Engineered biochar, manufacturing systems, and methods of making the engineered biochar

Abstract

An engineered biochar (150) comprising a plurality of particles (162), each particle (162) comprising hydrogen atoms (152), oxygen atoms (153), carbon atoms (154), and ash (156) comprising one or more than one nutrient atom. The engineered biochar (150) has a pH of 1 to 8.5; an electrical conductivity of 0.01 dS / m to 4.95 dS / m, the electrical conductivity measured with a 1:10 method of engineered biochar to water; a soluble salt content of 0.01% to 3% of the total dry mass of the engineered biochar; an ash content of 10% to 50% of the total dry mass of the engineered biochar; and a hydrogen to organic carbon molar ratio of 0.1 to 0.7.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to U.S. Provisional Patent Application No. 63 / 569,824, filed March 26, 2024, entitled “Post-processing of raw biochar into carbosoil – a soil improvement technique for alkaline sandy soils,” the disclosure of which is incorporated herein by reference in its entirety. Background of the Invention Technical Field

[0004] The embodiments of the subject matter disclosed herein generally relate to compositions of engineered biochar, systems for preparing said engineered biochar (EB), and methods for preparing said compositions, and more particularly, to the preparation of engineered biochar for alkaline sandy soils.

[0005] Background Technology Discussion

[0006] Sandy soils dominate much of the Arabian Peninsula and the landscape of the Middle East and North Africa (MENA), particularly the vast deserts. These soils are characterized by their coarse texture, low organic matter content, and poor water retention, making them naturally less fertile for agriculture. Due to the extremely arid climate, these soils are also susceptible to erosion and have limited capacity to support conventional agriculture without significant improvements. However, their high permeability allows for rapid drainage, which can be beneficial in areas where irrigation is applied, preventing waterlogging.

[0007] Despite these limitations, sandy soils in some areas of these regions, such as in Saudi Arabia, are used in modern agriculture, where advanced irrigation techniques such as drip irrigation and hydroponics enable the cultivation of crops such as dates, wheat, and vegetables. Furthermore, sandy areas are used for livestock grazing, particularly for camels and sheep, which are well adapted to arid conditions. In urban environments, sandy soils serve as the foundation for construction projects, including roads, buildings, and infrastructure, and engineered solutions are employed to mitigate the impact of shifting sands.

[0008] In recent years, there has been increasing attention paid to land reclamation and desert greening projects to combat desertification and improve soil fertility. Techniques for adding biochar, clay, or organic matter to sandy soils have been tested to enhance water retention and support plant growth. Raw biochar typically has a high pH (above 9, up to 12) and high soluble salt content (above 3% by mass, possibly reaching 10% or more). These characteristics limit their application in alkaline soils common in arid regions such as Saudi Arabia and Mena, as they would further increase the pH and salt content of alkaline soils, which is detrimental to many plants. Most conventional biochar derived from low-density biomass (e.g., chicken manure, cow manure, palm waste, landscaping waste) exhibits these undesirable properties.

[0009] Efforts to improve soil using biochar have focused on enhancing soil water retention and nutrient retention capacity. However, the high alkalinity and high soluble salt content of untreated raw biochar, referred to herein as "salinity," inhibits plant development when applied to alkaline soils at concentrations exceeding 0.1% by mass (or approximately 5 tons / ha below the 30-cm soil layer). Raw biochar can be particularly detrimental to plant development in high-end applications such as landscaping, horticulture, or vegetable cultivation, where doses can be as high as 30% or even 100%. Furthermore, alkaline soils reduce the plant availability of most nutrients by significantly decreasing their solubility and, in the case of nitrogen, by volatilization (i.e., ammonia volatilization loss). These issues currently hinder the development of the biochar industry in regions with alkaline sandy soils.

[0010] Therefore, there is a need for engineered biochar that avoids the above problems and can be easily and cheaply manufactured on a large scale. Summary of the Invention

[0011] According to one embodiment, there exists an engineered biochar comprising a plurality of particles, each particle comprising hydrogen atoms, oxygen atoms, carbon atoms, and ash containing one or more nutrient atoms. The engineered biochar has: a pH of 1 to 8.5; an electrical conductivity of 0.01 dS / m to 4.95 dS / m, measured by a 1:10 ratio of engineered biochar to water; a soluble salt content of 0.01% to 3% of the total dry mass of the engineered biochar; an ash content of 10% to 50% of the total dry mass of the engineered biochar; and a hydrogen to organic carbon molar ratio of 0.1 to 0.7.

[0012] According to another embodiment, a biochar treatment unit is provided, configured to remove soluble salts to produce engineered biochar. The biochar treatment unit includes N stages (i) having N reactors (Ri), where N is a positive integer, the N reactors (Ri) being fluidly connected in series and configured such that raw biochar enters a first reactor among the N reactors and passes sequentially as a slurry (Si) through the remaining reactors to become the engineered biochar upon exiting the Nth reactor, and freshwater (FW) flows into the Nth reactor and removes soluble salts from each of the remaining reactors, exiting the first reactor as brine (SW). Each stage (i) includes a conveyor (Ci) configured to remove the slurry (Si) from the reactor (Ri); and a solid-liquid separator (SLSi) configured to receive the slurry (Si) from the conveyor (Ci), separate the treated biochar from the slurry (Si), and move the treated biochar to the next reactor (R(i+1)).

[0013] According to another embodiment, there is a method for preparing engineered biochar, the method comprising feeding raw biochar into a current reactor, feeding brine from a next reactor into the current reactor, removing washed biochar from the current reactor, and separating the washed biochar from the brine to obtain the engineered biochar. The engineered biochar has: a pH of 1 to 8.5; an electrical conductivity of 0.01 dS / m to 4.95 dS / m, the conductivity being measured using a 1:10 ratio of engineered biochar to water; a soluble salt content of 0.01% to 3% of the total dry mass of the engineered biochar; an ash content of 10% to 50% of the total dry mass of the engineered biochar; and a hydrogen to organic carbon molar ratio of 0.1 to 0.7. Brief description of the attached figures

[0014] To gain a more complete understanding of the invention, reference is now made to the following description taken in conjunction with the accompanying drawings, wherein:

[0015] Figure 1 This is a schematic diagram of equipment used to manufacture engineered biochar from biomass waste;

[0016] Figure 2 schematically shown Figure 1 The biochar treatment unit of the equipment;

[0017] Figure 3 Based on Figure 2 A flowchart of a method for preparing the engineered biochar using a biochar treatment unit;

[0018] Figure 4 schematically shown Figure 2 The two reactors of the biochar treatment unit;

[0019] Figure 5 Schematic illustration of as Figure 2 A solid-liquid separator module, which is part of the reactor of the biochar treatment unit;

[0020] Figure 6 schematically shown Figure 2 Various other components of the reactor in the biochar treatment unit;

[0021] Figure 7 schematically shown Figure 1 The biochar treatment unit comprises six reactors that are operatively connected in series.

[0022] Figure 8 Various primitive biochars and their uses were drawn. Figure 2 pH versus salinity of engineered biochar produced by a biochar treatment unit;

[0023] Figure 9 It is shown in Figure 2 A graph showing the biochar salinity and water salinity after each stage in the biochar treatment unit.

[0024] Figure 10 It is a graph showing the salinity and pH of biochar versus time when acid is added in one or more stages;

[0025] Figure 11A It shows the use of Figure 2 Defined parameters for engineered biochar produced by a biochar processing unit;

[0026] Figure 11B It shows the use of Figure 2 Secondary parameters of engineered biochar produced by the biochar processing unit;

[0027] Figure 11C It shows the use of Figure 2 Nutrient atoms in engineered biochar produced by the biochar processing unit;

[0028] Figure 12 A vertical tower process for manufacturing engineered biochar using an alternative biochar processing unit is shown.

[0029] Figure 13 This demonstrates another vertical tower process for manufacturing engineered biochar using yet another biochar processing unit;

[0030] Figure 14 The study demonstrated an increase in the dry weight of acacia plants treated with the engineered biochar and other conventional soil conditioners;

[0031] Figure 15 The study showed an increase in the basal circumference of the trunks of acacia plants treated with the engineered biochar and other conventional soil conditioners.

[0032] Figure 16 The study showed an increase in the basal trunk circumference of other plants (Ziziphus spina-christi) treated with the engineered biochar and other conventional soil conditioners; and

[0033] Figure 17 The study showed an increase in trunk diameter in olive trees treated with the engineered biochar and other conventional soil conditioners.

[0034] Detailed description of the invention

[0035] The following description of the embodiments refers to the accompanying drawings. The same reference numerals in different drawings identify the same or similar elements. The following detailed description does not limit the invention. Rather, the scope of the invention is defined by the appended claims. For simplicity, the following embodiments relate to a biochar treatment unit comprising six reactors. However, the embodiments discussed below are not limited to six reactors but can be applied to units with fewer reactors.

[0036] Throughout this specification, the phrase "in one embodiment" means that a particular feature, structure, or characteristic described in connection with one embodiment is included in at least one embodiment of the disclosed subject matter. Therefore, the phrase "in one embodiment" appearing throughout this specification does not necessarily refer to the same embodiment. Furthermore, a particular feature, structure, or characteristic may be combined in any suitable manner in one or more embodiments.

[0037] According to one embodiment, a novel engineered biochar is produced via a novel multi-stage, washing, and treatment method that reduces the pH of the biochar to levels below 8.5, or even below 7, and also reduces its salinity to below 3% by mass (and preferably below 1% or below 0.3% for high-end applications). This novel engineered biochar composition enables the use of biochar in areas where long-term soil enhancers are most needed, such as the ultra-arid Saudi Arabian desert and the MENA region and beyond. In another embodiment, the engineered biochar allows for the use of biochar at high concentrations without the risk of harming plants. The engineered biochar has been shown to produce significant plant enhancement effects, as demonstrated by several greenhouse and field trials (discussed later). The engineered biochar has the potential to replace environmentally damaging peat moss in greening projects in the Saudi Arabian and MENA regions.

[0038] The system (apparatus) for preparing the engineered biochar will now be discussed with reference to the accompanying drawings. Figure 1The various modules of the biochar treatment system 100 are schematically shown. Biomass waste 110 is received by the system 100 and carbonized in the carbonization module 120. Biomass waste 110 may include animal manure, plant parts, fruit parts, food waste, etc. In one embodiment, carbonization involves a pyrolysis process. Pyrolysis is the thermal decomposition of materials in the absence of oxygen or under extremely low oxygen conditions. It breaks down complex molecules into simpler gaseous, liquid, and solid residues by applying heat, typically between 200°C and 900°C, depending on the material and desired products. Low or no oxygen prevents combustion and allows the biomass waste 110 to decompose into new compounds. As a result of the pyrolysis process, gases, liquids, and solids are formed. Therefore, a separation unit 130 is used to separate these phases. The gaseous phase may include CO, CO2, H2, CH4, and other hydrocarbons. The liquid phase may include condensable hydrocarbons and tar-like substances. The solid phase may include carbon-rich residues, also known as raw biochar. The raw biochar is separated from the other phases and processed in the biochar treatment unit 140 to produce engineered biochar 150.

[0039] The engineered biochar 150 produced using the biochar treatment unit 140 was found to include hydrogen atoms 152, oxygen atoms 153, carbon atoms 154, ash 156 containing one or more nutrient atoms (inorganic atoms), trace amounts of soluble salts 158, and insoluble or poorly soluble salts 160. In this study, poorly soluble salts are considered to be salts with a solubility in water below approximately 2 g / L. Hydrogen atoms 152, oxygen atoms 153, carbon atoms 154, ash 156, and insoluble or poorly soluble salts 160 can form particles 162, such as... Figure 1 The above is schematically illustrated. Some of these particles may also include soluble salts 158. In one embodiment, each particle 162 includes trace amounts of soluble salts 158, for example, less than 1% by mass. The soluble salts 158 are largely removed after treatment in the biochar treatment unit 140, as referenced below. Figure 2 The various characteristics of engineered biochar 150 discussed later, and their properties in... Figures 11A to 11C As shown in the diagram, the main energy source for the pyrolysis process can come from the biomass itself by generating syngas, thus allowing the carbonization process to be energy-sufficient.

[0040] For details regarding the biochar treatment unit 140, please refer to the following attached diagrams for discussion. Figure 2 One possible implementation of the unit is shown. The biochar treatment unit 140 may include multiple (N) independent continuous stirred tank reactors (CSTRs). Although Figure 2 The diagram shows N=6 CSTRs, but fewer or more reactors can be used. In one application, only two reactor CSTRs are used. In another application, only three reactor CSTRs are used. Figure 2Each reactor CSTRi in the diagram is associated with a conveyor Ci and a solid-liquid separator SLSi, where "i" is a positive integer referring to a specific reactor "i". In the described embodiment, i takes any value from 1 to 6. Although Figure 2 The conveyor Ci and separator SLSi are shown located outside the reactor CSTRi, but as discussed later, these elements can be placed on, inside or outside the reactor, or both.

[0041] Now for reference Figure 2 configuration and Figure 3 The method 300 shown discusses the operation of the biochar treatment unit 140. In step 302, the biochar from the carbonization module 120 (see...) Figure 1 The obtained raw biochar 210, mass MB1, is fed into the first reactor CSTR1. This mass includes a given mass of soluble salt MS1, for example, about 6% of MB1 (MB1 is the total mass of the raw biochar 210 to be processed). Brine SW2 from the second reactor CSTR2 is fed into the first reactor CSTR1 in step 304 to wash the biochar mass MB1. Brine SWi from each reactor is provided to the preceding reactor to wash soluble salts from the biochar in that preceding reactor. In one embodiment, brine SWi may include fresh water and a certain amount of soluble salts already removed from one or more of the N reactors. Note that the initial fresh water FW is supplied to the last reactor CSTR6. This fresh water FW is then supplied as brine SW6 to reactor CSTR5 after washing some soluble salts from the last reactor CSTR6, and so on. Therefore, the saltiest SWi is the brine at the first reactor CSTR1. Before being discharged to the previous reactor or for cleaning, the brine SWi can be recirculated through reactor CSTRi using a pump or agitator, which will be discussed later.

[0042] In step 306, reflux water BFW1 is provided to the first reactor CSTR1. Reflux water BFW1 is generated by the first solid-liquid separator SLS1 when it separates the washed biochar from the first reactor from the brine. In step 308, the first conveyor C1 removes the washed biochar from the first reactor CSTR1 and supplies it to the first separator SLS1 in step 310. If the washed biochar has not yet reached the desired characteristics, the method determines in step 312 to provide partially washed biochar to the next reactor and repeats steps 302 to 310. In one embodiment, each reactor CSTRi has the same structure as the first reactor CSTR1, i.e., reactor CSTRi includes conveyor Ci, separator SLSi, etc. In this embodiment, the washed biochar MB2 after water separation is supplied to the second reactor CSTR2, and the above process is repeated for each reactor. However, if the treated biochar has reached the desired characteristics (producing engineered biochar 150), the engineered biochar is packaged and shipped to various customers in step 314. The resulting brine SW1 from the first reactor CSTR1 can then be fed to a water desalination unit for processing. Note that all other brine SWi from subsequent reactors is fed to the preceding reactor; for example, brine SW5 from the fifth reactor CSTR5 is fed to the fourth reactor CSTR4, and so on. This means that the brine SWi flows from the last reactor toward the first reactor (by gravity, as discussed below), while the partially washed biochar (also referred to herein as slurry Si) flows from the first reactor toward the last reactor. Note that slurry is a mixture of high-density solids suspended in a liquid (typically water). Slurry is formed when biochar is stirred with water within CSTRi. In SLSi, the slurry is separated into solid and liquid components; the water is discharged (BFWi), and the biochar (MBi) carries a significant amount of water (approximately 60% water) and some salt into the next reactor, but it is in a moist solid form.

[0043] Note that inside the conveyor (Ci), the mixture is still in slurry form. Therefore, it is correct to refer to the flows inside the conveyor as Si in the diagram.

[0044] As the slurry Si moves from one stage to another (e.g., from one reactor to another), it has less and less soluble salt, and the brine becomes saltier as it travels from the last reactor toward the first reactor.

[0045] The cycle described above for the first reactor CSTR1 (i.e., steps 302 to 310 for each stage of unit 140) may include an optional step 316, namely, injecting additional material AS into the reactor to lower the pH of the partially washed biochar. Although Figure 2The embodiment shown depicts no additional substance AS being added to the first reactor, but the same figure illustrates the addition of acid PA to the second reactor, further addition of PA acid to the third reactor, additional addition of PA acid to the fourth reactor, no addition to the fifth reactor, and the addition of additional substance AS to the sixth reactor. In the embodiment, PA acid is phosphoric acid (H3PO4). However, in other embodiments, hydrochloric acid (HCl), sulfuric acid (H2SO4), and / or other acids may be used. PA acid is added to neutralize and dissolve low-solubility bases with moderate pH, such as calcium carbonate and magnesium carbonate, and to further reduce the pH and soluble salt content in the biochar mass. Note that the output of each reactor CSTRi shows the biochar mass MBi, which decreases as i increases. The figure also shows the salt mass MSi at the output of each reactor CSTRi, which decreases (e.g., halved) in each cycle as i increases. Although Figure 2 The diagram illustrates the addition of acid PA at a selected reactor and the addition of additional substance AS at the last reactor, but acid PA can be added to any reactor. The same applies to adding AS.

[0046] The increase in salt in the brine and the decrease in salt in the treated biochar are due to the introduction of freshwater FW at the last reactor, CSTR6 in this embodiment, and the brine SW6 from that reactor being provided to the fifth reactor, and the brine SW5 from the fifth reactor being provided to the fourth reactor, and so on. Thus, the cleanest water FW is provided to the last reactor in the chain, and the saltiest water SW1 is extracted to the first reactor. This arrangement is effective because the biochar at the first reactor has the highest salt content, therefore the salt concentration of the brine SW2 received by the first reactor needs to be lower than the salt concentration of the biochar MB1 in the first reactor. The same applies to the other reactors; that is, the salt concentration of the brine received by any reactor CSTRi needs to be lower than the salt concentration of the biochar in reactor CSTRi in order to wash some salt from the biochar MBi.

[0047] Figure 2 The biochar treatment unit 140 shown and Figure 3 The method shown is characterized by the countercurrent flow of biochar slurry Si and brine SWi. More specifically, freshwater FW is injected at the last reactor CSTR6, and the saltiest water SW1 is discharged from the first reactor, meaning the brine SWi travels from the last reactor to the first reactor. Conversely, an initial mass of biochar (with high pH and the highest soluble salt concentration) is first injected into the first reactor and then travels towards the last reactor.

[0048] Regarding the salt concentration in biochar materials, for Figure 2In the illustrated embodiment, the initial salt concentration (entering the first reactor) is approximately 7% by mass, and the final salt concentration (leaving the sixth reactor) is approximately 0.12% by mass. The salt concentration entering the second reactor is approximately 3.5% by mass. The salt concentration entering the third reactor is approximately 1.79% by mass. The salt concentration entering the fourth reactor is approximately 0.92% by mass. The salt concentration entering the fifth reactor is approximately 0.47% by mass. In a given reactor CSTRi, the reaction time Ti between the biochar mass MBi (or slurry Si) and the brine SW(i+1) from the next reactor is approximately 90 minutes in the illustrated embodiment. In another embodiment, the reaction time can be from 30 minutes to 72 hours. In yet another embodiment, the reaction time can vary from one reactor to another (e.g., T1 > T2 > T3 > … > T6). In the illustrated embodiments, the term "salt" is understood to mean any soluble salt, i.e., salt dissolved in water. Examples of soluble salts include sodium chloride (NaCl), potassium nitrate (KNO3), ammonium sulfate ((NH4)2SO4), and lithium bromide (LiBr). More generally, any salt of Group 1 metals, nitrates, acetates, perchlorates, and ammonium salts are considered soluble salts. Insoluble salts, typically derived from Group 2 metals, include calcium sulfate (CaSO4), calcium carbonate (CaCO3), magnesium carbonate (MgCO3), and silver chloride (AgCl). Therefore, in this document, the term soluble salt refers to one or more of the aforementioned salts that are soluble in water. Since some soluble salts are naturally soluble in water, no additional material is added to the first reactor, as one objective is to remove any potentially soluble salts by washing the biochar material with water. However, some salts, typically derived from Group 2 metals, such as calcium carbonate (CaCO3), magnesium carbonate (MgCO3), and Group 2 metal sulfates and phosphates, can become more soluble by reacting with acids and thus be washed away. For this reason, PA acid is added only in the second and / or third reactors, and not in the first reactor.

[0049] In other words, Figure 3The method described includes a primary stage (i.e., using a first reactor CSTR1) for washing and leaching with water alone to remove high-pH soluble alkalis (e.g., potassium carbonate pH 11.5, potassium / calcium oxide pH 12.5). The method then includes two or more secondary stages (i.e., using a second reactor CSTR2 and optionally a third reactor CSTR3) that include additional water washing and leaching, aided by the application of acid solutions (e.g., hydrochloric acid, sulfuric acid, and / or phosphoric acid, etc.) to neutralize and dissolve low-soluble alkalis of moderate pH, such as calcium carbonate and magnesium carbonate, and further reduce the pH and soluble salt content of the biochar. For higher-quality engineered biochar 150, one or more tertiary stages (e.g., using a fourth reactor CSTR4) may be added to fine-tune product specifications through water leaching with the aid of acid and optionally nutrient or chemical enrichment or the addition of a mixture of beneficial microorganisms (additional substances AS).

[0050] use Figure 3 In the discussion and Figure 2 The multi-stage process illustrated here maximizes the use of acid for neutralizing soluble salts and reduces total water consumption. Each stage removes a portion of the ash component, as the ash component contains soluble salts and has a high pH. The high pH of biochar is caused by the ash content naturally present in the original biochar, especially in those produced from low-density biomass and in industrial processes that inevitably undergo partial combustion due to the presence of some air in the reaction zone. Ash consists of several salts, oxides, and hydroxides, which increase the pH of the biochar. The soluble portion of the ash also contributes to the salinity of the biochar. Therefore, Figure 3 The method uses multiple stages of water and acid solutions to selectively remove those ash components up to a specified pH and salinity range.

[0051] Figure 3 The process can also be carried out in batches and in several configurations, such as suspension, fixed bed, or slurry. Furthermore, these stages can be combined into fewer or more stages, depending on the water-to-biochar ratio, chemical dosage, mixing within the reactor, reaction time, and flow pattern (countercurrent, cross-flow, or co-current). Figure 2 The stages shown are performed in series. However, the biochar treatment unit 140 can be reconfigured for parallel operation. For such a parallel configuration (not shown), two reactors (similar to CSTR1) can be added in parallel to increase the total residence and reaction time for the individual water removal of high-pH alkali in the first stage. The outputs of these two reactors can then flow into a single CSTR2, followed by one or more CSTR3s. These configurations can be deployed to adjust the residence time within each stage without scaling the reactor size.

[0052] The speed of the conveyor (Ci) can be adjusted to control the solid-to-liquid ratio within each CSTRi.

[0053] For batch configurations, biochar is loaded into tanks. The liquid to solid (water to biochar) mass ratio can be approximately 2:1 or greater. The same water is recirculated through the biochar tank several times. The water is then drained through a filter into an auxiliary tank. Multiple cycles of water or an acidic solution are applied to the same tank, with the water and acid solution being exchanged between each cycle. The aqueous solution from each cycle can be used to treat the biochar in the initial stage. A dilute aqueous solution with acid can be added to minimize the number of cycles. The residence time of the biochar in the tank varies from several hours to several days.

[0054] Return to Figure 2 The continuous operation of the biochar treatment unit 140 shown, and a more detailed view of the reactor CSTRi are shown in [the image / image / etc.]. Figure 4 As shown in the image. Figure 4 For simplicity, only two reactors, CSTRi and CSTR(i+1), are shown, but the same configuration can be implemented for all N reactors in unit 140. In one embodiment, each reactor has the same structure, i.e., they have the same diameter, height, and include the same functional elements. However, in another embodiment, the structure of one reactor may differ from that of the next reactor.

[0055] Figure 4 Each reactor CSTRi is shown to have a tank 400 with an inner cavity 401 that receives a mixer Mi configured to mix the received biochar mass MBi and the received liquid (e.g., brine SW(i+1)) to form a slurry Si. The slurry Si partially fills the inner cavity 401 to a given height Hi. The mixer Mi may include a corresponding electric motor 402 that rotates a corresponding impeller 404. Continuous rotation of the impeller 404 keeps the biochar particles suspended in the brine SWi. The rotational speed of the impeller 404 is selected to prevent the biochar particles from settling to the bottom of the tank 400. The range of impeller rotational speeds depends on the size of the biochar particles, the density of the biochar particles, and / or the size of the reactor.

[0056] Figure 2 and Figure 4 The process shown allows for a counter-current mode, where the brine SWi flows in one direction ( Figure 4 The flow (from right to left) is similar to the flow of biochar slurry Si between the reactors. Figure 2 (From left to right) Conversely. This configuration allows for higher reaction and extraction efficiency as well as better utilization of water and acid resources. In the described embodiment, to prevent the formation of a paste within the reactor, the biochar and water slurry mixture Si is obtained by maintaining a liquid to solid mass ratio of approximately 4:1 or higher.

[0057] Figure 4 The distal portion of conveyor Ci is also shown located within the inner cavity 401 of reactor CSTRi, in direct contact with the slurry Si. The distal portion of conveyor Ci is configured to receive the slurry Si as input. A rotating portion of conveyor Ci (not visible in the figure, also referred to as a screw) pushes the slurry Si upwards into pipe 405 until the slurry reaches the top of tank 400. At this point, the slurry Si exits from pipe 405 and enters separator SLSi through conduit 406. Conveyor Ci includes a motor 408 that rotates the rotating portion to move the slurry Si upwards within pipe 405. Those skilled in the art will understand that for this operation to be successful, the slurry Si needs to have a certain consistency. A paste or a very fluid biochar solution would be very difficult to vertically convey to the top of tank 400 and into separator SLSi.

[0058] In the embodiment described, the separator SLSi includes a sieve 412 that rotates on a fixed base 502 due to a motor 512, such as Figure 5 As better illustrated in the diagram. Inside the sieve 412, there is a screw (or similar element) 510, which is fixed to the sieve and configured to rotate with the sieve to move the slurry Si from reactor CSTRi toward reactor CSTR(i+1) in direction A. The brine from the slurry Si leaves the sieve 412 and is collected on the return tray 514, and the water is... Figure 2 The reflux water BFWi is shown in the diagram. This water returns to tank CSTRi because the return tray 514 is tilted towards tank 400. This means that the water BFWi returns to reactor CSTRi due to gravity. Figure 5 The feed element 516 is shown, which is configured to receive slurry Si from the conduit 406 of the conveyor Ci and deliver the slurry to the screw 510 inside the screen 412.

[0059] Return to Figure 4 It also illustrates a particle settling and reflux PSBi module attached to reactor CSTRi. While the figure shows the PSBi module located outside tank 400, in one embodiment, the PSBi module is partially located inside and partially outside tank 400. For example, Figure 6 The PSBi module is shown to have an internal feed port 610 and an external output port 620. The feed port 610 may include a plate (e.g., made of metal or plastic) 612 that covers an opening 614 formed in the wall of tank 400. The plate 612 forms a pocket 616 that is sealed at the top and open at the bottom, allowing brine SWi from tank 400 to enter the pocket 616 only from the bottom. Figure 6The arrows in the diagram illustrate this. One or more parallel plates 618 may be attached substantially perpendicular to the wall of tank 400 and also perpendicular to plate 610 to reduce turbulence and slow the flow of brine SWi, causing the biochar to settle back into the turbulent area of ​​the slurry (i.e., preventing biochar particles from escaping tank 400). The slurry Si is expected to leave tank 400 via conveyor Ci, rather than through orifice 614. Only the brine SWi is expected to leave through orifice 614 and enter chamber 622 formed in output port 620, as schematically indicated by arrow 624. Note that chamber 622 is open at the top. A removable plate 626 slides within chamber 622 to divide the chamber into two sub-chambers 622A and 622B, for adjusting the liquid level within chamber 622 and thus the slurry level in tank 400. Therefore, the brine SWi is forced from the first sub-chamber 622A over the removable plate 626 into the second sub-chamber 622B. In other words, the removable plate 626 can have different heights, and the reactor operator decides which height to use. The presence of the removable plate 622 also prevents biochar particles from leaving the tank 400. After passing through the plate, the brine SWi exits through the pipe 628 located at the bottom of chamber 622 and proceeds in parallel to the previous reactor CSTR(i-1). Figure 2 (As shown in the diagram). In one embodiment, the removable plates 626 have different sizes, with the smallest (shortest) in CSTR1 and the largest (highest) in the last CSTR. The size of each plate 626 controls the slurry height in each CSTRi. Therefore, the increasing size of the plates 626 from CSTRi to CSTR(i+1) allows the brine SW(i+1) to flow naturally from CSTR(i+1) to CSTRi.

[0060] Figure 6 A feed port 640 is also shown, configured to receive brine SW(i+1) from the next reactor CSTR(i+1). The feed port 640 may include a pipe 642, an orifice 644 formed in the wall of tank 400, and a cover 646 for directing the feed brine SW(i+1) to the bottom of tank 400. The cover 646 also prevents slurry from flowing into port 640, reducing the risk of clogging. In one embodiment, the position of the orifice 644 relative to the bottom of tank 400 is less than the position of the orifice 614 of PSBi. Figures 4 to 6 The structure of the reactor CSTRi shown can be shared by all other reactors in the biochar treatment unit 140.

[0061] The above reference Figures 2 to 6 The reactor under discussion Figure 7The diagram is shown attached to a common frame 702. This figure illustrates a combination of six CSTRs in series, separated by six rotary screen separators SLSi, with a particle settling and recirculation PSBi unit attached inside each tank 400 of each reactor CSTRi. Slurry Si is pumped into the rotary screen separators SLSi via an Archimedes screw on conveyor Ci. Liquid BFWi passing through screen 412 is returned to the same tank, as it may carry particles. Brine SWi and biochar slurry Si from the particle settling and recirculation PSBi unit flow countercurrently. Figure 7 The unit 140 shown also includes at least one acid dispensing module ADMi, configured to dispense a given amount of acid PA stored in tank 710. ADMi may include a pump or valve 712 for dispensing acid PA to the corresponding tank 400. In one embodiment, processor 720 may be wired or wirelessly connected to various motors, pumps, valves, and other components for controlling the flow of slurry, brine, and acid. An additional substance dispensing module 740 may also be present for dispensing AS. The additional substance dispensing module 740 may have a similar structure to ADMi.

[0062] based on Figure 3 The process and shown Figure 2 and Figures 4 to 7 The inventors obtained a biochar treatment unit 140 as shown in the figure, which has the following properties: Figure 8 The engineered biochar composition 150 shows the pH and salinity (where salinity refers to the content of soluble salts, as previously discussed). Figure 8 Also shown is original biochar 210 (i.e., not based on...). Figure 3 The pH and salinity of the biochar treated by the method and unit 140 were analyzed. The pH and salinity of the raw biochar appeared to show a linear relationship between pH 9 and 12.2. This is related to the ash content and type present in the raw biochar, as well as the negative quality of the biochar due to both high salinity and high pH. Figure 8 The properties achieved by engineered biochar 150 (obtained using biochar treatment unit 140) are also shown, namely pH < 8.5 and salinity < 1%.

[0063] Figure 9 A total of three stages are shown as preferred to achieve a biochar salinity (soluble salt by mass, shown as curve 910) below 1%. Curve 912 shows the salinity of the brine SWi after each stage. However, if an even lower salinity is desired for the engineered biochar 150, more stages can be used. Note that stages refer to the use of... Figure 2 or Figure 6 The single CSTRi shown.

[0064] Figure 10The results of two experiments are shown. For the first experiment (see curves B3 1010 (for slurry pH) and 1012 (for biochar BC pH)), the acid PA was added in a single step (i.e., Figure 2 (PA injection of CSTR2). BC pH represents the pH of the biochar or solid after it has been removed from the solution (slurry Si) and subjected to a standard pH measurement (e.g., 1g biochar to 10mL deionized water). Slurry pH is measured in situ while the slurry is being mixed in tank 400.

[0065] For the second experiment (see curves B4 1020 (for BC pH) and 1022 (for slurry pH)), the acid PA was added in two steps (e.g., Figure 2 (PA injection in CSTR2 and CSTR3). For the first step, 1.75% by mass of PA was added, and for the second step, 1.75% by mass of PA was added. It can be seen that the addition of 3.5% by mass of acid (Experiment B3) is sufficient to reduce the pH of the slurry Si to the desired level below 8.5. The total residence time of 1.5 hours per stage is sufficient for neutralization and salt leaching. Separate addition of acid (Experiment B4) has only a local effect and does not affect the final pH. The inventors observed a residual pH rise, which is likely due to the balance between the calcium carbonate present deep inside the pores of the biochar particles and the active sites in the external pores, since the slurry is held in water. A similar reaction is expected to occur with the biochar particles even when applied directly to moist soil. Therefore, it is desirable to neutralize the pH to a level slightly below the target to avoid a pH rebound to a value above the desired limit.

[0066] based on Figure 2 or Figure 7 The engineered biochar 150 obtained by the biochar treatment unit 140 shown has the following characteristics: Figure 11A The table shows the parameters. Note that in the described embodiments, five different parameters 1110 to 1118 characterize engineered biochar 150. These parameters are pH 1110, electrical conductivity 1112, soluble salt content 1114, ash content after combustion 1116, and hydrogen to organic carbon molar ratio (H / Corg) 1118. H / Corg 1118 relates to the stability of engineered biochar 150. Figure 11A It shows a first quality standard (e.g., using) Figure 2 and Figure 7 The first engineered biochar (Column 1120) has three of the six stages shown, and the second engineered biochar (Column 1122) has a second quality standard (e.g., using only two of the six stages). Figure 11AThe last column 1124 of the table shows an example of engineered biochar 150 obtained from chicken manure. In another embodiment, the engineered biochar may be defined by any four of the five parameters described above. In yet another embodiment, the engineered biochar may be defined by any three of the five parameters described above. Note that... Figure 11A The ranges and / or specific values ​​shown in the table for engineered biochar 150 are obtained due to the specific use of the aforementioned unit 140.

[0067] Figure 11B Secondary parameters characterizing engineered biochar 150 are shown. These secondary parameters include bulk density, water holding capacity (WHC) in both mass and volume fractions, cation exchange capacity (CEC), material stability, water content, typical bulk density, specific surface area, total organic carbon, total organic matter, and biochar particle size. Note that the material stability parameter is calculated based on a linear formula, where the independent variable is H / Corg, discussed above. Note that typical values ​​column 1130 shows the range of values ​​for these parameters obtained from various experiments conducted with biochar from various sources and at various treatment stages of unit 140, while engineered biochar column 1132 shows the actual values ​​obtained from a single run of unit 140 with chicken manure biochar. Also note that any of these secondary parameters can be compared with… Figure 11A The parameter combinations shown in the table define the characteristics of engineered biochar 150. In other words, Figure 11A Any three or more parameters in the table can optionally be combined with Figure 11B One or more combinations of secondary parameters in the table are used to define the final engineered biochar 150.

[0068] Figure 11C The diagram illustrates the possible nutrient atoms in engineered biochar 150 when made from chicken manure. When engineered biochar 150 is made from another material, its composition can be relative to... Figure 11C The compositional variation shown is approximately + / - 20%. Besides... Figure 11A In addition to three or more parameters, one or more nutrient atoms shown in the figure can characterize engineered biochar 150. In one embodiment, engineered biochar 150 can be derived from... Figure 11A Three or more parameters Figure 11B One or more parameters shown and Figure 11C It is characterized by one or more nutrients as shown. Note that... Figure 11C The total value column 1140 indicates the percentage range of each nutrient's weight relative to the total weight of the engineered biochar, for example, N is 3% w / w to 5% w / w. The same column 1140 also indicates specific values, such as N being 4.08%, corresponding to a single measurement. Figure 11CThe “Easy to obtain” column 1142 indicates the actual mass of nutrients in mg per kg of engineered biochar 150 (e.g., 802 mg N per kg of biochar), which can be more easily extracted by plant roots.

[0069] Engineered biochar 150 can also be obtained using a modified biochar processing unit 1200 via a vertical column process, such as... Figure 12 As shown in the diagram. In this embodiment, there are N plug flow reactors (PFRi). Figure 12 Two reactors, PFRi and PFR(i+1), are shown. Each reactor PFRi has a conveyor Ci, which can connect to... Figure 4 and Figure 7 The conveyor Ci shown may be the same or different. Conveyor Ci removes slurry Si from the bottom of tank 400 and transfers it to the next tank without solid-liquid separation or with minimal solid-liquid separation. Brine SW(i+1) from the next reactor PFR(i+1) flows to the current reactor PFRi due to gravity or a pump (not shown). Instead... Figure 6 The PSBi module shown can use a mesh filter 1210 to prevent biochar from moving along pipe 1220 to the previous reactor. This vertical process utilizes sedimentation (for removing biochar from the bottom of the tank to the next tank) and gravity separation, or pumps and valves, for moving brine SWi from one tank to the previous tank. Figure 13 An embodiment is shown in which the reactor PFRi is replaced with a CSTRi reactor to achieve another modified biochar treatment unit 1300. The CSTRi reactor is shown to have a mixer Mi. Biochar bed deposits 1310 are shown at the bottom of each tank 400, and a conveyor Ci moves the biochar deposits to the next reactor.

[0070] Effective in all embodiments is the final wastewater (see Figure 2 The SW1 in the solution can be used for reverse osmosis or evaporation. The recovered salt (rich in K, Mg, and / or Ca) can be used as fertilizer. Due to its biomass origin, the sodium content remains low.

[0071] The inventors' experiments using engineered biochar 150 to cultivate various plants in the desert have shown a significant enhancement in biomass growth over several years (in some cases exceeding 60%), such as... Figure 14 The example shown in the middle is acacia field (engineered biochar 150 is made from jujube biochar; 1 kg of biochar is applied to a pit at a depth of 60 cm). Figure 15 The diagram shows the trunk basal circumference of acacia trees when engineered biochar 150 is incorporated into the top 30 cm of soil at different rates from 5 t / ha to 100 t / ha (5 CS to 100 CS). Figure 16The same conditions were shown for *Ziziphus jujuba*. Both experiments demonstrated a significant increase in trunk basal perimeter compared to control soil when 100 CS of biochar was supplied. Figure 17 An experiment was shown in which engineered biochar 150 was incorporated into the top 60 cm of soil at 5.3 kg / plant (CBS) and compared with a control with equivalent fertilization and irrigation, as well as a beneficial microbial mixture (Bact).

[0072] The inventors have discovered that soil properties are improved, such as enhanced water retention and nutrient retention capacity, when engineered biochar 150 is added. At a 1% mass ratio (approximately 5% by volume), the water-holding capacity of sandy soils increases by approximately 11%, while the nutrient retention capacity (CEC) increases by approximately 53%. It has also been found that engineered biochar 150 can be applied not only in agriculture but also in landscaping and revegetation projects, particularly in arid and alkaline soil environments. Its ability to improve soil properties at high application rates without negative side effects, along with its environmental aspects of carbon sequestration, provides a significant improvement over existing soil conditioners such as virgin biochar, compost, or sphagnum peat. In this regard, it is noteworthy that engineered biochar 150 experiences negligible mass (or material) loss after one year, while products based on sphagnum peat or compost may experience more than 81% material loss due to microbial decomposition.

[0073] The term “about” is used in this application to indicate a variation of up to 20% in the parameter characterized by the term.

[0074] Since water or moisture content is always present in biochar, the term "total mass" when referring to the concentration of elements or properties of engineered biochar refers to the total dry mass of engineered biochar, without regard to water or moisture content.

[0075] It should be understood that although the terms first, second, etc., may be used herein to describe various elements, these elements should not be limited by these terms. These terms are used only to distinguish one element from another. For example, a first object or step may be referred to as a second object or step, and similarly, a second object or step may be referred to as a first object or step, without departing from the scope of this disclosure. The first object or step and the second object or step are both objects or steps, but they should not be regarded as the same object or step.

[0076] The terminology used in this description is for the purpose of describing particular embodiments and is not intended to be limiting. As used in this specification and the appended claims, the singular forms “a” and “an” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and covers any possible combination of one or more of the associated listed items. It should also be further understood that the terms “comprising,” “including,” “having,” and / or “containing,” when used in this specification, specify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. Furthermore, as used herein, the term “if” can be interpreted as meaning “when” or “in response to determination” or “in response to detection,” depending on the context.

[0077] The disclosed embodiments provide an engineered biochar suitable for alkaline desert soils. It should be understood that the description is not intended to limit the invention. Rather, the embodiments are intended to cover alternatives, modifications, and equivalents included within the spirit and scope of the invention as defined by the appended claims. Furthermore, numerous specific details are set forth in the detailed description of the embodiments to provide a full understanding of the claimed invention. However, those skilled in the art will understand that various embodiments can be practiced without these specific details.

[0078] Although the features and elements of this embodiment are described in specific combinations in the embodiment, each feature or element may be used alone without other features and elements of the embodiment, or with or without other features and elements in various combinations with other features and elements disclosed herein.

[0079] This written description uses examples of the disclosed subject matter to enable any person skilled in the art to practice the same, including making and using any apparatus or system and performing any incorporated methods. The patent scope of the claimed subject matter is defined by the claims and may include other examples that would occur to a person skilled in the art. These other examples are intended to fall within the scope of the claims.

Claims

1. An engineered biochar (150), comprising: Multiple particles (162), each particle (162) contains Hydrogen atom (152), Oxygen atom (153), Carbon atom (154), and Ash containing one or more nutrient atoms (156), The engineered biochar (150) described herein has the following characteristics: pH range of 1 to 8.5 Conductivity ranging from 0.01 dS / m to 4.95 dS / m, measured using a 1:10 ratio of engineered biochar to water. The soluble salt content is 0.01% to 3% of the total dry mass of the engineered biochar. The ash content is 10% to 50% of the total dry mass of the engineered biochar, and The molar ratio of hydrogen to organic carbon is 0.1 to 0.

7.

2. The engineered biochar according to claim 1, wherein the pH is about 7, the conductivity is about 1.5 dS / m, the soluble salt content is about 0.58%, the soluble salt is soluble in water, the ash content is about 45%, the hydrogen to organic carbon molar ratio is about 0.5, and the individual size of the plurality of particles is less than 10 mm.

3. The engineered biochar according to claim 1, wherein one or more nutrient atoms are at least one of the following: Potassium, comprising 0.7 to 2% of the total mass by weight, Calcium, comprising 5 to 10% of the total mass by weight, or Copper, which accounts for 0.001 to 0.2% of the total mass by weight.

4. The engineered biochar according to claim 1, wherein the soluble salt content is caused by soluble salts, wherein the soluble salts are water-soluble salts.

5. A biochar treatment unit (140) configured to remove soluble salts to produce engineered biochar (150), said biochar treatment unit (140) comprising: There are N stages (i), each having N reactors (Ri), where N is a positive integer. The N reactors (Ri) are connected in series and configured such that... The raw biochar (210) enters the first reactor of the N reactors and passes sequentially through the remaining reactors as a slurry (Si) to become the engineered biochar (150) upon exiting the Nth reactor of the N reactors. Fresh water (FW) flows into the Nth reactor and removes soluble salts (158) from each remaining reactor, leaving the first reactor as brine (SW). Each stage (i) includes: A conveyor (Ci) configured to remove the slurry (Si) from the reactor (Ri), and A solid-liquid separator (SLSi) is configured to receive the slurry (Si) from the conveyor (Ci), separate the treated biochar from the slurry (Si), and move the treated biochar to the next reactor (R(i+1)).

6. The biochar treatment unit according to claim 5, wherein the reactor (Ri) is one of a continuous stirred tank reactor (CSTRi), a plug flow reactor (PFRi), or a reactor with an intermediate configuration.

7. The biochar treatment unit according to claim 5, wherein the reactor (Ri) is configured as a continuous stirred tank reactor (CSTRi) and includes a mixer (Mi) configured to mix the slurry (Si) to prevent particle settling.

8. The biochar treatment unit according to claim 5, wherein the solid-liquid separator (SLSi) comprises a sieve and a screw, the sieve and the screw being simultaneously rotated by an electric motor to separate the slurry and advance the biochar to the next reactor. The solid-liquid separator (SLSi) is configured to discharge the separated biochar (MBi) to the next reactor (CSTR(i+1)) and return the reflux water (BFWi) to the current reactor (CSTRi).

9. The biochar treatment unit according to claim 5, wherein the reactor (Ri) includes a settling zone to separate biochar from the slurry.

10. The biochar processing unit of claim 5, wherein the conveyor (Ci) comprises a screw rotated by an electric motor for lifting the slurry to the solid-liquid separator (SLSi).

11. The biochar treatment unit according to claim 5, wherein each reactor further comprises: The Particle Settling and Recirculation (PSBi) module is configured to separate brine from the slurry (Si) in the current reactor and move it to the previous reactor (R(i-1)).

12. The biochar treatment unit according to claim 11, wherein the particle settling and recirculation (PSBi) module comprises: The inner portion, located inside the tank of the current reactor, includes a feed port having one or more parallel plates attached to the port for receiving the slurry and reducing turbulence, allowing particles in the slurry to settle back into the turbulent region; as well as The outer portion, located outside the tank, includes a box having an adjustable-length plate for adjusting the liquid level inside the tank.

13. The biochar treatment unit according to claim 5, wherein N is 1, 2, 3, 4 or 5.

14. The biochar treatment unit according to claim 5, further comprising: An acid dispensing module (ADMi) is configured to dispense a fixed amount of acid to one or more reactors or stages.

15. The biochar treatment unit according to claim 5, further comprising: An additional substance distribution module (AS) is configured to distribute a quantitative amount of chemicals, and / or micronutrients and / or microbial mixtures to one or more reactors or stages.

16. A method (300) for preparing engineered biochar (150), the method comprising: The original biochar (210) is fed (302) into the current reactor; Brine feed (304) is fed from the next reactor into the current reactor; Remove (308) washed biochar from the current reactor; as well as The washed biochar is separated from the brine (310) to obtain the engineered biochar (150). The engineered biochar (150) described herein has the following characteristics: pH range of 1 to 8.5 Conductivity ranging from 0.01 dS / m to 4.95 dS / m, measured using a 1:10 ratio of engineered biochar to water. The soluble salt content is 0.01% to 3% of the total dry mass of the engineered biochar. The ash content is 10% to 50% of the total dry mass of the engineered biochar, and The molar ratio of hydrogen to organic carbon is 0.1 to 0.

7.

17. The method of claim 16, wherein the reaction time is from 1 minute to 96 hours.

18. The method of claim 16, further comprising: The engineered biochar is then fed into the next reactor for further washing.

19. The method of claim 16, further comprising: In the next reactor or stage, acid is added to the engineered biochar to lower its pH.

20. The method of claim 16, further comprising: Additional substances are added to the reactor or stage, including chemicals and / or micronutrients and / or microbial mixtures.

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