Cement-based composition comprising slag and biochar

Abstract

The invention relates to a cementitious composition which is a dry mortar comprising slag, at least one hydraulic binder and / or at least one activator, biochar particles and fine aggregate, the weight ratio of biochar to blast furnace slag ranging from 0.025: 1 to 0.15: 1. The invention further relates to a mortar prepared by combining a cementitious composition with water, to the use thereof and to a method for preparing the mortar. The invention further relates to the use of biochar to reduce the odor of slag in a mortar composition.

Description

[0001] The present invention relates to a cementitious composition which is a dry mortar and which comprises: slag, at least one hydraulic binder and / or at least one activator, biochar particles and fine aggregate, wherein the weight ratio of biochar to slag ranges from 0.025:1 to 0.15:1. The present invention further relates to a mortar prepared by combining the cementitious composition with water, a method for preparing such mortar and its uses. The present invention further relates to the use of biochar for reducing the odour of slag in a mortar composition. Background Art

[0002] The present invention relates to mortars. A mortar is a mixture comprising a hydraulic binder and particles (also known as aggregates) and optionally various additives. After mixing with water, a wet paste or mortar is obtained which can be shaped before hardening, for example applied to a support. Thus, the final product or hardened mortar obtained consists of particles bonded by a mineral binder obtained by the hydration of the hydraulic binder. Mortars are conventionally used in the construction and public works fields to form exterior wall coatings or floor coverings, as tiling adhesives, as grouting mortars, as mortars for repairing concrete works, etc.

[0003] One of the problems currently of concern remains the significant reduction of the carbon footprint in the construction industry, especially in view of the RE2020 standard which came into force in 2022. Traditional mortars contain Portland cement or high alumina cement as hydraulic binders, both of which are based on ground clinker mixed with additives such as gypsum. The manufacture of clinker requires the decarbonization, calcination and hydration of limestone and clay or bauxite in a kiln heated to 1,450 °C. For example, Portland cement and high alumina cement are sources of emissions of approximately 800 kg of CO 2 per tonne of cement prepared, mainly due to the decarbonization of limestone and the combustion of fossil materials used to heat the kiln. The applicant has already proposed alternative solutions for these cements in WO 2019 / 086780, wherein the hydraulic binder is based on slag, which is a by-product of this industry. The method for preparing slag generates less CO 2 and thus enables the carbon balance of the mortar thus prepared to be improved.

[0004] In WO 2019 / 086780, the slag is derived from the recycling by complete melting of desulfurization catalysts for petroleum products (especially catalysts based on molybdenum and / or cobalt). It has also been proposed to use blast furnace slag to reduce the amount of clinker in cement. Thus, cements CEMII / A-S, CEMII / B-S, CEMIII and CEM V contain different amounts of blast furnace slag in addition to clinker. Recent work has shown that more than 95% of Portland cement can be replaced by ground granulated blast furnace slag. Mention may be made, for example, of FR 2 952 050 and US 6,409,820, which describe binders based on ground granulated blast furnace slag that can be used under "mild" conditions, that is to say without the use of a highly alkaline activator system and thus without danger during operation.

[0005] One drawback of blast furnace slag is that it contains sulfur mainly in the form of sulfides. When blast furnace slag comes into contact with an acidic environment, hydrogen sulfide may be released therefrom. As is well known, this sulfur compound has an unpleasant odor, similar to that of rotten eggs, and even becomes poisonous when present at high concentrations. The olfactory detection threshold is very low, and the presence of this gas can be detected from 0.0005 ppm, while the lethal threshold is about 800 ppm. This latter concentration level is never reached in building materials. However, the odor can be discomforting because it is very strong and can be detected even at very low concentrations.

[0006] To eliminate or limit the problems involved with the unpleasant odor associated with binders based on blast furnace slag, the applicant has proposed in WO 2014 / 013199 to mix a metal salt of a monovalent, divalent or trivalent salt selected from the group consisting of bismuth, copper, silver or tin with the slag. When placed in the presence of a binder based on blast furnace slag, the metal salt reacts with the sulfur compound to form a complex sulfide, which then precipitates and remains in solid form. The fact is that the product obtained is extremely poorly soluble, thus making it possible to capture the compounds responsible for the foul odor. However, the use of metal compounds affects the cost of these binders and, in some cases, raises environmental problems. First of all, the amount of salt should be low enough so as not to interfere with the hydration of the cement. This low amount usually results in insufficient reduction of the foul odor over time.

[0007] There is still a need for effective ways to reduce the odor when using a high proportion of blast furnace slag in mortar compositions without adversely affecting the properties of the hardened mortar, especially its dry and wet tensile strengths and its tensile strength after 30 minutes of open time, and without adversely affecting the economy of its preparation method.

[0008] The present inventors have now shown that a cement-based composition containing a specific proportion of biochar can meet this need.

[0009] Biochar is produced by the partial pyrolysis of biomass at 400 - 800 °C in a low-oxygen atmosphere. Biomass itself is derived from sugars and oxygen, which are the products of plants absorbing carbon dioxide and water through photosynthesis. Since they have been converted into biomass and subsequently into biochar, the sugars and oxygen cannot be reconverted back into carbon dioxide through the plant's respiratory cycle. Thus, carbon dioxide is captured in biochar, and biochar is thereby regarded as a "CO 2 absorbent". The carbon content of biochar accounts for more than 90% of its weight and corresponds to the CO 2 removed by plants from the atmosphere. It is calculated that biochar has a negative carbon dioxide footprint, which is approximately -3 kg CO 2 / kg of biochar.

[0010] It has been proposed to use biochar in the manufacture of artificial aggregates for concrete (CN114538850) to make up for the insufficient strength of permeable concrete and absorb pollutants and contaminants (CN108623248, CN114804734), to reduce the shrinkage of alkali-activated slag paste (J. Prabahar et al., Constr. Mater. 2022, 2, 1 - 14) or increase the strength of mortar (D. Suarez-Riera et al., Procedia Structural Integrity 26 (2020) 199 - 210). US2022 / 0298073 further suggests using at least 2 wt% of biochar in a hydraulic binder containing cement, not only reducing the amount of cement in the mortar composition but also sequestering carbon within the cement matrix, thereby reducing carbon emissions into the atmosphere. Here, "cement" refers to Portland cement or non-Portland cement, such as slag-based cement, although only Portland cement was used in the examples of US2022 / 0298073. In addition, this document does not address the problem of slag odor and thus does not indicate that biochar may have any positive effect on it. Moreover, it does not show that adding a specific proportion of biochar to slag-based mortar will effectively reduce the odor of slag. The same applies to the recently introduced hydraulic binder based on clinker and biochar by VICAT. Similarly, DE 10 2021 001327 further suggests adding biochar to concrete formulations to reduce the latter's environmental impact. Summary of the Invention

[0011] The present invention relates to a cement-based composition comprising:

[0012] - slag,

[0013] - at least one hydraulic binder and / or at least one activator,

[0014] - biochar particles, and

[0015] - aggregates,

[0016] wherein the weight ratio of biochar to slag ranges from 0.025:1 to 0.15:1,

[0017] characterized in that the composition is a dry mortar, and the aggregates have a diameter of less than 8 mm and comprise sand.

[0018] The present invention also relates to a mortar prepared by combining the cement-based composition as described above with water, preferably the weight ratio of water to the cement-based composition ranges from 20% to 40%, preferably from 25% to 30%.

[0019] The present invention further relates to a method for preparing a mortar, which comprises mixing the cement-based composition as described above with water, preferably the weight ratio of water to the composition ranges from 20% to 40%, preferably from 25% to 30%.

[0020] The present invention still further relates to the following uses of the mortar: manufacturing tile adhesives, such as adhesives for bonding ceramic or glass tiles or joints; assembling building components, such as masonry mortar; as exterior wall mortar, such as rendering mortar, primer coat, single-coat base coat, organic finish mortar, interior wall plaster, insulating mortar and waterproof mortar; as floor mortar; or as repair mortar, such as injection mortar.

[0021] The present invention further relates to the use of biochar to reduce the odor of slag in the mortar composition, both before and after hardening. Detailed Description

[0022] The present invention relates to a cement-based composition. By this expression, it means a powdery mixture, all of whose components are in solid form, usually in the form of powder and / or granules. The composition usually contains less than 5% by weight of water, such as less than 3% by weight of water or even less than 1% by weight of water, and when mixed with water, it is capable of forming a paste or slurry that hardens when exposed to air.

[0023] The composition contains slag. As used in the present invention, "slag" refers to a by-product of an industrial process that implements the melting of starting materials, which melting aims to separate metals from oxide phases, the latter being called "slag". Slag is usually quenched in water to obtain amorphous particles, which are then ground to activate them. Preferably, the slag used in the present invention is selected from slags produced by metallurgical processes, such as blast furnace slag, oxygen steel furnace slag, electric furnace slag and mixtures thereof.

[0024] Blast furnace slag is a by-product resulting from the production of a melt from iron ore; it corresponds to sterile gangue separated from liquid cast iron by density differences. The molten slag is lighter and floats on the liquid steel bath. Blast furnace slag mainly contains aluminosilicates and contains small amounts of sulfides. The slag obtained by quenching the molten slag or by tempering with air and / or high-pressure water jets has a vitreous structure. This results in granulated slag with hydraulic properties and a particle size of less than 5 mm. These slag particles can be crushed after drying and used in the present invention. Most ground granulated blast furnace slag has a fineness of 3,800 to 4,500 cm 2 / gm (also expressed in Blaine units).

[0025] In the above process, the liquid cast iron is further processed in an oxygen furnace or a conversion unit to produce liquid steel, which is then separated from the slag. The latter is called oxygen steel furnace slag (LD / LWS / OBM) and can also be used in the present invention. If an electric arc furnace is used instead of the oxygen conversion unit, another type of slag can be obtained, which is called electric arc furnace slag (LAFE).

[0026] Most preferably, the slag used in the present invention is blast furnace slag because it is the most common.

[0027] Relative to the total weight of the composition, the slag generally accounts for 20 to 50% by weight and preferably 30 to 40% by weight, and more preferably 35 to 40% by weight.

[0028] In addition to the slag, the cement-based composition of the present invention further comprises at least one hydraulic binder and / or at least one activator.

[0029] When present in the cement-based composition of the present invention, the hydraulic binder may advantageously comprise clinker, which may be selected from Portland clinker, aluminous clinker, sulfoaluminous clinker, ferro-aluminous clinker and mixtures thereof. Preferably, the hydraulic binder is selected from Portland cement, high alumina cement, sulfoaluminate cement, ferro-aluminate cement and mixtures thereof. The hydraulic binder comprising clinker is preferably selected from type I or type II Portland cement, i.e., CEM I or CEM 2 according to NF EN 197-1. In a preferred embodiment, the hydraulic binder may be used in an amount of less than or equal to 1% by weight relative to the total weight of the composition.

[0030] The term "calcium sulfoaluminate clinker" refers to a hydraulic material obtained by a method including heating a mixture at a high temperature (900 °C to 1450 °C), the mixture containing at least one source of lime (e.g., limestone with CaO varying between 50% and 60%), at least one source of alumina (e.g., bauxite, calcined alumina or other manufacturing by-products containing alumina) and at least one source of sulfate (gypsum, gypsum chemicals, natural or synthetic anhydrite, plaster, sulpho-calcic ashes). Preferably, the calcium sulfoaluminate clinker is characterized by a main calcium sulfoaluminate (yeelimit) phase (50% to 68% by weight relative to the total weight of the clinker) and a belite phase (10% to 20% by weight). The calcium sulfoaluminate clinker may also have other components such as ferrite, perovskite, mayenite, calcium ferroaluminate, etc., and the proportions of these other components vary from 0% to 20% by weight.

[0031] "Calcium ferroaluminate clinker" refers to a hydraulic material which is manufactured by firing a mixture of raw materials containing at least calcium oxide, alumina and ferrite in a furnace at a high temperature (1300 °C to 1600 °C).

[0032] "High-alumina clinker" refers to a material selected from the materials defined by the standard NF EN 14647 (fused high-alumina cement (CA) or calcium aluminate cement). These materials are produced by the melting of a mixture of limestone and bauxite, followed by grinding without gypsum to a fineness comparable to that of Portland cement.

[0033] Preferably, the cement clinker has a Blaine specific surface area of 3000 cm 2 / g to 6000 cm 2 / g. The Blaine specific surface area can be determined as described in paragraph 4 of EN 196-6.

[0034] The term "hydraulic binder" should be understood to refer to all hydraulic binders present in the composition collectively where appropriate.

[0035] Relative to the weight of the cement-based composition, the total content of the hydraulic binder and slag in the dry mortar is preferably in the range of 15% to 45% by weight, preferably in the range of 30% to 40% by weight.

[0036] Advantageously, the weight ratio of the hydraulic binder to the slag ranges from 5 g / kg to 50 g / kg, preferably from 7 g / kg to 30 g / kg, and more preferably from 20 g / kg to 30 g / kg.

[0037] The composition of the present invention may additionally comprise an activator, that is to say a system comprising at least one compound suitable for improving the setting and / or hardening of the slag. The activator may be selected from:

[0038] - basic activators, which include alkali metal hydroxides, alkaline earth metal hydroxides, alkali metal carbonates, alkali metal silicates, alkaline earth metal silicates and mixtures thereof, such as slaked lime, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium silicate, sodium metasilicate and / or potassium silicate,

[0039] - activators of the sulfate type, such as calcium sulfate and sources of calcium sulfate, such as gypsum, hemihydrate calcium sulfate, anhydrite and / or phosphogypsum.

[0040] Calcium sulfate is preferably used as an activator because it enables operation under mild conditions.

[0041] It is noted that the cementitious composition of the present invention may comprise one or more hydraulic binders, one or more activators or a mixture of both. In addition, the same material may act both as a hydraulic binder and as an activator, which is the case for lime. This is also true for Portland cement, which releases portlandite (Ca(OH) 2 ) during hydration and thus in-situ forms a calcium-based activator.

[0042] The content of the activator other than cement (especially Portland cement) and lime used in the composition of the present invention depends on the type of activator and may vary between 0.1% by weight and 15% by weight relative to the weight of the slag. This ensures satisfactory activation and water capture at the start of the reaction, while avoiding excessive late formation of ettringite and thus weakening the cementitious material after drying.

[0043] The cementitious composition of the present invention is characterized in that it further comprises biochar.

[0044] Biochar is a carbonaceous material remaining after biomass has been subjected to a heat treatment process in a low oxygen atmosphere, which results in carbonization. In some embodiments of the present disclosure, biochar refers to pyrolyzed biomass. The biochar used in the cementitious compositions of the present invention can be prepared using a fast pyrolysis (FP) process or a slow pyrolysis process (SP). Generally speaking, in the fast pyrolysis process, the feedstock is heated at a heating rate of 1 °C / second to 100 °C / second to a temperature of about 400 °C to about 900 °C for a period of several seconds to several tens of seconds, and the particle size used is usually less than about 6 mm. In contrast, in the slow pyrolysis process, the feedstock is slowly heated at a low heating rate (0.1 °C / second to 1 °C / second) to a temperature of about 300 °C to 500 °C for a period of several minutes, several hours or even several days, and the particle size or powder pile used usually has a particle size greater than about 0.6 mm, or more typically greater than about 1 cm.

[0045] Biomass wastes used for preparing biochar include, but are not limited to: agricultural residues (such as barley straw, rice husks, corn stover and bagasse) and food wastes; paper mill wastes; forestry and logging wastes; and animal manure. Other suitable biomass materials include, but are not limited to, energy crops such as switchgrass and sugarcane, bamboo, softwood (such as pine) and hardwood (such as poplar). One or more biomass materials or biochars can be used in the present invention. The feedstock material can be subjected to air classification to separate the biomass fraction with a high inorganic content from the main feedstock source to reduce its ash content. The feedstock material can also be size-reduced to form pellets or granules.

[0046] In a preferred embodiment, the biochar particles used in the present invention have a BET surface area of 150 to 400 m 2 / g, preferably 300 to 400 m 2 / g.

[0047] The cementitious composition of the present invention further comprises fine aggregate.

[0048] The aggregate used in the present invention has a diameter of less than 8 mm, which means that the cement-based composition does not contain aggregates with larger sizes. If the aggregate does not have a spherical shape, the "diameter" or "particle size" refers to the length of the larger dimension of the aggregate. More specifically, at least 90% by mass of the aggregate, preferably at least 95% by mass of the aggregate, has a particle size below 1.5 mm, such as a particle size of 0.1 to 1.5 mm, more preferably 0.1 to 1 mm, and still more preferably 0.1 to 0.5 mm, which can be measured by sieving. These aggregates are mineral particles, which include sand (based on silica and / or silica / limestone) and particles such as stones, limestone, quartz, dolomite, gravel, and / or pebbles. Their content generally varies between 30% by weight and 95% by weight, preferably 40% by weight and 70% by weight, and more preferably 50% by weight and 60% by weight, based on the weight of the cement-based composition.

[0049] The cement-based composition may further contain additives that impart specific properties to it. For example, reference will be made to rheology modifiers, water retention agents, air-entraining agents, thickeners such as cellulose ethers and starch ethers (in an amount of, for example, 0.2% to 0.7% by weight), biocidal protecting agents, dispersants, pigments, curing accelerators such as calcium formate (in an amount of, for example, 0.1% to 1% by weight) and / or setting retarders, wetting agents such as alkyl sulfonates (in an amount of, for example, 0.05% to 2% by weight), redispersible polymer powders (in an amount of, for example, 0.5% to 20% by weight), and mixtures thereof. The content of the additives may vary between 0.1% by weight and 10% by weight based on the total weight of the composition.

[0050] The redispersible polymer is a polymer that forms a latex or polymer dispersion once water is added to the cement-based composition. Examples include poly(vinyl esters of carboxylic acids), poly(alkyl methacrylates), vinyl aromatic polymers, polyolefins such as polyethylene, poly(vinyl halides), and mixtures thereof. 1 -C 15 The vinyl esters of carboxylic acids), poly(alkyl methacrylates), vinyl aromatic polymers, polyolefins such as polyethylene, poly(vinyl halides), and mixtures thereof. 1 -C 15 The vinyl esters of carboxylic acids), poly(alkyl methacrylates), vinyl aromatic polymers, polyolefins such as polyethylene, poly(vinyl halides), and mixtures thereof.

[0051] The cement-based composition may further contain low-density fillers such as expanded glass, expanded clay, vermiculite, and / or expanded perlite, which may be coated with a hydrophobic layer. Organic fillers such as expanded polystyrene and expanded elastomers can also be used for this purpose.

[0052] The present invention also relates to a method for preparing mortar, which includes mixing the cement-based composition with water, preferably in a weight ratio of water to the composition in the range of 20% to 40%, preferably 25% to 30%.

[0053] This mortar can be used to manufacture tile adhesives, such as adhesives for bonding ceramic or glass tiles or joints; assembling building components; as exterior wall mortar, such as rendering mortar, primer coat, single-coat base plaster, organic finish mortar, insulating mortar and waterproof mortar; or as repair mortar, such as injection mortar.

[0054] The mortar can be applied to any substrate, such as walls, panels or floors (such as a screed), so as to be covered with tiles. The tiles can be made of various materials, such as ceramics, sandstone, cement, stone, marble, etc. For example, the mortar can be applied to the substrate and can be applied to the tiles with a glue comb, trowel or notched trowel.

[0055] As measured according to the DIN EN ISO 17892-11:2019 standard, the hardened mortar usually has a water permeability coefficient of less than 0.1 cm / s and usually less than 0.05 cm / s. Description of the Drawings

[0056] Figure 1 Shows the comparison of the tensile strength of a tile adhesive prepared from a cement-based composition according to the invention and a tile adhesive without biochar under different conditions.

[0057] The present invention will be better understood with reference to the following examples, which are given for illustrative purposes only and are not intended to limit the scope of the present invention, the scope of which is defined by the appended claims.

[0058] Example

[0059] A dry mortar is prepared by blending the following components:

[0060] Component Quantity (wt%) Blast furnace slag 38％ Activator (including cement) and additive 3％ Biochar 2.7％ Redispersible polymer powder 3％ Aggregate and filler (including sand) 53.3％ Total 100％

[0061] Then the dry mortar is mixed with 28% (by weight of the dry mortar) of water at a temperature of 23 °C to obtain a tile adhesive, which is divided into samples. The mortar samples thus obtained are applied to the concrete surface and subjected to an adhesion test using standardized tiles according to NF EN 12004-2. The tensile strength is measured after 1, 7 and 28 days at 23 °C and after 29 days at 70 °C. Another set of samples is tested for their tensile strength when wet according to NF EN 12004-2. Finally, the tensile strength after 30 minutes of open time is measured according to NF EN 12004-2. Comparative samples are obtained from the same formulation as above, but with the biochar replaced by the corresponding amount of sand and prepared and tested in the same manner.

[0062] The results of these experiments are shown inFigure 1 It can be seen that the dry and wet tensile strengths of the samples according to the present invention are similar to those of the comparative samples, and they even increase slightly after a 30-minute open time.

[0063] In addition, a panel of five people evaluated the odor of the prepared mortar without biochar, which was stored overnight in a plastic bucket closed with a lid. After 24 hours, their odor was similar to that of rotten eggs. In contrast, the odor of the mortar according to the present invention was significantly reduced or even imperceptible to some people.

[0064] Finally, calculations were made to evaluate the CO 2 footprint of the above formulations according to the present invention, but compared to the formulations without biochar, this formulation contains 2.9% biochar instead of 2.7%. Emissions from transportation or preparation are not considered (only CO 2 emissions from the components of the formulation are considered). It was found that the CO 2 emissions of the formulation of the present invention are 0 kg CO 2 eq. / ton of product, while the CO 2 emissions of the comparative formulation are 90 kg CO 2 eq. / ton of product.

Claims

1. A cement-based composition, comprising: - slag, - at least one hydraulic binder and / or at least one activator, - biochar particles, and - aggregate, wherein the weight ratio of the biochar to the slag ranges from 0.025:1 to 0.15:1, characterized in that the composition is a dry mortar, and the aggregate has a diameter of less than 8 mm and comprises sand.

2. The cement-based composition according to claim 1, characterized in that the hydraulic binder comprises ground clinker selected from Portland clinker, high-alumina clinker, sulphoaluminate clinker, ferroaluminate clinker and mixtures thereof, preferably the hydraulic binder is selected from Portland cement, high-alumina cement, sulphoaluminate cement, ferroaluminate cement and mixtures thereof.

3. The cement-based composition according to claim 2, characterized in that the weight ratio of the hydraulic binder to the slag ranges from 5 g / kg to 50 g / kg, preferably from 7 g / kg to 30 g / kg, and more preferably from 20 g / kg to 30 g / kg.

4. The cement-based composition according to any one of claims 1 to 3, characterized in that it comprises at least one activator selected from the group consisting of: - alkaline activators, which include alkali metal hydroxides, alkaline earth metal hydroxides, alkali metal carbonates, alkali metal silicates, alkaline earth metal silicates and mixtures thereof, such as slaked lime, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium silicate, sodium metasilicate and / or potassium silicate, - activators of the sulphate type, such as calcium sulphate and sources of calcium sulphate, such as gypsum, hemihydrate calcium sulphate, anhydrite and / or phosphogypsum.

5. The cement-based composition according to claim 4, characterized in that the activator accounts for 0.1 to 15% by weight of the weight of the slag.

6. The cement-based composition according to any one of claims 1 to 5, characterized in that the slag is selected from slags produced by metallurgical processes, such as blast furnace slag, oxygen steel furnace slag, electric furnace slag and mixtures thereof, preferably the slag is blast furnace slag.

7. The cement-based composition according to any one of claims 1 to 6, characterized in that relative to the total weight of the composition, the slag accounts for 20% to 50% by weight, preferably 30% to 40% by weight, and more preferably 35% to 40% by weight.

8. The cement-based composition according to any one of claims 1 to 7, characterized in that The biochar particles have a BET surface area of 150 to 400 m 2 / g, preferably 300 to 400 m 2 / g.

9. The cement-based composition according to any one of claims 1 to 8, characterized in that the aggregate has a particle size of 0.1 to 1.5 mm, more preferably 0.1 to 1 mm, and even more preferably 0.1 to 0.5 mm.

10. A mortar prepared by combining the cement-based composition according to any one of claims 1 to 9 with water, preferably the weight ratio of water to the cement-based composition ranges from 20% to 40%, preferably from 25% to 30%.

11. A method for preparing mortar, which comprises mixing a cement-based composition according to any one of claims 1 to 9 with water, preferably the weight ratio of water to the composition ranges from 20% to 40%, preferably from 25% to 30%.

12. Use of the mortar according to claim 10, the use of the mortar being for manufacturing tile adhesives, such as adhesives for bonding ceramic or glass tiles or joints; assembling building components, such as masonry mortar; as exterior wall mortar, such as rendering mortar, primer coat, single-coat base coat, interior wall plaster, organic finish mortar, insulating mortar and waterproof mortar; as floor mortar; or as repair mortar, such as injection mortar.

13. Use of biochar to reduce the odor of slag in a mortar composition.

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