BIO-cement, methods of manufacture thereof and articles containing the same

Abstract

Disclosed herein is a bio-concrete composition comprising a bio-cement; where the bio-cement comprises a bio-mineralized algae, a silica source, pozzolan, biochar and / or bioash; and an aggregate; where the aggregate comprises a secondary binder, sand and / or rock. Disclosed herein too is a method of manufacturing a transportable dry composition comprising blending together a microorganism package; a nutrient; and a first liquid media; activating the microorganism package; subjecting the microorganism package to desiccation to form a bio-mineralized algae; mixing the bio-mineralized algae with a silica source, pozzolan, biochar and / or bioash to form a bio-cement; and mixing the bio-cement with an aggregate to form a bio-concrete.

Description

[0001] BIO-CEMENT, METHODS OF MANUFACTURE THEREOF AND ARTICLES CONTAINING THE SAME

[0002] BACKGROUND

[0003] This disclosure relates to a bio-cement, methods of manufacture thereof and articles containing the same.

[0004] Concrete is the most used construction material due to its resistance, durability and low cost in comparison to other construction materials. Annually, more than 10 billion tons of concrete are used at a global level and experts have predicted that the concrete demand is likely to grow to 16 billion tons in 2050. The current technology employed by the construction industry generates a negative impact on the global environment and economy. The industrial process involved in cement production from limestone (precursor of concrete), consumes between 2 and 3% of the global energy demand, generating 0.73—0.99 tons of COa / ton of cement produced, which accounts for about 8—10% of the global anthropogenic emissions of CO2 and 3.4% of the total CO2 global emissions.

[0005] Increase in consumption of concrete is a consequence of the susceptibility of infrastructure to physical, chemical and biological factors such as temperature variations, exposure to corrosive and radioactive substances, aggressive gases, natural disasters, and microbial activity. These factors cause microcracking, which affects mechanical and durability properties of concrete such as compressive strength, flexural strength and permeability, consequently reducing the useful life of concrete and increasing the cost of maintenance and repair of infrastructure. Although the global cost of concrete production ranges between 60 dollars / m3to 75 dollars / m3, the average cost for crack repair is about 130 dollars / m3, which reveals the high cost involved in the maintenance and repair of concrete structures.

[0006] It is therefore desirable to develop new forms of concrete that minimize the amount of carbon dioxide emitted into the atmosphere. It is also desirable to produce concrete that is less expensive than that currently produced.

[0007] SUMMARY

[0008] Disclosed herein is a bio-concrete composition comprising a bio-cement; where the biocement comprises a bio-mineralized algae, a silica source, pozzolan, biochar and / or bioash; and an aggregate; where the aggregate comprises a secondary binder, sand and / or rock.

[0009] Disclosed herein too is a method of manufacturing a transportable dry composition comprising blending together a microorganism package; a nutrient; and a first liquid media; activating the microorganism package; subjecting the microorganism package to desiccation to form a bio-mineralized algae; mixing the bio-mineralized algae with a silica source, pozzolan, biochar and / or bioash to form a bio-cement; and mixing the bio-cement with an aggregate to form a bio-concrete.

[0010] BRIEF DESCRIPTION OF THE FIGURES

[0011] FIG. 1 depicts one manner of manufacturing the bio-mineralized algae (bio-cement); and FIG. 2 depicts details of the bio-mineralization.

[0012] DETAILED DESCRIPTION

[0013] Disclosed herein is an environmentally friendly bio-cement that comprises biomineralized algae that can withdraw carbon dioxide from the atmosphere during the manufacturing of the bio-cement, during the utility of the bio-cement (in a construction project) or during both, the manufacturing of the bio-cement as well as during the utility of the biocement (in a construction project).

[0014] In an embodiment, the bio-cement comprises bio-mineralized algae, residual algae, a supplemental carbonate filler (e.g. oolitic aragonite), an alkali activator, a cementitious material, such as for example, a silica source (e.g., silica fume) and biochar / bio-ash. In an embodiment, the bio-cement may be used to manufacture a bio-concrete. The bio-cement is generally mixed with sand, rock and water to produce the bio-concrete. Table 1 provides an exemplary composition for a bio-cement, while Table 2 provides an exemplary composition for a bioconcrete. In Table 1, the weight percents are based on the total weight of the bio-cement, while in Table 2, the weight percent is based on the total weight of the bio-concrete. Preferred amounts for the various ingredients that constitute the bio-cement and bio-concrete are shown in the tables below. Table 1

[0015] Table 2

[0016] In an embodiment, the bio-cement may be packaged and shipped to a manufacturing site at which additional materials such as aggregate (e.g. sand and rock), fillers (e.g. calcium carbonate), cementitious or pozzolanic materials (such as slag, fly ash, natural pozzolans, etc.), and a liquid medium may be added to the bio-cement to form a bio-concrete. The bio-cement can therefore be converted into a bio-concrete, which may be used in a variety of building and construction applications. In an embodiment, an optional organic material such as polymers may be added to the bio-cement or to the bio-concrete if desired. In an embodiment, the bio-mineralized algae in an amount of up to 100 wt% may be transferred from a first site (at which it is manufactured) to a second site. The remainder of the ingredients (other than the bio-mineralized algae) in Table 1 (i.e., the primary binder, the alkali activator, the cementitious material and the biochar / bio-ash) and Table 2 (i.e., the secondary binder, the alkali activator, the cementitious or pozzolanic materials) may be added at the first site or at the second part, or may be added partially at the first site and partially at the second site to form the bio-concrete as detailed below. The first site is different from the second site. The first site is generally the manufacturing site while the second site is typically the site at which the bio-concrete is used.

[0017] This disclosure includes U.S. Provisional Application No. 63 / 466,040 filed on May 12, 2023, the entire contents of which are hereby incorporated by reference.

[0018] FIG. 1 depicts one manner of manufacturing the bio-mineralized algae (also called a biocement). Bio -mineralized algae refer to algae that have the ability to produce and deposit minerals (also called a “primary binder”) within their cellular structures. An example of such a primary binder is calcium carbonate (CaCO . In an embodiment, the primary binder is produced during the bio-mineralization. The calcium carbonate used as the primary binder may be in one of three crystalline forms when produced initially during bio-mineralization. These are vaterite, aragonite and calcite. Additionally, amorphous calcium carbonate may also be generated during the bio-mineralization process. It is desirable to have the calcite form the majority of the primary binder.

[0019] In an embodiment, the primary binder is a densifier and may have cementitious properties— it displays an ability to bind, harden, and gain strength upon setting. These properties are useful for materials used in construction and structural applications.

[0020] A secondary densifier (or binder) may also be added during the conversion of the biocement to a bio-concrete.

[0021] The algae are photosynthetic organisms that can be found in various aquatic environments. Some types of algae display an ability to extract minerals from their surroundings and use them to form hard structures within their cells. These structures often take the form of mineralized shells or skeletons.

[0022] The process of bio-mineralization in algae involves the precipitation of the primary binder, such as calcium carbonate or silica, in or around the algal cells. This mineralization provides structural support and protection to the algae. Additionally, these mineralized structures can accumulate over time, contributing to the formation of geological deposits, such as limestone or diatomaceous earth.

[0023] With reference to the FIG. 1, a method 100 for manufacturing the bio-mineralized algae comprises obtaining photosynthetic algae 102 and / or bacteria strains that are capable of using atmospheric carbon dioxide to produce minerals (that are preferably reaction products of the carbon dioxide) (see 102). In 104, the photosynthetic algae may be screened and isolated from other algal strains that could possibly interfere with the desired mineral production (see 104). A strain that efficiently produces the primary binder (e.g., calcium carbonate) is selected for biomineralization. A seed strain is established for cultivation and production cultures are inoculated 106 (see 106). Inoculating production cultures refers to the process of introducing a specific microorganism, such as an algae, a bacteria, yeast, or fungi, into a culture medium with the intention of promoting growth and reproduction of the specific micro-organism. The reasons for inoculating production cultures includes:

[0024] Scaling Up: Starting with a small, well-characterized culture and transferring it to a larger volume allows for the production of a larger quantity of the desired microorganism or its metabolites.

[0025] Maintaining Characteristics: Inoculation ensures that the culture maintains specific characteristics and properties, such as genetic traits or production capabilities.

[0026] Contamination Control: Inoculating a culture with a known microorganism helps prevent contamination by undesirable microbes. The inoculum is typically a pure culture, so it provides a controlled starting point.

[0027] Optimizing Conditions: In some cases, inoculation is used to introduce microorganisms into a culture medium with optimized conditions for growth, thereby enhancing productivity.

[0028] Following inoculation 106, bio-mineralization 108 is initiated. The processes including (102) through (106) may be conducted for a time period of 1 to 4 weeks. The time for replication is determined by the desired culture density which is ultimately a function of algae growth rate.

[0029] As noted above, bio-mineralization involves consuming carbon dioxide (or another gas from the atmosphere) resulting in the precipitation of minerals, such as calcium carbonate or silica, in or around the algal cells. The bio-mineralization may be conducted by feeding nutrients to the algae in a liquid media. The liquid media is typically an aqueous solution containing various elements, nutrients, and minerals (such as Mg, Na, K, N, and P). Bio-mineralization may also be conducted over a period of time of 2 hours to 7 days till the desired production cultures have reached the desired density. The selected time period will be based on yield, quality of product, and turnover time between batches.

[0030] Density determination is conducted by centrifuging a liter of sample, removing the liquid, and weighing the remaining material. Density determination during bio-mineralization is conducted in the same manner as it is during cultivation. During cultivation the highest density possible is targeted with minimal nutrient input (e.g., 5 g / L) within a range from 0. 1 to 20 grams per liter (g / L). During bio-mineralization, the highest density possible is targeted with an ideal percentage mass addition of —900% from the density measured during cultivation (the density increase can range from 100 to 1000%) such that the final product is approximately 0.1% to 10 weight percent (wt%) algae biomass and 90% to 99.9 wt% calcium carbonate.

[0031] The process of bio-mineralization 108 involves the controlled nucleation and growth of minerals under the influence of biological systems. Organisms can actively regulate the formation of these minerals, influencing their size, shape, and composition. The minerals produced through bio-mineralization often have unique properties compared to those formed through inorganic processes. In bio-mineralization 108, the algae that are cultured and inoculated are provided with a source of minerals such as calcium chloride to produce a first binder. It is to be noted that the processes 102 - 106 (which involves replication and growth of the microorganisms) may occur simultaneously and / or sequentially with the bio-mineralization 108.

[0032] Details of the bio-mineralization 108 are also depicted in the FIG. 2. On the left-hand side of the arrow in FIG. 2 is depicted the conditions for facilitating algal growth. The algal growth may be conducted in a reactor (which may include an indoor bioreactor, an outdoor pond, or both the indoor bioreactor and the outdoor pond). The indoor reactor or the outdoor pond is supplied with the liquid media. The liquid media used in the reactor is sometimes referred to herein as the first liquid media. It is to be noted that it is removed from the bio-cement. The liquid media and the nutrients are detailed later below.

[0033] Algae often have specific pH requirements for optimal growth. The pH of the water should be within a range that is suitable for the particular algal species being cultivated. A pH adjusting ingredient (e.g., sodium hydroxide) may be added during the bio-mineralization 108. The pH adjusting agent may be added in an amount effective to favor the formation of a carbonate-based primary binder as opposed to the formation of a bicarbonate-based binder (which is not desirable). The pH during bio-mineralization is typically maintained between 7 to 12, preferably 10 to 11.

[0034] During this bio-mineralization 108, the microorganisms extract carbon dioxide, nitrogen and / or sulfur from the atmosphere to produce the primary binder. Adequate levels of nutrients, including nitrogen, phosphorus, and micronutrients, are desirable for algal growth. The concentration of nutrients in the water should be carefully monitored and adjusted as needed. Water temperature is an important factor influencing algal metabolism. Different algae species have different temperature preferences, and maintaining an appropriate temperature is desirable for maximizing growth rates.

[0035] As depicted on the left-hand side of the arrow in FIG. 2, algal growth is facilitated by the use of nutrients. The nutrients are consumed by the microorganisms along with gases from the atmosphere (carbon dioxide, nitrogen, and the like) to produce the primary binder during the bio-mineralization process. The term “nutrient” as used herein refers to any chemical compound or composition which provides for algal growth or function. For example, for calcium- precipitating bacteria, a source of calcium is a nutrient. For polymer-forming bacteria, glucose can be a nutrient which the algae convert to a polymeric material. Co-factors which support bacteria viability (e.g., trace elements) are considered nutrients. The disclosed nutrient media comprises ingredients which provide for microorganism growth, as well as, the flowability of the bio-cement. Microorganism growth materials include inorganic salts and sources of carbon for microorganism metabolism. Some of the nutrients can also serve as the primary binder and some of the densifiers (that are formed during bio-mineralization) can function as nutrients.

[0036] Light either directly from the sun or from grow-lights may be used to facilitate algal growth. Algae use light for photosynthesis. In addition to water, sufficient light availability is a key consideration for algal cultivation.

[0037] With reference now again to the FIG. 1, following bio-mineralization, the biomineralized algae are separated from the water 110 and any other media that is used to facilitate bio-mineralization. The water may be recycled and reused to facilitate the bio-mineralization of additional algae that can be used in another production run for manufacturing the bio-cement. In an embodiment, the bio-mineralized algae may be separated from the water by typical separation processes such as filtration, centrifugation, flotation (e.g., sending air bubbles to bring the algae clumps to the surface), gravity sedimentation (e.g., using time and gravity to bring the algae clumps to the bottom), or a combination thereof. In an embodiment, gravity sedimentation is preferred.

[0038] In an embodiment, the separation of the liquid media from the bio-mineralized algae may be accomplished in conjunction with the drying of bio-mineralized algae to form the bio-cement or to form a precursor to the bio-cement. The bio-mineralized algae is dried (desiccated) 112 to form the bio-cement (see 112). In an embodiment, the bio-cement is formed due to alkaline activation of the bio-mineralized algae. Desiccation of algae refers to the process of drying out algae by removing water from their cells or tissues. Different algae species exhibit varying degrees of tolerance to desiccation. Some can survive drying out for extended periods, while others may be more sensitive. Adaptations may include the ability to produce protective compounds or to enter a dormant state during desiccation. Some algal species have evolved adaptations to tolerate desiccation as part of their life cycle. For example, certain types of green algae are known to form resistant structures called akinetes or spores that can withstand drying conditions. When the environment becomes favorable again, these structures may optionally rehydrate and resume growth.

[0039] The drying (desiccation 112) may be conducted by freeze drying, drum drying, spray drying, or other methods. The drying may be conducted (via spray drying) at an elevated temperature by spraying the ingredients into a region of elevated temperature. Spray drying is a method of forming a dry powder from a liquid or slurry by producing small droplets in a chamber at an elevated temperature. The elevated temperature is low enough and droplet residence time is short enough to not damage or destroy the microorganisms but high enough to facilitate evaporation of the moisture. The spray dryers may use some type of atomizer or spray nozzle to disperse the liquid or slurry into a controlled drop size spray.

[0040] The drying of the bio-mineralized algae may also involve freeze drying, where the liquid or slurry is converted to a dry powder through lyophilization. Freeze drying, also known as lyophilization or cryodesiccation, is a low temperature dehydration process that involves freezing the product and lowering pressure, removing the ice by sublimation.

[0041] The dried bio-mineralized algae is then subjected to optional pulverization to form a powdered bio-cement. The dried bio-mineralized microorganism may be pulverized to break down any aggregates, before or during the blending process. Pulverization can be conducted in a ball mill, Henschel mixture, waring blender, kneader, and the like, which apply shear and elongational forces to the dried bio-mineralized algae. Additionally, the ingredients of the dried composition may be dried to remove any moisture. The bio-cement therefore comprises the microorganisms surrounded by the first binder that has been pulverized or ground to a certain size. The bio-cement is also called a ready-mix. The pulverization facilitates homogeneous distribution during the formation of the bio-concrete.

[0042] The availability of the bio-cement as a dry powder is advantageous because it can be sold as a light-weight kit that can be transported to a site where it is to be used and activated at the site for use. At the site, one or more of additional micro-organisms, additional binder (e.g., an inorganic material), a substrate (e.g., sand) may be added to the dry powder along with the second liquid medium.

[0043] This permits the transport of a lighter material to the point of use, which saves costs and also results in lower fuel consumption. Since the bio-cement is used at room temperature without any external heating, it also results in energy savings and reduced contamination in the form of reduced emissions of carbonaceous gases. Carbonaceous gases are typically released into the atmosphere when energy (especially in the form of electricity) is produced. This process is therefore environmentally friendly in that it facilitates the removal of carbon dioxide from the atmosphere in order to produce the bio-cement.

[0044] In an embodiment, the bio-cement is available as a dry powder and comprises a desiccated microorganism package that can be shipped to a manufacturing site at which additional ingredients (collectively termed an aggregate) such as a substrate (also termed a scaffold), a second binder and a liquid medium may be added to produce a bio-concrete that can be used in a construction project (such as a building, a bridge, and the like). FIG. 2 depicts the bio-mineralization (formation of the bio-cement) on the right-hand side of the arrow. In the embodiment, depicted in the FIG. 2, the bio-mineralization results in the algae encrusting itself with a biomineral shell. An example of the bio-mineral shell is calcite (CaCO3).

[0045] The various ingredients used in bio-mineralization such as the microorganism package, nutrients and liquid media are listed below.

[0046] Microorganism package

[0047] The microorganism package preferably comprises a microorganism (e.g., an algae) that withdraws carbon dioxide from the atmosphere to produce the primary binder. In an embodiment, the primary binder comprises one or more of calcium carbonate, magnesium carbonate and / or calcium magnesium carbonate. In an embodiment, the calcium carbonate is preferably calcite, the magnesium carbonate is preferably magnesite, and the calcium magnesium carbonate is preferably dolomite. The microorganism may be a photosynthetic prokaryote or a eukaryote, in particular bacteria, yeast, or algae, or a combination thereof.

[0048] In an embodiment, the microorganism package may comprise two or more different types of microorganisms — a first microorganism and a secondary microorganism that can produce the primary binder. When two or more microorganisms are used to produce the primary binder, the primary binder may comprise an additional densifier in addition to calcium carbonate (e.g., calcite). The additional primary binder may be one or more of magnesium carbonate (e.g., magnesite) or calcium magnesium carbonate (e.g., dolomite). The first microorganism is preferably one that consumes carbon dioxide from the atmosphere to produce a carbonate salt that serves as the primary binder. The first and / or second microorganism may be photosynthetic prokaryotes or eukaryotes, in particular bacteria, yeast, or algae, or a combination thereof.

[0049] Examples of photosynthetic prokaryotic microorganisms include: Cyanobacteria

[0050] Green Sulfur Bacteria (Chlorobi)

[0051] Green Non-Sulfur Bacteria (Chloroflexi)

[0052] Heliobacteria

[0053] Acidobacteria (some are photosynthetic)

[0054] Proteobacteria

[0055] Purple Sulfur Bacteria (Chromatiaceae)

[0056] Purple Nonsulfur Bacteria

[0057] Green Bacteria (Chloroflexi and Chloracidobacterium) Chloroflexi bacterium

[0058] Purple Sulfur Bacteria (Ectothiorhodospiraceae) Purple Bacteria (Rhodospirillaceae)

[0059] Purple Nonsulfur Bacteria (Rhodospirillaceae)

[0060] Purple Sulfur Bacteria (Chromatiaceae)

[0061] Purple Bacteria (Rhodospirillaceae)

[0062] Purple Sulfur Bacteria (Ectothiorhodospiraceae)

[0063] Green Sulfur Bacteria (Chlorobi)

[0064] Green Nonsulfur Bacteria (Chloroflexi)

[0065] Heliobacteria

[0066] Acidobacteria (some are photosynthetic)

[0067] Proteobacteria

[0068] Purple Sulfur Bacteria (Chromatiaceae)

[0069] Purple Nonsulfur Bacteria

[0070] Green Bacteria (Chloroflexi and Chloracidobacterium)

[0071] Chloroflexi bacterium

[0072] Purple Sulfur Bacteria (Ectothiorhodospiraceae)

[0073] Purple Bacteria (Rhodospirillaceae)

[0074] Purple Nonsulfur Bacteria (Rhodospirillaceae)

[0075] Purple Sulfur Bacteria (Chromatiaceae)

[0076] Purple Bacteria (Rhodospirillaceae)

[0077] Purple Sulfur Bacteria (Ectothiorhodospiraceae)

[0078] Green Sulfur Bacteria (Chlorobi)

[0079] Green Nonsulfur Bacteria (Chloroflexi)

[0080] Heliobacteria

[0081] Acidobacteria (some are photosynthetic)

[0082] Proteobacteria

[0083] Purple Sulfur Bacteria (Chromatiaceae)

[0084] Purple Nonsulfur Bacteria

[0085] Green Bacteria (Chloroflexi and Chloracidobacterium)

[0086] Chloroflexi bacterium

[0087] Purple Sulfur Bacteria (Ectothiorhodospiraceae)

[0088] Purple Bacteria (Rhodospirillaceae)

[0089] Purple Nonsulfur Bacteria (Rhodospirillaceae)

[0090] Purple Sulfur Bacteria (Chromatiaceae)

[0091] Purple Bacteria (Rhodospirillaceae)

[0092] Purple Sulfur Bacteria (Ectothiorhodospiraceae)

[0093] Green Sulfur Bacteria (Chlorobi) Green Nonsulfur Bacteria (Chloroflexi)

[0094] Heliobacteria

[0095] Acidobacteria (some are photosynthetic)

[0096] Proteobacteria

[0097] Purple Sulfur Bacteria (Chromatiaceae)

[0098] Purple Nonsulfur Bacteria

[0099] Green Bacteria (Chloroflexi and Chloracidobacterium)

[0100] Chloroflexi bacterium

[0101] Purple Sulfur Bacteria (Ectothiorhodospiraceae)

[0102] Purple Bacteria (Rhodospirillaceae)

[0103] Purple Nonsulfur Bacteria (Rhodospirillaceae)

[0104] Purple Sulfur Bacteria (Chromatiaceae)

[0105] Purple Bacteria (Rhodospirillaceae)

[0106] Purple Sulfur Bacteria (Ectothiorhodospiraceae)

[0107] Green Sulfur Bacteria (Chlorobi)

[0108] Green Nonsulfur Bacteria (Chloroflexi)

[0109] Heliobacteria

[0110] Acidobacteria (some are photosynthetic)

[0111] Proteobacteria

[0112] Purple Sulfur Bacteria (Chromatiaceae)

[0113] Purple Nonsulfur Bacteria

[0114] Green Bacteria (Chloroflexi and Chloracidobacterium)

[0115] Chloroflexi bacterium

[0116] Purple Sulfur Bacteria (Ectothiorhodospiraceae)

[0117] Purple Bacteria (Rhodospirillaceae)

[0118] Purple Nonsulfur Bacteria (Rhodospirillaceae)

[0119] Purple Sulfur Bacteria (Chromatiaceae)

[0120] Purple Bacteria (Rhodospirillaceae)

[0121] Purple Sulfur Bacteria (Ectothiorhodospiraceae)

[0122] Green Sulfur Bacteria (Chlorobi)

[0123] Green Nonsulfur Bacteria (Chloroflexi)

[0124] Heliobacteria

[0125] Acidobacteria (some are photosynthetic)

[0126] Proteobacteria

[0127] Purple Sulfur Bacteria (Chromatiaceae)

[0128] Purple Nonsulfur Bacteria Green Bacteria (Chloroflexi and Chloracidobacterium)

[0129] Chloroflexi bacterium

[0130] Purple Sulfur Bacteria (Ectothiorhodospiraceae)

[0131] Purple Bacteria (Rhodospirillaceae)

[0132] Purple Nonsulfur Bacteria (Rhodospirillaceae)

[0133] Purple Sulfur Bacteria (Chromatiaceae)

[0134] Purple Bacteria (Rhodospirillaceae)

[0135] Purple Sulfur Bacteria (Ectothiorhodospiraceae)

[0136] Green Sulfur Bacteria (Chlorobi)

[0137] Green Nonsulfur Bacteria (Chloroflexi)

[0138] Heliobacteria

[0139] Acidobacteria (some are photosynthetic)

[0140] Proteobacteria

[0141] Purple Sulfur Bacteria (Chromatiaceae)

[0142] Purple Nonsulfur Bacteria

[0143] Green Bacteria (Chloroflexi and Chloracidobacterium)

[0144] Chloroflexi bacterium

[0145] Anabaena cylindrica

[0146] Nostoc commune

[0147] Spirulina platensis

[0148] Synechococcus elongatus

[0149] Prochlorococcus marinus

[0150] Microcystis aeruginosa

[0151] Oscillatoria tenuis

[0152] Gloeocapsa magma

[0153] Trichodesmium erythraeum

[0154] Cyanothece sp.

[0155] Chlorobium limicola

[0156] Chlorobaculum tepidum

[0157] Chlorobium phaeobacteroides

[0158] Chloroflexus aurantiacus

[0159] Roseiflexus castenholzii

[0160] Heliobacterium modesticaldum

[0161] Heliobacterium chlorum

[0162] Acidobacterium capsulatum

[0163] Rhodopseudomonas palustris Rhodobacter sphaeroides Rhodocyclus tenuis Chromatium okenii Thiocapsa roseopersicina Rhodo spirillum centenum Chloracidobacterium thermophilum Chloroflexus aggregans Oscillochloris trichoides Herpetosiphon aurantiacus Thiocystis violascens Allochromatium vino sum Marichromatium purpuratum Nitrosococcus oceani Nitro sopumilus maritimus Ectothiorhodo spira shapo shnikovii Ectothiorhodospira halochloris Ectothiorhodo spira mobilis Lamprocystis purpurea Rubrivivax gelatinosus Rhodopseudomonas viridis Rhodopseudomonas acidophila Rhodopseudomonas palustris CGA009 Rhodobacter capsulatus B IO Rhodobacter sphaeroides 2.4.1 Rhodopseudomonas palustris BisB5 Roseiflexus castenholzii Chlorobaculum parvum Roseiflexus sp.

[0164] Chloroflexi bacterium MS-G Chloroflexi bacterium GNS-1 Chloroflexus sp.

[0165] Thiodictyon sp. KC-1 Thiodictyon sp. CLB 1001 Rhodobacter capsulatus SB 1003 Rhodobacter sphaeroides ATCC 17029 Rhodobacter sphaeroides ATCC 17096 Rhodobacter sphaeroides ATCC 17925 Heliophilum prolipovicii Chlorobaculum parvum Chlorobaculum tepidum Oscillatoria limosa Nostoc punctiforme Synechocystis sp.

[0166] Chloracidobacterium aurantiacum

[0167] Synechocystis aquatilis Thiocapsa rosea Thiodictyon sp. KC-1 Thiodictyon sp. CLB 1001 Marichromatium purpuratum Nitrosococcus oceani Nitro sopumilus maritimus Ectothiorhodo spira shapo shnikovii Ectothiorhodospira halochloris Ectothiorhodo spira mobilis Lamprocystis purpurea Rubrivivax gelatinosus Rhodopseudomonas viridis Rhodopseudomonas acidophila Rhodopseudomonas palustris CGA009 Rhodobacter capsulatus B IO Roseiflexus sp.

[0168] Chlorobaculum parvum Chloroflexus sp.

[0169] Oscillatoria limosa Nostoc punctiforme Chlorobium limicola

[0170] Chlorobium phaeobacteroides Chloroflexus aurantiacus Gloeocapsa magma Trichodesmium erythraeum Cyanothece sp.

[0171] Microcoleus chthonoplastes Phormidium sp.

[0172] Chloroflexi bacterium MS-G

[0173] Chloroflexi bacterium GNS-1

[0174] Aphanocapsa sp.

[0175] Geitlerinema sp.

[0176] Anabaenopsis sp.

[0177] Leptolyngbya sp.

[0178] Moorea producens

[0179] Chroococcidiopsis sp., or a combination thereof.

[0180] Preferred examples of photosynthetic prokaryotic microorganisms include:

[0181] Anabaena cylindrica

[0182] Nostoc commune

[0183] Spirulina platensis

[0184] Synechococcus elongatus

[0185] Prochlorococcus marinus

[0186] Microcystis aeruginosa

[0187] Oscillatoria tenuis

[0188] Gloeocapsa magma

[0189] Trichodesmium erythraeum

[0190] Cyanothece sp.

[0191] Chlorobium limicola

[0192] Chlorobaculum tepidum

[0193] Chlorobium phaeobacteroides

[0194] Chloroflexus aurantiacus

[0195] Roseiflexus castenholzii

[0196] Heliobacterium modesticaldum

[0197] Heliobacterium chlorum

[0198] Acidobacterium capsulatum

[0199] Rhodopseudomonas palustris

[0200] Rhodobacter sphaeroides

[0201] Rhodocyclus tenuis

[0202] Chromatium okenii

[0203] Thiocapsa roseopersicina

[0204] Rhodo spirillum centenum

[0205] Chloracidobacterium thermophilum

[0206] Chloroflexus aggregans Oscillochloris trichoides

[0207] Herpetosiphon aurantiacus

[0208] Thiocystis violascens

[0209] Allochromatium vino sum

[0210] Marichromatium purpuratum

[0211] Nitrosococcus oceani

[0212] Nitro sopumilus maritimus

[0213] Ectothiorhodo spira shapo shnikovii

[0214] Ectothiorhodospira halochloris

[0215] Ectothiorhodo spira mobilis

[0216] Lamprocystis purpurea

[0217] Rubrivivax gelatinosus

[0218] Rhodopseudomonas viridis

[0219] Rhodopseudomonas acidophila

[0220] Rhodopseudomonas palustris CGA009

[0221] Rhodobacter capsulatus B IO

[0222] Rhodobacter sphaeroides 2.4.1

[0223] Rhodopseudomonas palustris BisB5

[0224] Roseiflexus castenholzii

[0225] Chlorobaculum parvum

[0226] Roseiflexus sp.

[0227] Chloroflexi bacterium MS-G

[0228] Chloroflexi bacterium GNS-1

[0229] Chloroflexus sp.

[0230] Thiodictyon sp. KC-1

[0231] Thiodictyon sp. CLB 1001

[0232] Rhodobacter capsulatus SB 1003

[0233] Rhodobacter sphaeroides ATCC 17029

[0234] Rhodobacter sphaeroides ATCC 17096

[0235] Rhodobacter sphaeroides ATCC 17925

[0236] Heliophilum prolipovicii

[0237] Chlorobaculum parvum

[0238] Chlorobaculum tepidum

[0239] Oscillatoria limosa

[0240] Nostoc punctiforme

[0241] Synechocystis sp. Chloracidobacterium aurantiacum

[0242] Synechocystis aquatilis

[0243] Thiocapsa rosea

[0244] Thiodictyon sp. KC-1

[0245] Thiodictyon sp. CLB 1001

[0246] Marichromatium purpuratum

[0247] Nitrosococcus oceani

[0248] Nitro sopumilus maritimus

[0249] Ectothiorhodo spira shapo shnikovii

[0250] Ectothiorhodospira halochloris

[0251] Ectothiorhodo spira mobilis

[0252] Lamprocystis purpurea

[0253] Rubrivivax gelatinosus

[0254] Rhodopseudomonas viridis

[0255] Rhodopseudomonas acidophila

[0256] Rhodopseudomonas palustris CGA009

[0257] Rhodobacter capsulatus B IO

[0258] Roseiflexus sp.

[0259] Chlorobaculum parvum

[0260] Chloroflexus sp.

[0261] Oscillatoria limosa

[0262] Nostoc punctiforme

[0263] Chlorobium limicola

[0264] Chlorobium phaeobacteroides

[0265] Chloroflexus aurantiacus

[0266] Gloeocapsa magma

[0267] Trichodesmium erythraeum

[0268] Cyanothece sp.

[0269] Microcoleus chthonoplastes

[0270] Phormidium sp.

[0271] Chloroflexi bacterium MS-G

[0272] Chloroflexi bacterium GNS-1

[0273] Aphanocapsa sp.

[0274] Geitlerinema sp.

[0275] Anabaenopsis sp.

[0276] Leptolyngbya sp. Moorea producens

[0277] Chroococcidiopsis sp., or a combination thereof.

[0278] Examples of photosynthetic eukaryotic microorganisms include:

[0279] Chlamydomonas reinhardtii

[0280] Euglena gracilis

[0281] Spirogyra

[0282] Diatoms (e.g., Thalassiosira)

[0283] Chlorella

[0284] Volvox

[0285] Desmids

[0286] Cyanophora paradoxa (a cryptomonad)

[0287] Dinoflagellates (e.g., Karenia brevis)

[0288] Cryptophytes (e.g., Rhodomonas)

[0289] Brown algae (Phaeophyta)

[0290] Red algae (Rhodophyta)

[0291] Green algae (e.g., Ulva, Spirogyra)

[0292] Micrasterias

[0293] Clos terium

[0294] Oedogonium

[0295] Coccolithophores (e.g., Emiliania huxleyi)

[0296] Synura

[0297] Prymnesium parvum

[0298] Aphanizomenon

[0299] Chlamydomonas reinhardtii

[0300] Euglena gracilis

[0301] Spirogyra sp.

[0302] Thalassiosira pseudonana

[0303] Chlorella vulgaris

[0304] Volvox carteri

[0305] Micrasterias denticulata

[0306] Clos terium sp.

[0307] Oedogonium sp.

[0308] Emiliania huxleyi

[0309] Prymnesium parvum

[0310] Chara vulgaris

[0311] Cladophora glomerata Ectocarpus siliculosus Phacus sp.

[0312] Vaucheria sp.

[0313] Dictyostelium discoideum

[0314] Ochromonas danica

[0315] Nannochloropsis sp.

[0316] Gymnodinium sp.

[0317] Peridinium sp.

[0318] Phaeocystis pouchetii

[0319] Ostreococcus tauri

[0320] Gonyaulax spinifera

[0321] Dinobryon divergens

[0322] Actinophrys sol

[0323] Symbiodinium microadriaticum

[0324] Laminaria digitata

[0325] Euglena longa

[0326] Pandorina morum

[0327] Zygnema sp.

[0328] Mesotaenium sp.

[0329] Dinophysis acuminata

[0330] Noctiluca scintillans

[0331] Porphyra purpurea

[0332] Porphyridium cruentum Griffithsia sp.

[0333] Corallina officinalis

[0334] Theileria parva

[0335] Chromera velia

[0336] Dasya sp.

[0337] Chaetoceros sp.

[0338] Coscinodiscus sp.

[0339] Trichodesmium erythraeum Chrysochromulina sp. Bathycoccus prasinos Scenedesmus obliquus

[0340] Selenastrum capricornutum Pediastrum boryanum Synura petersenii Botryococcus braunii Bulbochaete sp. Sarcodina sp. Chattonella marina Tetraselmis chuii Eutreptiella gymnastica Myrmecia ingens Haematococcus pluvialis Monoraphidium minutum Ankistrodesmus falcatus Sphaerocystis schroeteri Chlorogonium elongatum Nannochloris atomus Fragilariopsis cylindrus Chaetoceros muelleri Scytonema sp.

[0341] Aphanochaete repens Clostridium perfringens Microcoleus vaginatus Navicula gregaria Rhizosolenia calcar-avis Paraphysomonas imperforata Neochloris oleoabundans Isochrysis galbana Cyanidium caldarium Tribonema sp.

[0342] Dinobryon sertularia Botrydium granulatum Penium margaritaceum Desmodesmus quadricauda Staurastrum brachiatum Pteridium sp. Klebsormidium flaccidum Phaeodactylum tricomutum Nannochloris maculata Navicula radiosa

[0343] Prochlorococcus marinus

[0344] Aegagropila linnaei

[0345] Rhizoclonium hieroglyphicum

[0346] Acetabularia acetabulum

[0347] Chrysochromulina parva

[0348] Ochrosphaera neapolitana

[0349] Tetrastrum Cambridge!

[0350] Cephaleuros parasiticus

[0351] Micromonas pusilia

[0352] Pyramimonas tetrarhynchus

[0353] Heterocapsa pygmaea

[0354] Amphidinium carterae

[0355] Amphora coffeaeformis

[0356] Scherffelia dubia, or a combination thereof.

[0357] Preferred examples of photosynthetic eukaryotic microorganisms include:

[0358] Chlamydomonas reinhardtii

[0359] Euglena gracilis

[0360] Spirogyra sp.

[0361] Thalassiosira pseudonana

[0362] Chlorella vulgaris

[0363] Volvox carter!

[0364] Micrasterias denticulata

[0365] Clos terium sp.

[0366] Oedogonium sp.

[0367] Emiliania huxleyi

[0368] Prymnesium parvum

[0369] Chara vulgaris

[0370] Cladophora glomerata

[0371] Ectocarpus siliculosus

[0372] Phacus sp.

[0373] Vaucheria sp.

[0374] Dictyostelium discoideum

[0375] Ochromonas danica

[0376] Nannochloropsis sp.

[0377] Gymnodinium sp. Peridinium sp.

[0378] Phaeocystis pouchetii Ostreococcus tauri Gonyaulax spinifera Dinobryon divergens Actinophrys sol Symbiodinium microadriaticum Laminaria digitata Euglena longa Pandorina morum

[0379] Zygnema sp. Mesotaenium sp. Dinophysis acuminata Noctiluca scintillans Porphyra purpurea Porphyridium cruentum Griffithsia sp.

[0380] Corallina officinalis Theileria parva Chromera velia Dasya sp.

[0381] Chaetoceros sp. Coscinodiscus sp. Trichodesmium erythraeum Chrysochromulina sp. Bathycoccus prasinos Scenedesmus obliquus Selenastrum capricornutum Pediastrum boryanum Synura petersenii Botryococcus braunii Bulbochaete sp.

[0382] Sarcodina sp.

[0383] Chattonella marina Tetraselmis chuii Eutreptiella gymnastica

[0384] 11 Myrmecia ingens

[0385] Haematococcus pluvialis

[0386] Monoraphidium minutum

[0387] Ankistrodesmus falcatus

[0388] Sphaerocystis schroeteri

[0389] Chlorogonium elongatum

[0390] Nannochloris atomus

[0391] Fragilariopsis cylindrus

[0392] Chaetoceros muelleri

[0393] Scytonema sp.

[0394] Aphanochaete repens

[0395] Clostridium perfringens

[0396] Microcoleus vaginatus

[0397] Navicula gregaria

[0398] Rhizosolenia calcar-avis

[0399] Paraphysomonas imperforata

[0400] Neochloris oleoabundans

[0401] Isochrysis galbana

[0402] Cyanidium caldarium

[0403] Tribonema sp.

[0404] Dinobryon sertularia

[0405] Botrydium granulatum

[0406] Penium margaritaceum

[0407] Desmodesmus quadricauda

[0408] Staurastrum brachiatum

[0409] Pteridium sp.

[0410] Klebsormidium flaccidum

[0411] Phaeodactylum tricomutum

[0412] Nannochloris maculata

[0413] Navicula radiosa

[0414] Prochlorococcus marinus

[0415] Aegagropila linnaei

[0416] Rhizoclonium hieroglyphicum

[0417] Acetabularia acetabulum

[0418] Chrysochromulina parva

[0419] Ochrosphaera neapolitana Tetrastrum Cambridge!

[0420] Cephaleuros parasiticus

[0421] Micromonas pusilia

[0422] Pyramimonas tetrarhynchus

[0423] Heterocapsa pygmaea Amphidinium c rterae Amphora coffeaeformis Scherffelia dubia, or a combination thereof.

[0424] Nutrients

[0425] The nutrients are consumed by the microorganism(s) along with gases from the atmosphere (carbon dioxide, nitrogen, and the like) to produce the primary binder during the biomineralization process. The term “nutrient” as used herein refers to any chemical compound or composition which provides for microorganism growth or function. For example, for calcium- precipitating bacteria, calcium may be used as a nutrient. Co-factors which support bacteria viability (e.g., trace elements) are considered nutrients. The disclosed nutrient media comprise ingredients which provide for microorganism growth, as well as the flowability of the biocement. Microorganism growth materials include inorganic salts and sources of carbon for microorganism metabolism. Some of the nutrients can serve as the binder and some of the binder can function as nutrients. In an embodiment, residual nutrients present in the bio-cement can act as functionalizing agents in the final bio-cement, i.e., they can promote interactions between the binder and other ingredients present in the bio-cement.

[0426] The nutrients that are added to facilitate bio-mineralization include macronutrients and / or micronutrients. Macronutrients refer to elements that are used by organisms in relatively large quantities for their growth and development. Micronutrients, also known as trace elements or trace metals, are elements used by living organisms in smaller quantities compared to macronutrients. While micronutrients are needed in smaller amounts, they play useful roles in various biological processes, including bio-mineralization.

[0427] Macronutrients may include primary nutrients and secondary nutrients. Primary nutrients include nitrogen-containing compounds, phosphorus-containing compounds, potassium containing compounds, or a combination thereof. Nitrogen containing compounds include urea, ammonium nitrate, ammonium sulfate, calcium ammonium nitrate, sodium nitrate, or a combination thereof. Phosphorus-containing compounds include triple superphosphate, diammonium phosphate, mono-ammonium phosphate, rock phosphate, sodium phosphate, potassium phosphate, or a combination thereof. Triple superphosphate (TSP) is a highly concentrated phosphorus fertilizer. It is produced by reacting rock phosphate with phosphoric acid. The process involves treating phosphate rock with an excess of phosphoric acid, resulting in a fertilizer with a high concentration of soluble phosphorus. Rock phosphate is a natural mineral deposit that is mined for its phosphorus content. The main component of rock phosphate is the mineral apatite, which contains various forms of calcium phosphate.

[0428] Potassium containing compounds include potassium chloride, potassium sulfate, potassium nitrate, potassium phosphate, dipotassium phosphate, or a combination thereof.

[0429] Secondary nutrients include calcium-containing compounds, magnesium-containing compounds, sulfur in elemental form or sulfur-containing compounds, or a combination thereof. Calcium-containing compounds include calcium carbonate, calcium sulfate, calcium nitrate, or a combination thereof. Magnesium-containing compounds include magnesium sulfate (Epsom salt), magnesium oxide, or a combination thereof. Sulfur-containing compounds include ammonium sulfate.

[0430] Micronutrients include ferrous sulfate, iron chelates, ferric sulfate ( 'cSCE*?! hO), manganese sulfate, manganese chelates, zinc sulfate, zinc chelates, copper sulfate, copper chelates, borax, boric acid, boron chelates, sodium molybdate, potassium chloride, cobalt nitrate, cobalt chloride, sodium nitrate, calcium chloride hydrate (CaCE^HsO), boric acid, ethylenediaminetetraacetic acid, or a combination thereof.

[0431] In a preferred embodiment, suitable nutrients include nitrogen, potassium and phosphorus containing compounds. Suitable nutrients that may be used for facilitating algal growth include sodium nitrate, calcium chloride hydrate (CaCh^H^O), magnesium sulfate (MgSCU’VEhO), dipotassium phosphate, sodium chloride, sodium bicarbonate, potassium hydroxide, ferric sulfate (FeSO4*7H2O), ethylenediaminetetraacetic acid, boric acid, zinc sulfate (ZnSO4*7H2O), or the like, or a combination thereof.

[0432] The nutrients are added in an amount of 0.0000001 to 10 wt% based on the weight of the liquid media, the nutrients and the algae.

[0433] Liquid Media

[0434] The liquid media is added to the plurality of microorganisms along with the nutrients to facilitate growth and reproduction of the microorganisms to form the microorganism package. The liquid media is preferably an aqueous media. Other non-aqueous liquids may also be used to facilitate growth of the microorganisms. The non-aqueous liquids may be compatible with the aqueous media or may not be compatible with the aqueous media.

[0435] In a preferred embodiment, the liquid media is water. The water may include fresh water, brackish water or seawater. Other organic liquids such as alcohols may be added to the mixture of microorganisms and nutrients. Examples of suitable alcohols include ethanol, propanol, butanol, and the like, or a combination thereof.

[0436] The liquid media is added in an amount of 90 to 99.99999 wt%, based on the weight of the liquid media, the nutrients and the microorganisms. The weight of the liquid media, the nutrients and the microorganisms is also referred to herein as the weight of the bio-mineralized microorganism package prior to the drying (desiccation).

[0437] As noted above, the bio-cement obtained after desiccation is further mixed with additional materials (collectively termed an “aggregate”), a substrate (also termed a scaffold) and a second liquid medium to form a wet bio-concrete. The bio-concrete may then be used in the construction of structures, bridges, roads, homes, commercial buildings, and so forth. The bioconcrete after removal of the second liquid medium is called dried bio-concrete. The dried bioconcrete is also referred to herein as a bio-concrete composition.

[0438] The aggregate may contain a natural pozzolan (an amorphous aluminum silicate), a biochar, a silica fume, three-quarter minus rock or smaller, oolitic aragonite, sand, an alkali activator, or a combination thereof. The aggregate is mixed with the bio-cement to form the bioconcrete.

[0439] The pozzolan comprises silicon dioxide and aluminum oxide. Silicon dioxide is present in an amount of 65 to 80 wt%, based on a total weight of the pozzolan. Aluminum oxide is present in an amount of 5 to 15 wt%, based on a total weight of the pozzolan. Iron oxide may be present in an amount of 0.05 to 1.6 wt%, based on a total weight of the pozzolan. The pozzolan may also contain water in an amount of 1 to 8 wt%, based on a total weight of the pozzolan. The pozzolan is present in the aggregate in an amount of 4 to 12 wt%, preferably 6 to 10 wt%, based on the weight of the dried bio-concrete.

[0440] Dried bio-concrete is that obtained after the removal of all liquid media. The dried bioconcrete referred to herein for purposes of determining the weight percent contribution is obtained by the removal of water (which is primarily the liquid media used in the mixing of the bio-cement with the aggregate to produce the bio-concrete).

[0441] Biochar is a type of charcoal that is produced through the pyrolysis of organic materials, such as agricultural waste, wood chips, or other biomass. Pyrolysis is a process where organic materials are heated in the absence of oxygen, which permanently fixes carbonaceous compounds into a stable char. As a result, biochar is created along with other byproducts like gases and liquids. Biochar is considered a form of carbon sequestration, as the carbon captured during the growth of the biomass is retained in the biochar. Biochar production can be a way to utilize organic waste materials that might otherwise be disposed of such as agricultural residues or forestry byproducts. Biochar is characterized by its porous carbon content (that has a high surface area) with possible metal oxide inclusions. Biochar may act as a densifier as well as a binder when it contains metal oxides that react with water. It can also act as a carbon sink. The pyrolytic products (such as biochars and bio-ashes) may comprise about 30 to 40 wt% carbon with the rest comprising a variety of different oxides.

[0442] The biochar may be used in the bio-concrete in an amount of 0.5 to 4 wt%, 1 to 3 wt%, based on a total weight of the dried bio-concrete.

[0443] Silica fume, also known as micro- silica, is a byproduct of the production of silicon metal and ferrosilicon alloys. It is an extremely fine amorphous powder composed of spherical particles that are approximately 100 times smaller than a grain of cement. Silica fume is rich in silicon dioxide (SiCh) and is produced during the reduction of high-purity quartz with coal or coke in electric arc furnaces.

[0444] Silica fume contributes to increased compressive and flexural strength of the bioconcrete. It enhances the durability of concrete by reducing permeability, making it less susceptible to chloride ion penetration and other environmental factors. Silica fume can improve the workability of bio-concrete, although its use may require adjustments to the mix design. Bioconcrete containing silica fume exhibits improved resistance to chemical attacks.

[0445] Silica fume particles used in bio-concrete have an average particle diameter in the range of 0.1 to 0.15 micrometers. The silica fume is used in the bio-concrete in an amount of 0.5 to 4 wt%, 1 to 3 wt%, based on a total weight of the dried bio-concrete.

[0446] “Three-quarter minus rock” refers to a specific size of crushed rock or gravel particles. The term is commonly used in the construction and landscaping industry to describe the size of the material. The “three-quarter minus” designation usually indicates that the crushed rock particles are small and will pass through a screen or sieve with openings that are approximately three-quarter inch in diameter. This means that the material is relatively fine, with particles smaller than 3 / 4 inch. The term “minus” implies that the material includes particles smaller than the specified size. In the case of “three-quarter minus,” this means that the majority of the material will pass through a three-quarter-inch sieve, but it may also contain smaller particles, such as fines, which contribute to the compaction of the material. The rock selected for use herein will be three-quarter minus rock or smaller, such as, for example, quarter minus rock. In the case of “quarter minus,” this means that the majority of the material will pass through a quarter-inch sieve, but it may also contain smaller particles, such as fines, which contribute to the compaction of the material.

[0447] The three-quarter minus rock (or smaller sizes) is used in an amount of 5 to 30 wt%, 23 to 28 wt%, based on a total weight of the dried bio-concrete.

[0448] Oolitic aragonite refers to a form of aragonite, which is a crystal form of calcium carbonate (CaCOa), a mineral commonly found in nature. The term “oolitic” refers to the characteristic small, rounded structures called ooids that make up the material. The oolit ic aragonite may be referred to as the second binder. In an embodiment, the first binder is the same as the second binder. As noted above, the calcium carbonate generated during biomineralization is the first binder.

[0449] The oolitic aragonite (the secondary binder) is present in an amount of 0.5 to 3 wt%, based on the total weight of the dried bio-concrete.

[0450] The sand is used as the substrate (also referred to herein as the scaffold). The sand is generally used in the bio-concrete in an amount of 40 to 65 wt%, based on a total weight of the dried bio-concrete.

[0451] The alkali activator functions to convert the inert calcium carbonate to a reactive calcium hydroxide. Examples of alkali activators include alkali hydroxides, such as for example NaOH; non-silicate weak acid salts, such as for example, sodium sulfate; silicate salts, such as, for example sodium silicate.

[0452] The bio-cement after drying is added to the aggregate to form the bio-concrete. The biocement is present in the dried bio-concrete in an amount of 1 to 20 wt%, preferably 2 to 15 wt%, and more preferably 3 to 10 wt%, based on a total weight of the dried bio-concrete.

[0453] In an embodiment, polymeric fibers may optionally be added to the dried bio-concrete. The polymeric fibers preferably comprise synthetic polymeric fibers. Synthetic polymeric fibers are human- made and created through chemical processes, often involving petroleum-based chemicals or other synthetic substances. They do not naturally occur in the environment. Synthetic polymeric fibers include those derived from a polyolefin, a polyester, a polyamide, a polyaramid, a polyamideimide, a polyarylate, a polyurethane, a polysiloxane, a polyarylsulfone, a polyethersulfone, a polyphenylene sulfide, a polysulfone, a polyimide, a polyetherimide, a polytetrafluoroethylene, a polyetherketone, a polyether ether ketone, or a combination thereof. It is to be noted that the dried-bio-concrete may be devoid of synthetic polymers.

[0454] In an embodiment, in one manner of manufacturing the bio-concrete, the sand and quarter minus rock are taken in the desired proportions and mixed in a blender (e.g., Waring blender, Henschel mixer, and the like) at room temperature for 1 to 10 minutes to form a first mixture.

[0455] The natural pozzolan, a biochar, a silica fume, quarter minus rock, oolitic aragonite, sand, an alkali activator and the bio-cement are added to a blender (e.g., Waring blender, Henschel mixer, and the like) that contains the first mixture. The mixing is conducted at room temperature for 1 to 10 minutes to form a second mixture.

[0456] The second liquid medium (e.g., water) is then added to the blender and mixed for 5 to 15 minutes to form a wet bio-concrete. The wet bio-concrete may be poured into a mold having the shape of a desired article and is then subjected to curing. The wet bio-concrete is then cured at a temperature of 10 to 125°C and 25 to 95 % relative humidity for 1 to 72 hours followed by storage at ambient conditions for 1 to 56 days. During the formation of the article, the second liquid added may optionally reactivate the microorganisms, which can consume some of the binder or nutrients. The microorganism(s) upon reactivation produce the binder (calcium carbonate, reaction products thereof, or the like) to bond the substrates and reinforcing agents into a shapeable solid. The bio-concrete may then be placed in a mold or injected into a mold to form bricks, cinder blocks, columns, tiles, and so on.

[0457] In an embodiment, once the bio-concrete has cured, the bacteria no longer produce the binder. The formulator or user, however, can restore the microbiological activity of the building material by adding sufficient moisture and / or physical conditions to promote activity. In this way any surface imperfections formed during casting of the material, for example, into bricks, can be repaired after curing. This allows for reinforcement of the material to achieve the added strength that the cured material possesses. In this way cracks or fissures which have formed can be filled by the existing microorganisms using the existing matrix elements and nutrient medium.

[0458] Another embodiment of the disclosure is directed to compositions and structures that do not require formworks (e.g., frameless manufacturing) wherein structures are formed by compressing the dry composition after the addition of water (which functions as an activating agent). Preferred compression devices include hydraulic presses and preferred pressures are 100 psi or greater, 250 psi or greater, 500 psi or greater, 1000 psi or greater, 2000 psi or greater, 3000 psi or greater, 4000 psi or greater, 5000 psi or greater.

[0459] Preferred components of the disclosure include all the aforementioned components to form calcium carbonate structures in the form of a sludge or paste. The compaction device compresses the components with added pressure into a form that is maintained and dries without significant alterations of the resulting form. The compressed form can be generated rapidly from a thick slurry or sludge and maintains its shape during calcite formation. Preferably calcite formation is accomplished in vapor chambers (e.g., at greater than ambient pressures) that contain increased vapor pressures or are sprayed or misted, wherein the vapor, mist or spray preferably comprises nutrients or chemical substrates. Preferred forms include blocks, bricks, thin bricks, manufactured or cultured stone, pavers, panels, or any useful structure.

[0460] The bio-cement and bio-concrete and the method of manufacturing the bio-concrete are exemplified by the following non-limiting examples.

[0461] Example

[0462] This example was conducted to demonstrate one exemplary embodiment of a method to manufacture the bio-concrete described herein.

[0463] The bio-cement manufactured as detailed above mixed with an aggregate to form a bioconcrete. The bio-concrete composition is shown in the table below. Table

[0464] As noted above, the sand and quarter minus rock are first mixed together to form a first mixture. The pozzolan, bio-cement, biochar, silica fume, oolitic aragonite and alkali activator are added to the first mixture and blended to form a second mixture. Water (the second liquid media) is then added to the second mixture and blended for additional time to form the wet bioconcrete.

[0465] The wet bio-concrete is then poured into a mold and cured to form the dried bio-concrete. The block is cured at 10 to 125 °C and 25 to 95 % relative humidity for 1 to 72 hours then stored under ambient conditions for 1 to 56 days.

[0466] While the invention has been described with reference to some embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.

Claims

What is claimed is:

1. A bio-concrete composition comprising: a bio-cement; where the bio-cement comprises a bio-mineralized algae, a silica source, pozzolan, biochar and / or bioash; and an aggregate; where the aggregate comprises a secondary binder, sand and / or rock.

2. The bio-concrete composition of Claim 1, where the bio-cement further comprises an alkali activator and where the aggregate further comprises a three-quarter minus rock or smaller, and oolitic aragonite.

3. The bio-concrete composition of Claim 2, where the bio-mineralized algae comprises a primary binder; where the primary binder has the same chemical composition as the secondary binder.

4. The bio-concrete composition of Claim 3, where the primary binder and the secondary binder each comprise calcium carbonate.

5. The bio-concrete composition of Claim 1, where the pozzolan comprises silicon dioxide, aluminum oxide and iron oxide and where the pozzolan is present in the bio-concrete composition in an amount of 4 to 12 wt%.

6. The bio-concrete composition of Claim 5, where the silicon dioxide is present in an amount of 65 to 80 wt%, aluminum oxide is present in an amount of 5 to 15 wt%, and iron oxide is present in an amount of 0.05 to 1.6 wt%, based on a total weight of the pozzolan.

7. The bio-concrete composition of Claim 2, where the three-quarter minus rock or smaller is present in an amount of 5 to 50 wt%, based on a total weight of the bio-concrete composition.

8. The bio-concrete composition of Claim 7, where the three-quarter minus rock or smaller is present in an amount of 23 to 28 wt%, based on a total weight of the bio-concrete composition.

9. The bio-concrete composition of Claim 1, where the sand is present in an amount of 40 to 65 wt%, based on a total weight of the bio-concrete composition.

10. The bio-concrete composition of Claim 1, where the biochar is present in an amount of 0.5 to 4 wt%, based on a total weight of the bio-concrete composition.

11. The bio-concrete composition of Claim 1, where the bio-mineralized algae extract carbon dioxide from the atmosphere.

12. A method of manufacturing a transportable dry composition comprising: blending together a microorganism package; a nutrient; and a first liquid media; activating the microorganism package; subjecting the microorganism package to desiccation to form a bio-mineralized algae; mixing the bio-mineralized algae with a silica source, pozzolan, biochar and / or bioash to form a bio-cement; and mixing the bio-cement with an aggregate to form a bio-concrete.

13. The method of Claim 12, wherein the bio-cement is formed at a first site and where the bio-concrete is formed at a second site different from the first site.

14. The method of Claim 13, further comprising pouring the bio-concrete into a mold to form an article.

15. The method of Claim 13, further comprising curing the bio-concrete.

16. The method of Claim 15, where the curing of the bio-concrete is conducted at a temperature of 30 to 125°C and 25 to 95 % relative humidity for 1 to 72 hours.

17. The method of Claim 16, further comprising mixing the bio-concrete with polymeric fibers.

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