297 results about "Phosphorite" patented technology

The embodiment of the invention discloses a mineral resource exploration data analysis method and device based on three-dimensional space modeling. The method comprises the steps that back-flushing pushing-covering structure feature information is extracted through structure interface occurrence measurement, lithology combination analysis and structure movement trace recognition and converted into geologic structure feature parameters; stratigraphic age data and lithology distribution information are integrated, and a three-dimensional stratigraphic model is constructed with a stratigraphic superposition relation as a constraint; geophysical data are imported to extract geophysical response characteristics of stratums with different depths, and lithologic boundary correction is combined to obtain deep fracture characteristic parameters; sedimentary system division is carried out on lithofacies paleogeographic information, and deep fracture characteristic parameters are fused to establish a fracture system three-dimensional model; the multi-feature association relationship is identified, the ore body prediction model is established, the spatial data is input to obtain the three-dimensional visual prediction result of the hidden ore body spatial distribution, and the exploration efficiency and accuracy in the deep phosphorite exploration process are improved.

The invention relates to the technical field of mineral processing visual detection, and discloses a visual analysis system for detecting the grade of a phosphorite flotation froth layer. The system comprises an image acquisition and decomposition module, a parallel feature extraction module, a dynamic feature fusion module, a foam evolution analysis module and a grade decision output module. The system performs multi-scale decomposition on a foam image, extracts physical and semantic features in parallel, constructs a dynamic fusion network based on bidirectional mapping to perform iterative interaction, and generates a multi-modal feature descriptor. Therefore, self-organizing growth of a foam evolution graph is driven, an evolution track of a key foam primitive is positioned and tracked, a foam grade state vector is formed, and finally, a regulation and control decision is output in combination with external control parameters. According to the system, deep fusion of physical and semantic features and deep analysis of the foam dynamic evolution process are achieved, the accuracy and predictability of foam grade state sensing are improved, and an effective means is provided for accurate control over the flotation process.

The invention relates to the technical field of phosphoric acid production, in particular to an intelligent optimization management method for phosphoric acid production process parameters. Obtaining adaptive window ranges at different moments according to data change characteristics of the phosphoric acid concentration sequence; obtaining a phosphoric acid production benefit value according to the phosphoric acid concentration in the self-adaptive window range; obtaining a benefit reference value according to the phosphoric acid production benefit value in the historical batch production process; obtaining a benefit comparison value according to the phosphoric acid production benefit value at the current moment and a benefit reference value; judging whether the production process is adjusted according to the benefit contrast value; obtaining a parameter deviation coefficient according to the difference characteristic of the sulfuric acid concentration of the production process corresponding to the benefit reference value and the current production process; and according to the parameter deviation coefficient and the benefit contrast value, obtaining a phosphorite putting amount difference coefficient. According to the parameter deviation coefficient, the phosphorite feeding amount difference coefficient and the benefit contrast value, the sulfuric acid concentration or the phosphorite feeding amount at the current moment is iteratively adjusted, and the quality of the phosphoric acid production process is improved.

The invention discloses a deep niobium phosphate ore positioning physical and chemical exploration method based on multi-method cooperation, and belongs to the technical field of geological mineral exploration. According to the method, a three-stage exploration system of region optimization, target region delineation and fine verification is constructed, multi-parameter cooperation of a magnetic method, an electromagnetic method, an induced polarization method, a three-component magnetic logging method and a geochemical method is combined, and each step is constrained by a basic rock-niobium phosphorite metallogenic model. An ore prospecting mark is determined through regional geological background analysis and metallogenic model construction, a metallogenic prospective region is delineated through regional optimization, a specific target region is delineated and locked, engineering verification is carried out through fine verification, and finally, a result is integrated to estimate the resource quantity. According to the method, the multiplicity of solutions of a single method is effectively reduced, the positioning precision of the deep niobium phosphorite is improved, the exploration efficiency and the target area ore finding rate are improved, and the method is suitable for accurate exploration of the deep niobium phosphorite.

The invention relates to a phosphorite wet processing method, and belongs to the technical field of chemical engineering. The phosphorite wet processing method comprises the following steps: A, phosphorite acid leaching: carrying out acidolysis leaching on a phosphorite raw material, and carrying out solid-liquid separation to obtain wet-process phosphoric acid; b, removing metal ions from wet-process phosphoric acid; and C, wet-process phosphoric acid defluorination: extracting fluosilicic acid in wet-process phosphoric acid at 10-70 DEG C by adopting a wet-process phosphoric acid defluorination extraction agent, and carrying out phase splitting to obtain defluorinated purified phosphoric acid and an organic phase loaded with fluosilicate. According to the invention, high-value utilization of low-grade phosphorite resources is realized. According to the method, impurities can be fully removed, the loss rate of phosphoric acid is low, the purity of the finally obtained phosphate product reaches 97% or above, the product quality is high, and the requirements of different fields for high-quality phosphate can be met. The method is simple in process, low in energy consumption and low in cost.

The present application belongs to the field of phosphate mining, and particularly relates to a method for mining a steeply inclined phosphate deposit without leaving a top and bottom pillar; the method comprises the following steps: dividing the phosphate layer in a mining section into several stages from bottom to top along the inclination, constructing a stage transport main in the lower part of each stage, and using the stage transport main of the previous stage as the stage auxiliary transport main of the next stage without leaving a bottom pillar and a top pillar; constructing an air return crosscut in the upper part of the uppermost stage from the air shaft, and then excavating an air return shaft from the air return crosscut downward along the inclination of the phosphate layer to connect with the stage auxiliary transport main and the stage transport main; arranging strip blocks along the strike on both wings of the stage to perform skip mining, first mining the odd strip blocks and filling them, and then mining the even strip blocks, the size of the strip blocks being determined according to the strength of the roof and floor, and no inter-pillar being left between the strip blocks; and thus mining all the stages from bottom to top. The present application greatly reduces the leaving of pillars and improves the resource recovery rate of one stoping.

The present application belongs to the field of phosphorite deposit mining technology, and particularly relates to a method for recovering a phosphorite layer bottom pillar under a filling body, which comprises arranging a segmented transport roadway in a sandwich in the top and bottom surface of the bottom pillar to reduce the construction engineering quantity of the rock drilling roadway and the ore roadway; first constructing a filling roadway intersecting on both sides of the segmented transport roadway, filling the filling body roadway with high-strength filling material, and then constructing the segmented transport roadway in the filling roadway, so that the segmented transport roadway is finally topped and bottomed with the sandwich rock, and both sides of the segmented transport roadway are high-strength filling bodies, which greatly improves the strength of the segmented transport roadway and reduces the influence of ore mining. Further, the present application proposes an invention point of leaving a permanent ore pillar in the ore body on one side of the sandwich bottom plate to improve the safety of the segmented transport roadway and the ore room mining; in order to further improve the safety of the ore room mining, the present application first proposes an ore room adopting an eight-character-shaped stope structure.

The invention discloses a ternary solid waste gelling system mine cemented filling material, a preparation method and application, phosphogypsum and water-quenched slag powder are used as main gelling components, carbide slag is used as an exciting agent, and phosphate tailings and phosphorus tail mud are used as filling body aggregate to form the high-content phosphogypsum ternary solid waste gelling system mine cemented filling material. Wherein the ternary solid waste gel system comprises the following components in percentage by weight: 10-18% of carbide slag, 36-54% of ardealite and 36-54% of water-quenched slag powder, and the ratio of ardealite / (ardealite + water-quenched slag powder) is 0.4-0.6. The mine cemented filling material disclosed by the invention is prepared by taking solid wastes of industrial byproducts of a phosphorite mountain and the periphery of the phosphorite mountain as main raw materials, and the mechanical property of the prepared filling slurry after solidification needs to meet an engineering filling strength index, so that efficient resource utilization of a large amount of industrial solid wastes for phosphorite resource development can be realized; good mechanical properties and remarkable economic and environmental benefits are achieved.

The invention relates to a high-temperature acidolysis reaction defluorination method, and belongs to the technical field of phosphorus chemical resource recycling. The technical problem to be solved by the invention is to provide a high-temperature acidolysis reaction defluorination method which is simple to operate and high in defluorination rate. According to the method, phosphorite powder / white fertilizer is subjected to high-temperature acidolysis, fluoride in the phosphorite powder / white fertilizer reacts with strong acid, fluorine is separated from a reaction system in a gas form, and hydrofluoric acid is obtained through condensation. The method is simple, is simple and convenient to operate, and is easy to realize technologized large-scale production. Meanwhile, due to the destructive effect of the strong acid on the lattice structure of the phosphorus-calcium compound, citrate-soluble phosphorus can be converted into soluble phosphate, subsequent phosphorus recovery is facilitated, comprehensive utilization of phosphorite and elimination of white fertilizer output are achieved, meanwhile, the problems of material accumulation and resource waste of enterprises are solved, and the method conforms to the circular economy concept of green development.

The invention discloses artificial soil based on manganese slag, red mud and ardealite. The artificial soil is mainly prepared from a manganese slag-red mud-ardealite mixed matrix and a modifier, the weight ratio of the manganese slag to the red mud to the ardealite in the manganese slag-red mud-ardealite mixed matrix is (0.4-1.6): (0.1-0.5): (0.5-0.9); the modifier comprises calcium oxide, and further comprises rice straw, biochar, zeolite or a combination thereof, and the modifier accounts for 1-15% of the weight of the artificial soil. Accordingly, a corresponding preparation method is also established. According to the method, the three solid wastes are mixed according to the characteristics, so that specific pollutants such as ammonia nitrogen, phosphorus, fluorine and Mn < 2 + > can be fixed, the reduction of heavy metals is realized, the nutrients beneficial to plant growth are reserved, the artificial soil with rich nutrients is synchronously reconstructed, the qualitative change from waste residues to resources is realized, the process is simple, and the effect is good. The obtained artificial soil can be used for greening planting, supplementing manganese ore, aluminum ore and phosphorite surrounding soil deficiency areas, and solving the problems of no soil, ploughability and ecological restoration of mining areas.

The invention discloses a method for smelting yellow phosphorus and alloy by using high-magnesium low-grade phosphorite, which comprises the following steps of: proportioning the high-magnesium low-grade phosphorite, a calcium flux, a siliceous flux, iron ore and a carbonaceous reducing agent, and carrying out reduction smelting treatment, so that part of apatite is reduced to generate yellow phosphorus steam, and part of phosphorus steam and reduced iron are chemically combined to form the alloy; calcium oxide, magnesium oxide, silicon oxide and aluminum oxide form low-melting-point smelting slag, and activated slag is obtained through water quenching. The method can provide technical reference for efficient resource utilization of low-grade phosphorite, especially high-magnesium and high-iron type low-grade phosphorite, three products of high-quality yellow phosphorus, high-added-value ferrophosphorus and activated smelting slag are obtained at the same time, and no new solid waste is generated in the process.

The invention discloses a phosphorite mining method which comprises the following steps: constructing and cutting an uphill along a top plate of an ore body from a lower layered gate way to an upper layered gate way, and supporting by adopting a resin anchor rod, a reinforcing mesh and a mining anchor cable; cutting groove construction is conducted, medium-length holes are formed in the lower layered gate way, explosives are loaded in the medium-length holes to conduct blasting layer by layer, a cut uphill bottom plate is continuously lowered till an ore body bottom plate is reached, and the cutting grooves are formed; fan-shaped medium-length holes are constructed in the lower layered gate way, a plurality of rows of fan-shaped medium-length holes are formed in the vertical direction, a plurality of holes are formed in each row of fan-shaped medium-length holes in the vertical direction, blasting is conducted with the cutting groove as a vertical free face, and the fan-shaped medium-length holes are blasted in batches; and charging powder in the lower layered roadway, and after blasting, entering a stope by adopting a remote control forklift for ore removal. The vertical free surface blasting technology is adopted for blasting the medium-length holes in batches, and the method has the advantages that the top plate operation safety is improved, the mining period is shortened, and the ore recovery rate is increased.

The present application belongs to the field of phosphate ore filling mining, and particularly relates to a phosphate ore deposit bottom pillar and ore block coordinated stage empty field subsequent filling mining method, which comprises the following steps: dividing the ore bed into a plurality of ore blocks along the strike of the ore bed, wherein the ore block comprises an ore room and a bottom pillar; constructing a roadway for transportation and ventilation; first mining the ore bed with a smaller rock mass strength coefficient and filling; retaining or blasting the interlayer; mining the ore bed with a larger rock mass strength coefficient and filling; and mining the ore bed in the bottom pillar of the previous middle section. The present application does not need to fill the empty area formed by the bottom pillar recovery, can reduce the filling process and filling material, reduce the filling cost and construction process, and improve the mining efficiency. The present application can realize the full mining of the ore bed, does not leave the top pillar, and recovers the bottom pillar without filling, so that the ore recovery rate is close to 100%, and good economic benefits can be achieved.

The invention discloses a method for recovering valuable elements in phosphorite step by step through gradient acid leaching, which comprises the following steps: firstly, mixing high-magnesium phosphorite and high-silicon phosphorite in proportion for ore blending, and carrying out crushing, grading and ball milling until the particle size is less than or equal to 200 meshes; then, adopting a gradient acid leaching process: (1) leaching with low-concentration inorganic acid (1-3wt%), and preferentially and selectively removing dolomite and calcite to obtain phosphate concentrate and leachate rich in calcium and magnesium; (2) leaching the phosphate concentrate by using medium-concentration inorganic acid (5-8wt%), and dissolving the phosphate concentrate to obtain a phosphate concentrate leachate and residues mainly containing iron, aluminum and silicon; and (3) leaching the residues by using high-concentration inorganic acid (30-40wt%) to obtain silicon-rich residues and a leaching solution rich in iron and aluminum. (4) neutralizing and carbonizing the calcium-magnesium leaching solution, and respectively precipitating and recovering magnesium hydroxide and calcium carbonate; (5) carrying out fractional precipitation on the phosphate concentrate leachate to obtain rare earth enrichment and calcium hydrogen phosphate; (6) carrying out alkali dissolution and carbonization reaction on the silicon-rich slag to prepare high-purity white carbon black; and (7) carrying out iron powder reduction, neutralization aluminum removal and oxidation iron precipitation on the iron and aluminum lixivium to prepare the battery-grade iron phosphate. The method is simple and convenient to operate, energy-saving and environment-friendly, various valuable elements in the phosphorite are efficiently recycled, and the economic added value of phosphorite resources is increased.

The invention discloses a long-acting stable filling agent for phosphorite mining and a preparation method and application thereof, the long-acting stable filling agent takes cement, slag powder, phosphogypsum and fly ash as matrix components, and is supplemented with additives such as a nano modified liquid, a retarder and an early strength agent. The 3d compressive strength reaches 4.6-5.5 MPa, the 28d compressive strength reaches 13.5-15.5 MPa, the 90d strength retention rate in a simulated acid environment is larger than or equal to 84%, the volume shrinkage rate is smaller than or equal to 0.5%, and the early strength and the excellent long-term acid-resistant stability are both high. Through a synergistic effect of a nano-micron composite structure, pores are filled with nano particles and secondary hydration is promoted, basalt fibers are bridged to resist cracking, and nano montmorillonite blocks acid etching, so that unification of high early strength and long-acting acid resistance is realized. The material is simple and convenient in preparation process, can be efficiently used for mining and filling of phosphorite mountains, and meets the requirements of rapid support and long-term acid medium erosion resistance.

The invention belongs to the field of phosphorite mountain mining, and relates to a mining method suitable for a gently inclined thick and large phosphorite body containing a soft interlayer, which comprises the following steps: carrying out stope division and pseudo-inclined strip arrangement, dividing the ore body into manageable mining units, and optimizing a stoping sequence and a filling strategy; roof pre-cutting construction and roof supporting are conducted, a top ore bed is stoped and supported, and the stability of a roof is controlled; stoping the chambers, extracting the ores in the chambers, and adopting different stoping modes according to the thicknesses of the clamped ores, so as to maximize the ore recovery rate and minimize the loss; clamping stone processing and transferring are conducted, processing is conducted according to the thickness of the clamping stone, the clamping stone is removed to improve the ore grade, or the clamping stone is reserved; a filling retaining wall is constructed, and a retaining wall is arranged in the mined-out area after stoping; and subsequent filling and pillar stoping are conducted, the goaf is filled with filling materials, surrounding rock is supported, and pillars are stoped to achieve comprehensive recovery of resources. The problems that a traditional method is high in depletion rate, difficult in roof control and poor in adaptability are solved, and the mine production efficiency is remarkably improved.

The utility model relates to the technical field of phosphorite treatment, in particular to a device and system for preparing ammonium phosphate and byproduct nitrophosphate fertilizer by decomposing phosphorite with nitric acid. The device comprises an acidolysis tank, the acidolysis tank is connected to a first separator, the first separator is connected to a first crystallizer, the first crystallizer is connected to a second separator, the second separator is connected to a decalcification tank, the decalcification tank is connected to a denitration tank, and the denitration tank is connected to a second crystallizer. The denitration tank is respectively connected to the repulping tank and the purification equipment; the re-pulping tank is connected to a neutralizing tank, and the neutralizing tank is connected to a first concentrator; and the purification equipment is connected to the second concentrator. According to the device disclosed by the invention, the mother liquor generated by the acidolysis tank is deeply processed to prepare monoammonium phosphate and purified phosphoric acid, meanwhile, a byproduct white fertilizer can be processed into a phosphorus (potassium) nitrate fertilizer, and a byproduct white gypsum is obtained.

The invention discloses a microbial carrier and a preparation method thereof, a composite microbial agent and a preparation method and application thereof, the microbial carrier provided by the invention takes a cross-linked body formed by cross-linking a phosphorite thermal activation product and a cross-linking agent as the microbial carrier, and the phosphorite thermal activation product is obtained by carrying out thermal activation, water quenching and grinding on phosphorite. A phosphorite thermal activation product obtained after phosphorite is subjected to thermal activation treatment has a porous structure, calcium, magnesium, silicon and slow-release phosphorus in the phosphorite thermal activation product are easily absorbed and utilized by functional microorganisms, a three-dimensional network porous structure is obtained after the phosphorite thermal activation product is cross-linked with a cross-linking agent, the loading rate of the functional microorganisms can be increased, and the utilization rate of the functional microorganisms is increased. In addition, good biocompatibility of the microbial carrier provides a suitable growth environment for functional microorganisms, survival and reproduction of the microorganisms in the gel are facilitated, and good application value and application effect are achieved.

The invention discloses a method for improving phosphorite reaction activity and fluorine resource recovery rate. The method mainly aims at medium-low-grade collophanite after flotation, and comprises the following steps: firstly, pretreating phosphorite by using fluosilicic acid to prepare high-concentration phosphorite slurry; carrying out premixing reaction on the phosphoric ore pulp and phosphoric acid, and then carrying out crystallization reaction with sulfuric acid with a certain concentration; a flash cooling and flue gas washing system is arranged in each reaction area, so that escape and recovery of fluorine are enhanced; and after the reaction is finished, filtering and washing to obtain phosphoric acid and phosphogypsum. The phosphorite is pretreated by using low-concentration fluosilicic acid recovered in a phosphoric acid concentration section, the phosphorite pre-decomposition pH is adjusted by using fluosilicic acid, carbonate, silicate and quartz impurities in the phosphorite are preferentially dissolved, and micro-channels are formed on the surfaces of phosphorite particles, so that the subsequent use amounts of phosphoric acid and sulfuric acid are reduced, and the content of aluminum phosphate ions in the product is reduced; the phosphorite acidolysis efficiency is improved. Meanwhile, introduction of fluosilicate accelerates escape of fluorine in phosphorite, and the fluorine yield of the system is increased.

The invention belongs to the technical field of phosphorite beneficiation, and relates to a collophanite re-flotation combined selection and middle grading quality-grading flotation method. According to the technical scheme, the method comprises the steps that phosphoric ore pulp is fed into a spiral chute set to be reselected, reselected products including reselected concentrate and reselected tailings are obtained, then the reselected concentrate obtained through separation is fed into a flotation dealumination procedure, reselected concentrate and tailings are obtained, the tailings obtained after reselected flotation are fed into a grading and grading procedure, and tailings 1 and middlings are obtained. And then the middlings and the spiral chute heavy tailings are combined and enter a heavy tailing flotation dealumination procedure, and heavy tailing concentrates and tailings 2 are obtained. The process has the advantages that the mixed heavy, fine and heavy tailings can be effectively classified in the industrial production, so that the flotation comprehensive recovery rate in the industrial production is effectively improved, and the flotation auxiliary material cost is reduced.

The invention relates to a combined inhibitor for reverse flotation magnesium removal of medium-low grade phosphorite and application thereof. The combined inhibitor comprises sodium sulfate, 1, 2, 4-butanetricarboxylic acid and sulfuric acid. The application method comprises the following steps: grinding raw ore, adding water and mixing to obtain ore pulp; the pH of the ore pulp is adjusted, then the combined inhibitor is sequentially added and mixed, then a collecting agent is added and mixed, flotation is conducted, and phosphate concentrate and phosphate tailings are obtained; the flotation process comprises one-time rough flotation, at least one-time fine flotation and at least one-time scavenging; the combined inhibitor provided by the invention is good in calcium and magnesium interference resistance and high in selectivity, the dosage of sulfuric acid is remarkably reduced, the pH value of ore pulp is increased, magnesian gangue in phosphorite is effectively removed through the synergistic effect of all the components, the grade of phosphate concentrate is increased, meanwhile, the recovery rate is high, and the combined inhibitor has good industrial application prospects.

The invention provides a preparation method of an amphoteric collecting agent and application of the amphoteric collecting agent in direct and reverse flotation of medium-low-grade phosphorite, and belongs to the technical field of mineral processing engineering. According to the amphoteric collecting agent, R can regulate and control hydrophobic chains, hydrophobic adsorption energy and molecular dispersity are optimally balanced, then the surface activity and dispersity of the amphoteric collecting agent are improved, and efficient dispersion at the temperature of 25 DEG C is achieved; the quaternary ammonium salt structure has the advantages that the cation characteristic of the quaternary ammonium salt structure is kept stable in the whole pH range and is not influenced by the environmental pH, so that a foundation is provided for effectively playing a cation collecting role in two distinct pH environments of direct flotation and reverse flotation; the problem that a traditional amine collecting agent loses positive charges under the alkaline condition and loses efficacy is solved.

The application provides a phosphate ore sorting method, an electronic device and a medium. In a preprocessing stage, a high-energy image obtained from raw ore is registered with a low-energy image as a reference, a difference image representing a gray difference is obtained from the registered high-energy image and the low-energy image, and the low-energy image, the registered high-energy image and the difference image are fused in three channels to obtain a pseudo-color image. In an intelligent identification stage, the pseudo-color image is taken as input, and a target detection model based on deep learning is used for processing, so that accurate and efficient identification of phosphate ore in the raw ore is realized.

The application is a beneficiation method for removing iron and aluminum sesquioxide from high-grade collophanite, and belongs to the technical field of mineral processing. The material obtained by crushing, superfine grinding and grading of raw ore is fed into a heavy separation operation to obtain a heavy separation concentrate and a heavy separation tailing; the heavy separation concentrate is fed into a reverse flotation magnesium removal operation buffer tank, and the heavy separation tailing is thickened, re-ground, classified, and then subjected to positive flotation desliming and positive flotation desilication, and the obtained concentrate is fed into the reverse flotation magnesium removal operation; three backwater pools are built to store positive flotation desilication backwater, reverse flotation magnesium removal backwater and heavy separation operation backwater respectively. The method mainly aims at high-grade high-sesquioxide calcareous collophanite, adopts heavy and float combined separation, divides the raw ore into a heavy separation concentrate and a heavy separation tailing through a heavy separation device, and subjects the heavy separation tailing to positive and reverse flotation to obtain a heavy tailing flotation concentrate. The separation process fully utilizes the advantages of positive and reverse flotation and heavy separation, the process flow is stable, the separation effect is good, high-quality phosphorus concentrate is realized, and low-quality phosphorus concentrate can be used.

This invention relates to the field of fertilizer production technology, specifically to a segmented ripening preparation process for low-free-acid, high-water-soluble superphosphate; the process includes the following steps: feeding phosphate rock powder into a ball mill for grinding to a particle size ≤120 mesh, preparing 93%±0.5% industrial sulfuric acid; adding phosphate rock powder at a molar ratio of available P2O5 to sulfuric acid of 1:1.05~1:1.07, adding 0.3%~0.5% (by weight of phosphate rock powder) of a modifying agent, and reacting at 65~70℃ for 40~50 minutes. In the later stage of the reaction, low-pressure steam of 0.2 MPa is introduced; staged maturation is carried out, first in a closed chamber at 55~60℃ for 24 hours, and then in a ventilated chamber at 45~50℃ and a wind speed of 0.8~1.0 m / s for 48 hours; granulation and screening are carried out, with the granulation drum rotating at 14~16 r / min and tilted at an angle of 3°~5°; through the above methods, the problems of high free acid, low proportion of water-soluble phosphorus and insufficient production efficiency in traditional processes are solved, and the product quality and production capacity are synergistically improved.

The invention relates to the field of phosphoric acid production, and particularly discloses an improved nitric acid method crude phosphoric acid production process and a denitration concentration system. The production process comprises the following steps: decomposing phosphorite with dilute nitric acid, freezing and crystallizing the obtained acidolysis solution, filtering, and adding concentrated sulfuric acid to obtain a mixed acid solution containing phosphoric acid and nitric acid; and introducing the mixed acid liquid into a first-effect evaporator and a second-effect evaporator for double-effect evaporation, and distilling in a rectifying tower to obtain a crude phosphoric acid product. According to the application, mixed acid is subjected to denitration concentration by adopting a downstream double-effect evaporation technology, by virtue of a pressure-temperature double-gradient design and in combination with a rectifying tower, staged denitration is realized by utilizing the pressure dependence of the volatility of nitric acid, and primary denitration and energy supply are realized by adopting a high-pressure and high-temperature evaporation section as a first-effect evaporation section; the second-effect evaporation is a vacuum low-temperature evaporation section, deep denitration and acid enrichment are achieved, and the concentration of nitric acid enriched in the low-temperature section reaches 55 wt%. The concentration of phosphoric acid in the finally obtained product is more than or equal to 75wt%, and the residual nitric acid is less than or equal to 0.5

The invention discloses a dechlorination method of a wet-process phosphoric acid process, and belongs to the technical field of dechlorination of wet-process phosphoric acid. The method comprises the following steps: adding ground phosphorite into a reaction tank A, carrying out decomposition reaction on the phosphorite and high-temperature slurry to obtain slurry a, pumping the slurry a into a reaction tank B, adding concentrated sulfuric acid and a sodium persulfate solution, activating sodium persulfate in the inherent high temperature, strong acid and Fe2 environment, carrying out oxidation dechlorination reaction, and carrying out solid-liquid separation to obtain low-chlorine phosphoric acid and phosphogypsum; finally, the reaction tank B is connected with a tail gas washing system, water is used for circulating washing, then alkali liquor is used for countercurrent washing, and the pollution discharge standard is met. The oxidation dechlorination process is integrated in the wet-process phosphoric acid production process for the first time, chloride ions are efficiently oxidized into chlorine to be removed by utilizing the strong oxidizing property of sodium persulfate, the dechlorination rate can reach 95% or above, the chlorine content in phosphoric acid is remarkably reduced, equipment corrosion is relieved, the product quality is improved, and the method is simple in process, low in energy consumption, low in cost, green, environmentally friendly and suitable for industrial production. The method is suitable for industrial application.

The invention relates to a pre-separation process for reducing the phosphorus loss rate of micro-fine particle collophanite. According to the technical scheme, the method comprises the steps that phosphoric ore pulp is introduced into pre-separation operation, an emulsifying collecting agent and a foaming agent are added into the phosphoric ore pulp, pre-separation is conducted, an in-tank product I and a foam product I are obtained, and the foam product I is tailings I; the product I in the tank is introduced into reverse flotation roughing operation, a dealumination collecting agent is added into the product I in the tank for roughing, and a product II in the tank and a foam product II are obtained; and the foam product II is introduced into scavenging operation, a dealumination collecting agent is added into the product I in the tank for scavenging and roughing, a product III in the tank and a foam product III are obtained, the foam product III is tailings II, and the product III in the tank and the product II in the tank are combined into phosphate concentrate. According to the method, pre-separation is conducted on the micro-fine-particle collophanite, the problem that the micro-fine-particle collophanite is poor in separation performance is effectively solved, the grade of tailings can be greatly reduced, the phosphorus loss rate of micro-fine-particle collophanite separation is reduced, meanwhile, scavenged middlings do not enter a circulation and are directly combined into phosphorus concentrate, the phosphorus concentrate yield is further increased, the whole technological process is an open circuit, and the method is suitable for industrial production. The process is short and easy to control, and industrialization can be realized.

The invention discloses a collophanite dry sorting method based on combination of color sorting and a dense medium fluidized bed. According to the method, aiming at the defects of high environmental protection risk and insufficient single color sorting precision of existing wet sorting, efficient quality improvement of medium-low-grade collophanite is realized through a synergistic process of color sorting classification and dry-method dense medium fluidized bed enrichment: firstly, raw ore is crushed, concentrate, middling and tailings are obtained through two-stage color sorting classification, the concentrate is subjected to secondary color sorting, and the concentrate is subjected to secondary color sorting; the crushing size fraction is adjusted according to the content of phosphorus pentoxide, then an iron powder dense medium matched with the mineral particle size is adopted, and accurate separation is achieved through differentiated fluidization separation density. The whole process is free of water and chemical agents, the average grade of the concentrate reaches 20% or above, the phosphorus recovery rate is 80% or above, the environment-friendly requirements of ecological sensitive areas such as water sources are met, medium-low-grade resources can be fully utilized, the production cost is reduced, and the adaptability is wide.

The invention discloses a method for preparing yellow phosphorus from refractory siliceous phosphorite, and solves the technical problem of how to improve the suitability of refractory siliceous phosphorite powder. Comprising the following steps: a) adding a pretreatment adhesive into refractory siliceous ground phosphate rock, then carrying out wet grinding pretreatment to obtain wet fine powder, and then carrying out first heating treatment on the wet fine powder to obtain dried pretreated mineral powder; b) mixing the pretreated mineral powder with a forming adhesive and water to obtain a mixed material, and then carrying out compression molding on the mixed material to obtain phosphate rock green pellets; c) carrying out second heating treatment on the green phosphorite pellets to obtain dried and solidified phosphorite pellets; d) the phosphorite pellets, a carbonaceous reducing agent and a siliceous flux are mixed and then fed into an electric furnace to be smelted, and furnace gas containing yellow phosphorus steam is generated; e) dedusting and purifying the furnace gas, and condensing the dedusted and purified furnace gas so as to recover yellow phosphorus and produce tail gas rich in carbon monoxide; wherein the pretreatment of the adhesive and the wet grinding pretreatment are cooperated.