38 results about "Calcium ferrite" patented technology

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 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 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 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 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 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.

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.

This invention discloses a method for preparing calcium ferrite from iron-based solid waste through low-temperature catalytic decomposition of phosphogypsum, belonging to the field of comprehensive utilization of solid waste. The method involves mixing, granulating, and roasting raw materials, including iron-based solid waste and phosphogypsum, to obtain calcium ferrite-containing sintered material. The roasting process involves feeding the material onto a belt roaster, first performing reduction roasting under a reducing atmosphere, and then performing oxidative roasting under an oxidizing atmosphere. This method fully utilizes the mineral composition characteristics of iron-based solid waste and phosphogypsum from the steel industry. By controlling the temperature and atmosphere during the high-temperature solid-phase reaction, the method achieves the directional transformation of iron and calcium components in the two industrial solid wastes into calcium ferrite-based products, while effectively removing harmful elements, resulting in high-quality calcium ferrite products.

The invention provides a comprehensive evaluation method for the high-temperature metallurgical performance of vanadium-titanium sinter for a blast furnace, and belongs to the technical field of steel smelting. Carrying out dimensionless grading treatment on the data of the tested sample; establishing a comprehensive evaluation index H of the high-temperature metallurgical performance, the calcium ferrite content w of the vanadium-titanium sinter, the total indirect reduction degree sigma Ri, the air permeability characteristic value Da of a melting zone, the soft melting temperature interval delta Ts and the melting finishing temperature Tm; evaluating the high-temperature metallurgical performance of the to-be-measured vanadium-titanium sinter according to the H value; a plurality of key parameters such as the calcium ferrite content, the total indirect reduction degree, the melting zone air permeability characteristic value, the soft melting temperature interval and the melting finishing temperature are introduced, and after dimensionless grading is conducted, a comprehensive evaluation index H is established, so that the high-temperature metallurgical performance of the vanadium-titanium sinter is comprehensively reflected, and the high-temperature metallurgical performance of the vanadium-titanium sinter is improved. The problem that complex reaction conditions in the blast furnace are difficult to accurately reflect by a traditional method is solved.

Provided is a blast furnace operation method with which it is possible to reduce CO2 emissions. A method for operating a blast furnace in which molten iron is produced by supplying a gaseous reducing agent from the lower part of a blast furnace while charging an artificial lump ore from the top of the blast furnace, the amount of supply of the gaseous reducing agent being 100 Nm3 / t or more, and the phase fraction of a calcium ferrite phase or a secondary hematite phase of the artificial lump ore being within a predetermined range.

The invention relates to the technical field of hazardous waste harmless treatment and comprehensive utilization of resources, in particular to a method for synergistic harmlessness of waste incineration fly ash and steel-making furnace dust and preparation of sintered-grade calcium ferrite, which comprises the following steps: S100: carrying out raw material compatibility according to mineral phase composition of waste incineration fly ash and steel-making furnace dust to obtain a uniform mixture; s200, the obtained mixture is supplemented with inert gas flow, and the mixture is fed into a high-temperature area to be roasted; s300, after calcification-chlorination composite activation high-temperature roasting, activated zinc-lead-potassium-sodium-rich phase and stable-phase dicalcium ferrite are generated; s400, the activated phase sublimates to a low-temperature area along with inert gas flow to be desublimated and separated from tailings, and purification is achieved; according to the method, the waste incineration fly ash and the steelmaking furnace dust are subjected to synergistic harmlessness, and meanwhile, the alkaline oxide and the iron-containing oxide are combined and can serve as an iron-containing raw material and an alkaline flux in the sintering process. According to the method, the hazardous waste can be synergistically self-treated and converted into an iron-making process raw material-level resource, the environmental protection benefit is outstanding, and certain economic benefits are achieved.

The invention provides a process for producing zinc hypoxide from zinc-containing waste through a rotary kiln reduction fuming method, and belongs to the technical field of zinc hypoxide production. The method comprises the following steps: mixing blast furnace gas ash with activated aluminum oxide, calcium ferrite and anthracite duff to prepare composite pellets; in a rotary kiln, the pellets utilize a temperature gradient formed by countercurrent heat exchange to sequentially trigger reactions of three stages: firstly, alkali metal is fixed in situ through activated aluminum oxide in a low-temperature area to prevent ring formation; then, reducing activation energy of a carbon gasification reaction in a medium-temperature region by utilizing the catalytic action of calcium ferrite, activating and accelerating the reaction of carbon and carbon dioxide, and reacting with non-volatile components in a high-temperature region to form stable slag; and finally, the zinc oxide is efficiently reduced into zinc steam in the high-temperature area, the zinc steam is oxidized into secondary zinc oxide dust by the oxidizing atmosphere in the upper space in the kiln, and the secondary zinc oxide dust enters a rear-end system along with flue gas to be cooled and collected.

This invention provides a ground improvement material that can reduce CO2 emissions and a method for manufacturing the same. [Solution] A ground improvement material comprising a solidifying agent containing blast furnace slag fine powder and steelmaking slag fine powder, and water, wherein the steelmaking slag fine powder contains at least one or more of the following: free lime, calcium hydroxide, calcium ferrite, calcium silicate, and dicalcium silicate.

This invention discloses a production method, the resulting product, and its application in the field of iron and steel metallurgical technology, which utilizes the waste heat from steel slag for temperature control. The invention calculates the amount of siderite that can be added based on the temperature and mass of the steel slag, then places the siderite on top of the liquid steel slag. It calculates the corresponding slag temperature during slag cooling and adds coke tailings at 1210℃ and 600℃, with the amount of coke added being 5% of the siderite mass. After crushing and cooling, the steel slag is magnetically separated to obtain iron ore. The remaining non-magnetic steel slag is the slagging agent, with calcium ferrite as its effective component. This invention utilizes the absorption of waste heat from steel slag by siderite, combined with temperature control, to efficiently recover waste heat from steel slag and process siderite at low cost. The resulting products are iron ore and a slagging agent that can be directly fed into the furnace, bringing significant economic value to enterprises and making a significant contribution to energy conservation and emission reduction in the steel industry.

The invention discloses a method for preparing calcium ferrite and co-producing sulfuric acid by using titanium gypsum, which comprises the following steps: reacting titanium gypsum with an ammonium salt solution to obtain a solid-phase product I and an ammonium sulfate solution, carrying out liquid-solid separation, and carrying out calcination reaction on the solid product I and an iron-containing material to obtain a calcium ferrite product and CO2. The method comprises the following steps: carrying out evaporative crystallization on an ammonium sulfate solution to obtain a solid product II and water, mixing the solid product II with ferric oxide, carrying out primary calcination to obtain a solid product III and ammonia water, carrying out secondary calcination on the solid product III to obtain ferric oxide and SO2, recycling ferric oxide, and using sulfur dioxide for preparing acid. CO2 and ammonia water are combined to generate an ammonium salt solution, and the ammonium salt solution is recycled. According to the method, resource recycling and innocent treatment of the titanium gypsum are achieved, meanwhile, collaborative recycling and closed-loop recycling of resources such as calcium, iron, sulfur and carbon are achieved, emission of solid waste and secondary salt is remarkably reduced, the emission intensity of pollutants such as sulfur dioxide and carbon dioxide is reduced, and the obtained calcium ferrite product is high in purity.