50 results about "Hematite" patented technology

The invention belongs to the field of biochar adsorbing materials, and relates to a method for preparing modified biochar with aquatic plant waste and hematite. The method includes the following steps: (1) naturally drying aquatic plants prior to crushing to obtain aquatic plant powder; (2) crushing the hematite to obtain hematite powder; (3) weighing the hematite powder prior to putting the hematite powder into deionized water, and performing ultrasonic treatment to obtain suspension; (4) weighing the aquatic plant powder, soaking the aquatic plant powder in the suspension, and stirring and drying to obtain fully mixed aquatic plant and hematite mixture; (5) weighing the fully mixed aquatic plant and hematite mixture, putting the mixture in a batch-type atmosphere furnace, and feeding nitrogen into the furnace; performing temperature programming to the target temperature, and maintaining final-temperature pyrolysis; after the pyrolysis process is finished, obtaining the target product, namely the modified biochar. The modified biochar has strong adsorbability in nitrate and phosphate, high in stability and reusable.

The invention discloses a Mars soil simulant performance evaluation method based on spectrum-mechanics combined characterization, which comprises the following steps: acquiring surface soil chemical components and physical and mechanical reference data of a target Mars area, taking basalt, magnetite and hematite as raw materials, solving the optimal mass ratio by adopting an optimization algorithm, and preparing a sample. Then, systematic spectrum characterization is carried out on the sample, and components and spectrum characteristic data of the sample are obtained; and meanwhile, carrying out physical and mechanical property test on the sample to obtain mechanical property data. Further, spectrum and component data serve as independent variables, mechanical data serve as dependent variables, an associated data set is constructed, the influence weight is analyzed, and a component-structure-performance quantitative relation is established. And finally, based on all the data and the internal association thereof, calculating the comprehensive similarity between the simulant and the real Mars soil, and generating a comprehensive performance evaluation report. According to the method, multi-dimensional and standardized quantitative evaluation of chemical, mineral and mechanical properties of the Mars soil simulants is realized.

The invention relates to the technical field of red mud recycling, in particular to a method for improving magnetic separation iron extraction efficiency by modifying red mud through industrial kiln tail gas CO2. The invention discloses a method for improving magnetic separation iron extraction efficiency by using industrial kiln tail gas CO2 modified red mud, which comprises the following steps: collecting tail gas discharged in the calcining process of an industrial kiln, and sequentially carrying out dust removal, desulfurization and compression to obtain compressed tail gas; the method comprises the following steps: mixing red mud with water, introducing compressed tail gas, and carrying out carbonization reaction at 60-80 DEG C to obtain carbonized modified red mud slurry; and the carbonized modified red mud slurry is placed in a high-gradient magnetic separator for magnetic separation, and refined iron powder is obtained. By means of the method, resource utilization of industrial kiln tail gas CO2 and efficient quality improvement of the red mud can be achieved, a dense alkali film wrapping hematite in the red mud is stripped, the hematite crystal structure is optimized, and meanwhile the iron extraction cost of the red mud and carbon emission of an industrial kiln are reduced.

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 present application relates to the technical field of mineral processing, and particularly relates to a modified dodecylamine collector, a preparation method and application thereof.The preparation method of the modified dodecylamine collector provided by the present application comprises the following steps: carrying out glow discharge air plasma treatment on dodecylamine by taking air as a working gas.The present application introduces oxygen-containing and / or nitrogen-containing active groups on the surface of dodecylamine molecules by means of glow discharge air plasma modification of dodecylamine, and the dodecylamine is used for flotation separation of quartz and hematite, so that the adsorption capacity and selectivity of the dodecylamine to quartz, especially fine quartz, are enhanced, and efficient separation of quartz and hematite can be realized at a lower dosage; and the raw material of the preparation method is green and environmentally friendly, the modification process is low-temperature, safe and controllable, no by-product is generated, and the energy consumption is low.

The invention relates to a magnetic material comprising at least iron, in metal form and / or in oxide form, and at least one clay matrix, the iron content being between 15% and 70% by weight of iron element relative to the total weight of said material, characterized in that said material has a specific surface area greater than 1 m² / g and less than 50 m² / g, and said material is in the form of beads or extrudates, and in that said material comprises at most 25% by weight of hematite relative to the total weight of said material.

The invention relates to the technical field of metallurgical solid waste resource utilization, in particular to a method for enriching iron in vanadium extraction tailings and spiral separation equipment, and the method comprises the following steps: pretreatment, crushing and screening: feeding the vanadium extraction tailings into a jaw crusher for coarse crushing until the particle size is less than or equal to 50mm; the particle size of a crushed product is controlled to be smaller than or equal to 10 mm, the fine crushed product is screened through a linear vibrating screen, the size of a screen hole is 2 mm, oversize products return to the impact crusher to be crushed again, undersize products enter the next step, large gangue and impurities in the tailings can be removed in the step, and energy consumption is reduced for follow-up ore grinding operation. The combined technological process of pretreatment, magnetic separation roughing, spiral gravity separation and magnetic separation concentration is adopted, strong magnetic minerals are rapidly recovered through magnetic separation, then spiral gravity separation is adopted for weak magnetic and intergrowth minerals, the advantages of different separation technologies are fully played, and the problem that the recovery rate of the weak magnetic minerals such as hematite is low through a single magnetic separation method is solved.

The invention relates to a magnetic material comprising at least iron, in metallic form and / or in oxide form, and at least an alumina oxide matrix, the iron content being between 15% and 70% by weight as element iron relative to the total weight of said material, characterized in that said material has a specific surface area greater than 50 m² / g and less than 300 m² / g, said material is in the form of beads or extrudates, and in that said material comprises at most 25% by weight of hematite relative to the total weight of said material.

The disclosed ore-dressing plant process arrangement includes multiple process platforms and multiple material conveying channels. The multiple process platforms are sequentially arranged from top to bottom along the terrain. The multiple process platforms include at least a first process platform, a second process platform, a third process platform, and a fourth process platform. The first process platform is provided with a magnetite grinding and separation unit. The second process platform is provided with a hematite grinding and separation unit. The third process platform is provided with a hematite gravity separation unit. The fourth process platform is provided with a hematite flotation unit. The multiple material conveying channels are used to connect the multiple process platforms. The elevations of the multiple process platforms sequentially decrease along the material flow direction, so that the materials between the process platforms can be self-flow conveyed. The disclosed ore-dressing plant process arrangement sequentially arranges multiple process platforms from top to bottom according to the terrain, and uses the terrain difference for stepwise arrangement, to realize self-flow conveying of the ore slurry, reduce the energy consumption of the ore slurry conveying, and reduce the cost.

The invention relates to a magnetic material comprising at least iron, in metal form and / or in oxide form, and at least one alumina oxide matrix, the iron content being between 15% and 70% by weight of iron element relative to the total weight of said material, characterized in that said material has a specific surface area greater than 50 m² / g and less than 300 m² / g, and said material is in the form of beads or extrudates, and in that said material comprises at most 25% by weight of hematite relative to the total weight of said material.

The invention discloses an iron oxide ore combined collecting agent and application thereof, and belongs to the technical field of mineral flotation. According to the combined collecting agent, a multi-element mixed coordination field is constructed through dihydroxamic acid and oximido, a stable composite adsorption layer is formed, and meanwhile, a dense hydrophobic layer is constructed on the surface of a mineral through the hydrophobic synergistic effect of a flexible aliphatic chain and a rigid benzene ring. The application of the combined collecting agent in iron oxide ore flotation comprises the steps that after iron oxide ore is smashed and subjected to size mixing, the combined collecting agent and a foaming agent are added, an oxidizing agent can also be added, and concentrate is obtained after air inflation flotation. The combined collecting agent can achieve efficient flotation of ilmenite, hematite and siderite under the mild condition, and has the advantages of being good in selectivity, high in recovery rate, small in dosage and environmentally friendly.

The present application relates to the technical field of mineralogy, and particularly provides a complex iron mineral distinguishing and quantifying method and an iron mineral content analysis method, which combines chemical dissolution, automatic mineralogy analysis and micro-area magnetic verification technology for the first time to realize the distinguishing and quantifying of complex iron minerals. The analysis method constitutes a closed and mutually checked analysis system, which combines acid treatment of carbonates, automatic mineralogy analysis of residual minerals, micro-area magnetic verification to correct the misjudgment of magnetic hematite, element surface scanning to check the accuracy of overall mineralogy quantification, and final calculation results, and checks the total iron content of chemical analysis to ensure the reliability of the final results and facilitate the standardized popularization and application.

The present application relates to the technical field of goethite, and provides a goethite, a preparation method and application, the preparation method comprises the following steps: S1, coarse crushing of limonite, sieving, to obtain a coarse crushing sample; S2, fine crushing and grading sieving, to obtain a plurality of batches of fine sieving samples; S3, heating and heat preservation of the fine sieving samples; S4, magnetic separation of the fine sieving samples, and weakly magnetic hematite and strongly magnetic substances are extracted together; S5, repeating steps S3 and S4 until the content of the remaining magnetic substances is within a set threshold; S6, cooling the fine sieving samples to below the Neel temperature of goethite, and then performing magnetic separation again to separate goethite. The present application has the advantages of large processing capacity, high processing efficiency, continuous production, and significantly reduced difficulty in obtaining goethite. In addition, compared with the traditional hydrothermal synthesis method, the present application removes the use of chemical products, effectively reducing the environmental problems in the production process of goethite.

The invention relates to a magnetic material comprising at least iron, in metal form and / or in oxide form, at least one oxide matrix, the iron content being between 15% and 70% by weight of iron element relative to the total weight of said material, and at least silicon carbide in its alpha (α-SiC) crystallographic form, characterized in that said material comprises at most 25% by weight of hematite relative to the total weight of said material, said material being in the form of beads or extrudates.

This invention belongs to the field of metallurgical solid waste resource utilization technology, specifically disclosing an iron-based additive, its preparation method, and its application. The preparation method includes: mixing red mud, sodium salt, and a reducing agent; subjecting the mixture to reduction roasting to obtain reduced clinker; grinding and separating the reduced clinker by magnetic separation to obtain iron concentrate, thus obtaining the iron-based additive. This invention uses red mud, sodium salt, and a reducing agent stored in alumina plants as raw materials. The sodium salt significantly lowers the reduction temperature of iron ore, and by controlling the temperature and the amount of reducing agent added, the hematite is partially or completely reduced. The resulting iron-based additive is returned to the Bayer process leaching, which can significantly improve the alumina leaching rate. Simultaneously, the titanium minerals in the obtained titanium-containing tailings exist in a specific phase or in the form of amorphous sodium titanate, exhibiting higher reactivity. This invention realizes the recycling and value-added utilization of solid wastes such as red mud, and has good application prospects.

To produce sintered ore having higher quality by using a mixed dry distilled material obtained by mixing iron ore with biomass and dry distilling the mixture.SOLUTION: A particle size adjustment step of adjusting the particle size of the biomass and the iron ore to a predetermined particle size, a carbonization step of carbonizing a mixture of the biomass and the iron ore having the adjusted particle size to produce a mixed carbonized product which is a mixture of a biomass carbide and a reduced ore, and a sintering step of producing sintered ore using the mixed carbonized product, wherein the predetermined particle size of the biomass is a top size of 3 mm or more and 7 mm or less, and the predetermined particle size of the iron ore is a top size of 7 mm or more and 10 mm or less, wherein a particle diameter ratio of a top size is 0.3 or more, a mass ratio of the biomass and the iron ore in the mixture is 0.2 or more, a dry distillation temperature in the dry distillation step is 700 °C or more and 900 °C or less, and a reduction rate of the reduced ore produced in the dry distillation step based on hematite is 70% or less.SELECTED DRAWING: Figure 1

This invention belongs to the field of iron ore sintering technology and discloses a method for strengthening the sintering of high-ratio specular hematite. S1. Raw material pretreatment: Returned ore and dried limonite are sieved using a 0.25mm sieve. Returned ore and limonite with a particle size smaller than 0.25mm are mixed with specular hematite powder and then pretreated by high-pressure roller milling. S2. Mixing and granulation: The mixture is mixed with returned ore and limonite larger than 0.25mm, other iron-containing minerals, flux, and fuel, and then granulated. S3. Pre-oxidation: The granulated mixture is distributed, and after distribution, the material layer is pre-oxidized using hot air. S4. Sintering: The mixture undergoes ignition, sintering, crushing, and cooling sequentially to produce the finished sintered ore. This invention effectively improves the proportion of specular hematite, significantly reduces sintering energy consumption, and increases the strength of the sintered ore.

The invention relates to the field of magnetic simulation, in particular to a magnetic simulation method for simulating a low-temperature oxidized geological sample, which comprises the following steps: S1, constructing a double-layer model in Cubit software; s2, setting interface exchange interaction constants corresponding to three exchange types including no exchange, weak exchange and uniform exchange for the double-layer structure; s3, hysteresis parameters under the three exchange interaction constants are calculated, and the numerical calculation result of which exchange constant is closer to the experimental result / literature result is judged; s4, constructing a complex multi-layer low-temperature oxidation model in Cubit software; s5, constructing a low-temperature oxidation process model based on the theoretical oxidation kinetics model and simulating particles with various particle sizes; s6, comparing a simulation result with a hysteresis parameter measured by an experiment; and S7, drawing a multi-particle-size micro-magnetic structure chart and a multi-particle-size hysteresis loop. According to the method, the oxidation process is refined, a double-layer core-shell structure of magnetite and maghemite can be constructed, and a particle aggregation model is established.

The invention relates to a magnetic material comprising at least iron, in metallic form and / or in oxide form, and at least a clay matrix, the iron content being between 15% and 70% by weight as element iron relative to the total weight of said material, characterized in that said material has a specific surface area greater than 1 m² / g and less than 50 m² / g, said material is in the form of beads or extrudates, and in that said material comprises at most 25% by weight of hematite relative to the total weight of said material.

The application discloses a method for improving hydrogen-based shaft furnace oxidized pellet whole ball rate, belonging to the technical field of steel metallurgy, comprising the following steps: S1, mechanically activating hematite and magnetite concentrate after ore blending, mixing the mechanically activated iron ore raw material, binder and flux, and then pelletizing to obtain qualified green balls; S2, sequentially drying and preheating roasting the green balls obtained in step S1 to obtain preheated pellets; S3, oxidizing roasting the preheated pellets obtained in step S2 to obtain oxidized pellets; S4, detecting hydrogen-based reduction behavior of the oxidized pellets obtained in step S3. The application adopts the ore blending scheme of hematite + magnetite concentrate through the mechanical activation + chemical activation + ore blending coupling process, the high-grade magnetite concentrate is high in price and low in resources, and the hydrogen-based reduction whole ball rate of the high-grade pellet can be greatly improved without changing the existing main process and formula. The scheme is simple in process, easy to transform, controllable in cost, and has excellent industrial application prospect.

The present invention provides a method and apparatus for producing iron from an iron ore, together with an option for the onward conversion of that iron into steel. The iron may come from an iron ore in which the iron is present as at least one of the mineral and mineraloid forms of iron oxide and iron oxyhydroxide, such as hematite and limonite, as well as from red bauxite. The invention may also be used to produce elemental iron from other sources of iron oxide, such as from mill scale, whereby sources of waste iron oxide may be recycled. The method comprises comminuting the iron ore into fines, dehydrating the iron ore and dehydroxylating hydroxylated compounds in the ore. The ore thus treated is then reacted with an amount of liquid sodium in excess of the stoichiometric amount thereof required for a redox reaction between the liquid sodium and iron oxide(s) from the ore. This precipitates out from the liquid sodium both elemental iron and other insoluble products at least comprising sodium oxide. The redox reaction is conducted in an inert atmosphere and its temperature is controlled to remain below about 450 °Celsius to inhibit the production of ternary oxides like Na4FeO3. The method then comprises separating the iron from the other insoluble products, for example using magnetic and / or density-based separation, and separating the iron and the other insoluble products as a solid phase from the liquid sodium, in any order. Thus iron can be extracted from iron ore without producing any greenhouse gas emissions, and sodium oxide, which has a high affinity for carbon dioxide, is produced as a co-product. Since the iron is produced as a finely divided particulate, it may subsequently be converted into steel using a powder metallurgical technique with a considerable energy saving over prior art steelmaking techniques. If the sodium oxide is used to mineralize captured carbon dioxide, the invention can have a negative carbon footprint overall. If the iron ore comprises red bauxite, the other insoluble products may also be processed to extract alumina from them without creating environmentally hazardous red mud. In some embodiments, the other insoluble products may be used to produce an alkaline activator for an alkaline activated or geopolymer cement. The corresponding apparatus (3a) comprises a comminution device (2) (such as a rock crusher or grinder), a dryer (4) for dehydrating and dehydroxylating the iron ore, a gas-tight reaction vessel (130) for reacting the treated ore with the liquid sodium, a solid-species separator (180a) for separating the iron from the other insoluble products and a solid-liquid sodium phase separator (190a, 190b).

The application discloses a method for cooperatively roasting and magnetically separating and enriching gold and iron by using carbonaceous gold ore and cyanidation tailings, fully utilizes the mineralogical characteristics of the carbonaceous gold ore and the cyanidation tailings, and roasts the carbonaceous gold ore and the cyanidation tailings after cold-pressing and forming in an air-tight manner, so that the hematite in the cyanidation tailings is controllably reduced into magnetite by carbonaceous substances and pyrite in the carbonaceous gold ore, iron concentrate is obtained through roasting, grinding, screening and magnetic separation, and gold is maximally enriched in the tailings of the magnetic separation and is recovered through a subsequent leaching process. In the roasting process, the hematite in the cyanidation tailings and the pyrite in the minerals have redox reactions with carbon monoxide, elemental carbon and the pyrite generated by pyrolysis of the organic carbon, which not only eliminates the gold-killing effect of the organic carbon, but also destroys the pyrite and hematite inclusions of gold, and simultaneously realizes the efficient separation and comprehensive utilization of gold and iron in the carbonaceous gold ore and the cyanidation tailings.

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 present application relates to the technical field of mineral processing, and particularly relates to a modified dodecylamine collector, a preparation method and application thereof.The preparation method of the modified dodecylamine collector provided by the present application comprises the following steps: carrying out glow discharge air plasma treatment on dodecylamine by taking air as a working gas.The present application introduces oxygen-containing and / or nitrogen-containing active groups on the surface of dodecylamine molecules by means of glow discharge air plasma modification of dodecylamine, and the dodecylamine is used for flotation separation of quartz and hematite, so that the adsorption capacity and selectivity of the dodecylamine to quartz, especially fine quartz, are enhanced, and efficient separation of quartz and hematite can be realized at a lower dosage; and the raw material of the preparation method is green and environmentally friendly, the modification process is low-temperature, safe and controllable, no by-product is generated, and the energy consumption is low.

The invention discloses a method for removing iron from hematite in wet-process zinc smelting, and relates to the technical field of wet-process zinc smelting. The method comprises the following steps: (1) carrying out fluidized bed roasting on first zinc sulfide concentrate to obtain roasted sand; (2) the roasted sand is subjected to neutral leaching, and neutral leaching residues are obtained; (3) the neutral leaching residues are subjected to neutral leaching residue acid leaching treatment, and leachate is obtained; (4) preparing a mixture of the leachate and a neutralizer, and carrying out pre-neutralization treatment to obtain a pre-neutralized solution; and (5) the pre-neutralization liquid is subjected to hematite iron removal treatment. Therefore, use of gypsum residues can be avoided, and meanwhile efficient leaching of zinc and effective recovery of iron are achieved.

A process for converting a hematite-containing material to a maghemite-containing material is developed. The process comprises: producing a crushed hematite-containing material by crushing the hematite-containing material utilizing a means for grinding, obtaining a hematite-containing material with a particle size in a range of 150 µm to 500 µm by sieving the crushed hematite- containing material utilizing a means for sifting, and exposing the hematite-containing material with the particle size of 150 µm to 500 µm to a microwave energy with a frequency in a range of 890 MHz to 930 MHz for an exposing time in a range of 30 seconds to 360 seconds utilizing a means for radiating a microwave beam. An exposed thickness of the hematite-containing material with the particle size of 150 µm to 500 is a range of 3 cm to 10 cm that has a particular effect on phase changing of the hematite to the maghemite.

The invention relates to the technical field of lunar soil preparation, in particular to a simulated lunar soil preparation method based on nonferrous metal tailings. Comprising the following steps: grinding and screening nonferrous metal tailing powder; mixing the non-ferrous metal tailing powder with the plagioclase powder, the pyroxene powder, the olivine powder and the hematite powder in proportion, and grinding; uniformly mixing the mixed powder with graphite powder to obtain composite powder containing elemental iron, and uniformly mixing ilmenite powder with carbon black powder to obtain composite powder containing coexisting elemental iron and ilmenite; and uniformly mixing the two kinds of powder, performing low-intensity magnetic separation, ball-milling and screening, and mixing according to a specified particle size distribution ratio to obtain the lunar soil simulant. Not only is efficient resource utilization of the nonferrous metal tailings realized, but also simulated lunar soil with matched components and stable performance can be prepared.

The invention discloses a method for preparing pellets by using high-silicon hematite. The method comprises the following steps: proportioning the following raw materials in percentage by mass: 8% of high-silicon hematite concentrate, 50%-55% of magnetite concentrate A, 10%-25% of magnetite concentrate B, 20%-30% of magnetite concentrate C and 2%-4% of bentonite; fully and uniformly mixing the raw materials through a vertical mixer; the high-silicon hematite concentrate is TFegt prepared after high-silicon hematite fine ore is subjected to an ore grinding and beneficiation process; the iron ore concentrate comprises the following main components in percentage by mass: 10 to 12 percent of SiO2, 0 to 0.5 percent of CaO, 2.0 to 2.5 percent of Al2O3, 0.8 to 1.8 percent of Ig and FeOlt; and the passing rate of a 200-mesh screen is higher than 70%. The invention aims to effectively reduce the reduction expansion rate of the pellets and reduce the production cost of the pellets under the condition of ensuring that the quality index of the pellets meets the smelting requirement of a blast furnace.

Provided is an agglomerated ore for a blast furnace, the agglomerated ore having higher reducibility. The agglomerated ore for a blast furnace has a cross-sectional structure in which the area ratio of hematite is 40% or more and the area ratio of magnetite is 30% or less, wherein the average Feret diameter of hematite particles in the cross-sectional structure is 30 μm or more as calculated from the distribution of crystal orientations of the hematite.

This invention provides a mineral processing method for steadily improving the production indicators of fine-grained hematite, characterized by the following steps: 1) roughing of hematite, 2) regrinding of hematite, 3) overflow thickening, 4) producing hematite concentrate with a grade of 40%, 5) rough flotation, 6) producing hematite concentrate with a grade of 60%, and 7) scavenging. While increasing the yield of hematite concentrate, this method significantly increases the iron content of the hematite concentrate to 60% and reduces the SiO₂ content to below 6%. It also produces hematite concentrate with a grade of 40%, improving resource utilization efficiency and producing multiple grades of hematite concentrate. Simultaneously, it controls the iron grade of tailings to below 11.00%, significantly reducing tailings disposal costs and storage pressure, thus forming a synergistic effect of "quality improvement, efficiency enhancement, and cost reduction." This provides replicable and scalable technical support for the high-quality and sustainable development of similar mines.