Method for producing calcium carbonate materials or materials containing calcium carbonate

Abstract

The invention relates to the field of materials science and relates to a method for producing calcium carbonate materials or materials containing calcium carbonate, as can be used, for example, in the building industry as biogenic building and construction materials. The aim of the present invention is to provide a method in which calcium carbonate materials are produced in a sustainable manner and, in particular, CO2 is consumed, for example from the environment. The problem is solved using a method in which, in order to produce calcium carbonate in a microbiologically-induced manner, at least one calcium material or non-calcium material having pores is brought into contact with at least cyanobacteria in an environment containing carbon dioxide and water or water vapour, wherein, at least when only non-calcium material having at least the cyanobacteria is present, calcium material or material containing calcium is also introduced, and furthermore at least light is introduced in order to photosynthesise the cyanobacteria, and, after the calcium carbonate is produced in a microbiologically-induced manner, the produced calcium carbonate material is completed.

Description

[0001] Process for the production of calcium carbonate materials or calcium carbonate-containing materials

[0002] The invention relates to the fields of materials science and construction and concerns a process for the production of calcium carbonate materials or calcium carbonate-containing materials, such as those used in construction as biogenic building and construction materials in various shapes and structures, such as panels or parts of facades or for translucent concrete, for shaped blocks, for formwork elements or for biogenic bricks or masonry units, or for large structures, such as in the field of foundation structures for (offshore) wind turbines, e.g. for the foundation base for a jacket structure, for anchor points for floating offshore wind turbines or for foundation bases for gravity foundations.

[0003] The goal for the industrial sector is to halve carbon dioxide emissions by 2030. In 2017, industrial emissions amounted to 193 million tonnes of CO2, of which 20.5 million tonnes of CO2 were attributable to cement production and 121 million tonnes of CO2 to building construction.

[0004] Cement is an inorganic, non-metallic building material. Its production is made from the natural raw materials limestone and clay. The raw materials are ground into a raw meal and then heated to approximately 1,450 °C to produce cement clinker. During firing, the carbon dioxide bound in the lime is released (Wikipedia, keyword "cement").

[0005] As economic growth increases, more and more large-scale buildings, high-rise buildings, and / or underground facilities are being constructed. As a result, global cement consumption is forecast to rise significantly by 2050 due to population growth, urbanization, and increasing infrastructure development.

[0006] However, these good economic prospects pose a problem for the climate, as cement production causes high greenhouse gas emissions.

[0007] However, the raw materials required for the production of various common cements and concretes, such as sand and gravel, are becoming increasingly scarce or are associated with increasingly high costs.

[0008] Therefore, there is a need for intelligent designs and economically viable replacement solutions, and replacement with renewable raw materials, alternative cements (low carbon cement), recycled concrete, energy-efficient carbon capture and storage, and above all, carbon capture and utilization approaches is becoming increasingly important.

[0009] But also given the rapid urbanization worldwide, most large buildings are being built close to one another, so that natural sunlight on and within the buildings is severely reduced. This, and also in connection with the pursuit of "well-being and health," requires solutions that, on the one hand, meet the growing environmental awareness for alternative "green" cements and concretes and building materials, and, on the other hand, enable the sense of well-being provided by natural light and / or the need for light to promote / maintain biological metabolic activities in living organisms.

[0010] To provide more light and also for more architectural / artistic purposes, "light-transmitting concrete" (Litracon) was first developed in 2001 by Hungarian architect Aron Losonczi (EP 2 179 105 A2). The world's first commercially available transparent concrete, Litracon Classic®, is a combination of optical fibers and fine-grained concrete. It can be manufactured as prefabricated building blocks by pouring them layer by layer into prefabricated molds. Due to the small size of the fibers, they are integrated into the concrete in a barely visible manner.

[0011] Two materials—glass and concrete—are blended to create a composite material that is homogeneous both in its internal structure and on its main surfaces. Litracon Classic® is a completely handcrafted product, creating a unique light pattern in each piece (www.litracon.hu).

[0012] Since the proportion of glass fibers in Litracon is low at 4% and they also have a small diameter of 2 micrometers to 2 millimeters, the stability corresponds to that of ordinary concrete.

[0013] The more optical fibers inserted and the more densely they are packed, the more transparent the material. The almost loss-free light transmission through the optical fibers makes it possible to see light, shadows or even colors even with greater wall thicknesses. Unlike Litracon Classic®, Litracon pXL® does not use optical fibers to transmit light, but rather a specially shaped plastic unit. The manufactured panels are reinforced with this plastic unit and can be storey high. The light points appear evenly distributed on the surface of the pXL® panels, like pixels on an LCD screen. Litracon pXL® technology can also be used to create not only simple panels, but also 3D objects such as folded or curved shapes and hollow bodies.

[0014] These materials can therefore be used in a wide range of architectural and interior design applications, including cladding and partition walls.

[0015] However, the use of renewable building materials and recycling processes is crucial for ecological sustainability. In conventional concrete, however, the influence on chemical reactivity is exhausted with the hydration and hardening of the cement. Concrete recycling technology is therefore limited to the use of waste concrete as an aggregate (Tam, VWJ Clean. Prod. 17 (2009), 688-702; Kou, SC, et al: Cement Concrete Compos. 32 (2010), 649-654). As an alternative production route to novel concretes and alternative cements—including the cements and concretes used for Litracon—biologically inspired routes are increasingly being considered, such as the production of so-called Living Building Materials (LBM) using microorganism-polymer composites to produce building materials.

[0016] Initial approaches were developed to produce building materials from urine, sand, and bacteria: human urine mixed with CaOH2 stabilized urease. This enzyme was then used to initiate calcification with bacteria of the species Sporosarcina pasteurii, forming calcium carbonate and hardening the mass. However, the resulting bioconcretes exhibited strengths of only 2.7 MPa (Lambert, SE, et al; Water Research 160(1) (2019), 158–166).

[0017] In the work of Pilehvar et al.: J. of Cleaner Production 247 (2020) 119177, a synthetic powdered lunar rock, a regolith simulant, was used in conjunction with urease-based calcification to produce a solid structural body. Material extrusion allowed the construction of smaller strands, some of them layered. The strengths reached 32 MPa. The rationale for this, especially for space-specific approaches, is the use of local resources (rock from the moon, human urine) to produce materials.

[0018] Research by A.D. Roberts et al. (Materials Today Bio, Volume 12, (2021), 100136) goes a step further. They used Lunar Highlands Simulant 1 (LHS-1) and Martian Global Simulant 1 (MGS-1) to solidify extraterrestrial regolith biocomposites (ERBs) using human serum albumin as a binder and urine. Strengths of up to 37.9 MPa were achieved. Here, too, simple material extrusion led to rudimentary layered structures.

[0019] When bacterial cells are added to gelatin hydrogels, they can be enhanced by microbially induced calcium carbonate precipitation (MICP). This technology is used, among other things, to improve soils (Ivanov, V., et al: (2008) Rev. Environ. Sei. Biol. Technol. 7, 139-153; Van Paassen, LA, et al:(2010) Ecol. Eng. 36, 168-175; Chu, J., et al: (2012) Geomicrobiol. J. 29, 544-549) and concrete have been used (De Muynck, W., et al: (2010) Ecol. Eng. 36, 118-136; Ghosh, S., et al: (2009) Cement Concrete Compos. 31 , 93-98; Jeong, JH et al: (2017). J. Microbiol. Biotechnol. 27, 1331-1335). If the gelatin gels dry out, they can be redissolved in water at slightly elevated temperature, the solution recycled with bacteria, and reused to produce new LBMs (Qiu et al: iScience 24, 102083, February 19, 2021 ).

[0020] Governments around the world spend billions of dollars annually to repair cracks in concrete structures and maintain infrastructure. To counteract this, Green Basilisk (www.basiliskcon-crete.com) combines concrete with bacterial spores and calcium lactate. The spores can remain in the concrete matrix for years before being "awakened" by water ingress (after cracking) and transforming into active bacteria. These bacteria then begin digesting the lactate and producing CO2. The concrete thus heals itself, as the calcium ions released from the calcium lactate combine with the CO2 to form calcium carbonate due to the high pH value in the concrete.

[0021] Microorganism-polymer-mineral-based construction materials are most readily available from the biotech company bioMASON INC (biomason.com), which uses a urea-producing wild-type Bacillus strain capable of bonding rock and sand grains together to form stable tile-like structures. The bacteria hydrolyze urea as a starting material to CO2, which combines with calcium ions to form calcium carbonate. This carbonate binds the surrounding rock grains into a solid matrix within a tile shape. After three days, these bioLITH® tiles are as dimensionally stable as wet sandcastles and only need to dry at room temperature before they can be used for walls or floors (Jeong, JH, et al: (2017) J. Microbiol. Biotechnol. 27, 1331-1335). Here, CO2 is generated in situ, but calcium carbonate must first be thermally decomposed. CO2 is not removed from the atmosphere. Furthermore, the use of particulate raw materials is unavoidable.

[0022] US 2012137931 A1 uses bacteria that allow biosilicification, i.e., the biologically triggered formation of SiO2. This allows the production of special concrete compositions and cements containing biomolecules with silica-releasing activity (including proteins) using cementitious materials, such as sand and gravel (or a combination thereof). Furthermore, the production of brick-like building materials from mixtures of gelatin, sand, and the cyanobacterium Synechoccocus sp. PC 7002 is known. This cyanobacterium causes the composite matrix to solidify over time through calcium carbonate mineralization (Qiu et al.: iScience 24, 102083, February 19, 2021; Heveran, CM et al., Matter 2020, 2, 481-494). This novel LBM even allows for complete material recycling.However, the organic hydrogels used there are too soft without additives for use as load-bearing materials and are therefore only suitable for applications such as tissue engineering. The maximum compressive strength was approximately 4 MPa.

[0023] The “biologically induced carbonate precipitation” (MICP; microbially-induced carbonate precipitation) that also occurs there is known as a possibility for in-situ CaCOs mineral production by means of microorganisms (see comparison above).

[0024] For example, approximately 20-30% of global photosynthetic carbon dioxide fixation is carried out by cyanobacteria. Photosynthesis occurs through two reactions: the light reaction and the dark reaction.

[0025] The light reaction is a complex electron transport chain that involves the formation of energy-rich molecules (in the form of ATP and NADPH), the oxidation of water, and the release of oxygen. This leads to the consumption of H + and thus contributes to alkalization. This alkalization is the driving force for calcium carbonate formation by Cyanoprokaryota bacteria. Cyanobacteria are blue-green algae, oxygen-photosynthetic bacteria (prokaryotes), which are currently taxonomically called "Cyanoprokaryota" (Minerals, 2012, 2, 338-364).

[0026] The dark reaction, known as the Calvin cycle, is a complex biochemical process in which carbon dioxide is fixed in the form of sugar using energy-rich molecules from photosynthesis. The Calvin cycle is based on the CO2-binding enzyme RuBisCO (ribulose-1,5-bisphosphate carboxylaseZ-oxygenase), which is a key enzyme for CO2 fixation. The enzyme transfers a CO2 molecule to ribulose-1,5-bisphosphate, producing two molecules of 3-phosphoglycerate. In cyanobacteria, the synthesis takes place in the carboxysome. The reaction relies on CO2 as a substrate. Carbon concentration mechanisms (CCM), a system for enriching the internal CO2 pool, can compensate for enzyme undersaturation. Calcium carbonate is then formed when the carbon in the cytosol is absorbed into the cell in the form of CO2 via diffusion and enzymatically converted into HCOs.The HCO2 is then transported to the carboxysome and converted into CO2 by carbonic anhydrase to serve as a substrate for RuBisCo. During the enzymatic conversion to CO2, H2 is consumed. + and a release of OH' (dark reaction). In addition, there is a consumption of H + (Light reaction). This leads to alkalization of the cell exterior and significantly influences calcium carbonate formation outside the cell membrane. As a result of alkalization, dissolved CO2 is present mainly as CO2. 2 ' and leads to the precipitation of calcium carbonate through the accumulation of calcium. The calcium is present in dissolved ionic form Ca 2+, such as in water. Other important factors for calcium carbonate formation are cellular surface structures, so-called S-layer proteins, and exopolysaccharides (EPS), which act as crystallization nuclei. Thus, cyanobacteria are of great ecological importance in the global carbon and nitrogen cycle.

[0027] Furthermore, from DE 102010 039322 A1 a method and a device for the continuous production of foams are known, in which foaming material is continuously introduced through a hollow body in which a static mixer is located, and gas / gas mixtures or liquid / liquid mixtures are pressed through the porous hollow body wall by setting the gas or liquid pressure in the free volume higher than the pressure in the cavity of the hollow body and the counterpressure of the porous hollow body wall, then the foamed material is continuously removed from the hollow body and converted into a solid foam state.

[0028] Disadvantages of the state-of-the-art solutions are mostly the immature technologies for the production of "green" calcium carbonate-containing materials or calcium products that are produced from calcium carbonate-containing starting materials, even in sufficient quantities, and in the production of calcium carbonate-containing materials using the long-known methods, the lack of sustainability of the production and the high CO2 emissions during the production of such materials.

[0029] The object of the present invention is to provide a process for the production of calcium carbonate materials or calcium carbonate-containing materials, in which a sustainable production of calcium carbonate materials or calcium carbonate-containing materials is realized and in particular not only the CO2 emissions are reduced, but also CO2 is consumed, for example from the environment.

[0030] The object is achieved by the invention defined in the claims. Advantageous embodiments are the subject of the dependent claims, whereby the invention also includes combinations of the individual dependent claims in the sense of an AND connection, as long as they are not mutually exclusive.

[0031] In the process according to the invention for producing calcium carbonate materials or calcium carbonate-containing materials, at least

[0032] - a calcium-containing or calcium material with pores or a calcium-containing or calcium material into which pores have been introduced and / or which are adjusted with regard to pore size, and / or

[0033] - a non-calcium-containing or non-calcium material with pores or into which pores have been introduced and / or the pore size is adjusted, or a lumpy or powdery non-calcium-containing material, is brought into contact with at least cyanobacteria in an environment containing carbon dioxide and water or water vapor, wherein at least in the case of the presence of only non-calcium-containing or non-calcium material with at least the cyanobacteria, calcium-containing or calcium material is also introduced, and furthermore at least light is introduced to at least the cyanobacteria to realize the photosynthesis of the cyanobacteria, and after the microbiologically induced calcium carbonate production, the produced calcium carbonate material or the produced calcium carbonate-containing material is finished or can be further processed.

[0034] Advantageously, natural calcium powder, calcium silicate powder, sand, recycled building materials, construction rubble, mineral rocks, silicates, gravel, crushed stone, granite, basalt, clay, ceramic powder, polyurethane are used as calcium-containing or calcium material and / or as non-calcium-containing or non-calcium material, and wherein in the case of the introduction of non-calcium-containing or non-calcium material as starting materials, a calcium-containing or calcium material is introduced with the cyanobacteria, wherein even more advantageously the nutrient solution of the cyanobacteria is used as the liquid in which the cyanobacteria are located, which in the case of the introduction of calcium-containing or calcium material with the cyanobacteria also contains calcium-containing or calcium material.

[0035] Furthermore, the introduction of pores or the adjustment of pore sizes in a calcium-containing or calcium material is advantageously carried out by the introduction of gases, such as carbon dioxide or carbon dioxide-containing gases, into the calcium-containing or calcium material or by applying calcium-containing or calcium materials to foams or by introducing spacers that are removed, or by freeze-foaming, wherein the introduction of gases into the calcium-containing or calcium material is even more advantageously carried out by chemically or physically induced or by pressure foaming, by stirring or by gas introduction, for example by compressed air, and / or even more advantageously calcium-containing or calcium materials are applied to foams made of polymers or ceramic materials and solidified on their surface, wherein the foam materials can subsequently be removed,and / or more advantageously, a suspension is prepared from the calcium-containing or calcium material and / or from the non-calcium-containing or non-calcium material with a suspension medium, and this suspension is subjected to a vacuum and / or a temperature reduction, and the suspension medium is sublimated. Also advantageously, a pore size of the calcium-containing or calcium material or the non-calcium-containing or non-calcium material of 0.3 to 10,000 μm, more advantageously of 10 to 5,000 μm, even more advantageously of 100 to 1,000 μm, is present or is introduced or adjusted.

[0036] And also advantageously, predominantly open pores, advantageously only open pores if possible, are created in the calcium-containing or calcium material or in the non-calcium-containing or non-calcium material and / or their pore size is adjusted.

[0037] It is also advantageous if ambient air or industrially produced gases, such as CO2 produced in industrial processes, which may have been purified and concentrated, are used as the environment containing carbon dioxide and water or water vapor.

[0038] It is also advantageous if a strain of Cyanoprokarvota is used as cyanobacteria, whereby the cyanobacteria can also be used in combination with urease-producing and urea-decomposing bacteria, such as Helicobacter pylori, Klebsiella, Proteus, Staphylococcus saprophyticus, Yersinia or species of Enterobacter and Citrobacter.

[0039] It is also advantageous if cyanobacteria are used together with a nutrient solution for these cyanobacteria, whereby at least in the case of the presence of only non-calcium-containing or non-calcium material, calcium-containing or calcium material is also introduced with the cyanobacteria via the nutrient solution.

[0040] It is also advantageous if cyanobacteria are brought together with at least one calcium-containing or calcium material and / or with at least one non-calcium-containing or non-calcium material or with a lumpy or powdery non-calcium-containing material, and with a material for immobilizing the cyanobacteria, wherein gels, gelatin, hydrogels, crosslinking and / or polymerizing and / or hardening sols and / or additives are advantageously used as materials for immobilizing the cyanobacteria.

[0041] It is also advantageous if light with a wavelength of 380 nanometers (nm) to 780 nm is introduced to the cyanobacteria to realize photosynthesis, whereby several wavelengths can also be used together, such as 660 nm and 730 nm.

[0042] It is furthermore advantageous if sunlight and / or artificial light and / or light which is realized via at least one light-conducting and light-emitting material or component is introduced as light for realizing the photosynthesis of the cyanobacteria, wherein light guides, optical fibers, LEDs, OLEDs, diodes, glass components are advantageously introduced as light-conducting and light-emitting materials or components.

[0043] It is also advantageous if light-conducting and light-emitting materials or components are introduced before, simultaneously or immediately after the introduction of pores and / or with the adjustment of a pore size in a calcium-containing or calcium material.

[0044] It is also advantageous if light-conducting and light-emitting materials or components are introduced before, at the same time as, or immediately after the introduction of immobilizing materials for the cyanobacteria.

[0045] It is also advantageous if, after the microbiologically induced calcium carbonate production, the calcium carbonate-containing material produced is finished as a building material or is further processed as a semi-finished product or reused as a building material.

[0046] The present invention makes it possible for the first time to provide a process for producing calcium carbonate materials or calcium carbonate-containing materials in which a sustainable production of calcium carbonate materials or calcium carbonate-containing materials is realized and in particular not only reduces CO2 emissions but also consumes CO2, for example from the environment.

[0047] This is achieved by a process for the production of calcium carbonate materials or calcium carbonate-containing materials in which calcium carbonate production / calcium carbonate precipitation (MICP) is realized via microbiologically induced processes.

[0048] The particular advantage of the inventive solution is that the production of calcium carbonate materials or calcium carbonate-containing materials is sustainable, and after completion of the desired product, living cyanobacteria can still be present, which can continue to convert to calcium carbonate. This can lead to a "living" material that not only continues to consume CO2 from the air but also releases oxygen.

[0049] For the realization of calcium carbonate production according to the invention, at least

[0050] - a calcium-containing or calcium material with pores or a calcium-containing or calcium material into which pores have been introduced and / or adjusted with regard to pore size, and / or

[0051] - a non-calcium-containing or non-calcium material with pores or into which pores have been introduced and / or are adjusted with regard to pore size, or a lumpy or powdery non-calcium-containing material, brought into contact with at least cyanobacteria in an environment containing carbon dioxide and water or water vapor.

[0052] Natural calcium powders, calcium silicate powders, sand, recycled building materials, construction rubble, mineral rocks, silicates, gravel, crushed stone, granite, basalt, clay, ceramic powders, and polyurethanes are advantageously used as calcium-containing or calcium-containing materials and / or as non-calcium-containing or non-calcium materials. If non-calcium-containing or non-calcium materials are used as starting materials, a calcium-containing or calcium-containing material must be introduced with the cyanobacteria, for example, as a component of the liquid in which the cyanobacteria are located.

[0053] The nutrient solution of the cyanobacteria can be used as the liquid in which the cyanobacteria are located, which, in the case of the introduction of calcium-containing or calcium material with the cyanobacteria, also contains calcium-containing or calcium material.

[0054] The calcium-containing or calcium-based material used according to the invention may also contain a small amount of natural limestone, which can act as a kind of "inoculation material." However, the solution according to the invention is essentially intended to replace natural limestone as a material, thus conserving resources.

[0055] According to the invention, calcium powder can be used, for example, as CaSC, CaHPC or CaCl2 or other Ca salts or Ca brine, or it can be obtained from Ca-containing rocks and Ca-containing mineral rocks, such as basalt or from sea water.

[0056] As already mentioned, the respective calcium powder may already contain portions of CaCOs, which can serve as “inoculation germs”.

[0057] Other sources of calcium-containing materials can also be aggregates such as construction rubble, recycled construction rubble, sands, gravels, granites, clays, ceramic powders or mineral powders, to which calcium can also be added.

[0058] Likewise, "matrix materials" that contain calcium in any form or phase, or to which additional calcium is added, such as polyurethane or silicon dioxide sols, colloidal silicon dioxide, (hydro)gels or gelatin, agar, and sodium alginates, can be used as calcium-containing materials according to the invention. Porosity can already be created during the production of these materials. Of course, mixtures of all of the aforementioned calcium-containing materials can also be used according to the invention.

[0059] However, other materials that do not contain calcium themselves but are required for the desired product, such as MgSC or magnesium salts, can also be used.

[0060] The calcium-containing material can be a material that already has pores, or another porous material can be used together with a calcium-containing material.

[0061] It is an advantage according to the invention that the solution according to the invention can introduce a desired quantity and size of pores into a material, in particular into a calcium-containing or calcium material which has no or insufficient pores.

[0062] Advantageously, a pore size of the pores of the calcium-containing or calcium material or the non-calcium-containing or non-calcium material of 0.3 to 10,000 pm, advantageously of 10 to 5,000 pm, even more advantageously of 100 to 1,000 pm, should be present or introduced or adjusted.

[0063] In the case of the introduction of materials which, upon completion, will yield concrete, a porosity factor P is specified for such building materials, which is defined as the product of the specific permeability coefficient K and the maximum M of the differential pore distribution, e.g., or the permeability coefficient alone.

[0064] Concrete is known to have various pores with varying pore sizes, such as compaction pores, air pores, capillary pores, or gel pores. While the pore size of compaction and air pores is in a size that can still be perceived either with the naked eye or at least with a light microscope (determination of air void parameters in hardened concrete in ÖNORM B3303 Concrete Testing) and in the size range from 10 pm to 10,000 pm, the pore sizes of the so-called gel and capillary pores are in the size range from 0.001 to 10 pm. According to the invention, all such pores can be present and / or introduced across the entire aforementioned pore size range. The realization of a carbon dioxide and water or water vapor-containing environment is possible in such pores, as is bringing them into contact with cyanobacteria.

[0065] However, the pore size for contacting and calcium carbonate production / calcium carbonate precipitation (MICP) via microbiologically induced processes is limited by the size of the cyanobacteria that are to enter the pores, otherwise calcium carbonate production cannot occur in the pores. The diameter or largest dimension of cyanobacterial cells generally varies between 0.3 and 1 pm to 60 pm.

[0066] The pores in a calcium-containing or calcium material and / or in a non-calcium-containing or non-calcium material can advantageously be introduced and / or their pore size adjusted, for example by introducing gases into the calcium-containing or calcium material and / or into the non-calcium-containing or non-calcium material, or by applying such materials to or into foams. The calcium-containing or calcium materials and / or the non-calcium-containing or non-calcium materials are advantageously in a suspension or solution.

[0067] In the case of the introduction of gases into the calcium-containing or calcium material and / or into the non-calcium-containing or non-calcium material, this can also be achieved by chemically or physically induced or by pressure foaming, by stirring or by gas introduction, for example by compressed air.

[0068] A process for the continuous production of foams is known in which material to be foamed is continuously introduced through at least one inlet into a hollow body in which a static mixer is located.The material to be foamed is continuously transported through the hollow body, wherein gas / gas mixtures or liquid / liquid mixtures are pressed through the hollow body wall through at least regions of the hollow body wall which are porous, and the material to be foamed is processed by means of the static mixer with the gas to form foam or with the liquid to form a dispersion, wherein when a liquid is used the distributed liquid droplets are only removed outside the device by drying or selective dissolving from the dispersion and thus a foam is formed, and the foamed or dispersed material is continuously transported out of the hollow body through at least one outlet, and the foamed or dispersed material is converted into a solid foam state (DE 10 2010 039 322 A1).

[0069] The pores can also advantageously be introduced into calcium-containing or calcium material and / or into non-calcium-containing or non-calcium material. The introduction of pores into these materials can be achieved, for example, using the Schwartzwalder, spacer, or direct foaming process. Calcium-containing or calcium materials and / or non-calcium-containing or non-calcium materials can also be applied to foams made of polymers or ceramic materials that have been solidified using the Schwartzwalder, spacer, direct foaming, or freeze-foaming process.

[0070] In freeze-foaming, calcium-containing or calcium material and / or non-calcium-containing or non-calcium material are combined with a suspending agent to form a suspension and subjected to a vacuum and / or a temperature reduction to solidify / freeze the suspension. Subsequently, the suspending agent is sublimated and removed, and the solidified porous calcium-containing or calcium material and / or the non-calcium-containing or non-calcium material can then be further processed, for example, heat-treated.

[0071] The porous calcium-containing or calcium material and / or a non-calcium-containing or non-calcium material is then brought into contact with cyanobacteria in a carbon dioxide and water or water vapor-containing environment. Furthermore, it is according to the invention that in the calcium-containing or calcium-

[0072] material and / or non-calcium-containing or non-calcium material predominantly open pores, advantageously only open pores, are created and / or their pore size is adjusted so that the cyanobacteria can advantageously enter the entire or the desired volume of this

[0073] Materials penetration and the calcium carbonate production /

[0074] Calcium carbonate precipitation (MICP) can be achieved via microbiologically induced processes. In existing closed pores, the

[0075] Calcium carbonate production cannot be realized.

[0076] Advantageously, ambient air or industrially produced gases, such as CO2 produced in industrial processes, which may have been purified and concentrated, are used as the environment containing carbon dioxide and water or water vapor.

[0077] The amount of carbon dioxide and water or water vapor is determined by the number of cyanobacteria and their photosynthetic activity. If there is too little carbon dioxide and water or water vapor in the cyanobacterial area, calcium carbonate production / calcium carbonate precipitation (MICP) via microbiologically induced processes will not occur. Likewise, calcium carbonate production / calcium carbonate precipitation (MICP) via microbiologically induced processes will not occur if there is too little light at the respective location.

[0078] For the purposes of the present invention, cyanobacteria are understood to mean bacteria that belong to the cyanoprokaryota, such as cyanophytes, Synechocystis sp. PCC 6803, Synechococcus sp. PCC 7002, Synechococcus elongatus PCC 7942, 11801, 11802, 11901, UTEX 2973.

[0079] The cyanobacteria used can be used together with a nutrient solution for these cyanobacteria, whereby at least in the case of the presence of only non-calcium-containing or non-calcium material with the cyanobacteria via the liquids in which the cyanobacteria are located, the nutrient solution of the cyanobacteria, also calcium-containing or calcium material, must advantageously be introduced.Furthermore, the cyanobacteria can advantageously be brought together with at least one calcium-containing or calcium material and / or with at least one non-calcium-containing or non-calcium material or with a lumpy or powdery non-calcium-containing material, and with a material for immobilizing the cyanobacteria, wherein gels, gelatin, hydrogels, crosslinking and / or polymerizing and / or hardening sols and / or additives are used as materials for immobilizing the cyanobacteria.

[0080] A combination of cyanobacteria with urease-forming and urea-decomposing bacteria, such as Helicobacter pylori, Klebsiella, Proteus, Staphylococcus saprophyticus, Yersinia or species of Enterobacter and Citrobacter, can also be used according to the invention.

[0081] According to the invention, it is further necessary that light is introduced at least to the cyanobacteria in order to realize the photosynthesis of the cyanobacteria.

[0082] Only when living cyanobacteria are brought into contact with calcium in any form, phase or compound in a carbon dioxide and water or water vapor-containing environment and in contact with light can the microbiologically induced calcium carbonate production take place.

[0083] Only with the help of light can the photosynthesis of cyanobacteria take place.

[0084] The light to be introduced advantageously has a wavelength of 380 nanometers (nm) to 780 nm, although several wavelengths can also be used together, such as 660 nm and 730 nm, which are necessary and advantageous for the realization of the photosynthesis of the cyanobacteria.

[0085] The light used to facilitate photosynthesis by the cyanobacteria can advantageously be sunlight and / or artificial light and / or light that reaches the cyanobacteria via at least one light-conducting and light-emitting material or component. Light guides, optical fibers, LEDs, OLEDs, diodes, and glass components can advantageously be used as light-conducting and light-emitting materials or components.

[0086] These light-emitting materials can be used in the form of plates, mats or fiber strands, individual LEDs or OLEDs or diodes or arrays thereof.

[0087] How and which light is introduced to the cyanobacteria depends on the specific cyanobacterium, whether the sunlight and / or artificial light can reach all cyanobacteria and the pores in the material.

[0088] Typically, sunlight and artificial light only reach the cyanobacteria present on the surface or in the open areas close to the surface.

[0089] In order to achieve microbiologically induced calcium carbonate production within the materials, advantageously throughout the entire volume of the material, the cyanobacteria must be able to reach the material, which can be achieved by pouring or immersing the materials in liquids containing cyanobacteria, by infiltration processes, or even by mixing entire materials with cyanobacteria. On the other hand, light must also be able to reach the material, which, at least in such a case, but also independently, can be achieved according to the invention by a light-conducting and light-emitting material or component that has been introduced into and / or onto the porosity of the calcium-containing material.

[0090] The light-conducting and light-emitting materials or components can be introduced beforehand, simultaneously or immediately subsequently with the introduction of pores and / or with the adjustment of their pore size in a calcium-containing or calcium material and / or in a non-calcium-containing or non-calcium material.

[0091] It is also advantageous according to the invention if the light-conducting and light-emitting materials or components are introduced before, simultaneously with, or immediately after the introduction of immobilizing materials for the cyanobacteria. If the light-conducting and light-emitting materials or components are to be introduced into the interior or volume of the materials, the introduction must be carried out before the hardening or solidification of the calcium-containing or calcium materials and / or the non-calcium-containing or non-calcium materials.

[0092] These light-conducting and light-emitting materials or components can, after the realization of the microbiologically induced calcium carbonate production and the associated conversion of calcium into calcium carbonate, also be used as light sources for wavelengths other than those required for the realization of cyanobacterial photosynthesis.

[0093] To accelerate the conversion of calcium into calcium carbonate, heat treatment can be carried out to improve the conditions for photosynthesis of the cyanobacteria used.

[0094] Likewise, for faster hardening or solidification, the calcium-containing or calcium material and / or the non-calcium-containing or non-calcium material or the material for immobilizing the cyanobacteria can be subjected to a heat treatment.

[0095] After the microbiologically induced calcium carbonate production, a calcium carbonate material produced according to the invention or a calcium carbonate-containing material is obtained, which can advantageously be further processed as a building material or used as a building material.

[0096] According to the invention, the process of microbiologically induced calcium carbonate production does not need to be completely completed if the calcium carbonate materials or calcium carbonate-containing materials thus produced are further processed or reused.

[0097] As long as living cyanobacteria and calcium, carbon dioxide, moisture / water / nutrient solution, and light for photosynthesis are still present, conversion to calcium carbonate can and will continue. This can lead to a "living" building material. Microbiologically induced calcium carbonate production leads to biomineralization of the calcium-containing material, which can then also be used as a building material, such as translucent concrete.

[0098] This is especially true because the known material based on photoactive cyanobacteria and MICP could only be produced in small sample sizes due to a lack of sufficient pores. The lack of a sufficient number and size of pores limits the access of light, water, water vapor, and CO2, causing the cyanobacteria inside to die, and microbiologically induced calcium carbonate production in larger volumes of the material is no longer possible.

[0099] This can be significantly improved by the method according to the invention.

[0100] The calcium carbonate materials or calcium carbonate-containing materials produced according to the invention can also be used as starting materials for cement and concrete production or for other building materials.

[0101] The invention is explained in more detail below using several exemplary embodiments.

[0102] Example 1

[0103] A ceramic suspension is pumped at 700 ml / min through a hollow steel cylinder with a porous outer wall and a static mixer. The suspension consists of 64 wt.% basalt powder (Kremer Pigmente GmbH & Co. KG), 30 wt.% deionized water, 4 wt.% 2-molar sodium hydroxide solution, 1 wt.% surfactant W53 (Zschimmer & Schwarz GmbH & Co. KG), and 1 wt.% plasticizer Zusoplast PS1 (Zschimmer & Schwarz GmbH & Co. KG). Carbon dioxide is fed into the interior of the hollow steel cylinder at a pressure of 0.3 MPa and a flow rate of 700 ml / min. A peristaltic pump pumps the ceramic suspension through the interior of the porous hollow cylinder. The static mixer located there mixes the flowing ceramic suspension with the carbon dioxide bubbles flowing through the porous outer wall of the hollow cylinder to form a foam. The foam leaves the device through the 10mm concentric opening on the outlet face.Based on the total volume flow through the device, 50% by volume of carbon dioxide is introduced into the foam through the porous wall of the hollow cylinder. The emerging foam is placed into a wooden formwork for a wall measuring 15,000 cm. 3 (L x W x H, 50 cm x 50 cm x 6 cm), cast.

[0104] Before the foam was applied, SiC glass fiber mats were inserted into the formwork, and these are surrounded by the foam. Light is guided into the interior of the wall through the glass fiber panels.

[0105] The foam then cures with the SiC glass fiber mats inside the wall to be created by the formwork, monitored by ultrasonic measurement technology. The introduced CC bubbles make the wall porous. During curing, destabilizing effects such as drainage, coalescence, and / or Ostwald ripening should be avoided or minimized as much as possible.

[0106] The cured foam in the formwork is repeatedly mixed with 2000 ml of a conventional nutrient medium A + Medium (Algal Culture Medium, UTEX) with an amount of OD730 = 0.3 of cyanobacteria of the strain Synechococcus PCC 7002 was watered and soaked.

[0107] Subsequently, at an ambient temperature of approximately 35°C, light with a wavelength in the range of 400-500 nm is directed through the SiO2 glass fiber mats into the interior of the wall in the formwork and thus into the interior of the porous foam for 8 hours, triggering and implementing photosynthesis by the bacteria. The CO2 present in the bubbles can reach the organisms through dissolution processes in the nutrient medium from the porous foam and is converted into calcium carbonate by the bacteria, along with the calcium and water of the nutrient solution and the light. This microbiologically induced conversion of the bacteria into calcium carbonate gradually fills the porosity with biogenic CaCO3. For further conversion into calcium carbonate and / or to eliminate the porosity, the foam structure can be covered again with nutrient medium containing the cyanobacteria and saturated until a permanent supernatant forms.

[0108] After curing, the wall is demoulded and can be monitored using ultrasonic measuring technology for service life, damage, etc.

[0109] The process of converting calcium into calcium carbonate can continue even after demoulding.

[0110] Example 2

[0111] A suspension is pumped at 700 ml / min through a hollow steel cylinder with a porous outer wall and a static mixer. The suspension consists of 20 mass% A + Nutrient medium (UTEX Culture Collection of Algae), with an amount of OD730 = 0.3 of cyanobacteria of the strain Synechococcus PCC 7002 (The Pasteur Culture Collection) of Cyanobacteria, 69 wt.% basalt powder (Kremer Pigmente GmbH & Co. KG), 10 wt.% deionized water and 1 wt.% surfactant W53 (Zschimmer & Schwarz GmbH & Co KG).

[0112] Carbon dioxide is introduced into the interior of the steel hollow cylinder at a pressure of 0.3 MPa and a volume flow of 700 ml / min. A peristaltic pump pumps the suspension through the interior of the porous hollow cylinder. The static mixer located there mixes the flowing ceramic suspension with the carbon dioxide bubbles flowing through the porous outer wall of the hollow cylinder to form a foam. The foam exits the device through the 10 mm concentric opening on the outlet face. Relative to the total volume flow conveyed through the device, 50 volume % of carbon dioxide is introduced into the foam through the porous wall of the hollow cylinder. The exiting foam is placed in a wooden formwork for a wall measuring 15,000 cm³. 3(L x W x H, 50 cm x 50 cm x 6 cm). After the foam was applied, SiO2 fiberglass mats were inserted into the formwork, which is then surrounded by the foam. Light is guided into the interior of the wall through the fiberglass panels.

[0113] The foam then cures with the SiC glass fiber mats inside the wall to be created by the formwork, monitored by ultrasonic measurement technology. The introduced CC bubbles make the wall porous. During curing, destabilizing effects such as drainage, coalescence, and / or Ostwald ripening should be avoided or minimized as much as possible.

[0114] Subsequently, at an ambient temperature of approximately 35°C, light with a wavelength in the range of 400-500 nm is directed through the SiO2 glass fiber mats into the interior of the wall in the formwork and thus into the interior of the porous foam for 10 hours, triggering and enhancing photosynthesis by the bacteria. The CO2 present in the bubbles can reach the organisms through dissolution processes in the nutrient medium from the porous foam and is converted into calcium carbonate by the bacteria through the calcium and water of the nutrient solution and the light. This gradually fills the porosity with biogenic CaCO3.

[0115] For further conversion into calcium carbonate and / or to eliminate porosity, the foam structure can be again poured over with nutrient medium containing the cyanobacteria and soaked until a permanent supernatant forms.

[0116] After curing, the wall is demoulded and can be monitored using ultrasonic measuring technology for service life, damage, etc.

[0117] The process of converting calcium into calcium carbonate can continue even after demoulding. Example 3

[0118] A suspension is poured into a geometric mold (L x W x H, 30 cm x 30 cm x 10 cm). The suspension consists of 20 mass% A + Nutrient medium containing cyanobacteria of the strain Synechococcus PCC 7002 (The Pasteur Culture Collection of Cyanobacteria) with an OD730 = 0.3, 69 wt% calcium silica powder, 10 wt% deionized water and 1 wt% surfactant W53 (Zschimmer & Schwarz GmbH & Co KG).

[0119] OLED arrays were inserted into the mold before the suspension was introduced, and they were surrounded by the suspension after the suspension was introduced. The OLEDs direct light into the interior of the mold and into the suspension.

[0120] The suspension containing the OLEDs is then cured inside the mold, monitored by ultrasonic measurement technology. The diffusion of CO2 from the ambient air or the introduction of gaseous CO2 leads to the formation of calcium carbonate through MICP.

[0121] After curing, the mold is demolded.

[0122] The process of converting calcium into calcium carbonate can continue even after demoulding.

[0123] Example 4

[0124] Synechococcus PCC 11801 (OD730 = 0.3; The Pasteur Culture Collection of Cyanobacteria) and 10 wt% gelatin are added to 1000 ml of A+ culture medium (containing 266 mg / L CaCk; UTEX Culture Collection of Algae) and heated to 35°C for 30 min. Then, 60 wt% kaolin (based on the gel mixture) is slowly added, and the mixture is stirred for 1 h.

[0125] The suspension is then poured into a geometric mold (L x W x H, 35 cm x 15 cm x 15 cm). OLED arrays are inserted into the mold before pouring. The OLEDs direct light into the interior of the mold and into the suspension.

[0126] The suspension containing the OLEDs is then cured inside the mold. The introduction of gaseous CO2 leads to the formation of calcium carbonate through MICP.

[0127] After curing, the mold is demolded.

[0128] The process of converting calcium into calcium carbonate can continue even after demoulding.

Claims

Patent claims 1. Process for the production of calcium carbonate materials or materials containing calcium carbonate, in which at least [amount] is required to achieve microbiologically induced calcium carbonate production. - a calcium-containing or calcium-containing material with pores, or a calcium-containing or calcium-containing material into which pores have been introduced and / or which are adjusted with regard to pore size, and / or - a non-calcium-containing or non-calcium-containing material with pores or into which pores have been introduced and / or adjusted with regard to pore size, or a lumpy or powdered non-calcium-containing material, is brought into contact with at least cyanobacteria in an environment containing carbon dioxide and water or water vapor, wherein at least in the case of the presence of only non-calcium-containing or non-calcium-containing material with at least the cyanobacteria, calcium-containing or calcium material is also introduced, and furthermore, at least light is introduced to enable photosynthesis by the cyanobacteria, and after the microbiologically induced calcium carbonate production, the produced calcium carbonate material or the produced calcium carbonate-containing material is finished or can be further processed.

2. The method according to claim 1, wherein natural calcium powders, calcium silicate powders, sand, recycled building materials, construction debris, mineral rocks, silicates, gravel, crushed stone, granites, basalts, clays, ceramic powders, polyurethanes are used as calcium-containing or calcium material and / or as non-calcium-containing or non-calcium material, and wherein, in the case of the introduction of non-calcium-containing or non-calcium material as starting materials, a calcium-containing or calcium material is introduced with the cyanobacteria.

3. The method of claim 2, wherein the liquid in which the cyanobacteria are located is the nutrient solution of the cyanobacteria, which in the case of the The introduction of calcium-containing or calcium material with the cyanobacteria also contains calcium-containing or calcium material.

4. The method of claim 1, wherein the introduction of pores or the adjustment of pore sizes in a calcium-containing or calcium material is achieved by introducing gases, such as carbon dioxide or carbon dioxide-containing gases, into the calcium-containing or calcium material, or by applying calcium-containing or calcium materials to foams, or by introducing placeholders that are subsequently removed, or by freeze-foaming.

5. Method according to claim 4, wherein the introduction of gases into the calcium-containing or calcium material is achieved by chemically or physically induced or pressure foaming, by stirring or by gas injection, for example by compressed air.

6. The method of claim 4, wherein calcium-containing or calcium materials are applied to foams made of polymers or ceramic materials and solidified on their surface, wherein the foam materials can subsequently be removed.

7. The method of claim 4, wherein a suspension is prepared from the calcium-containing or calcium material and / or from the non-calcium-containing or non-calcium material with a suspension medium, and this suspension is subjected to a vacuum and / or a temperature reduction, and the suspension medium is sublimed.

8. Method according to claim 1, wherein a pore size of the calcium-containing or calcium material or of the non-calcium-containing or non-calcium material of 0.3 to 10,000 pm, advantageously of 10 to 5,000 pm, or even more advantageously of 100 to 1,000 pm, is present, introduced or adjusted.

9. The method according to claim 1, wherein the calcium-containing or calcium-free material or the non-calcium-containing or non-calcium-free material predominantly open pores, preferably only open pores, are created and / or their pore size is adjusted.

10. Method according to claim 1, wherein ambient air or industrially produced gases, such as CO2 produced in industrial processes which may have been purified and concentrated, is used as the environment containing carbon dioxide and water or water vapor.

11. The method of claim 1, wherein a strain of Cyanoprokarvota is used as the cyanobacteria, the cyanobacteria also being used in combination with urease-producing and urea-degrading bacteria such as Helicobacter pylori, Klebsiella, Proteus, Staphylococcus saprophyticus, Yersinia or species of Enterobacter and Citrobacter.

12. Method according to claim 1, wherein cyanobacteria are used together with a nutrient solution for these cyanobacteria, wherein, at least in the case of the presence of only non-calcium-containing or non-calcium material, calcium-containing or calcium material is also introduced with the cyanobacteria via the nutrient solution.

13. The method of claim 1, wherein cyanobacteria are combined with at least one calcium-containing or calcium material and / or with at least one non-calcium-containing or non-calcium material or with a lumpy or powdered non-calcium-containing material, and with a material for immobilizing the cyanobacteria, wherein the materials for immobilizing the cyanobacteria are advantageously gels, gelatin, hydrogels, crosslinking and / or polymerizing and / or curing brines and / or additives.

14. Method according to claim 1, wherein light with a wavelength of 380 nanometers (nm) to 780 nm is introduced to the cyanobacteria to realize the photosynthesis of the cyanobacteria, wherein several wavelengths can also be used together, such as 660nm and 730nm.

15. Method according to claim 1, wherein sunlight and / or artificial light and / or light which can be realized via at least one light-conducting and light-emitting material or component is introduced as light for realizing the photosynthesis of the cyanobacteria.

16. Method according to claim 15, wherein light guides, optical fibers, LEDs, OLEDs, diodes, glass components are used as light-guiding and light-emitting materials or components.

17. Method according to claim 1, wherein light-conducting and light-emitting materials or components are introduced prior to, simultaneously with, or immediately following the introduction of pores and / or the adjustment with respect to a pore size in a calcium-containing or calcium material.

18. Method according to claim 1, wherein light-conducting and light-emitting materials or components are introduced prior to, simultaneously with, or immediately following the introduction of immobilizing materials for the cyanobacteria.

19. The method according to claim 1, wherein, after the microbiologically induced calcium carbonate production, the produced calcium carbonate-containing material is finished as a building material or further processed as a semi-finished product or further used as a building material.