1241 results about "Pulverised fuel ash" patented technology

The invention discloses solid-waste-based fluid-state solidified soil and a preparation method thereof, and belongs to the technical field of solid waste resource utilization. Raw soil is used as a base material, a curing agent composed of steel slag, granulated blast-furnace slag, gypsum, fly ash, aluminate and other industrial solid waste, a flocculating agent, a conditioning agent, a modifying agent, a stabilizing agent and a soil modifying agent are doped, and then the solid-waste-based fluid-state solidified soil is prepared. Adding water and stirring to form premixed flow-state solidified soil; comprising dry powder and water, and the mass ratio of the water to the dry powder is 0.65-0.75; the dry powder comprises the following components in parts by mass: 80-85 parts of raw soil, 10-15 parts of a curing agent, 2-5 parts of a flocculating agent, 0.5-1.5 parts of a conditioning agent, 1-3 parts of a modifying agent, 0.2-0.4 part of a stabilizing agent and 3-5 parts of a soil modifying agent. The solid-waste-based fluid-state solidified soil prepared by the method has the characteristics of high fluidity, high strength, relatively good water stability, low cost and the like, is beneficial to actual production, and conforms to a green development mode.

The invention discloses crack-chloride ion double-triggered subsea tunnel corrosion-resistant concrete and a preparation method thereof, and relates to the field of subsea tunnel engineering materials. The concrete is prepared from the following components in parts by weight: 400 to 500 parts of Portland cement, 50 to 80 parts of fly ash, 60 to 100 parts of superfine mineral powder, 1000 to 1100 parts of coarse aggregate, 700 to 800 parts of fine aggregate, 140 to 160 parts of water, 10 to 20 parts of self-repairing microcapsules and 1 to 5 parts of a water reducing agent, the self-repairing microcapsule comprises a capsule wall material, a self-repairing material and a layered dihydroxyl composite metal oxide. A crack-chloride ion double-response system is constructed, and the limitation of traditional single trigger repair is broken through. When a crack with a certain width appears in the concrete, the capsule wall of the self-repairing microcapsule is broken to release the repairing component, so that effective filling of the crack is realized; and meanwhile, the layered double-metal hydroxide can directionally adsorb chloride ions to form a stable compound, so that the migration rate of the chloride ions is remarkably reduced.

The invention discloses low-shrinkage all-solid waste concrete and a preparation method thereof. The low-shrinkage all-solid waste concrete is prepared from the following raw materials in parts by mass: 14 to 20 parts of solid waste-based cementing material, 25 to 40 parts of high-titanium heavy slag sand, 35 to 50 parts of high-titanium heavy slag gravel, 5.5 to 7.5 parts of water and 0.2 to 0.5 part of water reducing agent, the solid waste-based cementing material comprises the following components in parts by mass: 40-70 parts of water-quenched slag powder, 10-30 parts of carbide slag, 10-20 parts of gypsum, 5-20 parts of fly ash and 0-5 parts of silica fume. By utilizing the internal curing effect of the titanium slag aggregate, continuous water can be provided for concrete hydration, the later-stage dry shrinkage of the concrete is reduced, and the strength of the concrete is improved; the high alkalinity of the carbide slag and the high sulfate content of the gypsum are utilized, and the alkali-sulfate synergistic excitation effect is utilized, so that the activity of the water-quenched slag powder and the like can be fully excited under the condition that cement and a chemical exciting agent are not used, and the strength performance of the concrete is ensured; meanwhile, steel slag is not used as a component material, so that the problem of poor concrete volume stability caused by the steel slag can be avoided.

The invention relates to a high-performance solid-waste-based offshore wind power grouting material and a preparation method thereof, and a solid-waste-based cementing material is a hydraulic cementing material prepared by processing and grinding one or more solid wastes such as water-quenched blast furnace slag, steel slag, desulfurized gypsum, fly ash, red mud, tailings, carbide slag and phosphogypsum as raw materials according to a certain proportion. The solid waste-based cementing material is adopted to replace 525 Portland cement, the prepared grouting material product is excellent in performance, the carbon emission of the grouting material product is remarkably reduced, the cost is also reduced, resource utilization of industrial solid waste is facilitated, meanwhile, the performance of the grouting material is obviously improved, and the grouting material is suitable for popularization and application. The advantages of ultrahigh strength, elasticity modulus, high flowability, low shrinkage and high durability are realized.

Disclosed are a filling curing agent for preparing mine superfine tailing slag from solid waste residues, which belongs to the field of preparation of solid waste residues. The filling curing agent comprises a cementing material component obtained by means of a wet milling process while grinding, and an exciting agent component obtained by means of a mixing and stirring process; the cementing material component comprises, in parts by mass, 45-50 parts of blast furnace slag powder, 35-40 parts of steel slag powder, 15-20 parts of coal ash and 53.8 parts of water, and the exciting agent component comprises 100 parts of desulfurized gypsum powder and 59.5-60.6 parts of an activating agent; and the weight of the exciting agent component accounts for 10-15% of the weight of the filling curing agent. The filling curing agent disclosed in the present invention has low filling cost, high filling body strength and good durability, which reduces the occupation of land resources, reduces the impact on the ecological environment and residents' lives, realizes a virtuous cycle of mining and filling, and has good industrial prospects and social benefits.

The present invention belongs to the field of resource utilization of building materials and solid waste, and relates to a red-mud-based cementing material based on efficient drying, component homogenization and activity improvement, and a preparation method therefor. The preparation method comprises: adding a filter aid to red mud to carry out sedimentation, then subjecting same to filter pressing until the water content is 14-16%, then drying the solid material, which has been subjected to filter pressing, until the water content is 4% or below, and finally grinding same to obtain the product. The filter aid comprises the following raw materials: 10-30 parts of polyaluminum chloride, 5-15 parts of polyaluminum sulfate, 1000-1200 parts of blast furnace slag or fly ash, 700-900 parts of steel slag, 400-600 parts of carbide slag or alkaline residues, and 300-400 parts of desulfurized gypsum or phosphogypsum or fluorgypsum. By means of the present invention, the dehydration efficiency of red mud can be improved, the red-mud-based cementing material can also be prepared in one step; the preparation process for the red-mud-based cementing material is simplified; and the prepared red-mud-based cementing material has the advantages of a high mechanical strength, high durability and erosion resistance.

The invention relates to a high-strength stable solid waste-based composite cementing material and a preparation method and application thereof in the field of building materials. The high-strength stable solid waste-based composite cementing material is prepared from the following raw materials in parts by weight: 70-85 parts of composite solid waste micro powder; 10 to 20 parts of Portland cement clinker; 3-8 parts of a composite activator; 0.5 to 2 parts of a nano-scale function regulator; wherein the composite solid waste micro powder is prepared by mixing and grinding the following raw materials in parts by weight: 40-60 parts of blast furnace slag powder; 20 to 30 parts of fly ash; 10-20 parts of chemically modified electrolytic manganese residue powder; and 5-15 parts of steel slag powder. According to the preparation method, sodium metasilicate is adopted to assist medium-temperature calcination to chemically modify the electrolytic manganese residues, so that not only is the gelation activity of the electrolytic manganese residues effectively excited, but also free-state manganese, cadmium and other heavy metal ions in the electrolytic manganese residues are fixed in situ in newly formed zeolite-like silicate mineral lattices through thermochemical reconstruction; and a brand new technical path is opened up for safe and high-value utilization of the typical hazardous waste, namely the electrolytic manganese residues.

The invention discloses a cementing material for a solid waste-based road of a coal-fired power plant and a preparation method of the cementing material. The cementing material mainly comprises a cementing component, an alkali-activated component and a reinforcing component, the gelling component is a mixture of coal-fired power plant fly ash and furnace slag; the alkali-activated component is a mixture of alkali residues, red mud, blast furnace slag and coal-fired power plant desulfurized gypsum; the reinforcing component is rice hull ash or peanut hull ash. The mass ratio of the gelling component to the alkali-activated component is (4 / 1)-(10 / 1); and the addition amount of the reinforcing component is 1-3% of that of the main body material. The coal-fired power plant solid waste fly ash, the furnace slag and the desulfurized gypsum are used as main bodies, a small amount of other industrial solid waste is added, and the cementing material belongs to a full-solid-waste low-carbon cementing material and can be applied to a road base, a subbase or a base layer. The invention has the characteristics of low carbon emission, high solid waste consumption, simple production process and strong pavement performance, and in addition, the invention has a good stabilization effect on the problem that part of solid waste heavy metals and sulfate ions in a coal-fired power plant exceed the standard.

The invention provides an early-strength rapid-repair grouting material and a preparation method thereof, and the early-strength rapid-repair grouting material is mainly prepared from the following raw materials: 50 to 150 parts of sulphoaluminate cement, 10 to 150 parts of aluminate cement, 200 to 350 parts of a regenerated gelling powder material, 1200 to 1400 parts of quartz sand, 50 to 100 parts of silica fume, 10 to 150 parts of mineral powder, 10 to 100 parts of fly ash, 15 to 50 parts of a composite retarder, 0.1 to 2 parts of a water reducing agent and 1 to 10 parts of an early strength agent. 0.01 to 1 part of a water-retaining agent and 200 to 300 parts of water. The early-strength quick-repair grouting material is characterized in that activated low-cementitious active mineral solid waste is adopted as a main cementitious material, and the product has excellent construction stability, low-carbon weather resistance, corrosion resistance, micro-expansion quick-hardening early strength and economical efficiency.

The invention provides fly ash unfired ceramsite and a preparation method thereof. The fly ash unfired ceramsite is prepared by the following steps: granulating to obtain a ceramsite matrix, then carrying out secondary pelletizing to construct a shell structure, and carrying out composite curing. The ceramsite matrix is prepared from fly ash, cement, gypsum, an alkali activator and water; the shell is made of coal ash and cement. According to the invention, the problems of few reaction products and low strength of the fly ash unfired ceramsite caused by insufficient activity of fly ash are solved, and the technical problem of low granulation efficiency of the fly ash unfired ceramsite caused by difficulty in accurate control of a traditional water adding mode for granulation is solved. In addition, the problems of poor initial structural stability and durability of conventional unfired ceramsite are solved, so that the problem that when the fly ash unfired ceramsite is applied to the field of concrete, the mechanical property of the fly ash unfired ceramsite is weak is solved.

The invention discloses early-strength nano C-S-H crystal nucleus concrete in a low-temperature curing environment and a preparation method thereof. The concrete is composed of the following substances in parts by weight: 260-300 parts of PO52.5 ordinary Portland cement; 135 to 155 parts of slag; 60 to 70 parts of fly ash; the water-binder ratio is 0.27 to 0.31; the sand ratio is 0.40 to 0.44; the water reducing agent accounts for 1% of the mass of the gel body; the nano C-S-H crystal nucleus accounts for 6%-10% of the mass of the gel body; 1080 to 1210 parts of coarse aggregate; and 770 to 870 parts of fine aggregate. The method comprises the following steps: (1) respectively weighing the cement, the slag and the fly ash according to the parts by weight, putting into a stirrer, and stirring for 1 minute; 2) continuously adding sand and stone into the concrete mixer, and continuously stirring for about 2 minutes; and 3) adding the water, the water reducing agent and the nano C-S-H crystal nucleus into the mixture, and uniformly stirring for 2 minutes. The method effectively solves the problem of slow development of concrete strength in a low-temperature environment, also solves the problems of long construction period and high maintenance cost of a concrete structure in winter, and has obvious engineering significance and relatively strong economic benefits.

The invention belongs to the technical field of tunnel construction, and discloses SAP geopolymer sprayed concrete and application thereof in primary lining of a high-ground-temperature tunnel. The concrete is prepared from the following raw materials in parts by mass: 100 parts of a cementing material, 13-16 parts of an alkali activator, 135-150 parts of river sand, 165-185 parts of stones, 32-41 parts of water and a proper amount of SAP, in percentage by mass, the use amount of the SAP is 0.2-0.3% of the binding material; the cementing material is composed of slag and fly ash according to a mass ratio of (0.24-0.26): 1. The SAP geopolymer sprayed concrete is applied to primary lining of a high-ground-temperature tunnel. The SAP geopolymer shotcrete not only has high strength and high toughness of traditional shotcrete, but also has good heat insulation and heat resistance, has supporting and heat insulation performance, realizes environment-friendly and pollution-free construction, and is particularly suitable for high-ground-temperature tunnels and the like.

The invention provides low-carbon premixed concrete based on industrial solid waste synergistic activation and a preparation method of the low-carbon premixed concrete. The low-carbon premixed concrete is prepared from the following components: a nano silicon-based anti-corrosion early strength agent, a cementing material, recycled aggregate, electric furnace tailings, waste carbon fibers, a polycarboxylate superplasticizer and water, the preparation method comprises the following steps: S1, preparing a nano silicon-based anti-corrosion early strength agent through silane hydrolysis and modification reaction of nano silicon dioxide; s2, preparing a cementing material: mixing fly ash, steel slag, mineral slag and Portland cement, calcining, grinding, spraying a composite alkali activator, and aging; s3, mixing and forming: wet-mixing the cementing material, the recycled aggregate, the iron tailing sand, the waste fibrilia, the nano silicon-based anti-corrosion early strength agent, the polycarboxylate superplasticizer and water, and pre-injecting and forming; and S4, carbonization curing. According to the invention, efficient utilization of industrial solid waste is realized, and the low-carbon environmental protection performance and mechanical property of the concrete are improved.

The invention relates to the technical field of mine solid waste treatment and carbon dioxide sealing and storage, and particularly discloses a system and a method for sealing and storing carbon dioxide by utilizing coal-based solid waste and mine water to prepare slurry. The system comprises a cement bin, a gangue bin, a coal ash bin, a gasified slag bin, a mine water storage tank, a stirring reaction kettle, a carbon dioxide storage tank, a slurry temporary storage tank, a vacuum pump and a slurry pump, and the stability and adsorption efficiency of carbon dioxide fixation are improved in the mode that coal-based solid waste, mine water and carbon dioxide are subjected to chemical reaction and physical adsorption; meanwhile, the prepared backfill slurry has high-strength anti-pressure ability, the stability of the backfilled underground goaf is better improved, further, coal-based solid waste and mine water are utilized for waste recycling, and the carbon dioxide storage cost is reduced.

The invention discloses a road cementing material based on bulk solid wastes and a preparation method thereof, and belongs to the field of geopolymer cementing materials. The material is prepared from 35-38 parts of fly ash, 15-18 parts of acid-washed red mud, 22-25 parts of carbide slag, 20-23 parts of phosphogypsum, 5-8 parts of rice hull ash, 6-9 parts of a water reducing agent and water, and the water-binder ratio is (0.4-0.5): 1. Wherein the pickling red mud is treated by 5-6% dilute sulphuric acid (pH is 8-9, and heavy metal is reduced by 30%), and the rice hull ash (SiO2 is greater than or equal to 85%) and the nano silicon dioxide (10-30nm) synergistically optimize the microstructure. The 28-day compressive strength of the material is larger than or equal to 35 MPa, the load cycle strength loss rate is smaller than or equal to 5%, the CO2 emission amount is 62 kg / t, the heavy metal leaching concentration is lower than the national standard by 50%, and the cost is only 31.6% of that of traditional cement. According to the invention, efficient synergistic utilization of four solid wastes of fly ash, red mud, carbide slag and ardealite is realized, and the concrete has the characteristics of high strength, low pollution, salt corrosion resistance and the like, is suitable for heavy-duty road base and severe cold area engineering, and has remarkable environmental protection and economic values.

The invention provides a CO2 mineralized cementing material based on steel slag-mineral slag-fly ash multi-element solid waste and a preparation method, and relates to the technical field of building materials. The CO2 mineralized cementing material based on the steel slag-slag-fly ash multi-element solid waste is prepared from the following raw materials in parts by mass: 10 to 15 parts of steel slag, 30 to 40 parts of slag, 50 to 60 parts of slag fly ash, 5 to 20 parts of gypsum, 1 to 5 parts of clinker, 1 to 5 parts of cement, 5 to 20 parts of exciting agent, 4 to 6 parts of cross-linking agent composition, 0.1 to 0.5 part of alkaline water and 0.1 to 0.5 part of defoaming agent. According to the invention, the steel slag, the furnace slag and the furnace slag fly ash are excited by adopting a composite exciting agent of aluminum sulfate, calcium aluminate and sodium hydroxide, the problem of early strength is successfully solved through alkali excitation and aluminate excitation, the proportion of the exciting agent is reasonably configured, the effect of the exciting agent is exerted to the maximum extent, and the mechanical strength of the CO2 mineralized cementing material is improved.

The invention belongs to the technical field of filling of an aluminum goaf under coal, and particularly relates to a bag type filling synergistic mineralization carbon dioxide sequestration method for mining a red mud-based filling material based on an aluminum strip under coal. Comprising the following steps that S1, filling bags are arranged; s2, grouting the aluminum layer bottom plate; s3, CO2 is conveyed; s4, red mud slurry is injected; s5, grouting between coal and aluminum layers; according to the method, through aluminum layer bottom plate grouting and coal aluminum interlayer grouting, Ordovician limestone water is effectively prevented from protruding out, harmful substances are effectively prevented from permeating underground water, meanwhile, a sealing cover layer for CO2 injection is also used, and the mineralization amount of CO2 is effectively increased. The main components of the red mud slurry are red mud, fly ash and crushed coal gangue, solid waste accumulation and environmental pollution are effectively reduced while the filling cost is remarkably reduced, recycling is achieved, the red mud is sealed in a flexible filling bag in a goaf, and if necessary, valuable elements in the red mud can be used for filling the goaf. And the tea leaves can also be extracted.

The invention relates to the technical field of building construction materials, in particular to low-carbon high-performance concrete and a preparation method thereof. The low-carbon high-performance concrete is prepared from the following preparation raw materials in parts by mass: 150 to 180 parts of Portland cement, 24 to 27 parts of sulphoaluminate cement, 120 to 150 parts of activated coal gangue powder, 60 to 80 parts of fly ash, 600 to 700 parts of gravel, 60 to 65 parts of modified basalt fiber, 20 to 25 parts of limestone powder, 10 to 12 parts of light calcined magnesia, 2 to 3 parts of accelerant, 7 to 10 parts of modified polycarboxylate superplasticizer and 180 to 220 parts of water. According to the low-carbon high-performance concrete disclosed by the invention, excellent mechanical properties and durability are ensured, the environmental protection targets of low cost and low carbon emission are achieved, and a new solution is provided for sustainable development of concrete materials.

The invention discloses a CO2 inflation foaming preparation method of a ternary solid waste foam cement thermal insulation material, which comprises the following steps: step 1, weighing desulfurized gypsum, fly ash, mineral powder and an additive, and uniformly stirring for later use; step 2, weighing water with required weight, and uniformly stirring the uniformly mixed dry material and water to form uniform slurry; step 3, stirring the uniform slurry at a high speed, and filling CO2 gas while stirring, so as to prepare inflatable foaming slurry; step 4, pouring the inflatable foaming slurry into a mold, weighing a sample, loading the sample into a self-sealing bag, sealing, and curing in a natural environment; and step 5, after curing to the age, taking out the sample, and drying to constant weight to prepare the ternary solid waste foam cement thermal insulation material. The ternary solid waste foamed cement thermal insulation material which takes CO2 as foaming gas, the desulfurized gypsum as a main cementing material and the fly ash and the mineral powder as auxiliary cementing materials is prepared, and meets the A08 grade requirement specified by the standard of foam concrete.

The invention discloses a preparation method of a prefabricated autoclaved aerated concrete slab made of a solid-waste-based sulfur-aluminum-iron binding material. The preparation method comprises the following steps: preparing dry substances of the material; carrying out solid waste pretreatment by a mechanical ball milling method; adding ardealite, aluminum ash, coal gangue, fly ash, steel slag and carbide slag at the moment; calcining and directionally mineralizing after pretreatment; secondarily grinding the intermediate material; adding the secondarily ground intermediate material, cement, aluminum powder and water, and foaming; after the slurry is thickened, multi-frequency vibration is carried out in the pouring process; after pouring is completed, multi-temperature curing is conducted; after curing is completed, the highly-doped solid waste-based functional prefabricated autoclaved aerated concrete slab product is obtained. According to the autoclaved aerated concrete slab, dependence on natural resources is effectively reduced, meanwhile, carbon dioxide emission in the production process is reduced, and meanwhile, the compressive strength and the breaking strength of the autoclaved aerated concrete slab are improved; the service life of the material is prolonged; the preparation process is simplified, and the production difficulty and cost are reduced.

The invention discloses multi-scale toughened full-solid-waste ultrahigh-ductility concrete, which is prepared from the following raw materials in parts by weight: 500 to 650 parts of full-solid-waste cementing materials, 110 to 150 parts of calcined coal gasification slag, 190 to 250 parts of calcined fly ash, 20 to 40 parts of silica fume, 10 to 30 parts of metakaolin, 780 to 930 parts of washed sand, 10 to 25 parts of fly ash fibers, 0.6 to 0.9 part of hydroxypropyl methyl cellulose, 20 to 30 parts of polycarboxylic acid water reducing agents and 300 to 400 parts of water. The calcined coal gasification slag is subjected to gradient heating to 800-960 DEG C, heat preservation is conducted for 30-60 min, then the calcined coal gasification slag is cooled to the room temperature at the cooling rate of 10-15 DEG C / min, and the calcined coal gasification slag is obtained after powder grinding. According to the multi-scale toughened full-solid-waste ultrahigh-ductility concrete provided by the invention, the toughness and the mechanical property of the concrete can be enhanced, the performance of the concrete in an extreme environment is improved, meanwhile, the solid waste utilization rate is increased, and the production cost of the concrete is reduced.

The invention relates to a method for improving early-stage performance of an all-solid-waste cementing material, and aims to improve the early-stage performance of the cementing material. At present, the early strength (1d strength) of an all-solid waste cementing material is generally low, but the characteristic is closely related to construction efficiency and is a key limit for large-scale application of the all-solid waste cementing material. Sintering is not included in the working procedures, and the product does not contain cement clinker. The method comprises the following steps: selecting industrial solid wastes such as steel slag, blast furnace water slag, iron alloy slag, silicomanganese slag, industrial byproduct gypsum, sintering fly ash, fly ash, calcined coal gangue and the like as raw materials; the industrial solid waste is subjected to independent or mixed grinding treatment; by optimizing the raw material ratio and introducing key component minerals, the specific surface area of the cementing material is increased, and active sites of the key minerals are dissociated and exposed. The mass of the introduced key components for optimizing the raw material ratio accounts for less than or equal to 15% of the total mass of the cementing material, the mass fraction of the key and active minerals is increased by less than or equal to 10%, and the early strength of the all-solid waste cementing material is increased by 30%.

The invention discloses a method for preparing all-solid-waste-based non-sintered ceramsite through solid waste synergetic recycling. Dechlorinated household garbage incineration fly ash is combined with various solid wastes; 20-45 parts of thermal power plant fly ash, 35-55 parts of blast furnace granulated slag, 5-15 parts of flue gas desulfurization gypsum and 5-15 parts of water-washed and dechlorinated household garbage incineration fly ash are weighed, prepared and mixed according to a proportioning scheme; after uniformly stirring, adding pure water accounting for 35 + / -0.5% of the dry weight of the powder, and stirring to obtain alkali-activated gelling slurry; the ceramsite with the weight of about 3.5 g + / -0.1 g is prepared and naturally cured for several days under the condition of room temperature. The specific alkali-activated gelling slurry is reasonably calculated and deduced, so that in the ceramsite preparation process, no additive is added, only 7 days of natural curing at room temperature are needed, the excellent characteristics of high strength, low cost, easy preparation, no energy consumption and no carbon emission can be achieved, and the purpose of environmental protection is really achieved.

The invention provides solid-waste-based cementing material coal gangue vegetation concrete and a preparation method thereof. The solid-waste-based cementing material coal gangue vegetation concrete is prepared from the following raw materials: coal gangue aggregate, a solid-waste-based cementing material, tap water, water glass, KNO3 and polyvinyl alcohol building rubber powder. The coal gangue aggregate is used as a structural framework, the coal gangue powder, the mineral powder and the fly ash are used as cementing materials, and the low-alkali equivalent water glass is used as an alkali component, so that the strength requirement is met, and the pH is reduced. A proper amount of KNO3 and polyvinyl alcohol building rubber powder are doped, so that the workability of the slurry is improved, and meanwhile, the slurry has relatively high water permeability and mechanical property. According to the coal gangue vegetation concrete, solid waste materials can be fully utilized, particularly, coal gangue can be efficiently utilized, and the vegetation performance requirements can be met through a high-porosity different-aperture gradient permeation structure and low alkalinity of the coal gangue vegetation concrete. The method is suitable for greening laying of road slopes, river channel protection slopes, squares and parking lots and mine slopes, the slope surfaces can be reinforced, water and soil loss can be prevented, air can be purified, the ecological environment of a mining area can be repaired, and ecological balance can be maintained.

The invention provides a preparation method of a multi-source coal-based solid waste filling material, and belongs to the technical field of solid waste reutilization, and the preparation method comprises the following steps: uniformly mixing cement, fly ash, furnace bottom slag, desulfurized gypsum, coal gangue, gasified slag and a water reducing agent to obtain a mixed material; and adding fluorine-containing mine water into the mixed material, stirring and mixing to obtain the cemented multi-source coal-based solid waste filling material with predetermined fluidity and bleeding rate. The invention further provides application of the multi-source coal-based solid waste filling material. According to the preparation method and application of the multi-source coal-based solid waste filling material, the coal-based solid waste can be comprehensively recycled and is environmentally friendly, and the prepared multi-source coal-based solid waste filling material can effectively control and treat fluorine ions in mine water.

The invention discloses a composite system geopolymer grouting material and a preparation method thereof. The composite system geopolymer grouting material comprises the following raw materials in percentage by mass: 50-70% of coal gangue, 10-30% of fly ash and 10-30% of cement. Functional additives: 5%-20% of desulfurized gypsum and 5%-15% of bentonite; the composite exciting agent is formed by compounding carbide slag and sodium silicate according to the mass ratio of 1: 1-1: 2. The geopolymer is excellent in mechanical property, meets engineering requirements, is remarkable in environmental protection benefit, conforms to double-carbon target low-carbon process innovation: a calcination-free process: traditional high-temperature calcination is abandoned (the temperature needs to be 550-900 DEG C), carbon emission is reduced by more than 30% (compared with a contrast, the carbon emission of a traditional process is increased by 35%), and the geopolymer conforms to the green positioning of low energy consumption and low three wastes of geopolymers. The cost advantage is prominent, the economic value is remarkable, the raw material cost is reduced, specifically, the coal gangue (low-cost solid waste) is used for replacing 30%-50% of cement, and the comprehensive raw material cost is reduced by 40% (compared with a traditional cement-based grouting material).

The invention belongs to the technical field of agricultural biology and soil remediation, and particularly relates to a mining area soil remediation method. The method comprises the following steps: performing soil reconstruction on a mining area to obtain reconstructed soil with a multi-layer structure; the reconstructed soil of the multi-layer structure sequentially comprises a reconstruction layer, a blocking layer and a filling layer from top to bottom. The reconstruction layer comprises low-carbon coal gangue and surface soil, the particle size of the low-carbon coal gangue is smaller than or equal to 8 mm, and the mass ratio of the low-carbon coal gangue to the surface soil is (1-2): (1-2); the blocking layer comprises a grouting mixture of fly ash and cement, and the mass ratio of the fly ash to the cement is smaller than or equal to 1.8: 1; the filling layer comprises blocky waste coal gangue; and then planting alfalfa on the reconstructed soil with the multilayer structure. According to the method, recycling of the waste coal gangue and reconstruction of the mining area soil are realized, so that smooth germination and healthy growth of alfalfa seeds on the reconstructed soil are ensured, mining area soil remediation is realized, and an economical and feasible method is provided for mining area soil remediation.

The invention discloses concrete suitable for a high-altitude large-temperature-difference environment, and belongs to the technical field of building materials. In order to solve the problems of insufficient durability and easy cracking of traditional concrete in high altitude areas due to large day and night temperature difference, the technical scheme provided by the invention is as follows: a cementing material is a composite system composed of Portland cement, fly ash and slag powder, is matched with 5-20mm continuous grading coarse aggregate and river sand with fineness modulus of 2.3-2.8, and is added with basalt fiber and polypropylene fiber; and an air entraining agent, a polycarboxylate superplasticizer and water. The concrete has excellent crack resistance, freezing and thawing resistance and thermal stability by optimizing aggregate gradation, introducing multi-scale fiber for reinforcement, regulating and controlling the hydration heat of a cementing material and matching with an additive in a specific proportion to improve the working performance. The concrete is suitable for engineering such as plateau bridges and tunnels, the service life of the structure can be remarkably prolonged, and the maintenance cost is reduced.

The invention discloses coal-based solid waste negative carbon filling slurry for an underground goaf and a preparation method of the coal-based solid waste negative carbon filling slurry. The coal-based solid waste negative carbon filling slurry is prepared from the following components in percentage by mass: 60-65% of coal gangue, 18-22% of fly ash, 9-12% of a carbon sequestration material, 5-9% of cement, 0.5-1.5% of water glass and 0.1-0.5% of an alkali activator. The carbon sequestration amount and compressive strength of the material are improved by adjusting the water cement ratio, the solid waste ratio and the additive ratio, the prepared slurry has certain fluidity and can be conveyed to a mine pit goaf through a pipeline, the carbon sequestration amount of the slurry reaches up to 65.6 kg CO2 / t coal-based solid waste, the compressive strength of a test piece reaches up to 5.6 MPa after the slurry is solidified, and the strength requirement of the mine pit backfill material can be met. The preparation method is low in cost, and the prepared slurry does not pollute underground water resources, is green and environment-friendly, and has a remarkable carbon sequestration effect.

The invention provides a multi-solid-waste cementing material as well as a preparation method and an application method thereof. The multi-solid-waste cementing material comprises a multi-solid-waste cementing material and engineering residue soil, wherein the multi-solid-waste cementing material comprises 25%-35% (by mass) of superfine slag powder, 25%-35% (by mass) of fly ash, 7%-15% (by mass) of coal gangue, 8%-15% (by mass) of carbide slag, 5%-12% (by mass) of superfine steel slag powder and 8%-14% (by mass) of an alkali activator; the mass ratio of the multi-solid waste cementing material to the engineering residue soil is 1: (6-8). The cementing material is prepared from a plurality of industrial solid wastes, and has the characteristics of high backfill strength, good fluidity, difficulty in shrinkage, low carbon and environmental protection.