Co-pyrolysis of biomass and mineral raw materials

Abstract

The present invention relates to a method for the co-pyrolysis of biomass and mineral raw materials for activating the mineral raw materials and to the use of the resulting pyrolysis product in the construction industry, in horticulture and landscaping, as a carrier and filter material, in energy storage technology, and as a CO2 sink.

Description

Co-pyrolysis of biomass and mineral raw materials The present invention relates to a process of copyrolysis of biomass and mineral raw materials for activation of the mineral raw materials and to the use of the pyrolysis product thus produced in the construction sector, in horticulture and landscaping, as carrier material and filter material, in battery technology, and as a CO2 sink. Technical backgroundIndustrially produced carbonisates, which can be obtained from a wide range of biomass sources such as waste wood, industrial scrap fibers, agricultural by-products and even algae, offer innovative solutions in modern construction. Said carbonisates can be used as environmentally sustainable components in buildings through their use as additives, binder component, cement substitute or fillers in both cement-based and cement-free building material systems. Their ability to store carbon dioxide in the form of carbon, said carbon dioxide having been absorbed by plants during plant growth, makes them a key element in the strategy to reduce the CO2 footprint in the construction industry. The use of carbonisates in building materials not only contributes to CO2 compensation, but also opens up ways for sustainable construction. They can create carbon sinks that help to reduce the global warming potential (GWP) value in building materials such as concrete. Furthermore, carbonisates can also adapt the technical properties or technical features of building materials. A major obstacle to the use of industrial carbonisates is their heterogeneity. Owing to the diversity of starting materials and different production processes, the end products have different properties, which in turn complicates standard-compliant and default integration into building material systems and production thereof. Furthermore, industrial carbonisates make the use of other raw materials more difficult. When used, for example, in concrete, there is the risk of reduced compressive strength. The production of carbonisates of consistent quality and in sufficient quantities is essential for industrial use. At present, this goal is being achieved by focusing efforts on optimizing pyrolysis technology, adjusting formulations, selecting suitable biomasses, and processing materials (e.g., activation). In addition, greater impetus is being given to the development of novel processes and technologies intended to maximize the performance and efficiency of carbonisates in various applications. The activation of mineral raw materials is crucial in the building materials industry, especially in the production of alternative binders and insulating materials. In order to make mineral raw materials such as clay minerals, vermiculites and perlites usable for technical applications in the construction industry, it is often the case that a high level of energy consumption is required. For example, kaolin, a clay mineral-containing raw material, is thermally activated in order to be able to be used as an alternative binder component in cement-based but also non-cement-based building material systems. This thermal treatment alters the chemical and physical structure of the material, as a result of which it becomes more reactive and thus more suitable as a binder component and can contribute to the development of strength in binder systems. The same applies to raw vermiculite and raw perlite, both of which expand at temperatures between about 700°C and 1000°C. This expansion leads to a significant increase in volume, which improves the insulating properties of these materials, and an associated improvement in the heat-insulating properties. Vermiculite, which has a high content of magnesium oxide, and perlite, which is rich in amorphous silica, are thus becoming efficient thermal insulation materials in the construction industry. However, a major problem with these processes is the high energy consumption. Activation, calcination and expansion require intensive heat treatment, which is often associated with a high level of consumption of fossil fuels and corresponding CO2 emissions. This is inconsistent with global efforts to reduce greenhouse gas emissions and to develop more sustainable methods of production. In order to meet this challenge, research is being conducted in the building materials industry on alternative technologies, especially in order to replace cement as the default building material with more sustainable and less energy-intensive materials. These include more energy-efficient calcination processes, the use of renewable energy sources, and the development of materials that can be activated at lower temperatures. Research is also being conducted on the recycling and treatment of by-products from other industries in order to reduce the demand for primary raw materials and the associated environmental impact. The aim of the ongoing research and development in this area is to minimize the environmental impact of the production of building materials while maintaining or even improving the quality and performance of the materials. Another aim is to provide durable building materials that can be integrated into a circular economy. This is an important step toward a more sustainable construction industry which acts responsibly both environmentally and economically. What are being sought are novel processes that take account of the developments in various sectors, in particular in the construction industry, and that yield novel materials which are based on renewable and ubiquitous raw materials and preferably contribute to reducing the CO2 footprint and to increasing the sustainability of various sectors. The energy expenditure of the novel processes should be as low as possible. The present invention relates to a process of copyrolysis of biomass and mineral raw materials for activation of mineral raw materials. What are formed at the same time during the copyrolysis are biomass carbonisate from the biomass and activated minerals from the mineral raw materials. It has been found that, surprisingly, the starting materials do not adversely affect either of the two reactions, i.e., the carbonization of the biomass and the activation of the mineral raw materials, and the two reactions proceed simultaneously. The mixed materials of biomass carbonisate and activated minerals preferentially obtained in this way from a single pyrolysis step can be used in many ways, for example in the construction sector, in horticulture and landscaping, as carrier material and filter material, in battery technology, or as sorption material. Owing to the use of biomass as starting material, the pyrolysis product obtained with the aid of the process according to the invention can contribute to CO2 compensation. The biomass may contain plant biomass, animal biomass and / or biogenic waste. The mineral raw materials used may be primary minerals, but also mineral waste products, for example from mining or from industrial processes. Therefore, the process according to the invention can also be used for the production of cost-effective materials while possibly avoiding supply chain problems. Summary of the inventionThe present invention relates to a process of copyrolysis of biomass and mineral raw materials for activation of the mineral raw materials, comprising the following steps:providing a mixture containing biomass and mineral raw materials in a weight ratio of biomass and mineral raw materials in the mixture in the range from 75 : 25 to 55 : 45, preferably 75 : 25 to 65 : 35, more preferably 73 : 27 to 67 : 33, even more preferably 72 : 28 to 66 : 32, most preferably 70 : 30, based on the total weight of the mixture of biomass and mineral raw materials;performing pyrolysis of the mixture containing biomass and mineral raw materials under low-oxygen conditions at a temperature in the range from 200°C to 1500°C, preferably from 250°C to 1250°C, most preferably from 300°C to 1100°C;obtaining a pyrolysis product containing biomass carbonisate and activated minerals. The present invention further relates to the use of the pyrolysis product produced by the process as described herein in the construction sector, for example as aggregate, binder, cement substitute or filler for building materials in cementitious building material systems, as additive, aggregate, binder, cement substitute or filler for building materials in building material systems with alkali-activated binders, as dye, as aggregate for improving hydration in flowable building materials and / or as aggregate for asphalt. The present invention additionally relates to the use of the pyrolysis product produced by the process as described herein in horticulture and landscaping, for example as plant substrate, as aggregate for base mix concrete, as gap fill, in palisades, as bedding material, as insulation material, possibly in combination with loam, in tree grates, in dike or dam construction and / or for greening roofs and facades.  The present invention moreover relates to the use of the pyrolysis product produced by the process as described herein as carrier material and / or filter material, for example as carrier material for catalysts, as filter material for waste gases or liquid waste streams, as drying agent, as compensatory and adsorption material for slags and / or as absorber for contaminants and pollutants.  The present invention further relates to the use of the pyrolysis product produced by the process as described herein in energy storage technology, for example in capacitors.  The present invention lastly relates to the use of the pyrolysis product produced by the process as described herein as a CO2 sink. The term "copyrolysis" in the context of the process according to the invention means a single pyrolysis step under low-oxygen conditions in a certain temperature range and over a certain period in which conversion of biomass into biomass carbonisate and activation of the mineral raw materials occur at the same time and under the same conditions. The term "copyrolysis" excludes process steps in which conversion of biomass into biomass carbonisate and activation of the mineral raw materials occur at different times and / or locations. Description of the inventionThe present invention relates to a process of copyrolysis of biomass and mineral raw materials for activation of the mineral raw materials, comprising the following steps:providing a mixture containing biomass and mineral raw materials in a weight ratio of biomass and mineral raw materials in the mixture in the range from 75 : 25 to 55 : 45, preferably 75 : 25 to 65 : 35, more preferably 73 : 27 to 67 : 33, even more preferably 72 : 28 to 66 : 32, most preferably 70 : 30, based on the total weight of the mixture of biomass and mineral raw materials;performing pyrolysis of the mixture containing biomass and mineral raw materials under low-oxygen conditions at a temperature in the range from 200°C to 1500°C, preferably from 250°C to 1250°C, most preferably from 300°C to 1100°C;obtaining a pyrolysis product containing biomass carbonisate and activated minerals. The weight ratio of biomass and mineral raw materials in the mixture is in the range from 75 : 25 to 55 : 45, preferably 75 : 25 to 65 : 35, more preferably 73 : 27 to 67 : 33, even more preferably 72 : 28 to 66 : 32, most preferably 70 : 30, based on the total weight of the mixture of biomass and mineral raw materials. It has been found that, surprisingly, a mixture in this weight ratio has higher reactivity than mixtures having a higher or lower weight ratio. Furthermore, the pyrolysis product produced from a mixture in this weight ratio surprisingly exhibits better mechanical properties, especially in respect of compressive and flexural strengths, compared to pyrolysis products produced from a mixture with lower weight ratios.  The biomass and the mineral raw materials are preferably in the form of solids, for example in the form of granules, powders, grains, briquettes, pellets, ground material, cut material, chopped material, pieces of wood, broken pieces, balls, flakes or in a similar form.The particle size is usually in the range from 0.01 to 1000 mm, preferably 0.1 to 300 mm. Before or after mixing, the biomass and the mineral raw materials can be brought into the desired form by appropriate shaping methods, for example by grinding, pelletizing, pressing, cutting, chopping or similar customary shaping methods. What is selected depends on the particular starting materials and the desired form and is within the normal expertise of a person skilled in the art.However, it is preferable, usually for cost reasons, for the biomass and the mineral raw materials to remain in their original form. The mixture of biomass and mineral raw materials usually contains a water content of less than 50% by weight, preferably in the range from 0% to 40% by weight, more preferably in the range from 0% to 30% by weight, most preferably in the range from 0% to 25% by weight, based on the total weight of the mixture. The water content of the mixture of biomass and mineral raw materials can, if necessary, be lowered by drying the mixture or the individual starting materials before mixing. The biomass preferably contains plant biomass, preferably lignin- and / or cellulose-containing biomass such as wood and bamboo, agricultural products, green cuttings, algae, aquatic plants and mixtures thereof, especially lignin- and / or cellulose-containing biomass such as wood and bamboo, agricultural products and mixtures thereof. The biomass may also contain animal biomass, for example slaughterhouse waste.Furthermore, the biomass may also contain biogenic waste, i.e., biogenic materials which have already gone through one cycle of use, such as waste wood and agricultural waste, sludges, such as sewage sludge, compost, scrap fibers and mixtures thereof. The biomass is preferably obtained from agricultural by-products, wood industry and forestry by-products, biogenic municipal waste, waste from other lands and clear sludge and also industrial waste and waste from energy production. Agricultural by-products are in particular harvest waste, such as straw, leaves or husks, animal excrement and excess biomass. Wood industry and forestry by-products are in particular industrial wood waste, which may also contain waste wood, scrap wood from wood processing, bark, sawdust, wood dust, branches and residual crowns after timber harvesting and by-products from pulp production. Biogenic municipal waste, waster from other lands and clear sludge are in particular biomass from land management and land along paths, green cuttings, green waste, sewage sludge from wastewater treatment plants, and biomass from bodies of water. Industrial waste and waste from energy production are in particular by-products from biodiesel and bioethanol production, biogenic waste from the paper and pulp industry, waste from the food industry, waste from the feed industry and general production waste such as husks, pomace, fats and whey. It is particularly preferable that the biomass contains lignin- and / or cellulose-containing biomass such as wood, bamboo, agricultural products and mixtures thereof. The proportion of plant biomass in the biomass is usually at least 50% by weight, for example 50% to 100% by weight, preferably 75% to 100% by weight, more preferably 85% to 100% by weight. In a specific embodiment, the biomass contains 90% to 100% by weight of lignin-containing biomass, for example 95% to 100% by weight of lignin-containing biomass. Depending on its origin, the biomass may also contain foreign matter, such as plastic, metal, salts or the like. The proportion of foreign matter in the biomass is usually in the range from 0% to 50% by weight, preferably 0% to 30% by weight.  The mineral raw materials preferably contain clay minerals, for example vermiculite, kaolinite or illite, minerals of the olivine group, for example forsterite, minerals of the mica group, for example muscovite or biotite, volcanic rocks, for example perlite, and mixtures thereof. Suitable minerals of the mica group are, for example, muscovite or biotite.Suitable volcanic rocks are, for example, perlite.Suitable minerals of the olivine group are, for example, forsterite.Suitable clay minerals are, for example, vermiculite, kaolinite and illite. Also suitable are kaolinites having a low kaolin content of, for example, less than 70% by weight, based on the total weight of kaolinite. Said kaolinites having a low kaolin content are obtained, for example, as secondary raw material in large amounts and are not suitable for ceramic and paper production. The mineral raw materials may contain primary minerals, mineral waste products, for example from mining or from industrial processes, or mixtures thereof. The mineral raw materials are preferably composed of clays and waste from clay production, waste from feldspar production, excavated soil, waste from kaolin and clay production, such as mica-containing residues, for example muscovite, and clay-containing slurries, kaolin-containing slurries from ceramic and pulp production and paper production, kaolin-containing slurries from tile and brick production, kaolin-containing slurries from the plastics and paint industry, mineral-containing sewage sludges, mineral-containing sludges from water treatment, red mud, cement fiberboards, vermiculite waste, perlite waste, mineral-containing testers from the food industry, material from deconstruction and demolition of buildings and infrastructure such as bricks, waste from magnesite and dolomite production, waste from mining, raw material extraction and product processing such as overburden and spoil tip material, treatment residues from ore processing, waste from the chemical industry and metallurgy and waste from limestone processing. Preferably, the mineral raw materials contain a calcium carbonate content of less than 10% by weight, for example of 0% to 7.5% by weight, preferably 0% to 5.0% by weight, more preferably 0% to 2.5% by weight, based on the total weight of the mineral raw materials. The mixture may contain foreign matter, such as plastic, metal, salts or the like, in a proportion of 0% to 40% by weight, preferably 0% to 25% by weight. Said foreign matter usually originates from the biomass and entered the biomass, for example, during the use cycle and processing cycle. The mixture may be premixed and introduced as a mixture into a pyrolysis furnace. An alternative possibility is to first initially charge one component of the mixture, usually the biomass, into the pyrolysis furnace and then add the second component, usually the mineral raw materials, to the first component in the pyrolysis furnace. After the mixture containing biomass and mineral raw materials has been prepared, it is subjected to pyrolysis.The pyrolysis is usually effected in a pyrolysis furnace.To this end, the mixture is exposed to a temperature in the range from 200°C to 1500°C, preferably from 250°C to 1250°C, most preferably from 300°C to 1100°C, under low-oxygen conditions."Low-oxygen conditions" means oxygen levels in the pyrolysis furnace during the pyrolysis step of 0% to 20% by volume, preferably 0% to 10% by volume. The oxygen can originate from the gas phase in the pyrolysis furnace or can be formed from the mixture by chemical reaction during the pyrolysis. The duration of the pyrolysis is usually in the range from 1 second (flash pyrolysis) to 3 days, depending on the type of pyrolysis. Preferably, the duration of the pyrolysis is 1 minute to 10 hours, preferably 15 minutes to 4 hours. The pyrolysis is usually carried out at a pressure in the range from 0 to 5 bar(g), preferably from 0 to 1 bar(g), more preferably at 0 bar(g). The pyrolysis is usually carried out in a pyrolysis furnace, for example a pyrolysis reactor, rotary furnace, biomass burner, following conversion if necessary, or a gas generator.  The process according to the invention may comprise one or more pyrolysis steps which are carried out one after the other.  To this end, in one embodiment, the mixture is first subjected to a first pyrolysis step. After said first pyrolysis step, the mixture can be subjected to one or more further pyrolysis steps one after the other. The pyrolysis conditions here may differ from the preceding pyrolysis steps within the abovementioned ranges. Usually, not more than 4 pyrolysis steps are carried out one after the other. In a further embodiment, one component, usually the biomass, is torrefied in a first step. The torrefied component is then mixed with the second component, usually the mineral raw materials. This mixture is then subjected to one or more pyrolysis steps. The torrefication conditions and the conditions of the subsequent pyrolysis steps may differ from the preceding pyrolysis steps within the abovementioned ranges. Usually, not more than 4 torrefication and pyrolysis steps are carried out one after the other. In one of these multiple pyrolysis steps, preferably the last pyrolysis step, the biomass, preferably the pyrolyzed biomass, may be gasified. The gasification conditions may differ from the preceding pyrolysis steps within the abovementioned ranges. In a further embodiment, a single pyrolysis step is carried out in the process according to the invention. Different reactions take place during the pyrolysis. The pyrolysis usually takes place under autothermal conditions. Here, constituents of the biomass, preferably highly volatile constituents of the biomass, serve as fuel for the pyrolysis. This can reduce the use of external fuels. External fuel is usually required to start the pyrolysis reaction. During the pyrolysis, external fuel can usually be dispensed with.  The external fuel for the pyrolysis is usually selected from fossil fuels, for example natural gas, oil and coal, preferably natural gas, and renewable fuels, for example hydrogen, bioalcohols, biogas, vegetable oil and wood materials, and mixtures thereof. To increase the sustainability of the process according to the invention, it is desirable to transition to higher proportions of renewable fuels. The biomass is carbonized to biomass carbonisate. What occurs here at the elevated temperatures of pyrolysis is decomposition of the biomass constituents, for example of lignin, cellulose and hemicellulose in the case of wood, into smaller molecules, such as carbon, liquid pyrolysis oil and gaseous pyrolysis gas. The liquid and gaseous constituents are preferably at least partly separated from the solid constituents after the pyrolysis step. Most liquid constituents become gaseous under pyrolysis conditions and are separated from the solid constituents together with the gaseous constituents.The gaseous constituents can be used as fuel in the pyrolysis. This reduces the use of external fuel sources.The biomass carbonisate preferably contains a carbon content of at least 1% by weight, for example in the range from 1% to 95% by weight, in particular in the range from 10% to 90% by weight, based on the total weight of the biomass carbonisate.  The mineral raw materials become activated. The form of activation depends on the nature of the mineral raw materials, the temperature range and the energy input.Certain minerals are activated by transformation. For instance, certain clay minerals are transformed, for example kaolinite into metakaolin. Here, the OH groups of the clay minerals present are split off at the elevated temperatures of the pyrolysis (dehydroxylation). This considerably increases the solubility of silicon and aluminum ions in an alkaline medium. This endothermic reaction usually requires activation energies in the range from 100 to 200 kJ / mol.Carbonate-containing materials are transformed into the corresponding oxides.Other clay minerals, for example vermiculite, and volcanic rocks, for example perlites, expand at the elevated temperatures of pyrolysis. The expansion increases the pore volume of the expanded minerals. At the same time, the chemically and physically bound water is converted into the gas phase. This endothermic reaction usually requires activation energies in the range from 10 to 50 kJ / mol. During and / or after the pyrolysis step, the liquid and gaseous pyrolysis products are usually separated from the solid pyrolysis products. The liquid and gaseous pyrolysis products can be used, for example, as energy carriers and / or as fuel for the pyrolysis. A further product of the process according to the invention is usually a solid pyrolysis product containing biomass carbonisate and activated minerals. The pyrolysis product can be shaped by the customary methods of shaping according to its field of use.Here, the pyrolysis product may also be mixed and shaped with other materials. To this end, in one embodiment, water saturation, as is customary today, may be dispensed with.The pyrolysis product may be used in solid form or in the form of a slurry, for example a suspension in water. The pyrolysis products obtained by the process according to the invention are usable in a variety of ways. For instance, the pyrolysis products obtained by the process according to the invention can be used in the construction sector.  For example, the pyrolysis products obtained by the process according to the invention may be used as additive, aggregate, binder, cement substitute or filler for building materials in cementitious building material systems, as aggregate, binder, cement substitute or filler for building materials in building material systems with alkali-activated binders, as dye, as aggregate for improving hydration in flowable building materials and / or as aggregate for asphalt. It is found that the pyrolysis products obtained by the process according to the invention have increased reactivity and improved integration into building material systems compared to pure industrial carbonisates owing to a higher ash content and the higher mineral content.Besides more efficient use of the carbonisates, especially when clay minerals such as kaolinite are used in the pyrolysis products obtained by the process according to the invention, there might also be the potential to reduce the demand for cement, thus making the production of building materials more sustainable. The pyrolysis products obtained by the process according to the invention can be used, for example, in so-called LC3 cements, thereby allowing a considerable reduction in the clinker content of cement. The reason for this is that the calcined clay minerals exhibit an increased solubility of silicon and aluminum ions in an alkaline medium and the ions released react, inter alia, with calcium hydroxide in the hydrating cement and form additional hydrate phases which contribute to the development of strength.In the case of use of vermiculite and volcanic rocks, such as perlite, in the pyrolysis products obtained by the process according to the invention, the expansion of these minerals makes it possible to obtain building materials having a low particle density and good thermal and acoustic insulation properties. Examples are structural lightweight concrete. Furthermore, the pyrolysis products obtained by the process according to the invention can be used in horticulture and landscaping. For example, the pyrolysis products obtained by the process according to the invention may be used as plant substrate, as aggregate for base mix concrete, as gap fill, in palisades, as bedding material, as insulation material, possibly in combination with loam, in tree grates, in dike or dam construction and / or for greening roofs and facades. Moreover, the pyrolysis products obtained by the process according to the invention can be used as carrier material and / or filter material. For example, the pyrolysis products obtained by the process according to the invention may be used as carrier material and / or filter material, for example as carrier material for catalysts, as filter material for waste gases or liquid waste streams, as drying agent, as compensatory and adsorption material for slags and / or as absorber for contaminants and pollutants. In addition, the pyrolysis products obtained by the process according to the invention can be used in energy storage technology, for example in capacitors. Lastly, the pyrolysis products obtained by the process according to the invention can be used as a CO2 sink. ExamplesMixtures of softwood as biomass component and kaolin-containing production waste as mineral raw material having a proportion by weight of kaolin-containing production waste in the range from 10% by weight to 30% by weight were copyrolyzed at temperatures of 650°C and 750°C. Mineralogical analyses using an X-ray diffractometer revealed successful transformation of kaolinite (crystalline) into metakaolin (amorphous) in the experiments and thus phase transformation of the mineral due to the copyrolysis. In addition, the carbon products of the copyrolysis of softwood and kaolin-containing production waste had a reactivity well above the reactivity of customary plant carbon, as shown by an R3 test using a calorimeter. Here, the carbon products produced from mixtures of clay to biomass in the ratio of 23 : 77, 30 : 70 and 50 : 50 were compared with one another. The copyrolysis was effected at 650°C for 15 min. The chemical composition of the carbon products measured by X-ray fluorescence analysis (XRF) and the loss of ignition (LOI) are listed in the following table: Table: Chemical composition and loss of ignition for different weight ratiosWeight ratio of clay : biomass23 : 7730 : 7050 : 50LOI [%]45.025.119.9Composition:   Al2O3 [%]21.2229.4531.98SiO2 [%]28.9939.7342.64P2O5 [%]0.290.21-K2O [%]1.602.042.13CaO [%]0.560.500.50TiO2 [%]0.510.720.70MnO [%]0.070.050.05CuO [%]-0.02-Fe2O3 [%]--1.48ZnO [%]--0.02Rb2O [%]-0.010.01SnO2 [%]0.570.690.64 A calorimeter determines the heat of reaction released by a material by measuring the heat flow generated in physical or chemical processes. The R3 test is arapid, relevant and reliable (= R3) method for evaluating the pozzolanic reactivity of calcined clays and other cement substitutes. Reference:Avet, François; Snellings, Ruben; Alujas Diaz, Adrian; Ben Haha, Mohsen; Scrivener, Karen (2016): Development of a new rapid, relevant and reliable (R3) test method to evaluate the pozzolanic reactivity of calcined kaolinitic clays. In: Cement and Concrete Research 85, pp. 1–11. DOI: 10.1016 / j.cemconres.2016.02.015. Figure 1 shows the result of the R3 test for carbon products produced from mixtures of clay to biomass in the ratio of 23 : 77, 30 : 70 and 50 : 50 compared to reference products such as calcined clay, slag sand, fly ash and quartz. It was found that, surprisingly, the carbon product produced from a mixture of clay to biomass in the ratio of 30 : 70 has the highest reactivity. The carbon product produced from a mixture of clay to biomass in the ratio of 30 : 70 is about 20% more reactive than the carbon product produced from a mixture of clay to biomass in the ratio of 50 : 50 and about 40% more reactive than the carbon product produced from a mixture of clay and biomass in the ratio of 23 : 77. The carbon products produced from mixtures of clay to biomass in the ratio of 30 : 70 and 50 : 50 were used in mortar prisms as cement substitute (10%). The mortar prisms were subjected to compressive strength tests and flexural strength tests in accordance with DIN EN 1015-11 after 7 days and 28 days and compared with mortar prisms containing 10% cement as standard. The results are shown in Figures 2 and 3.The mortar prisms containing 10% carbon product produced from a mixture of clay to biomass in the ratio of 30 : 70 generally have a higher compressive strength and flexural strength than mortar prisms containing 10% carbon product produced from a mixture of clay to biomass in the ratio of 50 : 50. The compressive strengths of the mortar prisms containing 10% carbon product produced from a mixture of clay to biomass in the ratio of 30 : 70 are comparable with the compressive strengths of the standard mortar prisms. The 28-day values for the flexural strengths of the mortar prisms containing 10% carbon product produced from a mixture of clay to biomass in the ratio of 30 : 70 surpass those of the standard mortar prisms. 

Claims

1.A process of copyrolysis of biomass and mineral raw materials for activation of the mineral raw materials, comprising the following steps:providing a mixture containing biomass and mineral raw materials in a weight ratio of biomass and mineral raw materials in the mixture in the range from 75 : 25 to 55 : 45, preferably 75 : 25 to 65 : 35, more preferably 73 : 27 to 67 : 33, even more preferably 72 : 28 to 66 : 32, most preferably 70 : 30, based on the total weight of the mixture of biomass and mineral raw materials;performing pyrolysis of the mixture containing biomass and mineral raw materials under low-oxygen conditions at a temperature in the range from 200°C to 1500°C, preferably from 250°C to 1250°C, most preferably from 300°C to 1100°C;obtaining a pyrolysis product containing biomass carbonisate and activated minerals. 2.The process as claimed in claim 1, wherein the mineral raw materials contain clay minerals, for example vermiculite, kaolinite or illite, minerals of the mica group, for example muscovite or biotite, volcanic rocks, for example perlite, minerals of the olivine group, for example forsterite, and mixtures thereof.3.The process as claimed in either of the preceding claims, wherein the biomass contains plant biomass, preferably lignin- and / or cellulose-containing biomass such as wood and bamboo, agricultural products, green cuttings, algae, aquatic plants and mixtures thereof, animal biomass, preferably slaughterhouse waste, biogenic waste, preferably waste wood and agricultural waste, sludges, such as sewage sludge, compost, scrap fibers and mixtures thereof.4.The process as claimed in any of the preceding claims, wherein the biomass is obtained from agricultural by-products, wood industry and forestry by-products, biogenic municipal waste, waste from other lands and clear sludge and also industrial waste and waste from energy production.5.The process as claimed in any of the preceding claims, wherein the biomass and the mineral raw materials are in the form of solids. 6.The process as claimed in any of the preceding claims, wherein the mixture of biomass and mineral raw materials contains a water content of less than 50% by weight, preferably in the range from 0% to 40% by weight, more preferably in the range from 0% to 30% by weight, most preferably in the range from 0% to 25% by weight, based on the total weight of the mixture. 7.The process as claimed in any of the preceding claims, wherein the pyrolysis takes place under autothermal conditions.8.The process as claimed in any of the preceding claims, wherein the minerals are activated by transformation, for example by dehydroxylation.9.The process as claimed in any of the preceding claims, wherein kaolinite is activated by transformation into metakaolin.10.The process as claimed in any of the preceding claims, wherein the minerals are activated by expansion, for example the expansion of perlite and / or vermiculite.11.The use of the pyrolysis product produced by the process as claimed in any of the preceding claims in the construction sector, for example as additive, aggregate, binder, cement substitute or filler for building materials in cementitious building material systems, as aggregate, binder, cement substitute or filler for building materials in building material systems with alkali-activated binders, as dye, as aggregate for improving hydration in flowable building materials and / or as aggregate for asphalt.12.The use of the pyrolysis product produced by the process as claimed in any of claims 1 to 10 in horticulture and landscaping, for example as plant substrate, as aggregate for base mix concrete, as gap fill, in palisades, as bedding material, as insulation material, preferably in combination with loam, in tree grates, in dike or dam construction and / or for greening roofs and facades.13.The use of the pyrolysis product produced by the process as claimed in any of claims 1 to 10 as carrier material and / or filter material, for example as carrier material for catalysts, as filter material for waste gases or liquid waste streams, as drying agent, as compensatory and adsorption material for slags and / or as absorber for contaminants and pollutants.14.The use of the pyrolysis product produced by the process as claimed in any of claims 1 to 10 in energy storage technology, for example in capacitors.15.The use of the pyrolysis product produced by the process as claimed in any of claims 1 to 10 as a CO2 sink.                      Abstract:   The present invention relates to a method for the co-pyrolysis of biomass and mineral raw materials for activating the mineral raw materials and to the use of the resulting pyrolysis product in the construction industry, in horticulture and landscaping, as a carrier and filter material, in energy storage technology, and as a CO2 sink.  Claims 1.A process of copyrolysis of biomass and mineral raw materials for activation of the mineral raw materials, comprising the following steps:providing a mixture containing biomass and mineral raw materials in a weight ratio of biomass and mineral raw materials in the mixture in the range from 75 : 25 to 55 : 45, preferably 75 : 25 to 65 : 35, more preferably 73 : 27 to 67 : 33, even more preferably 72 : 28 to 66 : 32, most preferably 70 : 30, based on the total weight of the mixture of biomass and mineral raw materials;performing pyrolysis of the mixture containing biomass and mineral raw materials under low-oxygen conditions at a temperature in the range from 200°C to 1500°C, preferably from 250°C to 1250°C, most preferably from 300°C to 1100°C;obtaining a pyrolysis product containing biomass carbonisate and activated minerals.  2.The process as claimed in claim 1, wherein the mineral raw materials contain clay minerals, for example vermiculite, kaolinite or illite, minerals of the mica group, for example muscovite or biotite, volcanic rocks, for example perlite, minerals of the olivine group, for example forsterite, and mixtures thereof. 3.The process as claimed in either of the preceding claims, wherein the biomass contains plant biomass, preferably lignin- and / or cellulose-containing biomass such as wood and bamboo, agricultural products, green cuttings, algae, aquatic plants and mixtures thereof, animal biomass, preferably slaughterhouse waste, biogenic waste, preferably waste wood and agricultural waste, sludges, such as sewage sludge, compost, scrap fibers and mixtures thereof. 4.The process as claimed in any of the preceding claims, wherein the biomass is obtained from agricultural by-products, wood industry and forestry by-products, biogenic municipal waste, waste from other lands and clear sludge and also industrial waste and waste from energy production. 5.The process as claimed in any of the preceding claims, wherein the biomass and the mineral raw materials are in the form of solids.  6.The process as claimed in any of the preceding claims, wherein the mixture of biomass and mineral raw materials contains a water content of less than 50% by weight, preferably in the range from 0% to 40% by weight, more preferably in the range from 0% to 30% by weight, most preferably in the range from 0% to 25% by weight, based on the total weight of the mixture.  7.The process as claimed in any of the preceding claims, wherein the pyrolysis takes place under autothermal conditions. 8.The process as claimed in any of the preceding claims, wherein the minerals are activated by transformation, for example by dehydroxylation. 9.The process as claimed in any of the preceding claims, wherein kaolinite is activated by transformation into metakaolin. 10.The process as claimed in any of the preceding claims, wherein the minerals are activated by expansion, for example the expansion of perlite and / or vermiculite. 11.The use of the pyrolysis product produced by the process as claimed in any of the preceding claims in the construction sector, for example as additive, aggregate, binder, cement substitute or filler for building materials in cementitious building material systems, as aggregate, binder, cement substitute or filler for building materials in building material systems with alkali-activated binders, as dye, as aggregate for improving hydration in flowable building materials and / or as aggregate for asphalt. 12.The use of the pyrolysis product produced by the process as claimed in any of claims 1 to 10 in horticulture and landscaping, for example as plant substrate, as aggregate for base mix concrete, as gap fill, in palisades, as bedding material, as insulation material, preferably in combination with loam, in tree grates, in dike or dam construction and / or for greening roofs and facades. 13.The use of the pyrolysis product produced by the process as claimed in any of claims 1 to 10 as carrier material and / or filter material, for example as carrier material for catalysts, as filter material for waste gases or liquid waste streams, as drying agent, as compensatory and adsorption material for slags and / or as absorber for contaminants and pollutants. 14.The use of the pyrolysis product produced by the process as claimed in any of claims 1 to 10 in energy storage technology, for example in capacitors. 15.The use of the pyrolysis product produced by the process as claimed in any of claims 1 to 10 as a CO2 sink. 

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