least about 2% calcium carbonate by weight. In some embodiments, the finished construction material comprises at most about 20% calcium carbonate by weight.

[0102] FIG. 1A An embodiment of a template 10 is depicted. In some cases, the template 10 can comprise a temporary structure, mold, or container for forming a plurality of aggregate particles. The template 10 contains aggregate material of a selected size, such as sand or other solid objects, while the aggregate is treated with a feed solution containing microorganisms (e.g., enzyme-producing bacteria) and / or enzymes (e.g., urease) and / or calcium ions and / or urea and / or other nutrients or ingredients. In one example, urease is formed by exposing an amount of urea to enzyme-producing bacteria, such as Bacillus pasteurii. The template 10 includes four vertical walls 12, an upper plate 14, and a lower plate 16, all of which are connected together to form a cavity 30 therebetween. The upper plate 14 has a plurality of inlets 18 thereon for feeding the cavity 30 with a feed solution (influent). The lower plate has a plurality of outlets 20 thereon for allowing effluent to exit the cavity 30.

[0103] In some embodiments, the feed solution can be delivered to the material within or into the cavity 30 by a feed source or a feed distribution system. The feed distribution system can utilize a spray or drip irrigation mechanism to distribute the feed solution.

[0104] The cavity 30 is adapted to receive loose masses of aggregate, such as sand. Some, if not all, of the plates are removable to facilitate removal of the contents (e.g., bricks) from the cavity 30. The vertical walls 12, or at least their interior surfaces, can be made of a non-reactive, non-porous material, such as cast or extruded acrylic. Additional sensors (e.g., temperature sensors, oxygen sensors, calcium ion sensors, carbon dioxide sensors, cameras, etc.) can be installed to monitor conditions inside or around the cavity 30. The addition or removal of the feed solution can be partially controlled according to data obtained by the sensors. The conditions and / or rate of introduction of the feed solution can be partially controlled according to data obtained by the sensors.

[0105] At the start of the process, aggregate material is layered or batched into the cavity. The aggregate material has been filtered through an aggregate filter to select the size of aggregate to be fed into the cavity 30. A top plate 14 is then placed on top of the aggregate material and the cavity 30 is sealed. A feed solution is introduced into the cavity through multiple inlets 18. The composition of the feed solution can be changed over time. The temperature of the feed solution before entering the cavity 30 can be controlled by a heat exchange module to heat or cool the feed solution to a desired temperature. The rate of feed solution introduction is controlled by a pump or other mechanism. Multiple outlets 20 are closed or partially closed when the feed solution is introduced into the cavity 30. When the multiple outlets 20 are open, effluent can be discharged from the cavity 30. An optional mechanical agitator can be installed inside the cavity 30, or a vibrator can be used to agitate the contents of the cavity 30. The feeding and discharging of the feed solution can be repeated multiple times. The time between the feeding and discharging of the feed solution can vary, including but not limited to one minute, ten minutes, tens of minutes, one hour, several hours, half a day, one day, one and a half days, two days, or other time periods. Additional inlets and / or outlets may be present around the main body of frame 10 (e.g., on vertical wall 12).

[0106] After the final run of the feed solution in the tank serving as aggregate material, all remaining solutions in cavity 30 are removed. Optionally, a washing solution is introduced into cavity 30 to rinse the formed product (e.g., bricks) and / or kill any remaining organisms. Optionally, air or inert air is introduced through an inlet, blown across cavity 30, and discharged through outlet 20. This air treatment can be added between feed solution / tank incubation periods to blow away or loosen coatings on the top surface. Such coatings on the top surface may clog the pores through which the feed solution enters the aggregate / brick body / interior. At the end of the tank treatment, the formed product is then removed from cavity 30 for testing / storage. For example, layers at different depths from the top surface of the brick can be prepared and analyzed by scanning electron microscopy (SEM) or other analytical methods. For example, bricks at different depths from the top surface of the brick can be cut. The properties of each layer (such as chemical composition, porosity, water absorption capacity, aggregate particle size distribution within the brick, mechanical strength, etc.) can be obtained, compared, and correlated with each other and with process conditions. In this way, the parameters of the tank treatment and / or the composition of the feed solution can be adjusted to improve the properties of the formed product (e.g., bricks).

[0107] like FIG. 1A As shown, the vertical wall 12 extends along a first direction (e.g., the Z direction), the upper plate 14 extends along a second direction orthogonal to the first direction, and the lower plate 16 extends along a second direction (e.g., the X direction).

[0108] FIG. 1B One embodiment depicts a cross-sectional view of structural material 68. Structural material 68 may include a plurality of aggregate particles. Structural material 68 has a top surface 62 and a bottom surface 64 opposite to the top surface 62. A vertical surface 66 may connect the top surface 62 and the bottom surface 64 or be orthogonal to them. In one embodiment, structural material 68 may use... FIG. 1A The template 10 shown is used to form or produce the material. The construction material 68 can be formed within the cavity 30 of the template 10. In this case, the top surface 62 can correspond to the first surface adjacent to the upper plate 14, and the bottom surface 64 can correspond to the adjacent... FIG. 1A The lower plate 16 shown is adjacent to a second surface. The top surface 62 may include a non-preferred surface that is closest to a plurality of inlets 18 for supplying feed solution to the construction material. FIG. 1A The depth of the vertical wall 12 can correspond to the depth or thickness of the structural material 68.

[0109] like FIG. 1B As shown, the vertical surface 66 extends along a first direction (e.g., the Z direction), the top surface 62 extends along a second direction orthogonal to the first direction, and the bottom surface 64 extends along a second direction (e.g., the X direction).

[0110] FIG. 1C Depicting FIG. 1B One embodiment of the cross-sectional view of the structural material 68 shown includes a horizontal slice 67 that cuts through the structural material 68 and extends along a second direction (e.g., the X direction). The horizontal slice 67 may have a certain material thickness (e.g., 0.1 mm to 10 cm, such as 0.1 mm to 1 mm, 1 mm to 2 mm, 1 mm to 5 mm, 1 mm to 1 cm, such as 1 cm to 2 cm, 1 cm to 5 cm, or 1 cm to 10 cm, such as about 0.1 mm, 0.5 mm, 1 mm, 1.5 mm, 2 mm, 5 mm, 1 cm, 2 cm, or 10 cm), and thus may include a planar segment extending along the second direction.

[0111] FIG. 1D Depicting FIG. 1B An embodiment of the construction material 68 shown in the side view. FIG. 1DAs shown, a first planar segment 54 of the structural material 68 adjacent to the top surface 62 has a first thickness 72, and a second planar segment 55 of the structural material 68 adjacent to the bottom surface 64 has a second thickness 76. The first thickness 72 may be substantially equal to the second thickness 76. In one example, the first thickness 72 may be 1.2 cm, and the second thickness 76 may be 1.1 cm. A third thickness 74 of the intermediate planar segment of the structural material 68 disposed between the first and second planar segments may be determined based on the height of the structural material 68 minus the first thickness 72 and the second thickness 74. The height of the structural material 68 may correspond to the height of the vertical surface 66. The vertical surface 66 of the structural material 68 may include a vertical wall connecting the top surface 62 and the bottom surface 64.

[0112] See FIG. 1B to FIG. 1D The top surface 62 of the structural material 68 shown may be parallel to the bottom surface 64. The top surface 62 may be substantially opposite to the bottom surface 64. A vertical surface 66 may include one of a plurality of vertical walls (or walls) between the top surface 62 and the bottom surface 64. The vertical surface 66 may structurally connect (or link) the top surface 62 and the bottom surface 64. The material body of the structural material 68 may cover or enclose the top surface 62, the vertical surface 66, and the bottom surface 64. The top surface 62, the vertical surface 66, and the bottom surface 64 may include the outer surfaces of the material body of the structural material 68.

[0113] like FIG. 1D As shown, the structural material 68 includes FIG. 1E to FIG. 1F A portion 52 of the enlarged structural material 68.

[0114] FIG. 1E Depicting before compression FIG. 1D An embodiment of aggregate particles within the structural material 68. FIG. 1F It depicts the state after the aggregate particles are compressed. FIG. 1D One embodiment of the aggregate particles within the structural material 68. The aggregate particles include aggregate particles 98, which may comprise particles of sand or gravel. FIG. 1E to FIG. 1F As shown, due to the compression of aggregate particles, the size of the pore space between aggregate particles decreases. Porosity can be defined as the volume of the pore space within a planar segment of the structural material 68 divided by the total volume of the planar segment. Due to the compression occurring within the structural material, the path restriction of fluid flow 92 is less than that of fluid flow 94.

[0115] like FIG. 1F As shown, organism 99 produces an environment in which calcium carbonate 97 is formed, which is structurally connected to some aggregate particles (including aggregate particles 98).

[0116] Due to the compression of structural materials, porosity decreases, as does the spacing between aggregate particles. For concrete, increased aggregate density is associated with increased compressive strength; however, increased aggregate density also reduces pore space. A technical problem with biocement products and structural materials containing biocement is that smaller pore sizes lead to reduced space for bacteria to be contained and for bacterial feed. Furthermore, the narrowing of pore throats due to reduced pore size can result in a reduced feed flow through the structural material. The combination of reduced space for bacteria to be contained, reduced space for bacterial feed, and reduced feed flow can lead to a decrease in bridging calcium carbonate within the structural material and a reduction in compressive strength.

[0117] FIG. 1G An embodiment depicts experimental results 82 showing the average compressive strength (in psi) of the structural material within a certain range of wetted green density (in g / cc) prior to the formation of bridging calcium carbonate and / or other binders. (See embodiment 82) FIG. 1G As shown, the average compressive strength of the finished structural material varies with the wetted green density before the application of the bio-cementing process. As illustrated, a wetted green density of 2.10 g / cc provides an average compressive strength of 180 psi, 1.80 g / cc provides 590 psi, and 1.95 g / cc provides a maximum average compressive strength of 850 psi. The maximum average compressive strength of the structural material is reached at a wetted green density of 1.95 g / cc. The wetted green density of the structural material can significantly affect the average compressive strength of the resulting structural material before the application of the bio-cementing process. The structural materials tested in this experiment were fed using various static feed schemes to eliminate confounding variables associated with flow-through feed.

[0118] FIG. 1H One embodiment is depicted in a plot showing the relationship between the percentage of total pore volume in a structural material and the pore diameter. As shown, most pores within the structural material have diameters between 170 mm and 300 mm, with pore diameters approaching 200 mm being the most common.

[0119] FIG. 1IOne embodiment of experimental results 83 showing the average change in electrical conductivity (or delta EC) of the construction material over a range of average dry green density of the construction material in g / cc is depicted. The average change in electrical conductivity is an indicator of the rate of progress of the biocementation process. The amount of cementitious agent consumed in the feed cycle varies with the green density of the construction material. As shown, the maximum average delta EC occurs at an average dry green density near 1.75 g / cc. The construction material tested in this experiment was fed in multiple static feed scenarios, eliminating confounding variables associated with flow-through feeding.

[0120] FIG. 1J One embodiment of a plot showing the total slice porosity at the location of a horizontal slice on a non-preferred surface of the construction material is depicted. See FIG. 6. FIG. 1C The horizontal slice 67 includes a horizontal slice through the construction material 68. As shown, the horizontal slice through the construction material 1.7 mm to 1.8 mm from the non-preferred surface of the construction material has a total slice porosity of about 6%.

[0121] FIG. 1K One embodiment of experimental results 80 showing the total open porosity of the construction material versus the number of slices is depicted. FIG. 1L One embodiment of a construction material body 69 including aggregate particles 98 bound together using calcium carbonate, including calcium carbonate 97, is depicted. As shown, a first horizontal slice 84 (slice #1) includes the topmost slice of the construction material body 69, a second horizontal slice 85 (slice #953) includes an interior slice through the construction material body 69, and a third horizontal slice 86 (slice #1961) includes the bottommost slice through the construction material body 69. The total open porosity of the second horizontal slice 85 (slice #953) is near 1%. The total open porosity of the first horizontal slice 84 (slice #1) and the third horizontal slice 86 (slice #1961) is greater than 2%.

[0122] FIG. 1M One embodiment of experimental results showing the compressive strength of the construction material versus the wet green density and the compressive strength versus the dry green density is depicted. The construction material tested in this experiment was fed in a manual flow-through feed system.

[0123] FIG. 1N One embodiment of experimental results showing the percentage of calcium carbonate formed (measured by TGA) of the construction material versus the wet green density and the percentage of calcium carbonate versus the dry green density is depicted. The construction material tested in this experiment was fed in a manual flow-through feed system.

[0124] FIG. 2A to FIG. 2BSEM images taken at the top surface layer of the final product (brick) are shown. Regions corresponding to granite and calcium carbonate are shown. FIG. 2A SEM images taken at the top surface layer of the final product (brick) are shown. Regions corresponding to granite and calcium carbonate are shown. FIG. 2B Regions within the boxes magnified and shown in FIG. 3A to FIG. 3B SEM images taken at the top middle layer of the final product (brick) are shown. Regions corresponding to granite and calcium carbonate are shown. FIG. 2A to FIG. 2B SEM images taken at the top surface layer of the final product (brick) are shown. Regions corresponding to granite and calcium carbonate are shown. FIG. 3A SEM images taken at the top surface layer of the final product (brick) are shown. Regions corresponding to granite and calcium carbonate are shown. FIG. 3B Regions within the boxes magnified and shown in FIG. 4A to FIG. 4B SEM images taken at the top surface layer of the final product (brick) are shown. Regions corresponding to granite and calcium carbonate are shown. FIG. 3A to FIG. 3B SEM images taken at the top surface layer of the final product (brick) are shown. Regions corresponding to granite and calcium carbonate are shown. FIG. 4A Regions within the boxes magnified and shown in FIG. 4B SEM / EDX analysis and comparison can be performed on different layers of bricks obtained from different batches (and thus, different feed solution batch conditions).

[0125] FIG. 5A One embodiment of a system for manufacturing construction materials using one or more biocementation processes is depicted. The system includes a chamber 578 for processing construction materials. As shown, the construction materials include bricks 592 and 593. While two bricks are depicted in the figure, other construction materials such as tiles and blocks can also be employed. The system also includes an overhead feed conditioner 588 for applying a cementing solution 573 to the construction materials within the processing chamber 578. The overhead feed conditioner 588 can adjust the temperature of the cementing solution applied to the construction materials within the processing chamber 578 and adjust the rate at which the cementing solution is applied to the construction materials. The overhead feed conditioner 588 can include heating and / or cooling elements for adjusting the temperature of the cementing solution applied to the construction materials. The system also includes a temperature and humidity controller 590 connected to a heat conductor 584 (e.g., a metal grid or metal strips) that is in thermal communication with the bricks 592-593 within the chamber 578. The heat conductor 584 can be directly connected or in physical contact with the bricks 592-593. A tray 586 provides structural support for the construction materials within the chamber 578. The heat conductor 584 is disposed between the tray 586 and the chamber 578.

[0126] In some embodiments, the temperature and humidity controller 590 can adjust the temperature of the construction materials within the chamber 578 through heating or cooling of the heat conductor 584. The temperature and humidity controller 590 can use temperature-regulated air flow to adjust or regulate the temperature of the construction materials within the chamber 578. The chamber 578 can completely enclose the construction materials or can provide an open or ventilated environment.

[0127] In some implementations, the temperature and humidity controller 590 may include a computing system. The computing system may include a network interface, processor, memory, and disk that communicate with each other. The network interface, processor, memory, and disk may include physical or virtualized components. In one instance, the network interface, processor, memory, and disk are provided by virtualized infrastructure or cloud-based infrastructure. The network interface may allow the computing system to connect to one or more networks. As an example, the network interface may include a wireless network interface and / or a wired network interface. The processor may allow the computing system to execute computer-readable instructions stored in memory to perform the processes described herein. The processor may include one or more processing units, such as one or more CPUs, one or more GPUs, and / or one or more NPUs. The memory may include one or more types of memory (e.g., RAM, SRAM, DRAM, EEPROM, flash memory). The disk may include a hard disk drive and / or a solid-state drive. In some cases, both memory and disk may include hardware storage devices.

[0128] like FIG. 5A As shown, the system for manufacturing building materials using one or more bio-binding processes also includes a feed tank 572 for collecting the remainder of the binder solution 573. The remainder or unused portion of the binder solution 573 that is used with the building materials or is not utilized by the building materials during the bio-binding process can be collected and reused during subsequent bio-binding processes. Filtered and / or recirculated binder solution 573 can be transferred to a top feed regulator 588 via pump 582. In some cases, particulate matter within the binder solution 573 collected by feed tank 572 can be allowed to settle within the collection tank, so that fluid drawn from the bottom of the collection tank can provide filtration for the recirculated binder solution 573. In one example, the inlet pipe for supplying recirculated binder solution 573 to pump 582 can be arranged at least 10 inches from the bottom of feed tank 572 (e.g., the distance 571 between the bottom of feed tank 572 and the inlet pipe can be 12 inches). The inlet pipe may include an additional filter for removing particles from the recirculated cementing solution 573.

[0129] In one embodiment, the temperature of the cementitious solution 573 applied to the top of the bricks 592-593 can be lower than the temperature applied to the bottom of the bricks 592-593 to reduce the rate of bio-cement formation in a portion of the bricks 592-593 closer to the top of the bricks 592-593 to which the cementitious solution 573 is applied. In one example, the temperature of the cementitious solution 573 applied to the top of the bricks 592-593 and the temperature applied to the bottom of the bricks 592-593 through the heat conductor 584 can be set such that the top 1 cm of the bricks 592-593 has a rate of bio-cement formation that is at least 20% to 50% slower than the rate of bio-cement formation of the bottom 1 cm of the bricks 592-593 closest to the heat conductor 584.

[0130] FIG. 5B A flowchart depicting one embodiment of a process for producing a construction material is depicted. In one embodiment, FIG. 5B The process of FIG. 1A is performed using the template shown. In some embodiments, FIG. 5B The process of FIG. 5A is performed using the system for manufacturing a construction material shown.

[0131] In step 502, a plurality of aggregate particles is obtained. The plurality of aggregate particles can be provided from a mixture of aggregate materials. The aggregate materials can include sand, gravel, and / or particulate materials. In step 504, the plurality of aggregate particles is formed or shaped. In one example, a press is used to compact the plurality of aggregate particles or shape the plurality of aggregate particles into a desired shape of a finished bio-cement product, thereby forming the plurality of aggregate particles.

[0132] In step 506, a cementitious solution comprising a cementing agent is provided. The cementing agent can be used to promote calcite precipitation to form a bond between aggregate particles within the plurality of aggregate particles. The cementitious solution can be stored within an overhead feed conditioner 588 in FIG. 5A In step 508, the cementitious solution is set to a first temperature. A heating plate or heat exchange system within the overhead feed conditioner 588 can be used to set and maintain the cementitious solution at the first temperature. In step 510, the plurality of aggregate particles is set to a second temperature. In one embodiment, the first temperature is lower than the second temperature. In another embodiment, the first temperature is higher than the second temperature. The plurality of aggregate particles can be set to the second temperature by direct physical contact with a heating element or heat conductor, such as the heat conductor 584 in FIG. 5A

[0133] In step 512, the cementitious solution is filtered. In some cases, a filter can be used to remove impurities from the cementitious solution in FIG. 5A ​The filter can include a particulate filter or a biological filter. In other cases, the feed tank 572 can provide filtration, as particulate matter within the collected cementing solution can be allowed to settle at the bottom of the feed tank 572, and an inlet tube used to recover the cementing solution from the feed tank 572 can be positioned to capture filtered liquid at a threshold distance from the bottom of the feed tank 572.

[0134] In step 514, a cementing solution is fed or applied to the plurality of aggregate particles. The cementing solution can be fed or applied to the plurality of aggregate particles when the cementing solution is at a first temperature and the plurality of aggregate particles is at a second temperature. In some cases, the temperature of the cementing solution is set such that the temperature of the liquid used to deliver the cementing agent is lower than the temperature of the plurality of aggregate particles or lower than the temperature of a bottom planar section of the plurality of aggregate particles. In some cases, the temperature of the cementing solution is set such that the temperature is at least a threshold amount lower than the temperature of the plurality of aggregate particles (e.g., the temperature of the cementing solution is at least 20 degrees lower than the temperature of the plurality of aggregate particles). In some cases, a bottom surface of the construction material including the plurality of aggregate particles is set to a second temperature that is higher than the first temperature of the cementing agent added to the plurality of aggregate particles.

[0135] In step 516, the plurality of aggregate particles is set to a third temperature. The plurality of aggregate particles can be set to a third temperature that is higher than the second temperature after the cementing solution is applied to the plurality of aggregate particles. In step 518, bridged calcium carbonate crystals are formed between at least two particles of the plurality of aggregate particles. The bridged calcium carbonate crystals can be formed when the temperature of the cementing solution is lower than the temperature of the plurality of aggregate particles. The bridged calcium carbonate crystals can be formed after the cementing solution is applied to the plurality of aggregate particles.

[0136] FIG. 5C A flowchart depicting one alternative embodiment of a process for producing a construction material is depicted. In one embodiment, FIG. 5C The process of FIG. 1 is performed using the system for manufacturing a construction material depicted in FIG. 2. In some embodiments, FIG. 1A The process of FIG. 1 is performed using the system for manufacturing a construction material depicted in FIG. 2. In some embodiments, FIG. 5C The process of FIG. 1 is performed using the system for manufacturing a construction material depicted in FIG. 2. In some embodiments, FIG. 5A The process of FIG. 1 is performed using the system for manufacturing a construction material depicted in FIG. 2. In some embodiments,

[0137] In step 532, a plurality of aggregate particles is provided. In step 534, the plurality of aggregate particles is compacted and / or formed. In step 536, a cementing solution including a cementing agent is provided. The cementing solution can be stored within a heated vessel having an overhead feed regulator, such as FIG. 5AThe column top feed regulator 588 is used. In step 538, the cementing solution is adjusted to a first temperature. The cementing solution can use... FIG. 5A The temperature and humidity are regulated by a temperature control circuit within a temperature and humidity controller 590, which is connected to a heat exchanger or heating plate within the top feed regulator. In step 540, the plurality of aggregate particles are adjusted to a second temperature. In one example, the plurality of aggregate particles can be... FIG. 5A Corresponding to brick 592 and thermally connected to heat conductor 584, the bottom portion of brick 592 can be set to or adjusted to a second temperature by the temperature of heat conductor 584. In step 542, the cementing solution is filtered. In step 544, the cementing solution is applied to the plurality of aggregate particles. In some cases, a drip or spray system can be used to apply the filtered cementing solution to the plurality of aggregate particles. In step 546, a bio-cementing process is performed. The bio-cementing process can cause a set of bridged calcium carbonate crystals to form between at least two particles of the plurality of aggregate particles.

[0138] FIG. 5D A flowchart illustrating an alternative implementation of the process for producing structural materials is provided. In one implementation, FIG. 5D The process of using FIG. 1A The template shown is used for implementation. In some implementations, FIG. 5D The process of using FIG. 5A The system shown is used to manufacture structural materials.

[0139] In step 552, a plurality of aggregate particles are provided or obtained. In step 554, the plurality of aggregate particles are formed and / or pressed. In step 556, a first filtration cementing solution is provided. The first filtration cementing solution contains a cementing agent. In step 558, the first filtration cementing solution is heated to a first temperature. In step 560, the first filtration cementing solution is applied to the plurality of aggregate particles. The first filtration cementing solution can be applied to the plurality of aggregate particles while the first filtration cementing solution is adjusted to the first temperature. In step 562, a first biocementing process is performed. The first biocementing process causes a first set of bridged calcium carbonate crystals to form between at least two particles of the plurality of aggregate particles. In step 564, at least a portion of the first filtration cementing solution is collected (e.g., in…). FIG. 5A (Inside the feed tank 572). In step 566, the first filtration cementing solution is filtered to produce a second filtration cementing solution. In step 568, the second filtration cementing solution is applied to the plurality of aggregate particles. In step 570, a second bio-cementing process is performed. The second bio-cementing process causes a second set of bridged calcium carbonate crystals to form within the structural material comprising the plurality of aggregate particles.

[0140] At least one embodiment of the disclosed technology includes a construction material comprising: (a) a plurality of aggregate particles; (b) bridging calcium carbonate crystals between at least two members of the plurality of aggregate particles; (c) non-bridging calcium carbonate crystals; and (d) at least one organism or enzyme that produces at least some of the bridging calcium carbonate crystals, wherein the construction material includes at least one surface and a body enclosed by the at least one surface, and wherein (i) a first average concentration of the non-bridging calcium carbonate crystals at or near the at least one surface is not greater than a second average concentration of the bridging calcium carbonate crystals at or near the at least one surface, or (ii) the second average concentration differs from a third average concentration of the bridging calcium carbonate crystals at or near a cross-section of the body by no more than 70%.

[0141] In some cases, the first average concentration is not greater than the second average concentration.

[0142] In some cases, the first average concentration is not greater than 99%, 95%, 90%, 85%, 80%, 75%, 70%, 65%, or 60% of the second average concentration.

[0143] In some cases, the second average concentration differs from the third average concentration by no more than 50%.

[0144] In some cases, the second average concentration differs from the third average concentration by no more than 69%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, or 10%.

[0145] In some cases, the second average concentration differs from the third average concentration by no more than 50%. The second average concentration differs from the third average concentration by no more than 49%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, or 10%.

[0146] In some cases, the first average concentration differs from a fourth average concentration of the non-bridging calcium carbonate crystals at or near a cross-section of the body by no more than 70%.

[0147] In some cases, the first average concentration differs from the fourth average concentration by no more than 69%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, or 10%.

[0148] In some cases, the at least one organism or enzyme includes a urease or a cell of a urease-producing microorganism.

[0149] In some cases, the at least one organism or enzyme includes an acid-producing enzyme or a cell of an acid-producing microorganism.

[0150] In some cases, the at least one organism or enzyme comprises a carbonic anhydrase or a cell of a microorganism that produces a carbonic anhydrase.

[0151] In some cases, the at least one organism or enzyme comprises a microorganism that produces urea.

[0152] In some cases, the average compressive strength of the construction material is at least about 1,500 pounds per square inch (psi).

[0153] In some cases, the average compressive strength is at least about 1,500 psi, 1,600 psi, 1,700 psi, 1,800 psi, 1,900 psi, 2,000 psi, 2,200 psi, 2,400 psi, 2,600 psi, 2,800 psi, 2,900 psi, 3,000 psi, 3,200 psi, 3,400 psi, 3,600 psi, 3,800 psi, 4,000 psi, 4,200 psi, 4,400 psi, 4,600 psi, 4,800 psi, 5,000 psi, 5,200 psi, 5,400 psi, 5,600 psi, 5,800 psi, 6,000 psi, 6,200 psi, 6,400 psi, 6,600 psi, or 6,800 psi.

[0154] In some cases, the at least one surface comprises a first surface and a second surface, and wherein the first average concentration at or near the first surface differs from the first average concentration at or near the second surface by no more than 50%.

[0155] In some cases, the first average concentration at or near the first surface differs from the first average concentration at or near the second surface by no more than 49%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, or 10%.

[0156] At least one embodiment of the disclosed technology includes a construction material comprising: (a) a first surface; (b) a second surface generally opposite the first surface; (c) one or more walls between and connecting the first surface and the second surface; and (d) a body enclosed by the first surface, the second surface, and the one or more walls; (e) a plurality of aggregate particles; (f) bridged calcium carbonate crystals between at least two members of the plurality of aggregate particles; (g) non-bridged calcium carbonate crystals; and (h) at least one organism or enzyme that produces at least some of the bridged calcium carbonate crystals, wherein a first average concentration of the non-bridged calcium carbonate crystals on the first surface is at least about 10% higher than a second average concentration of the non-bridged calcium carbonate crystals on the second surface.

[0157] In some cases, the first average concentration is at least about 15%, at least about 20%, at least about 25%, at least about 30%, at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at least about 65%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, or at least about 100% higher than the second average concentration.

[0158] In some cases, the first average concentration is at least about 10% higher than a third average concentration of non-bridging calcium carbonate crystals at or near the cross-section of the body.

[0159] In some cases, the first average concentration is at least about 15%, at least about 20%, at least about 25%, at least about 30%, at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at least about 65%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, or at least about 100% higher than the third average concentration.

[0160] In some cases, (i) the first average concentration is higher than a fourth average concentration of bridging calcium carbonate crystals at or near the first surface, and / or (ii) the fourth average concentration is not more than 70% different than a fifth average concentration of bridging calcium carbonate crystals at or near the cross-section of the body.

[0161] In some cases, the fourth average concentration is not more than 69%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, or 10% different than the fifth average concentration.

[0162] In some cases, the at least one organism or enzyme comprises a urease or a cell of a urease-producing microorganism.

[0163] In some cases, the at least one organism or enzyme comprises an acidogenic enzyme or a cell of an acidogenic microorganism.

[0164] In some cases, the at least one organism or enzyme comprises a carbonic anhydrase or a cell of a carbonic anhydrase-producing microorganism.

[0165] In some cases, the at least one organism or enzyme comprises a urea-producing microorganism.

[0166] In some cases, the average compressive strength of the build material is at least about 1,500 pounds per square inch (psi).

[0167] In some cases, the average compressive strength is at least about 1,500 psi, 1,600 psi, 1,700 psi, 1,800 psi, 1,900 psi, 2,000 psi, 2,200 psi, 2,400 psi, 2,600 psi, 2,800 psi, 2,900 psi, 3,000 psi, 3,200 psi, 3,400 psi, 3,600 psi, 3,800 psi, 4,000 psi, 4,200 psi, 4,400 psi, 4,600 psi, 4,800 psi, 5,000 psi, 5,200 psi, 5,400 psi, 5,600 psi, 5,800 psi, 6,000 psi, 6,200 psi, 6,400 psi, 6,600 psi, or 6,800 psi.

[0168] At least one embodiment of the disclosed technology includes a build material comprising: (a) a first surface; (b) a second surface generally opposite the first surface; (c) one or more walls between and connecting the first surface and the second surface; (d) a body enclosed by the first surface, the second surface, and the one or more walls, the body comprising a plurality of aggregate particles; (e) calcium carbonate; and (f) at least one organism or enzyme that produces at least some of the calcium carbonate formed between at least two members of the plurality of aggregate particles, wherein a first average weight percent of the calcium carbonate on the first surface differs from a second average weight percent of the calcium carbonate on the second surface by no more than 50%.

[0169] In some cases, the first average weight percent of the calcium carbonate on the cross-section of the body differs from a third average weight percent by no more than 50%.

[0170] In some cases, the first average weight percent differs from the second average weight percent by no more than 49%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, or 10%.

[0171] In some cases, the first average weight percent differs from the third average weight percent by no more than 49%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, or 10%.

[0172] At least one embodiment of the disclosed technology includes a construction material comprising: (a) a first surface; (b) a second surface generally opposite the first surface; (c) one or more walls between and connecting the first surface and the second surface; and (d) a body enclosed by the first surface, the second surface, and the one or more walls, the body comprising a plurality of aggregate particles; (e) calcium carbonate; and (f) at least one organism or enzyme that produces at least some of the calcium carbonate formed between at least two members of the plurality of aggregate particles, wherein a first average porosity of the construction material is from 15% to 50%.

[0173] In some cases, the first average porosity on the first surface is no more than 50% different than a second average porosity on the second surface.

[0174] In some cases, the first average porosity is no more than 49%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, or 10% different than the second average porosity.

[0175] In some cases, the first average porosity on the first surface is no more than 50% different than a third average porosity on a cross-section of the body.

[0176] In some cases, the first average porosity is no more than 49%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, or 10% different than the third average porosity.

[0177] In some cases, the first average porosity on the first surface is from 15% to 50%.

[0178] In some cases, the second average porosity on the second surface is from 15% to 50%.

[0179] In some cases, the third average porosity on a cross-section of the body is from 15% to 50%.

[0180] In some cases, the cross-section is at least 3 mm from the first surface and the second surface.

[0181] In some cases, the first average porosity on the first surface is greater than the third average porosity on a cross-section of the body.

[0182] In some cases, the second average porosity on the second surface is greater than the third average porosity.

[0183] At least one embodiment of the disclosed technology includes a construction material comprising: (a) a first surface; (b) a second surface substantially opposite to the first surface; (c) one or more walls between and connecting the first and second surfaces; (d) a body enclosed by the first surface, the second surface, and one or more walls, the body comprising a plurality of aggregate particles; (e) calcium carbonate; and (f) at least one organism or enzyme that generates at least some calcium carbonate formed between at least two members of the plurality of aggregate particles, wherein: 1) the average green density of the construction material is from about 1.5 g / cm³ to about 2.5 g / cc; or 2) the average finished density of the construction material is from about 1.8 g / cc to about 2.7 g / cc; or 3) the average void percentage of the green density is from about 25% to about 46%; or 4) the average percentage of voids filled in the finished product (or the average percentage of CaCO3 generated) is from about 5% to about 25%; or 5) any combination thereof.

[0184] In some cases, the average green density is about 1.5 g / cc to about 1.8 g / cc, about 1.6 g / cc to about 1.9 g / cc, about 1.7 g / cc to about 2.0 g / cc, about 1.8 g / cc to about 2.1 g / cc, about 1.9 g / cc to about 2.2 g / cc, about 2.0 g / cc to about 2.3 g / cc, or about 2.1 g / cc to about 2.4 g / cc.

[0185] In some cases, the average green density is about 1.7 g / cc to about 2.0 g / cc.

[0186] In some cases, the average green density is about 1.5 g / cc, 1.6 g / cc, 1.7 g / cc, 1.8 g / cc, 1.9 g / cc, 2.0 g / cc, 2.1 g / cc, 2.2 g / cc, 2.3 g / cc or 2.4 g / cc.

[0187] In some cases, the average finished product density is about 1.8 g / cc to about 1.9 g / cc, about 1.9 g / cc to about 2.0 g / cc, about 2.0 g / cc to about 2.1 g / cc, about 2.1 g / cc to about 2.2 g / cc, about 2.2 g / cc to about 2.3 g / cc, about 2.3 g / cc to about 2.4 g / cc, about 2.4 g / cc to about 2.5 g / cc, about 2.5 g / cc to about 2.6 g / cc, or about 2.6 g / cc to about 2.7 g / cc, wherein the finished product density is higher than the green body density.

[0188] In some cases, the average finished product density is about 2.0 g / cc to about 2.1 g / cc.

[0189] In some cases, the average finished product density is about 1.8 g / cc, 1.9 g / cc, 2.0 g / cc, 2.1 g / cc, 2.2 g / cc, 2.3 g / cc, 2.4 g / cc, 2.5 g / cc, 2.6 g / cc, or 2.7 g / cc.

[0190] In some cases, the average void percentage of the green density is about 25% to about 28%, about 28% to about 31%, about 31% to about 34%, about 34% to about 37%, about 37% to about 40%, about 40% to about 43%, or about 43% to about 46%.

[0191] In some cases, the average void percentage of the green density is about 30% to about 42%.

[0192] In some cases, the average void percentage of the green density is about 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%, 31%, 42%, 43%, 44%, 45%, 46%, or 47%.

[0193] In some cases, the average of the percentage of CaC03 produced is about 5% to about 10%, about 10% to about 15%, about 15% to about 20%, or about 20% to about 25%.

[0194] In some cases, the average of the percentage of CaC03 produced is 10% to about 23%.

[0195] In some cases, the average of the percentage of CaC03 produced is about 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, or 25%.

[0196] At least one embodiment of the disclosed technology includes a system for producing a construction material, the system comprising: (a) a plurality of frames, each of the plurality of frames comprising: (i) a bottom; (ii) one or more walls, wherein the bottom and the one or more walls collectively define a space; (iii) an inlet configured to add a cementitious agent into the space; and (iv) an outlet configured to remove a mobile phase from the space, wherein the mobile phase comprises a depleted cementitious agent; (b) a heat exchange system in thermal communication with the plurality of frames; and (c) a controller in communication with the inlet, the outlet, and the heat exchange system, wherein the controller is configured to control a duty cycle of the system, wherein the duty cycle comprises adding the cementitious agent into the space, removing the mobile phase from the space, and maintaining a temperature of the bottom above a temperature of the cementitious agent in the inlet while the cementitious agent is being added.

[0197] In some cases, the duty cycle further comprises cooling / heating the bottom and / or the one or more walls after the adding of the cementitious agent is completed.

[0198] In some cases, the duty cycle further comprises cooling / heating the inlet during and / or after the adding of the cementitious agent.

[0199] In some cases, the duty cycle further comprises adding air, oxygen, or ozone into the space or a top of the space; and / or removing air, oxygen, or ozone from the space or the top of the space.

[0200] In some cases, the duty cycle further comprises irradiating the space using ultraviolet light.

[0201] In some cases, the duty cycle further comprises vibrating the plurality of frames.

[0202] At least one embodiment of the disclosed technology includes a method of producing a construction material, the method comprising: (a) adding a plurality of aggregate particles and at least one organism or enzyme into a frame, thereby forming the plurality of aggregate particles within the frame comprising at least one surface and a body encapsulated by the at least one surface, wherein the at least one organism or enzyme resides in at least the body; (b) feeding a cementitious agent into the plurality of aggregate particles within the frame; (c) controlling a first temperature of the body, the first temperature being relative to (i) a second temperature of the fed cementitious agent, and / or (ii) a third temperature of a solution phase above the plurality of aggregate particles within the frame; and (d) forming bridging calcium carbonate crystals between at least two members of the plurality of aggregate particles within the frame, and forming non-bridging calcium carbonate crystals from a starting material produced by the at least one organism or enzyme.

[0203] In some cases, the controlling in (c) comprises heating / cooling a bottom of the frame.

[0204] In some cases, the control in (c) comprises heating the bottom of the frame.

[0205] In some cases, the control in (c) comprises heating / cooling the feed cement.

[0206] In some cases, the control in (c) comprises cooling the feed cement.

[0207] In some cases, the control in (c) comprises heating / cooling a solution phase above the plurality of aggregate particles within the frame.

[0208] In some cases, the control in (c) comprises cooling a solution phase above the plurality of aggregate particles within the frame.

[0209] In some cases, the method further comprises adding air, oxygen, or ozone into the top portion of the space; and / or removing air, oxygen, or ozone from the top portion of the frame.

[0210] In some cases, the method further comprises irradiating the frame using ultraviolet light.

[0211] In some cases, the method further comprises vibrating the plurality of frames.

[0212] In some cases, the method further comprises removing the mobile phase from the frame, wherein the mobile phase comprises depleted cement.

[0213] In some cases, the method further comprises controlling the growth time of at least one organism or enzyme in the body prior to feeding a dose of calcium ions to the plurality of aggregate particles within the frame.

[0214] In some cases, the method further comprises controlling the concentration of calcium and / or the rate of feeding of a dose of calcium to the plurality of aggregate particles within the frame.

[0215] At least one embodiment of the disclosed technology includes a construct material comprising: a plurality of aggregate particles bound together by one or more cohesive bridges, the cohesive bridges comprising calcium carbonate and at least a trace amount of a salt, the salt comprising an anion selected from the group consisting of: CI - , OCN - , and CN - ; wherein the trace amount is determined by detecting a relative anion intensity of at least 0.005 when measured using an imaging mass spectrometry technique such as time-of-flight secondary ion mass spectrometry (Tof-SIMS).

[0216] At least one embodiment of the disclosed technology includes a construction material comprising a plurality of aggregate particles bound together by one or more cohesive bridges, the cohesive bridges comprising calcium carbonate and at least one nitrogen-containing compound; wherein the ratio of nitrogen to calcium in the cohesive bridges is at least 0.15 (e.g., at least 0.2, 0.3, 0.4, 0.5, or 0.6) when measured by X-ray photoelectron spectroscopy at a surface of the construction material or at a cross-sectional surface of a portion of the construction material.

[0217] At least one embodiment of the disclosed technology includes a cementitious material comprising: (a) calcium; (b) a carbonate salt; and (c) at least 20 ppb of chloride, cyanide, cyanate, fulminate, and / or a combination of one or more thereof.

[0218] At least one embodiment of the disclosed technology includes a cementitious material comprising: (a) calcium; (b) a carbonate salt; and (c) 10 ppb to 1000 ppb of chloride, cyanide, cyanate, fulminate, and / or a combination of one or more thereof. In some cases, the cementitious material comprises 50 ppb to 150 ppb of chloride, 150 ppb to 500 ppb of chloride, or 500 ppb to 1000 ppb of chloride. In some cases, the cementitious material comprises 10 ppb to 20 ppb of cyanide, 10 ppb to 50 ppb of cyanide, or 50 ppb to 100 ppb of cyanide, 50 ppb to 150 ppb of cyanide, 100 ppb to 200 ppb of cyanide, 100 ppb to 500 ppb of cyanide, 200 ppb to 1000 ppb of cyanide, or 500 ppb to 1000 ppb of cyanide. In some cases, the cementitious material comprises 10 ppb to 20 ppb of cyanate, 10 ppb to 50 ppb of cyanate, or 50 ppb to 100 ppb of cyanate, 50 ppb to 150 ppb of cyanate, 100 ppb to 200 ppb of cyanate, 100 ppb to 500 ppb of cyanate, 200 ppb to 1000 ppb of cyanate, or 500 ppb to 1000 ppb of cyanate. In some cases, the cementitious material comprises 10 ppb to 20 ppb of fulminate, 10 ppb to 50 ppb of fulminate, or 50 ppb to 100 ppb of fulminate, 50 ppb to 150 ppb of fulminate, 100 ppb to 200 ppb of fulminate, 100 ppb to 500 ppb of fulminate, 200 ppb to 1000 ppb of fulminate, or 500 ppb to 1000 ppb of fulminate.

[0219] At least one embodiment of the disclosed technology includes a construction material comprising a plurality of aggregate particles bound together by one or more cohesive bridges, the cohesive bridges comprising calcite crystals having an average grain size of about 100 pm or less, a density of at least 10,000 crystals per square centimeter, as measured by TEM / SEM at a surface of the construction material.

[0220] At least one embodiment of the disclosed technology includes a construction material comprising a plurality of aggregate particles bound together by one or more cohesive bridges, the cohesive bridges comprising calcite crystals having an average grain size of about 100 pm or less, a density of 5K crystals per square centimeter to 500K crystals per square centimeter, as measured by TEM / SEM at a surface of the construction material.

[0221] At least one embodiment of the disclosed technology includes a construction material comprising a plurality of aggregate particles bound together by one or more cohesive bridges, the cohesive bridges comprising calcium; and a plurality of pores substantially free of solid material; wherein the construction material has about 20% to 50% by volume of pores, and the plurality of pores has an average pore diameter of about 1 pm to 400 pm (e.g., about 4 pm to 275 pm).

[0222] At least one embodiment of the disclosed technology includes a first surface; a second surface generally opposite the first surface; one or more walls between and connecting the first surface and the second surface; a plurality of aggregate particles enclosed by the first surface, the second surface, and the one or more walls; and calcium carbonate, wherein at least some of the calcium carbonate is formed between at least two of the plurality of aggregate particles as a result of biological activity of at least one organism or enzyme, and wherein a first average weight of a first portion of the calcium carbonate within a first planar section of the construction material differs by no more than 50% from a second average weight of a second portion of the calcium carbonate within a second planar section of the construction material.

[0223] The disclosure herein encompasses the subject matter shown in the following clauses: Clause 1. A construction material comprising: a first surface; a second surface generally opposite the first surface; one or more walls between and connecting the first surface and the second surface; a plurality of aggregate particles enclosed by the first surface, the second surface, and the one or more walls; and calcium carbonate, wherein at least some of the calcium carbonate is formed between at least two particles of the plurality of aggregate particles as a result of a biological activity of at least one organism or enzyme, and wherein a first average weight of a first portion of the calcium carbonate within a first planar section of the construction material differs from a second average weight of a second portion of the calcium carbonate within a second planar section of the construction material by no more than 50%.

[0224] Clause 2. The construction material of clause 1, wherein: a third portion of the calcium carbonate structurally indirectly connects the at least two particles of the plurality of aggregate particles.

[0225] Clause 3. The construction material of clause 1, wherein: the at least some of the calcium carbonate provides a structural connection between the at least two particles of the plurality of aggregate particles.

[0226] Clause 4. The construction material of clause 3, wherein: the at least some of the calcium carbonate comprises bridging calcium carbonate.

[0227] Clause 5. The construction material of clause 1, wherein: the first average weight of the first portion of the calcium carbonate is less than the second average weight of the second portion of the calcium carbonate.

[0228] Clause 6. The construction material of clause 1, wherein: the first planar section adjoins a non-preferred surface of the construction material; and the second planar section adjoins a preferred surface of the construction material.

[0229] Clause 7. The construction material of clause 1, wherein: the first average weight differs from a third average weight of a third planar section of the construction material disposed between the first planar section and the second planar section by no more than 20%.

[0230] Clause 8. The construction material of clause 7, wherein: the first average weight is greater than the third average weight.

[0231] Clause 17. The construction material of clause 1, wherein: the first planar section adjoins the first surface; and the second planar section adjoins the second surface.

[0232] Clause 18. A construction material comprising: a first surface; a second surface generally opposite the first surface; one or more walls between and connecting the first surface and the second surface; a body comprising a plurality of aggregate particles, the body enclosed by the first surface, the second surface, and the one or more walls; and calcium carbonate, wherein at least some of the calcium carbonate is formed between at least two particles of the plurality of aggregate particles by at least one organism or enzyme, and wherein the construction material has an average green density of about 1.52 grams per cubic centimeter (g / cc) to about 2.55 g / cc.

[0233] Clause 19. The construction material of clause 18, wherein: the construction material has an average void percentage of about 25% to about 46% within the construction material.

[0234] Clause 20. A construction material comprising: a first surface; a second surface generally opposite the first surface; one or more walls between and connecting the first surface and the second surface; a body comprising a plurality of aggregate particles, the body enclosed by the first surface, the second surface, and the one or more walls; and calcium carbonate, wherein at least some of the calcium carbonate is formed between at least two particles of the plurality of aggregate particles by at least one organism or enzyme, and wherein the construction material has an average finished density of about 1.83 grams per cubic centimeter (g / cc) to about 2.72 g / cc.

[0235] Clause 21. The construction material of clause 20, wherein: the construction material has an average void percentage of about 5% to about 25% within the construction material.

[0236] Clause 25. A method for producing a construction material, comprising: obtaining a plurality of aggregate particles; forming the plurality of aggregate particles; providing a cementitious solution comprising a cementitious agent; setting the cementitious solution to a first temperature; setting the plurality of aggregate particles to a second temperature different from the first temperature; feeding the cementitious solution to the plurality of aggregate particles when the cementitious solution is at the first temperature and the plurality of aggregate particles are at the second temperature; and forming a set of bridging calcium carbonate crystals between at least two particles of the plurality of aggregate particles after the cementitious solution is applied to the plurality of aggregate particles.

[0237] Clause 26. The method of clause 25, further comprising: filtering the cementitious solution prior to feeding the cementitious solution to the plurality of aggregate particles.

[0238] Clause 27. The method of clause 25, wherein: the first temperature is lower than the second temperature.

[0239] Clause 31. A method for producing a construction material, comprising: providing a plurality of aggregate particles; compacting the plurality of aggregate particles such that the construction material has an average dry green density of about 1.52 grams per cubic centimeter (g / cc) to about 2.55 g / cc; providing a cementing solution comprising a cementing agent; applying the cementing solution to the plurality of aggregate particles while the cementing solution is at a first temperature and the plurality of aggregate particles are at a second temperature different from the first temperature; and after the applying the cementing solution to the plurality of aggregate particles, conducting a biocementation process that causes a set of bridging calcium carbonate crystals to form between at least two particles of the plurality of aggregate particles.

[0240] Clause 32. The method of Clause 31, further comprising: outputting the construction material having an average finished density of the construction material of about 1.83 g / cc to about 2.72 g / cc.

[0241] Clause 33. The method of any one of Clauses 31 to 32, wherein: conducting the biocementation process comprises causing the set of bridging calcium carbonate crystals to form as a result of a biological activity of at least one organism or enzyme.

[0242] Clause 37. A method for producing a construction material, comprising: providing a plurality of aggregate particles; forming the plurality of aggregate particles; providing a first filtered cementing solution comprising a cementing agent; applying the first filtered cementing solution to the plurality of aggregate particles; conducting a first biocementation process that causes a first set of bridging calcium carbonate crystals to form between at least two particles of the plurality of aggregate particles; collecting at least a portion of the first filtered cementing solution while the first filtered cementing solution is being applied to the plurality of aggregate particles; filtering the first filtered cementing solution to produce a second filtered cementing solution; and applying the second filtered cementing solution to the plurality of aggregate particles.

[0243] Clause 39. The method of Clause 37, wherein: filtering the first filtered cementing solution to produce the second filtered cementing solution comprises allowing particulate matter within the first filtered cementing solution to settle in a collection tank.

[0244] The diagrams in the figures illustrated generally, by diagrammatic representations of the described technologies, methods and computer program products. As such, the drawings should not be considered limiting in scope, as the technologies, methods and computer program products described can be implemented in any number of ways, sizes, sizes and materials.

[0245] In some embodiments, the functions noted in the steps can be implemented using hardware, software, or combinations of hardware and software. For example, the hardware can include microcontrollers, microprocessors, field-programmable gate arrays (FPGAs), and electronic circuits.

[0246] For purposes of this document, it should be noted that the dimensions of the various features depicted in the drawings are not necessarily drawn to scale.

[0247] For purposes of this document, reference to “an implementation,” “one implementation,” “some implementations,” “another implementation,” and so forth, can be used interchangeably and mean one or more implementations including, but not limited to, one or more of the following: an implementation that is different from at least one other implementation, an implementation that is the same as one other implementation, an implementation that includes at least one feature of another implementation, an implementation that excludes at least one feature of another implementation, and / or an implementation where at least one feature of another implementation is varied.

[0248] For purposes of this document, a connection can be a direct connection or an indirect connection (e.g., through another part). In some cases, a connection between one element and another element can be connected, coupled, or attached through a third element. In some cases, a connection between one element and another element can be direct, without an intervening element.

[0249] For purposes of this document, the term “based on” can be understood as “based at least in part on.”

[0250] For purposes of this document, the use of the term “about” in conjunction with a numerical value or a range of values can mean that the value or range of values is within a margin of error that is acceptable in the art.

[0251] For purposes of this document, the term “set” of objects can mean one or more objects.

[0252] For the purposes of this document, the phrase “a first object corresponds to a second object” and “the first object corresponds to the second object” can refer to the first object and the second object being equivalent, similar, or related in property or function.

[0253] For the purposes of this document, the term “or” should be construed to have the meaning indicated in the Connective and Disjunctive Terms section. A list of items joined by the connective “or” should not be interpreted as requiring mutual exclusivity among that list’s items. Rather, such a list should be interpreted in the manner stated in the Connective and Disjunctive Terms section. As used herein, the terms “at least one,” “one or more,” and “and / or” are open-ended expressions that are intended to be interpreted in the manner indicated in the Connective and Disjunctive Terms section. The phrase “A and / or B” encompasses the embodiments of having A alone, having B alone, and having both A and B. The phrase “at least one of A, B, and C” encompasses the embodiments of having A alone, having B alone, having C alone, having both A and B, having both A and C, having both B and C, and having all of A, B, and C. As used herein, unless specifically indicated otherwise, the indefinite article “a” and “an” should generally be construed to mean “at least one” or “one or more.”

[0254] For the purposes of this document, whenever the term “at least,” “greater than,” or “greater than or equal to” precedes the first numerical value of a list of two or more numerical values, the term “at least,” “greater than,” or “greater than or equal to” applies to every numerical value of that list of numerical values. For example, greater than or equal to 1, 2, or 3 is equivalent to greater than or equal to 1, greater than or equal to 2, or greater than or equal to 3.

[0255] For the purposes of this document, whenever the term “no more than,” “less than,” or “less than or equal to” precedes the first numerical value of a list of two or more numerical values, the term “no more than,” “less than,” or “less than or equal to” applies to every numerical value of that list of numerical values. For example, less than or equal to 3, 2, or 1 is equivalent to less than or equal to 3, less than or equal to 2, or less than or equal to 1.

[0256] Some embodiments disclosed herein envision numerical ranges. When a range exists, it includes the range endpoints. Additionally, each subrange and value within the range exists as explicitly stated. The terms “about,” “approximately,” or “substantially” can mean within an acceptable margin of error for a particular value, which can depend in part on how the value is measured or determined, for example, limitations of the measurement system. For example, “about” can mean within one or more standard deviations according to practice in the art. Alternatively, “about” can mean a range of up to 20%, up to 10%, up to 5%, or up to 1% of a given value. When a particular value is described in the application and claims, unless otherwise specified, it may be assumed that the term “about” means within an acceptable margin of error for that particular value.

[0257] The various embodiments described above can be combined to provide further embodiments. These and other modifications can be made to the embodiments based on the detailed description above. Generally, the terminology used in the following claims should not be construed as limiting the claims to the specific embodiments disclosed in the specification and claims, but should be construed as including all possible embodiments and the full scope of equivalents enjoyed by such claims. Therefore, the claims are not limited by this disclosure.

Claims

1. A construction material comprising: a first surface (62); a second surface (64) generally opposite the first surface; one or more walls (66) between and connecting the first surface and the second surface; a plurality of aggregate particles (98) enclosed by the first surface, the second surface, and the one or more walls; and calcium carbonate (97), wherein at least some of the calcium carbonate is formed between at least two particles of the plurality of aggregate particles as a result of a biological activity of at least one organism or enzyme, and wherein a first average weight of a first portion of the calcium carbonate within a first planar section of the construction material differs from a second average weight of a second portion of the calcium carbonate within a second planar section of the construction material by no more than 50%.

2. The construction material of claim 1, wherein: a third portion of the calcium carbonate structurally indirectly connects the at least two particles of the plurality of aggregate particles.

3. The construction material of any one of claims 1-2, wherein: the at least some of the calcium carbonate provides a structural connection between the at least two particles of the plurality of aggregate particles.

4. The construction material of claim 3, wherein: the at least some of the calcium carbonate comprises bridging calcium carbonate.

5. The construction material of claim 1, wherein: the first average weight of the first portion of the calcium carbonate is less than the second average weight of the second portion of the calcium carbonate.

6. The construction material of any one of claims 1-5, wherein: the first planar section adjoins a non-preferred surface of the construction material; and the second planar section adjoins a preferred surface of the construction material.

7. The construction material of claim 1, wherein: the first average weight differs from a third average weight of a third planar section of the construction material disposed between the first planar section and the second planar section by no more than 20%.

8. The construction material of claim 7, wherein: the first average weight is greater than the third average weight.

9. The construction material of claim 7, wherein: the first average weight is less than the third average weight.

10. The construction material of claim 1, wherein: the first average weight differs from the second average weight by no more than 20%.

11. The construction material of claim 1, wherein: the calcium carbonate comprises bridging calcium carbonate crystals and non-bridging calcium carbonate crystals, a first average concentration of the non-bridging calcium carbonate crystals within the first planar section is less than a second average concentration of the bridging calcium carbonate crystals within the second planar section.

12. The construction material of claim 11, wherein: the second average concentration differs from a third average concentration of the bridging calcium carbonate crystals within a third planar section disposed between the first planar section and the second planar section by no more than 70%.

13. The construction material of claim 12, wherein: the third average concentration is greater than the first average concentration.

14. The build material of claim 11, wherein: the non-bridged calcium carbonate comprises precipitates that are not connected to any of the plurality of aggregate particles.

15. The build material of claim 11, wherein: the bridged calcium carbonate comprises precipitates that are connected to at least two of the plurality of aggregate particles.

16. The build material of claim 11, wherein: the at least one organism or enzyme comprises urease or cells of a urease-producing microorganism.

17. The build material of claim 1, wherein: the first planar section abuts the first surface; and the second planar section abuts the second surface.

18. A build material, comprising: a first surface (62); a second surface (64) generally opposite the first surface; one or more walls (66) between and connecting the first surface and the second surface; a body (69) comprising a plurality of aggregate particles, the body enclosed by the first surface, the second surface, and the one or more walls; and calcium carbonate (97), wherein at least some of the calcium carbonate is formed between at least two of the plurality of aggregate particles by at least one organism or enzyme, and wherein the build material has an average green density of about 1.52 grams per cubic centimeter (g / cc) to about 2.55 g / cc.

19. The build material of claim 18, wherein: an average void percentage within the build material is about 25% to about 46%.

20. A build material, comprising: a first surface (62); a second surface (64) generally opposite the first surface; one or more walls (66) between and connecting the first surface and the second surface; a body (69) comprising a plurality of aggregate particles, the body enclosed by the first surface, the second surface, and the one or more walls; and calcium carbonate (97), wherein at least some of the calcium carbonate is formed between at least two of the plurality of aggregate particles by at least one organism or enzyme, and wherein the build material has an average finished density of about 1.83 grams per cubic centimeter (g / cc) to about 2.72 g / cc.

21. The build material of claim 20, wherein: an average void percentage within the build material is about 5% to about 25%.

22. A build material, comprising: a first surface (62); a second surface (64) generally opposite the first surface; one or more walls (66) between and connecting the first surface and the second surface; a plurality of aggregate particles (98) enclosed by the first surface, the second surface, and the one or more walls; and calcium carbonate (97), wherein at least some of the calcium carbonate is formed between at least two of the plurality of aggregate particles as a result of biological activity of at least one organism or enzyme, and wherein the build material has an average green density of about 1.52 grams per cubic centimeter (g / cc) to about 2.55 g / cc. wherein a first average porosity within the first planar section of the build material is less than a second average porosity within a second planar section of the build material before the at least some of the calcium carbonate forms between the at least two members of the plurality of aggregate particles.

23. The build material of claim 22, wherein: a first average void percentage within the first planar section is less than a second average void percentage within the second planar section.

24. A build material, comprising: a first surface (62); a second surface (64) generally opposite the first surface; one or more walls (66) between and connecting the first surface and the second surface; a body (69) enclosed by the first surface, the second surface, and the one or more walls, the body comprising a plurality of aggregate particles (98); calcium carbonate (97); and at least one organism (99) or enzyme that produces at least some calcium carbonate formed between at least two members of the plurality of aggregate particles, wherein a first average weight percentage of calcium carbonate on the first surface is no more than 50% different than a second average weight percentage of calcium carbonate on the second surface.

25. A method for producing a build material, comprising: obtaining (502) a plurality of aggregate particles; forming (504) the plurality of aggregate particles; providing (506) a cement solution comprising a cementing agent; setting (508) the cement solution to a first temperature; setting (510) the plurality of aggregate particles to a second temperature different from the first temperature; feeding (514) the cement solution to the plurality of aggregate particles while the cement solution is at the first temperature and the plurality of aggregate particles are at the second temperature; and after applying the cement solution to the plurality of aggregate particles, causing (518) a set of bridging calcium carbonate crystals to form between at least two members of the plurality of aggregate particles.

26. The method of claim 25, further comprising: filtering the cement solution prior to feeding the cement solution to the plurality of aggregate particles.

27. The method of claim 25, wherein: the first temperature is less than the second temperature; and setting the plurality of aggregate particles to the second temperature comprises heating a form containing the plurality of aggregate particles to the second temperature.

28. The method of claim 25, further comprising: prior to causing the set of bridging calcium carbonate crystals to form between the at least two members of the plurality of aggregate particles, setting the plurality of aggregate particles to a third temperature different from the second temperature.

29. The method of claim 28, wherein: the third temperature is greater than the second temperature; and setting the plurality of aggregate particles to the third temperature comprises heating a heat conductor in physical contact with the plurality of aggregate particles to the third temperature.

30. The method of claim 25, further comprising: collecting a portion of the cement solution during feeding the cement solution to the plurality of aggregate particles; ​ and reusing the portion of the cementitious solution by reapplying the portion of the cementitious solution to the plurality of aggregate particles.

31. A method for producing a construction material, comprising: providing (532) a plurality of aggregate particles; pressing (534) the plurality of aggregate particles such that the construction material has an average dry green density of about 1.52 grams per cubic centimeter (g / cc) to about 2.55 g / cc; providing (536) a cementitious solution including a cementitious agent; applying (544) the cementitious solution to the plurality of aggregate particles when the cementitious solution is at a first temperature and the plurality of aggregate particles are at a second temperature different from the first temperature; and conducting (546), after the applying of the cementitious solution to the plurality of aggregate particles, a biocementation process that forms a set of bridging calcium carbonate crystals between at least two particles of the plurality of aggregate particles.

32. The method of claim 31, further comprising: outputting the construction material having an average finished density of the construction material of about 1.83 g / cc to about 2.72 g / cc.

33. The method of any one of claims 31-32, wherein: the average dry green density is about 1.73 g / cc to about 1.78 g / cc.

34. The method of any one of claims 31-32, wherein: the average dry green density is about 1.80 g / cc to about 2.00 g / cc.

35. The method of any one of claims 31-32, wherein: the average dry green density is about 2.15 g / cc to about 2.20 g / cc.

36. The method of any one of claims 31-35, wherein: conducting the biocementation process includes causing the set of bridging calcium carbonate crystals to form as a result of a biological activity of at least one organism or enzyme.

37. A method for producing a construction material, comprising: providing (552) a plurality of aggregate particles; forming (554) the plurality of aggregate particles; providing (556) a first filtered cementitious solution including a cementitious agent; applying (560) the first filtered cementitious solution to the plurality of aggregate particles; conducting (562) a first biocementation process that forms a first set of bridging calcium carbonate crystals between at least two particles of the plurality of aggregate particles; collecting (564) at least a portion of the first filtered cementitious solution while applying the first filtered cementitious solution to the plurality of aggregate particles; filtering (566) the first filtered cementitious solution to produce a second filtered cementitious solution; and applying (568) the second filtered cementitious solution to the plurality of aggregate particles.

38. The method of claim 37, further comprising: conducting (570) a second biocementation process that forms a second set of bridging calcium carbonate crystals within the construction material including the plurality of aggregate particles.

39. The method of any one of claims 37-38, wherein: Filtering the first filtered cementing solution to produce the second filtered cementing solution includes allowing particulate matter within the first filtered cementing solution to settle in a collection tank.

40. The method of claim 37, further comprising: setting the first filtered cementing solution to a first temperature; and setting the plurality of aggregate particles to a second temperature that is higher than the first temperature, the first biocementation process being performed while the first filtered cementing solution is at the first temperature and the plurality of aggregate particles is at the second temperature.

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