56 results about "Calcium ferrite" patented technology

The invention discloses a method for preparing composite calcium ferrite from phosphogypsum and calcium-process vanadium extraction tailings, and belongs to the technical field of metallurgy. The invention relates to a method for preparing composite calcium ferrite from ardealite and calcium-process vanadium extraction tailings. The method comprises the following steps: drying the ardealite and the calcium-process vanadium extraction tailings; uniformly mixing and grinding the dried material and carbon-containing reducing agent powder to obtain a mixed and ground material; adding water into the mixed and ground material, pressing the mixed and ground material into material ball blocks, and drying the material ball blocks under preset conditions; placing the dried material ball block in a reactor for calcining, and cooling to obtain a sample which is composite calcium ferrite in the reaction container; according to the method, sulfur in the ardealite and the vanadium extraction tailings is removed in the form of sulfur dioxide at high temperature through external carbon, the removal rate of sulfur reaches 95% or above, calcium ferrite with the effective content being 50% or above and a small part of sulfur dioxide flue gas in the prepared composite calcium ferrite are prepared, and calcium, sulfur and iron resources in the ardealite and the vanadium extraction tailings can be fully recycled.

The invention discloses an ardealite resource comprehensive utilization method and application thereof, and belongs to the technical field of ardealite resource utilization. The method comprises the following steps: S1, mixing ardealite and a reducing agent to obtain a mixture; s2, performing high-temperature decomposition treatment on the mixture in an inert atmosphere to obtain decomposed gas and a decomposed product; s3, sulfuric acid and / or carbon disulfide are / is prepared with the decomposition gas as the raw material, and the decomposition product is used for metallurgical steelmaking; according to the method, ferrous sulfide is used as a reducing agent, under the inert atmosphere, phosphogypsum is reduced into calcium oxide and calcium ferrite, generated sulfur dioxide tail gas is recycled, and comprehensive utilization of calcium and sulfur resources of phosphogypsum solid waste is achieved; the recycled sulfur dioxide can be used for preparing sulfuric acid and / or carbon disulfide, meanwhile, calcium oxide and calcium ferrite can serve as an adhesive and a slag former to be used for efficient metallurgical steelmaking, and the comprehensive utilization method for ardealite resources has a good application prospect.

According to the system and the control method for improving the sinter quality of the sintering machine, the oxygen concentration in ignition combustion-supporting gas is actively and intelligently adjusted, and traditional passive adaptation is converted into active precise adjustment and control. And the mixing flow of the oxygen-enriched gas is dynamically adjusted according to monitored real-time data, so that the constant optimal ignition intensity is maintained. And then an optimized ignition system matched with oxygen-enriched ignition is designed, and generation of high-strength binding phase calcium ferrite is facilitated. And finally, through safety interlocking, when combustion-supporting air is abnormal, the oxygen content is too high and no coal gas is supplied, an oxygen-enriched pipeline stop valve needs to be closed, so that the system safety is guaranteed. The ignition uniformity and stability are improved, the ore return rate is effectively reduced, and a virtuous cycle is formed.

The present invention relates to the technical field of building materials, and discloses a seawater-resistant calcium ferrite cement concrete and a preparation method thereof, which are obtained by using bis[3-(trimethoxysilyl)propyl]amine, perfluorohexylethylene, and 3-bromopropene as raw materials, through addition and quaternization reactions, polymerizing with acrylic monomers, and then compounding with calcium ferrite cement, composite steel slag powder, and modified basalt fibers, etc.; the fluorinated quaternary ammonium salt siloxane modifier has relatively rich siloxane bond functional groups on the surface of the siloxane, which can undergo a condensation reaction with the silanol groups on the surface of the concrete substrate after hydrolysis, effectively filling the pores and cracks in the concrete material; the composite steel slag powder admixture has fine particles, which can make the system structure filled more tightly and improve the ability to hinder the penetration and diffusion of Cl ‑ ions; the modified basalt fibers improve the dispersion stability in the matrix and further improve the seawater erosion resistance of the concrete.

The invention belongs to the technical field of vanadium titano-magnetite sintering, and particularly discloses a method for preparing high-alkalinity sinter from low-iron high-titanium high-vanadium magnetite. The method for preparing the sintered ore provided by the invention comprises the following steps: crushing low-iron high-titanium high-vanadium magnetite, sulfuric-acid slag, a flux and a carbon-containing fuel; 20-40 parts of low-iron, high-titanium and high-vanadium magnetite, 6-20 parts of sulfuric-acid slag, 8-24 parts of flux, 2-4 parts of carbon-containing fuel and 6-12 parts of return mine are blended, and a mixture is formed; and adding water into the mixture, granulating to obtain a ball material, and sintering to obtain the sintered ore. According to the method, the solid waste sulfuric-acid residue is added in the ore blending process, element regulation and control of the sintered material are achieved, and resource reutilization of the solid waste sulfuric-acid residue can also be achieved; a flux is added in the sintering process, and high-quality binder phase calcium ferrite is generated under lower alkalinity by regulating and controlling sintering alkalinity and element composition, so that the strength performance of the sintered ore is effectively improved.

The present application belongs to the technical field of sinter production, and particularly relates to a production method of ultra-high basicity sinter for improving converter slagging, dephosphorization and reducing in-furnace spattering, which comprises the following steps: mixing 65% limonite powder, 20% magnetite powder and 15% blast furnace return fines, proportionally mixing 64% sintered mixture, 30% flux, 6% coke powder and 10% sintered internal return to prepare sintered mixed material, mixing and granulating under mist water according to a ratio of 7:3, and sintering under the condition that the thickness of the material layer is controlled to be 850 mm. The composition of the obtained ultra-high basicity sinter is as follows: CaO: 20% to 25%; SiO2: 5.5% to 6.6%; TFe: greater than or equal to 45%; basicity: 3.2 to 3.5; and drum strength: greater than or equal to 68. The micro-phase composition of the ultra-high basicity sinter is as follows: calcium ferrite: greater than or equal to 35%; dicalcium ferrite: 15% to 20%; dicalcium silicate: 10% to 20%; and iron oxide: less than or equal to 25%.

The invention provides an all-solid-waste metallurgical slag archaized brick and a preparation method thereof.The archaized brick is a substance with diopside, akermanite, calcium ferrite and corundum as phases formed by firing a compression molding substance of a silicon-manganese slag and magnesium slag composite material, and the preparation method comprises the steps that dried silicon-manganese slag and magnesium slag are mixed according to the mass ratio of (0-0.7): (1-0.3); pressing into a green body under the load of 8t, and sufficiently firing the green body at the temperature of 1100-1140 DEG C to obtain the archaized brick. By means of the scheme, the problems that a traditional archaized brick manufacturing process is complex and the investment cost is too high can be effectively solved, the all-solid-waste metallurgical slag archaized brick is prepared from the silicon-manganese slag, the magnesium slag and other solid waste raw materials, environmental pollution is reduced, the production cost is reduced, and finally energy conservation, environmental protection and economic benefits are doubly improved.

The present invention discloses a method for recycling rich iron red mud in the iron and steel industry. The present invention innovatively proposes adding rich iron red mud into a slag ladle and / or a ladle, mixing it with recycled refining slag, and using the heat of the recycled slag for premelting to form complex calcium ferrite with a low melting point phase, thus realizing a new idea of "double recycling" of rich iron red mud and refining slag. The premelted slag formed in the slag ladle is added to the converter, which is beneficial to the rapid slag melting of the slag in the early stage of converter blowing, improving the dissolution rate of lime as a slag-making material and the converter dephosphorization rate, and reducing the consumption of slag-making materials such as lime; the premelted slag formed in the ladle can provide favorable conditions for slag melting in the ladle dephosphorization and refining processes. The present invention realizes the common recycling of refining slag and rich iron red mud, achieving the purpose of disposing of rich iron red mud and recovering the molten steel remaining in the ladle, iron resources, and valuable minerals.

The invention discloses a method for preparing fluxed oxidized pellets based on hematite, and aims to solve the technical bottlenecks that high-proportion hematite pellets are difficult to grind and settle, high in roasting energy consumption and low in strength. The method comprises the following three core processes: S1, raw material pretreatment: performing wet ball milling, polyacrylamide-assisted sedimentation and ceramic vacuum filtration on coarse-grain hematite powder of which the particle size is less than 10mm, uniformly mixing with magnetite concentrate, and performing high-pressure roller milling treatment; s2, green pellets are prepared, specifically, the iron ore mixture is evenly mixed with bentonite, a calcium ferrite additive and a limestone flux, and qualified green pellets are prepared through a disc pelletizer; and S3, pellet roasting is conducted, specifically, green pellets are subjected to segmented drying, preheating and roasting in a chain grate-rotary kiln, and a finished product is obtained. According to the invention, the hematite with abundant reserves is used as a main raw material, and the compressive strength of the prepared oxidized pellets is more than 2500N / piece, the drum strength is more than 93%, the wear resistance index is less than 5%, and the prepared oxidized pellets have the cost advantage and the environmental protection benefit, and meet the high-efficiency smelting requirement of a blast furnace.

The invention discloses a converter indirect oxidation synchronous vanadium extraction and dephosphorization method based on composite calcium ferrite, which comprises the following steps: crushing and screening the composite calcium ferrite, adding the undersize product into a converter through a top feeding system, stirring a molten pool in cooperation with bottom blowing inert gas, and discharging the molten pool; the compound calcium ferrite is used for exerting the dual functions of an oxidizing agent and a dephosphorizing agent, and efficient and synchronous vanadium extraction and dephosphorizing are achieved in the single converter. According to the method, the oxidizing agent and the dephosphorizing agent are integrated into the composite calcium ferrite, so that the effects of extracting vanadium and dephosphorizing are achieved in the single adding process, synchronous vanadium extraction and dephosphorizing in the single converter are achieved, the process limitation of a traditional duplex converter is broken through, the operation process is simplified, the smelting efficiency is improved, and the advantages of energy conservation and cost are also achieved; and a new technical path is provided for efficient smelting of the vanadium-containing molten iron.

The invention provides a composite layered sintered ore and a preparation method and system.The preparation method comprises the steps that lump coal is crushed and screened, and lump coal particles are obtained; uniformly mixing an iron-containing raw material, a CaO-containing flux and fuel to obtain an outer-layer mixed material; feeding the lump coal particles into a disc pelletizer, and spraying atomized water to the surfaces of the lump coal particles until the surfaces of the lump coal particles are wet; spraying calcium ferrite to the surfaces of the lump coal particles; the outer-layer mixed material is added into a disc pelletizer, atomized water is continuously sprayed for pelletizing, screening is conducted after pelletizing is finished, and a green pellet mixed material is obtained; conveying the green pellet mixture to a sintering machine, igniting the green pellet mixture, and sintering the green pellet mixture under the condition of injecting hydrogen-rich gas to obtain high-temperature sintered ore; hydrogen is adopted as a cooling agent to cool the high-temperature sintered ore, and pre-reduction of the high-temperature sintered ore is achieved in the cooling process. According to the invention, the composite layered sintered ore has high strength and air permeability, and the coke ratio can be reduced while the lump coal ratio in the ironmaking process is increased.

The invention provides a composite layered pellet and a preparation method and system.The preparation method comprises the steps that lump coal is crushed and screened, and lump coal particles with the particle size ranging from 10 mm to 15 mm are selected; uniformly mixing the dried iron ore powder with a pelletizing agent to obtain an outer-layer mixed material; feeding the lump coal particles into a disc pelletizer, and spraying atomized water to the surfaces of the lump coal particles until the surfaces of the lump coal particles are wet; spraying calcium ferrite to the surfaces of the lump coal particles; the outer-layer mixed material is added into a disc pelletizer, atomized water is continuously sprayed for pelletizing, screening is conducted after pelletizing is finished, and green pellets with the size being 25-30 mm are obtained; roasting the green pellets in an oxidizing atmosphere to obtain high-temperature pellets; and hydrogen is adopted as a cooling agent to cool the high-temperature pellets, and pre-reduction of the high-temperature pellets is achieved in the cooling process. According to the invention, the composite layered pellet has high strength and air permeability, and the coke ratio can be reduced while the lump coal ratio in the ironmaking process is increased.

The invention discloses a process for firing sulfuric acid and co-producing calcium ferrite from ardealite, which specifically comprises the following steps: uniformly mixing ardealite with auxiliary materials such as sulfuric-acid residue, high-silicon material, pulverized coal and the like, preparing into a block mass, distributing, drying, roasting and cooling, the drying is divided into an air draft drying section and a forced air drying section, the drying hot air comes from circulating flue gas of different cooling sections, and the air draft drying section and the forced air drying section are communicated with the air draft drying section; the comprehensive energy consumption is effectively reduced, flue gas of a roasting section is derived from waste gas of a forced air drying section, SO2 in the flue gas can be enriched while flue gas circulation is achieved, high-sulfur flue gas is obtained, sulfuric acid is prepared through purification, conversion and absorption of the obtained high-sulfur flue gas, and calcium ferrite is obtained after an obtained solid roasted product is cooled. And resource recycling of calcium and sulfur in the phosphogypsum and iron and sulfur in the sulfuric-acid slag is realized with relatively low energy consumption.

This invention relates to the field of solid waste cementitious material preparation technology, specifically to a rapid-setting and hardening cementitious material based on calcium aluminoferrite from all solid waste and its preparation method, comprising the following steps: S1. Mixing and stirring modified red mud, carbide slag, mineral powder, and modified mineralizer evenly, and then pressing into shape; S2. Performing a first-stage calcination, calcining from room temperature to 950-1000℃, and then performing a second-stage calcination to 1220-1300℃ and holding at that temperature for 30-120 minutes, and cooling to room temperature to obtain modified mineral phase clinker; S3. Passing through a 200-mesh square hole sieve, mixing with modified multi-element solid waste mineral materials in a mixer, and stirring evenly to obtain the rapid-setting and hardening cementitious material based on calcium aluminoferrite from all solid waste. This invention significantly reduces the calcination temperature of clinker through the synergistic effect of various raw materials, thereby greatly reducing energy consumption and carbon emissions. The complex ionic reaction mechanism and the complementary physicochemical properties of multi-component solid waste enrich the diversity of hydration products and the density of the gel structure, thus ultimately achieving the excellent performance of "fast setting, fast hardening, and high strength" of the all-solid waste cementitious material.

The application relates to the technical field of wave-absorbing materials, in particular to a wide-band calcium ferrite wave-absorbing material and a preparation method and application thereof. 1.8 La 0.2‑x Ce x Fe2O5, wherein 0<=x<0.14. The application solves the problems of narrow absorption frequency band and low efficiency of the oxide wave-absorbing material by adjusting the composition and dielectric properties of the material through La and Ce double-element co-doping, and the prepared material has the advantages of wide absorption frequency band and high absorption intensity.

The invention relates to the technical field of metallurgical solid waste resource utilization, and discloses a method for preparing composite calcium ferrite by multi-source solid waste low-temperature catalysis, which comprises the following steps: respectively drying titanium gypsum and industrial copperas; adding the dried titanium gypsum, industrial copperas, carbon-containing reducing agent powder and a low-temperature mineralizer into a ball mill, and uniformly mixing and grinding to obtain a mixed and ground material; putting the mixed and ground material into a closed sintering device, introducing reductive protective gas, heating to a target temperature, preserving heat for a certain time, cooling along with a furnace to obtain composite calcium ferrite, collecting sulfur-rich flue gas generated by sintering, and preparing concentrated sulfuric acid by adopting a catalytic oxidation method. According to the method, by adding the low-temperature mineralizing agent and the reduction shielding gas, the calcination temperature and the heat preservation time for preparing the composite calcium ferrite from the titanium gypsum and the copperas are remarkably reduced, the reaction energy consumption is remarkably reduced, the solid waste treatment cost can be remarkably reduced, and the prepared composite calcium ferrite is used for sintering schreyerite to improve the performance of sintered ore.

The invention belongs to the technical field of ironmaking production, and relates to a whole concentrate sintering method. Comprising the following steps: (1) preparing a mixture A1 from ferroboron concentrate, brucite fiber, calcium ferrate, calcium peroxide and rare earth tailings, uniformly mixing, and grinding to prepare a sintering aid A; (2) preparing a mixture B1 from limestone powder, blast furnace fly ash, brucite fibers, magnesium humate and bentonite, uniformly mixing, and grinding to prepare a sintering binder B; (3) adding a sintering aid A and activated carbon powder into the iron ore concentrate to form a mixture C1, uniformly mixing and carrying out high-pressure roller milling to prepare pretreated ore concentrate C; (4) mixing the pretreated concentrate C, a fuel and an alkaline flux to form a mixture D1, adding a sintering binder B, uniformly mixing, and granulating to obtain a sintered material D; and (5) distributing, igniting and sintering to obtain a finished product sintered ore. According to the sintering method, the air permeability of a sintered material layer can be improved, the mineralization reaction condition of the sintered material is improved, the whole concentrate sintering index is improved, and the whole concentrate sintering solid fuel consumption is reduced.

The invention belongs to the technical field of vanadium-titanium sintering, and particularly relates to an additive for improving the performance of vanadium-titanium sinter and a preparation method and application thereof. In order to obviously improve the drum strength of the vanadium-titanium sinter and further improve the performance of the vanadium-titanium sinter, the invention provides an additive for improving the performance of the vanadium-titanium sinter, and the additive is obtained by mixing the following components in percentage by mass: 50-75% of composite calcium ferrite, 10-25% of waste glass powder, 10-20% of bentonite and 3-5% of quartz sand. When the additive prepared by the invention is added in a vanadium-titanium sinter sintering process, the drum strength of the sinter can be remarkably improved, the additive amount of the coke powder of the sinter is reduced, the quality of the sinter is improved, and a raw material foundation is laid for the stability of a blast furnace.

The present invention provides a physical-chemical and biochemical coupling process for removing hardness from coal gasification wastewater, belonging to the technical field of coal gasification wastewater treatment. Aiming at the characteristics of high hardness, high organic matter and high ammonia nitrogen in coal gasification wastewater, part of the pollutants are removed through pretreatment first. Then, a modified chitosan-nanocellulose composite template is added to the pretreated wastewater. The iron ions pre-loaded are used to provide nucleation sites, the biochar doping enhances adsorption and conductivity, and the three-level pore structure optimizes mass transfer, so as to efficiently adsorb calcium and magnesium ions and induce the formation of aragonite calcium carbonate precipitate. The precipitate is used as a biofilm carrier and filled into the anaerobic and aerobic two-stage biochemical reactors, and the supernatant is subjected to nitrification / denitrification treatment. Finally, the sludge is deeply treated and converted into a calcium ferrite photocatalyst to achieve resource utilization. The present invention can effectively remove COD, total hardness and ammonia nitrogen in coal gasification wastewater, and has a high sludge resource utilization rate, providing an efficient, economical and environmentally friendly solution for the treatment of coal chemical wastewater.

The application discloses a sintering oxidation catalyst for high-ratio magnetic concentrate and a use method thereof, which is composed of a sintering oxidizing agent and a sintering catalyst, and the preparation raw materials of the oxidizing agent include, in terms of weight fractions, 30-55 parts of calcium peroxide, 25-45 parts of magnesium peroxide, 2-15 parts of potassium permanganate and 2-12 parts of calcium ferrite; and the preparation raw materials of the sintering catalyst include, in terms of weight fractions, 30-60 parts of dolomite, 20-40 parts of iron powder, 10-20 parts of rare earth tailings and 5-15 parts of sintering dust removal ash. The sintering oxidation catalyst is prepared, the oxidizing agent adding proportion is optimized according to the high-low ratio of iron concentrate and the poor oxidation difference of the magnetic concentrate, the oxidation reaction capacity of the iron concentrate is improved, the sintering catalyst is prepared, the combustion efficiency of the solid fuel is improved, the sintering oxidation kinetics condition of the high-ratio magnetic concentrate is improved, and the sintering production efficiency and the sinter quality are improved.

The invention relates to the technical field of comprehensive utilization of steel slag, in particular to a method for separating ferrosilicon components in steel slag, which comprises the following steps: placing the steel slag and ore dissolving liquid in a reactor with an in-situ high shearing function, and adjusting the pH value of the reaction liquid through an ammonia distillation process, so that calcium silicate and calcium ferrite in the steel slag react to generate silica gel and ferrite; calcium ions in the steel slag are extracted into the solution, and a calcium extraction solution is obtained; separating the calcium extraction liquid according to the solid density to obtain a high-iron turbid liquid with high density and a high-silicon turbid liquid with low density; and respectively filtering the high-iron turbid liquid and the high-silicon turbid liquid, transferring the obtained filtrate into a carbon dioxide trapping system, regenerating the filtrate into ore dissolving liquid for reuse, and sufficiently washing the obtained filter cake to respectively obtain high-iron steel slag and high-silicon steel slag. The method for separating the silicon iron component in the steel slag has the beneficial effects that the calcium extraction rate is remarkably increased, the steel slag component is optimized, resource recycling is achieved, waste is reduced, and sustainable development of the iron and steel industry is promoted.

The application discloses a method for preparing calcium ferrite from vanadium-containing steel slag and calcium ferrite. The method comprises the following steps: directly injecting the molten vanadium-containing steel slag into an electric furnace; performing smelting treatment on the molten vanadium-containing steel slag in the electric furnace; performing air quenching treatment on the molten material after smelting to obtain granular material; and performing magnetic separation treatment on the granular material to separate and obtain steel slag powder and composite calcium ferrite. The scheme provided by the application directly uses the molten vanadium-containing steel slag as raw material, does not need to perform pretreatment such as cooling and crushing on the steel slag, fully utilizes the sensible heat of the molten steel slag, reduces heating energy consumption, and saves production cost. Meanwhile, the particle size of the material after the air quenching treatment is controllable, the proportion of fine powder is high, the magnetic separation efficiency is high, the process operation is simple, the process is short, and the scheme is suitable for industrial large-scale application. Thus, the high-value and resource utilization of the vanadium-containing steel slag, a metallurgical solid waste, are realized, and the environmental problems caused by the storage of the solid waste are reduced.

The application provides a method for synchronously preparing a metallurgical dephosphorizing agent by gasifying flue gas of a calcium-based reinforced metallurgical furnace and desulfurizing flue gas, and belongs to the technical field of metallurgical energy-saving and environmental protection. The method uniformly loads calcium-based materials on coal gasification raw materials through pretreatment loading, sprays the calcium-based materials into a metallurgical furnace gasification flue through a spraying system on the metallurgical furnace gasification flue, realizes coal gasification under the action of high-temperature flue gas, and the loaded calcium-based materials play a role in strengthening organic fuel cracking gasification in the process. Meanwhile, sulfur-containing flue gas released by the organic fuel is solidified by the calcium-based materials, the solidification products enter a dust removal system with dust, the calcium-based materials react with iron-containing components in the dust in the metallurgical furnace gasification flue to generate calcium ferrite with dephosphorizing metallurgical performance, and the calcium ferrite enters the dust removal system with the dust. The collected dust removal ash is used for high-value dephosphorizing agent production after being separated and purified through magnetic separation, and provides an effective way for the sustainability and economical production of the metallurgical industry.

The application provides a high-temperature tempering method for improving strong magnetic phase of steel slag, and relates to the technical field of steel slag resource utilization. The method is suitable for fresh molten steel slag or steel slag powder generated in a steelmaking workshop. The steel slag is placed in an environment with a temperature of 1000-1300 DEG C, 6%-14% of the mass of the steel slag is added with graphite or coke, and the mixture is stirred uniformly and kept for 10-90 min, and then the mixture is cooled. The operation can convert the weakly magnetic RO phase component and calcium ferrite component in the steel slag into strong magnetic phase such as metallic iron or magnetite, thereby improving the magnetism of the iron component in the steel slag, and further improving the subsequent magnetic separation effect, helping the iron recovery of the steel slag; and the steel slag with high activity and mainly composed of calcium silicate phase is obtained, which lays a foundation for the subsequent application of the steel slag in preparing low-carbon cementitious materials and the like. The method is simple and easy to operate, low in cost and energy consumption, and high in efficiency, and is beneficial to large-scale industrial production and popularization.

This invention relates to the field of solid waste cementitious material preparation technology, specifically to a rapid-setting and hardening cementitious material based on calcium aluminoferrite from all solid waste and its preparation method, comprising the following steps: S1. Mixing and stirring modified red mud, carbide slag, mineral powder, and modified mineralizer evenly, and then pressing into shape; S2. Performing a first-stage calcination, calcining from room temperature to 950-1000℃, and then performing a second-stage calcination to 1220-1300℃ and holding at that temperature for 30-120 minutes, and cooling to room temperature to obtain modified mineral phase clinker; S3. Passing through a 200-mesh square hole sieve, mixing with modified multi-element solid waste mineral materials in a mixer, and stirring evenly to obtain the rapid-setting and hardening cementitious material based on calcium aluminoferrite from all solid waste. This invention significantly reduces the calcination temperature of clinker through the synergistic effect of various raw materials, thereby greatly reducing energy consumption and carbon emissions. The complex ionic reaction mechanism and the complementary physicochemical properties of multi-component solid waste enrich the diversity of hydration products and the density of the gel structure, thus ultimately achieving the excellent performance of "fast setting, fast hardening, and high strength" of the all-solid waste cementitious material.

The invention relates to a method for improving the dissolution rate of lithium in bauxite, and belongs to the technical field of aluminum oxide industry. The method comprises the following steps: obtaining lithium-containing bauxite; mixing the lithium-containing bauxite, calcium ferrite and circulating mother liquor to obtain a mixture; wherein the mass of the calcium ferrite is 1%-8% of the mass of the lithium-containing bauxite; the mixture is subjected to ball milling, and raw ore pulp is obtained; the raw ore pulp is sequentially subjected to pre-desilicication and dissolution treatment, and dissolution ore pulp is obtained; carrying out solid-liquid separation on the dissolved-out ore pulp to obtain a lithium-containing sodium aluminate solution; and lithium ions in the lithium-containing sodium aluminate solution are sequentially enriched and precipitated, so that the lithium ions in the lithium-containing sodium aluminate solution are separated. According to the method, calcium ferrite is added in the ball milling process, and then pre-desiliconization and dissolution treatment are carried out, so that the effect of improving the dissolution rate of lithium is achieved.

The invention provides a method for preparing a dephosphorizing agent from iron-containing solid waste, the dephosphorizing agent and a converter steelmaking method, and belongs to the technical field of smelting. The method comprises the following steps: mixing iron-containing solid waste, lime, limestone and coke according to a set mass ratio to obtain a mixture; mixing the mixture with a solvent, and granulating to obtain granules; and sintering the granules to obtain the dephosphorizing agent. The raw material composition of the dephosphorizing agent is reasonably designed, the iron-containing solid waste and the lime can generate calcium ferrite with good slagging and dephosphorizing capacity in the sintering process, the alkalinity of the dephosphorizing agent can be improved through the mass ratio, dephosphorizing reaction in a converter is facilitated, and meanwhile the high-temperature strength and other performance of the dephosphorizing agent can be improved through the existence of the limestone. The obtained dephosphorizing agent can be used for the dephosphorizing process of converter smelting, the feeding amount of the iron-containing solid waste of the steel plant in the converter is increased, and efficient cyclic utilization of solid waste resources in the steel plant is achieved.

A dicalcium ferrite (Ca2Fe2O5) / calcium ferrite (CaFe2O4) / iron oxide (Fe2O3) nanocomposite material includes orthorhombic Ca2Fe2O5 phases, orthorhombic CaFe2O4 phases, and rhombohedral Fe2O3 phases. The Ca2Fe2O5 / CaFe2O4 / Fe2O3 nanocomposite material has a granular morphology with an average grain size in a range from 200 to 400 nanometers (nm) and the granular morphology includes spherical particles aggregated together forming the granular morphology where the spherical particles have an average particle diameter in a range from 40 to 80 nm.

The invention belongs to the crossing field of solid waste resource utilization and novel cementing materials, and particularly relates to an aluminum-rich activator for accelerating hydration of converter slag, a converter slag cementing material and application, and the activator is soluble metaaluminate capable of hydrolyzing [Al (OH) 4] <->. The activator can regulate and control the Al / Fe ratio in a converter slag system, so that the traditional hydration path of dicalcium silicate is changed, and synergistic excitation of dicalcium silicate and calcium aluminoferrite is realized. The early-stage hydration reaction activity of the converter slag can be remarkably improved, so that the early-stage and later-stage compressive strength is remarkably improved. Therefore, the metaaluminate excitant can greatly accelerate the development of early strength and obviously enhance the final mechanical property. The compactness of hardened slurry is improved, so that a microstructure foundation is provided for improving the mechanical property and durability. Effective solidification of heavy metal is achieved, and the core problems of low early strength and heavy metal precipitation in the converter slag resource utilization process are solved.

The present invention belongs to the technical field of converter steelmaking, and specifically relates to a smelting method for reducing the consumption of converter steel materials. The converter scrap ratio is controlled at 15-25%, and the oxygen supply flow rate is controlled at 5.0-6.0 Nm 3 / (min•t), adding calcium ferrite dephosphorization agent and calcium ferrite slag-forming agent containing CaO·SiO2 in the smelting process can quickly form slag and improve the slag-forming effect. At the same time, combined with appropriate feeding system and oxygen supply system, it can improve the dephosphorization effect while reducing the amount of converter steelmaking slag and the total iron content of the slag.