340results about "Phosphates" patented technology

The invention discloses a lithium-manganese-rich positive electrode material as well as a surface modification method and application thereof, and belongs to the technical field of preparation of battery positive electrode materials. The preparation method comprises the following specific processes: (1) stirring, dispersing and dissolving nickel salt, cobalt salt and manganese salt, and then adding a precipitator and a complexing agent to prepare a lithium-rich manganese-based precursor; (2) mixing the lithium-rich manganese-based precursor, a lithium source and fused salt, and calcining to obtain a single-crystal lithium-rich manganese-based oxide material; (3) stirring and reacting the single crystal lithium-rich manganese-based oxide material and a surface modifier through a wet chemical method to prepare coated precursor powder; and (4) grinding and calcining the coated precursor powder prepared in the step (3) to prepare the surface-modified lithium-manganese-rich positive electrode material. The preparation method provided by the invention is low in raw material cost, the in-situ surface modification adopts the combination of a wet chemical method and heat treatment, the operation is simple, the production environment requirement is low, the first coulombic efficiency and the cycling stability of the lithium-rich manganese-based positive electrode material are effectively improved, and the preparation method is suitable for large-scale batch production.

The invention provides a microporous cathode electrochemical induced crystallization precipitation system and application thereof.The system comprises an anode chamber and a cathode chamber, an anode plate is a Ru / Ir mesh electrode, and a cathode plate is a stainless steel mesh cathode with the high mesh number of 100-300 meshs.According to the microporous cathode electrochemical induced crystallization precipitation system, the mesh cathode with the high mesh number is used for replacing a traditional anion exchange membrane; the high-mesh-number net-shaped cathode prevents hydrogen ions generated by the anode from migrating to the cathode chamber, the high-pH environment of the cathode chamber is guaranteed, the pH of the cathode chamber reaches up to 10.90, the phosphorus recovery efficiency reaches 93.14%, meanwhile, the cost is greatly reduced and is only 1.25% of that of an ion exchange membrane, needle-shaped nano-hydroxyapatite serves as an additional seed crystal, the needle-shaped nano-hydroxyapatite (ANHD) is put into the cathode chamber, and the yield of phosphorus is greatly increased. The seed crystal effect of ANHD is fully exerted, and the recovery efficiency of orthophosphorus is improved by 24.40%.

The invention discloses thixotropic pure inorganic gel with adjustable physical properties as well as a preparation method and application of the thixotropic pure inorganic gel. The pure inorganic gel comprises loosely assembled nanorod assemblies and a solution for dispersing the loosely assembled nanorod assemblies, the nanorod assembly comprises an inorganic one-dimensional nanorod and anions capable of participating in the assembly of the inorganic one-dimensional nanorod; the inorganic one-dimensional nanorod at least contains rare earth metal elements. Compared with inorganic gel materials with other morphologies, the inorganic thixotropic gel disclosed by the invention can generate physical structure change through self-assembly of the inorganic one-dimensional nanorods, and has a relatively good physical property adjustment basis. And secondly, the inorganic one-dimensional nanorod can form an assembly through ions without additionally adding a surface modification reagent, the change of physical properties can be realized without replacing ligands, and the inorganic one-dimensional nanorod has extremely high advantages in various applications.

The present application relates to the technical field of battery preparation, and specifically discloses a production process of ammonium dihydrogen phosphate for batteries, which comprises eleven process steps of dearsenicating, decolorizing, aerating, filtering, decolorizing after preheating, defluorinating, neutralizing, circulating, crystallizing, separating, drying and packaging wet-process phosphoric acid to produce battery-grade ammonium dihydrogen phosphate. In the dearsenicating, decolorizing and defluorinating processes, only one filtration using a membrane filter is required after decolorizing, and there is no need to add a filter in each step, so the process flow is not shortened, the production efficiency of battery-grade ammonium dihydrogen phosphate is improved, and the reduction of filtering equipment reduces the production input cost.

In one aspect, a lithium manganese iron phosphate material includes a core, and a material of the core is represented by a general formula of LixMgyMnzFeaAlbPO4, where x is ranged from 1.008 to 1.05, y is ranged from 0 to 0.006, z is ranged from 0.4 to 0.6, a is ranged from 0.388 to 0.6, and b is ranged from 0 to 0.012.

Aerogel materials, aerogel composites, and the like may be improved by the addition of opacifiers to reduce the radiative component of heat transfer. Such aerogel materials, aerogel composites, and the like may also be treated to impart or improve hydrophobicity. Such aerogel materials and methods of manufacturing the same are described.

The invention relates to the technical field of drying equipment, in particular to a drying and cooling device for monoammonium phosphate production, which comprises a base, a drying cylinder and a feeding shell are mounted at the upper end of the base, the feeding shell is mounted at the upper end of the drying cylinder, a drying assembly is arranged in the drying cylinder, and the drying assembly comprises a material changing mechanism and a drying mechanism. The material changing mechanism comprises a rotating roller, storage grooves and discharging openings, the rotating roller is rotationally connected into the drying cylinder, the multiple storage grooves are all formed in the circumferential surface of the rotating roller, the multiple discharging openings are all formed in the front end of the rotating roller, and a discharging opening is formed in the rear end of the drying cylinder; under the action of the drying assembly, a small amount of monoammonium phosphate slurry can be continuously stored for multiple times, and the monoammonium phosphate slurry is continuously discharged after being dried, so that feeding and discharging are consistent when monoammonium phosphate is dried, and the drying efficiency of the monoammonium phosphate slurry is improved.

The present invention relates to the technical field of lithium-ion batteries. Disclosed are a lithium manganese iron phosphate positive electrode material and a preparation method therefor. The preparation method comprises: uniformly mixing raw materials with a solvent to obtain a primary mixture, wherein the raw materials include a phosphorus-containing compound, a manganese-containing compound, an iron-containing compound, a lithium-containing compound, and a carbon-containing compound; performing primary pretreatment and primary sintering on the primary mixture to obtain a primary sintered material; uniformly mixing the primary sintered material, an additive, and a solvent to obtain a secondary mixture, wherein the additive contains the element phosphorus; performing secondary pretreatment and secondary sintering on the secondary mixture to obtain a secondary sintered material, wherein the secondary sintering enables the phosphorus in the additive to be distributed on the surface of particles of the secondary sintered material to form a phosphorus-rich shell layer; and performing post-treatment on the secondary sintered material to obtain the lithium manganese iron phosphate positive electrode material. The present invention can reduce the powder resistivity of the positive electrode material, so that the attenuation rate of a voltage platform in the cycling process is slowed down, and the cycle life of the lithium manganese iron phosphate positive electrode material is prolonged.

The invention belongs to the field of chemical industry, and discloses a high-performance monoammonium phosphate production method, which comprises: S1, raw material pretreatment: carrying out pretreatment on phosphate ore and ammonia gas to remove impurities; the pretreated phosphate ore reacts with sulfuric acid to generate phosphoric acid, then the phosphoric acid reacts with ammonia gas to generate monoammonium phosphate, the reaction temperature of the phosphate ore and the sulfuric acid is 80-100 DEG C, the reaction time is 2-6 hours, and the concentration of the phosphoric acid is 0.2 mol.L <-1 >-2 mol.L <-1 >; s3, crystallization: cooling and crystallizing to obtain monoammonium phosphate crystals; s4, separation: separating the monoammonium phosphate crystals from the mother liquor; s5, drying: carrying out drying treatment on the separated monoammonium phosphate crystals; and S6, packaging: packaging the dried monoammonium phosphate to obtain a finished product. According to the invention, the purity and production efficiency of monoammonium phosphate are greatly improved, the production process flow is reduced, and the energy consumption and environmental pollution are reduced.

The invention belongs to the technical field of lithium ion battery materials, and discloses a composite modified negative electrode material and a preparation method and application thereof, the composite modified negative electrode material comprises a Mn2Si (P2O7) 2 nanometer material, nanometer silicon and layered graphite, and the Mn2Si (P2O7) 2 nanometer material, the nanometer silicon and the layered graphite material are uniformly distributed. The composite modified negative electrode material has good structural stability, and silicon element and nano silicon in pyrophosphate silicate in the negative electrode material can form Si-Si covalent bonds, so that the adhesive force of a surface composite layer of the negative electrode material can be greatly improved, polymer of the nano silicon can be inhibited, the volume expansion of a silicon negative electrode can be relieved, and the cycle performance of the battery can be improved.

The utility model discloses a diammonium phosphate granulating and drying system which comprises a grid plate, a grid plate is horizontally fixed at the lower part of the granulator, and a plurality of strip-shaped holes which are parallel to one another are formed in the grid plate; a plurality of sliding grooves are formed in the inner wall of the tail of the drying machine in the axial direction, a crushing base plate is inserted into each sliding groove in a sliding mode, the crushing base plates are fixedly connected with the drying machine through penetrating screws, and a plurality of crushing teeth are vertically fixed to the crushing base plates. The device has the advantages that caked materials granulated by the granulator are intercepted on the grid plate, and part of the caked materials are pushed out from the discharge door by the material pushing plate, so that the caked materials are cleaned; after the materials are dried by the drying machine, the materials are thrown up by the material raising plate and fall on the crushing teeth on the crushing base plate under the action of gravity, so that the primary crushing effect on the dried caked materials is achieved, the caked materials generated in the granulation process can be effectively crushed, and the normal production efficiency and the production quality are prevented from being influenced by material blockage.

The utility model relates to an ammonium phosphate evaporation and concentration system and belongs to the field of chemical engineering. The system comprises a concentrated ammonium phosphate pump, a concentrated ammonium phosphate storage tank, an I-effect evaporation chamber, an I-effect heater, an I-effect circulating pump, an I-effect charging pump, an II-effect evaporation chamber, an II-effect heater, an II-effect circulating pump, an II-effect charging pump, an III-effect evaporation chamber, an III-effect heater and an III-effect circulating pump. By adopting the system and the method, low-pressure saturated live steam is utilized to indirectly heat dilute ammonium phosphate to generate secondary steam and tertiary steam to continuously heat the dilute ammonium phosphate to produce concentrated ammonium phosphate. Compared with a two-effect evaporation concentration process flow which is widely used at present, the three-effect countercurrent evaporation concentration process flow saves energy by 47%. The utility model aims at saving energy, reducing consumption, reducing carbon emission of a production device and protecting the environment.

The invention discloses an organophosphorus degradation and synchronous recovery system based on a double-cathode induced electro-Fenton reaction. An induced iron electrode plate and an electrochemical assembly with double cathode plates are arranged in an electrolytic tank; the double cathode plates are a gas diffusion cathode plate and an iron reduction cathode plate; the gas diffusion cathode is used for reducing oxygen to generate hydrogen peroxide, the induction iron electrode releases ferrous ions under the action of an electric field, the ferrous ions and the hydrogen peroxide are subjected to a Fenton reaction, organic phosphorus is degraded into PO4 < 3->, Fenton reaction by-products Fe < 3 + > and PO4 < 3-> form iron phosphorus precipitates, and degradation of the organic phosphorus and synchronous recovery of orthophosphate are realized; excessive Fe < 3 + > is adsorbed by the iron reduction cathode and is further reduced into Fe < 2 + > which enters the solution again to participate in the Fenton reaction, so that the reaction efficiency is improved, and Fe < 3 + > / Fe < 2 + > circulation is promoted while slow release of iron is realized. The device is simple in structure, low in maintenance cost and high in operability, and the purpose of efficiently recycling phosphorus resources is achieved.

The invention relates to the technical field of phosphorus chemical industry, in particular to a method for preparing monoammonium phosphate from raffinate acid, which comprises the following steps: S1) uniformly mixing the raffinate acid with concentrated sulfuric acid, concentrating, and performing solid-liquid separation to obtain a concentrated solution; s2) dropwise adding a solvent into the concentrated solution for primary solvent purification; the solvent components are limited; s3) standing and splitting the light and heavy mixed phase obtained by purifying the primary solvent to obtain an acid-containing solvent phase; s4) mixing the acid-containing solvent phase with barium fluoride, carrying out a reaction, and carrying out solid-liquid separation to obtain a secondary purified acid-containing solvent and purified slag; s5) carrying out vacuum distillation on the secondary purified acid-containing solvent, and recovering the solvent to obtain a distillation kettle residual liquid which is purified acid; and S6) diluting the purified acid, then mixing the diluted purified acid with an ammonia-containing alkaline substance, carrying out a neutralization reaction, filtering after the reaction, and drying and granulating a filter cake to obtain the fire-fighting grade monoammonium phosphate product. The method provided by the invention has the advantages of high impurity removal rate, high phosphorus yield and high added value of the product, and can be used for preparing fire-fighting grade monoammonium phosphate.

The invention relates to the technical field of ammonium dihydrogen phosphate preparation, and discloses a high-purity ammonium dihydrogen phosphate crystallization device and a method thereof.The high-purity ammonium dihydrogen phosphate crystallization device comprises a first-stage crystallization system, a first-stage centrifugal separation system, a second-stage crystallization system and a second-stage centrifugal separation system which are connected in series. The primary crystallization system comprises a crystal elimination heater, a crystal elimination mixer, a bag filter and a DTB flash cooling crystallizer which are connected in sequence, and is used for primarily purifying a concentrated solution; the primary centrifugal separation system is used for separating primary crystals; the second-stage crystallization system comprises a crystal dissolving tank, an OSLO cooling crystallizer and the like, and deep crystallization is carried out after the first-stage crystal is dissolved; the secondary centrifugal separation system is used for separating secondary crystals; through two-stage crystallization coupling, mother liquor graded circulation, a unique gradient washing process and active impurity control, efficient and continuous production of battery-grade ammonium dihydrogen phosphate with wet-process phosphoric acid as a raw material is realized, the product purity is high, the process flow is simplified, the cost is low, and the system operation is stable.

Disclosed are a room-temperature and ambient-pressure superconducting ceramic and methods for producing the same. The superconducting ceramic is represented by Formula 1: A10-xBx(PO4)6O wherein A is Ca, Ba, Sr, Sn or Pb, B is Cu, Cd, Zn, Mn, Fe, Ni or Ag, and x is 0.1 to 2.0. The superconducting ceramic exhibits superconductivity at room temperature and ambient pressure. The methods are suitable for producing the superconducting ceramic.

The invention provides an industrial-grade monoammonium phosphate crystal, a preparation method thereof and an iron phosphate crystal, and belongs to the field of battery materials, the industrial-grade monoammonium phosphate crystal is of a prism-shaped structure, the two ends of the prism are in a four-side conical shape, and the particle size of the prism is 500-700 microns; in percentage by mass, in the industrial grade monoammonium phosphate crystal, the content of P2O5 is greater than 61%, the content of N is greater than 11.5%, and the content of F ions is 50-150mg / kg. The wet-process phosphoric acid is used as a raw material, the phosphoric ore pulp, the defluorination agent and the ammonia-containing solution are sequentially introduced, desulfurization, defluorination and neutralization are performed respectively, and all reaction process parameters are strictly controlled, so that impurities are remarkably reduced; the prepared product is regular in particle morphology, uniform in particle size distribution and high in phosphorus and nitrogen content, and the lithium iron phosphate positive electrode material prepared from the precursor has good electrical properties; the preparation method has the advantages of simplicity in operation, easiness in reaction control, low cost and the like, and is suitable for large-scale industrial production.

The invention relates to the technical field of water treatment, in particular to a sludge phosphorus release and phosphorus crystal recovery device which comprises a phosphorus release mechanism and a phosphorus crystal recovery mechanism, and the phosphorus release mechanism comprises a sludge concentration unit, a sludge breaking assembly and a sludge dewatering unit; the sludge disintegration assembly comprises a sludge disintegration unit and a pH value adjusting unit, the phosphorus crystal recovery mechanism comprises an outer shell, a middle shell, an inner shell, a plug flow stirring assembly, a folded plate vortex assembly, a modular vortex assembly, an inclined plate assembly and a micro-nano aeration disc, the outer shell, the middle shell and the inner shell are combined to form a unique circulation channel, and the outer shell, the middle shell and the inner shell are combined with the micro-nano aeration disc; according to the method, small-particle crystals are used as seed crystals to enter a circulating channel, so that ready-made nucleation sites are provided for a solution, the critical supersaturation degree required for forming new crystal nucleuses is reduced, the probability of spontaneous nucleation is reduced, the generation of irregular dendritic or needle-shaped crystals is inhibited, and the formation of more compact and uniform prismatic or sheet-shaped large-particle crystals is promoted; and efficient phosphorus release and phosphorus crystal recovery are realized.

The invention relates to the technical field of chemical equipment, and provides a phosphate continuous crystallization system and a phosphate manufacturing method. Comprising a monoammonium phosphate generation system, an integrated continuous crystallizer, a crystallization circulating pump, a crystallization heater, a crystallization vacuum condensation system, a crystallization material pump, a thickener and a centrifugal machine, a raw material input end of the integrated continuous crystallizer is used for being connected with a second-concentration raw material phosphoric acid and ammonia gas, or is connected with a monoammonium phosphate slurry output end of a monoammonium phosphate generation system, and a circulating material output end of the integrated continuous crystallizer is connected with a circulating material input end through a crystallization circulating pump and a crystallization heater in sequence; the crystallized material output end is connected with the input end of the centrifugal machine through the crystallized material pump and the thickener in sequence, and the centrifugal machine outputs phosphate to be dried. And process equipment for reaction, concentration, crystallization, tail gas washing and the like is not needed any more, so that the number of required equipment and the occupied area are greatly reduced, and the initial investment cost and the long-term operation cost are reduced.

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 resourceful treatment method of a lithium iron phosphate waste liquid, which comprises the following steps: filtering the lithium iron phosphate waste liquid to obtain a lithium iron phosphate filtrate; adding an oxidizing agent into the lithium iron phosphate filtrate until the redox potential value reaches a potential preset value to obtain redox liquid; adding phosphate into the redox solution for precipitation, and filtering to obtain an iron phosphate crystal product and a lithium ion filtrate; adding sodium carbonate into the lithium ion filtrate for precipitation, and filtering to obtain a lithium carbonate crystal product and wastewater. According to the method, redox reaction and chemical precipitation are combined, effective resource utilization of the lithium iron phosphate waste liquid is achieved, iron elements and lithium elements are subjected to fractional precipitation, the resource recovery rate can be effectively increased, the resource recovery benefit is high, the recovery purity can be effectively improved, the operation difficulty is low, and the method is suitable for industrial production. And the recovery cost and the equipment cost can be effectively saved.

The utility model discloses a monoammonium battery crystallizer operation device. The device comprises a crystallizer A, a crystallizer B, a crystallizer C, a crystallizer D, a crystallizer E, a crystallizer F, a crystallizer header pipe, crystallizer branch pipes, a first discharging pipe assembly and a second discharging pipe assembly, and the crystallizer A, the crystallizer B, the crystallizer C, the crystallizer D, the crystallizer E and the crystallizer F are communicated with the crystallizer header pipe through the corresponding crystallizer branch pipes respectively. The crystallizer B and the crystallizer C are communicated with the centrifugal machine through the first discharging pipe assembly, and the crystallizer D, the crystallizer E and the crystallizer F are communicated with the centrifugal machine through the second discharging pipe assembly.

A method for production of pure phosphates comprises providing (S10) of a strip solution being an aqueous solution of one of monoammonium phosphate and monopotassium phosphate, loaded with stripped phosphate from a feed liquid comprising phosphoric acid contaminated by heavy metals and iron A base is added (S20) into the separated strip solution raising the pH to 2 – 5.5, forming of a heated solution and causing compounds comprising iron and phosphate to precipitate. A precipitant, precipitating heavy metals, is added (S30). Precipitated compounds comprising iron and phosphate and precipitated heavy metal compounds are separated (S40). The heated filtered solution is thereafter cooled off (S50) into a cooled solution, causing precipitation of phosphate compounds. The precipitated phosphate compounds are removed (S60) from the cooled solution. The cooled solution is recirculated (S70) for use as input strip solution in the stripping operation. A system for production of pure phosphates is also disclosed.

A method of recovery of ammonium phosphate comprises providing a start material (100) comprising struvite into a first aqueous process liquid (101) comprising monoammonium phosphate. The first aqueous process liquid (101) is mixed. Thereby the start material (100) comprising struvite is converted into monoammonium phosphate and / or diammonium phosphate in solution and a residue (103) comprising newberyite as a precipitate. The residue (103) is separated from the first aqueous process liquid (101), thereby giving a second aqueous process liquid (104) comprising monoammonium phosphate and / or diammonium phosphate. At least a part of said second aqueous process liquid (104) or a part of an aqueous process liquid (107, 112) emanating therefrom is returned into the first aqueous process liquid. Phosphoric acid (110) is added. A method for extracting nitrogen from reject water, an arrangement (1) for recovery of monoammonium phosphate and a system for extracting nitrogen from reject water is also disclosed.

The invention relates to a wet-process phosphoric acid production process for phosphorite all-element resource comprehensive utilization, and belongs to the field of phosphorus chemical industry production. The process comprises the following steps: decomposing phosphorite, a decomposition solution and a base solution to obtain a primary decomposition solution and primary decomposition slag; crystallizing the primary decomposition liquid to obtain ammonium dihydrogen phosphate crystals and crystallization mother liquor thereof; ammonium dihydrogen phosphate is directly sold as a product or transformed to produce high-quality phosphoric acid, and the obtained crystallization mother liquor is returned to be used for preparing a decomposition solution or a decomposition base solution; transforming the primary decomposition slag by ammonium bicarbonate to obtain an ammonium sulfate solution and a calcium carbonate filter cake; returning the ammonium sulfate solution for preparing decomposition liquid or comprehensively utilizing; transforming the calcium carbonate filter cake through ammonium chloride to obtain a mixed gas containing CO2 and NH3, a calcium chloride solution and insoluble filter residues; the calcium chloride solution further produces a calcium-containing compound. According to the process provided by the invention, the phosphogypsum can be consumed from the source, the consumption of sulfuric acid is low, the fluorine leaching rate is high, the comprehensive utilization rate of calcium resources is high, and the quality of phosphoric acid obtained through transformation is good.

The present invention relates to a method for producing liquid NPK fertilizer, characterized in that the reactants K2CO3 or KHCO3, NH4HCO3, and H3PO4 are reacted in an aqueous solution to produce potassium and ammonium phosphate salts, particularly K3PO4 and (NH4)3PO4; the reaction is carried out in multiple steps and includes at least one exothermic reaction and at least one endothermic reaction; and the temperature of the reaction is controlled by adjusting the amount and rate of addition of each reactant in the various steps so as to maintain the reaction mixture within a desired temperature range, preferably between 5°C and 50°C, throughout the reaction, without the need for external cooling or heating devices to control the temperature of the reaction. In a more specific embodiment, the method according to the invention is characterized in that at least one exothermic reaction comprises the reaction of K2CO3 with HO to produce KHCO3 and KOH and / or the reaction of KHCO3 with H3PO4 to produce K3PO4, CO2, and HO, and at least one endothermic reaction comprises the reaction of NH4HCO3 with H3PO4 to produce (NH4)3PO4, CO2, and HO.

The invention discloses a method for producing 55% powdery monoammonium phosphate by using filter-press white fertilizer and phosphoric acid sludge acid, and belongs to the technical field of production of powdery monoammonium phosphate. According to the method for producing novel 55% powdery monoammonium phosphate in a tubular reactor by using waste white fertilizer and phosphoric acid sludge acid which cannot be treated in the filter-press production process, the production process flow is greatly shortened, the production cost is reduced, and the production efficiency is improved. The number of process pipelines and production equipment is reduced, the length of the process pipelines is shortened, the energy consumption and the equipment maintenance cost are greatly reduced, and the effects of saving energy, reducing consumption and improving quality and efficiency are achieved; meanwhile, the waste white fertilizer which cannot be treated in the filter pressing production process and the waste phosphoric acid slag slurry generated in phosphoric acid production are treated, and the production cost is reduced.

The invention relates to the field of wastewater treatment, in particular to a method for treating wastewater containing phosphorus, aluminum, silicon and organic amine generated in a molecular sieve preparation process, which comprises the following steps: 1) adding a pH regulator and an optional silicon-aluminum component regulator into the wastewater to enable the pH of the wastewater to be 10-14 and the molar ratio of silicon to aluminum in the wastewater to be (1.0-1.8): 1, obtaining a first mixture containing an oil phase; 2) distilling the first mixture obtained in the step 1) to obtain a gas phase and a second mixture; 3) performing solid-liquid separation on the second mixture obtained in the step 2) to obtain a first solid phase and a third mixture; and 4) crystallizing the third mixture obtained in the step 3) to obtain a second solid phase. According to the method, harmless treatment can be conducted on the wastewater, organic amine, phosphorus, aluminum, silicon and the like in the wastewater can be efficiently recovered, and the recovery rate and the purity of the recovered product are high.

The invention discloses a phosphoric acid ammoniation evaporator and a phosphoric acid ammoniation neutralization system and method.The phosphoric acid ammoniation neutralization system comprises a heat exchanger and a phosphoric acid ammoniation evaporator, and the phosphoric acid ammoniation evaporator comprises an evaporator body and a circulating ammonium phosphate pipeline connected with the evaporator body; a circulating ammonium phosphate inlet and an ammonium phosphate product outlet are formed in the two side faces of the evaporator body respectively, the position of the ammonium phosphate product outlet is higher than that of the circulating ammonium phosphate inlet, a gas outlet is formed in the top of the evaporator body, a circulating ammonium phosphate outlet is formed in the bottom of the evaporator body, and the two ends of a circulating ammonium phosphate pipeline are communicated with the circulating ammonium phosphate inlet and the circulating ammonium phosphate outlet respectively. An ammonia inlet and an acid inlet are respectively formed in the circulating ammonium phosphate pipeline, and the ammonia inlet is positioned behind the acid inlet along the circulating direction of ammonium phosphate; a heating medium inlet of the heat exchanger is connected with a gas outlet of the evaporator body, a heating medium outlet of the heat exchanger is connected with a condensate pipeline, a refrigerant inlet of the heat exchanger is connected with a phosphoric acid liquid pipeline, and a refrigerant outlet of the heat exchanger is connected with the acid inlet through a pipeline.

The invention discloses a DAP production system and method.The DAP production system comprises a DAP pelletizer, an MAP pelletizer, a classifying screen and a crusher which are sequentially arranged, the DAP pelletizer and the MAP pelletizer are internally connected with a first tubular reactor and a second tubular reactor respectively, phosphoric acid with the low concentration reacts with ammonia in the first tubular reactor, and phosphoric acid with the low concentration reacts with ammonia in the second tubular reactor; then spraying the ammonium phosphate slurry on a material in a DAP granulator for granulation, burying an ammonia distributor in the material, ammonifying and neutralizing ammonium phosphate in the material, and feeding the neutralized and granulated granular DAP material into an MAP granulator; the method comprises the following steps of: reacting phosphoric acid with high concentration with ammonia in a second tubular reactor to generate ammonium phosphate slurry, spraying the ammonium phosphate slurry into an MAP granulator, forming MAP fine particles from the slurry in airflow in the MAP granulator, drying and granulating the material by using reaction heat, screening the dried material, and taking the qualified material as a target product.