376results about "Ammonium sulfates" patented technology

The invention discloses a resourceful treatment method for wastewater containing magnesium and manganese ammonium sulfate, and belongs to the technical field of wastewater resourceful treatment. The method comprises the following steps: neutralizing the ammonium sulfate wastewater containing magnesium and manganese to remove heavy substances, deeply removing calcium from the neutralized and precipitated filtrate by adopting oxalic acid and a crystal inducer through crystallization, leaching the calcium-removed and precipitated filter residue by adopting sulfuric acid, recycling the leachate which is an oxalic acid solution, and removing manganese from the calcium-removed and precipitated filtrate through catalytic oxidation and decomposing residual oxalic acid to obtain manganese residues and catalytic oxidation filtrate; according to the method, the magnesium-manganese-containing ammonium sulfate wastewater can be subjected to resourceful treatment to obtain the magnesium ammonium sulfate product and the ammonium sulfate product with relatively high additional value, and the problems of difficulty in impurity removal, low cost and the like in the existing magnesium-manganese-containing ammonium sulfate wastewater treatment process are solved. The purity of by-products is low, and the like.

The invention relates to a method for preparing high-quality ammonium sulfate by using sodium-ammonium-containing sulfate solid waste, which comprises the following steps: partially dissolving the sodium-ammonium-containing sulfate solid waste and carrying out solid-liquid separation to obtain a first dissolved solution and a first solid phase; the first dissolving solution is subjected to first evaporative crystallization and solid-liquid separation, and an ammonium sulfate product and a first mother solution are obtained; wherein the temperature of partial dissolution is 5-10 DEG C; efficient separation and recovery of ammonium sulfate and sodium sulfate resources in sulfate solid waste containing sodium and ammonium are achieved, the purity of an ammonium sulfate product obtained after first evaporative crystallization is preferably as high as 98.6% or above, the appearance color is white, the water content is preferably as low as 1.3% or below, and the recovery rate is high. The recovery rate is preferably up to 98.00% or above, the purity of the sodium sulfate product is up to 98.5% or above, the amount of sodium hydroxide required to be consumed is as low as 0.93% or below, and the method is simple in technological process, mild in condition and easy to industrialize.

The invention discloses a BOE waste liquid treatment method and device. The method comprises the following steps: replacing hydrogen fluoride in BOE waste liquid with sulfuric acid, evaporating, fractionating and recovering hydrofluoric acid, neutralizing evaporated residual liquid with ammonia to obtain a fluorine-containing ammonium sulfate solution, defluorinating with fluorgypsum slurry to obtain a low-fluorine ammonium sulfate solution, and concentrating and crystallizing to obtain an ammonium sulfate product. The BOE waste liquid is treated by adopting the scheme, the bottleneck of the market capacity of ammonium bifluoride is avoided, the hydrofluoric acid product and the ammonium sulfate product with huge market capacity are produced, the value orientation of turning waste into wealth, circular economy and environmental protection is really realized, and the method is suitable for industrial popularization and application.

The invention belongs to the technical field of lithium-containing waste treatment, and particularly discloses a method for preparing lithium carbonate by recycling lithium through cooperative treatment of lithium-containing waste. The method specifically comprises the following steps: mixing a lithium amide waste material, a lithium sulfide waste material and water, then mixing with a hydrogen peroxide solution and a sulfuric acid solution, and carrying out an acid dissolution reaction to obtain a lithium-containing acid solution and an insoluble substance; mixing the lithium-containing acid solution with alkali liquor, and carrying out alkalization reaction to obtain insoluble impurities and alkalized feed liquid; concentrating the alkalized feed liquid to obtain concentrated alkalized feed liquid, and mixing the concentrated alkalized feed liquid with a sodium carbonate solution for lithium precipitation reaction to obtain lithium precipitation mother liquor and lithium carbonate; extracting the lithium element in the lithium precipitation mother liquor, and evaporating and concentrating the raffinate to separate out sodium sulfate and ammonium sulfate; ammonium sulfate and the lithium iron phosphate waste are mixed and then sequentially subjected to roasting and leaching, and a leaching solution and a lithium-containing acid solution are mixed for alkalization. The method has the characteristics of high process integration level, high economic value and less environmental pollution, and conforms to the new concept of chemical green atom economy.

The invention provides a lithium bis (fluorosulfonyl) imide heavy slag treatment method which comprises the following steps: reacting bis (fluorosulfonyl) imide heavy slag to be treated with an aqueous solution of an alkaline compound to obtain a reaction solution containing a salt compound and ammonia gas; and recovering the reaction liquid to obtain the salt compound. By means of the method, resource recycling can be conducted on the lithium bis (fluorosulfonyl) imide heavy slag, economic benefits are improved, and the method has important significance in promoting sustainable development and circular economy.

The invention belongs to the technical field of environmental protection, and particularly relates to a cement kiln flue gas desulfurization and decarburization and mineralization solid waste gypsum integrated treatment method, an adopted treatment system comprises a reaction tower, and the reaction tower is sequentially divided into a desulfurization area, a decarburization area, a mineralization reaction area II and a mineralization reaction area I through partition plates from bottom to top; a washing area is further arranged above the first mineralization reaction area, raw flue gas of the cement kiln is input from the bottom and discharged after being sequentially treated by all the areas, and solid waste gypsum slurry prepared by a solid waste gypsum slurry preparation tank is sprayed downwards from the upper portion of the first mineralization reaction area. Solid waste gypsum slurry accumulated at the bottom of the first mineralization reaction area is input into a second filter to be filtered, then the filtered solid part is evenly sprayed downwards from the upper portion of the second mineralization reaction area, filtrate output by the second filter is subjected to evaporative crystallization, and an ammonium sulfate product is obtained. According to the method, the technical problem of insufficient reaction caused by difficult realization of removal of reaction raw materials and enrichment of reaction products is solved.

The invention relates to the field of preparation of battery materials and precursors of the battery materials, and discloses a method for efficiently preparing battery-grade manganous-manganic oxide by using electrolytic manganese residue leachate and a harmless treatment method for tail liquid of the battery-grade manganous-manganic oxide. Treating the manganese residue leachate concentrated water obtained in the previous step with ammonia water and oxygen to prepare battery-grade manganous-manganic oxide; adjusting the pH value of the filtrate obtained in the previous step to prepare magnesium hydroxide; the filtrate obtained in the previous step is subjected to evaporative crystallization, ammonium sulfate is prepared, finally, harmless treatment of preparation of battery-grade manganous-manganic oxide from the manganese residue leachate and the tail liquid of the battery-grade manganous-manganic oxide is achieved, and the recovery efficiency of valuable components is greatly improved.

The invention relates to a treatment device and method for wet oxidation produced water of caprolactam wastewater. The treatment device comprises a produced water collection tank, a membrane filtration device, an electrolysis device, a macroporous adsorption resin column and a chelating adsorption resin column. The treatment method comprises the following steps: (1) adjusting the pH value of the wet oxidation produced water of the caprolactam wastewater, and then carrying out membrane filtration concentration; (2) carrying out electrolytic treatment on the obtained concentrated water; (3) carrying out resin adsorption on the obtained electrolysis wastewater; and (4) carrying out advanced treatment on the obtained adsorption wastewater. The device disclosed by the invention is simple in structure, large in treatment capacity, free of additional byproducts and three wastes, green, environment-friendly, safe and reliable. The method is simple in process, high in COD removal rate, high in catalyst metal ion and ammonium sulfate recovery rate, high in ammonium sulfate purity and good in fresh water biodegradability, solves the problem of membrane pollution of a membrane filtration device caused by high-concentration metal ions in wastewater, improves the efficiency of an electrolysis device, is low in cost and is suitable for industrial production.

The utility model relates to a spray type saturator which comprises a separation chamber and a crystallization chamber which are communicated through a downcomer, a reverse spraying pipe and an empty spraying pipe are arranged at the upper part of the separation chamber; the upper end of the reverse spraying pipe is a coal gas inlet, and the lower end is internally provided with a primary mother liquor nozzle; the inlet of the pipeline extends out of the side part of the separation chamber; a coal gas outlet is formed in the upper end of the air spray pipe, and a secondary mother liquor spray head and a demister are sequentially arranged in the air spray pipe from bottom to top; the inlet of the pipeline extends out of the side part of the empty spraying pipe; and the primary mother liquor spray head is a dynamic wave spray head. The demister has the advantages of low power consumption, high demisting efficiency, high deamination efficiency and the like.

Methods of purifying ammonium products, such as ammonium sulfate, from an aqueous ammonium-containing process stream are described. The process stream may be a waste stream from an industrial process, such as from acrylonitrile production, for example. Such process streams typically contain a number of organic contaminants. The methods involve removing water from the process stream and then treating the process stream to oxidatively destroy the organic contaminants. In the described methods, the oxidant used is a strong acid, such as concentrated sulfuric acid. The acid is added at a concentration and rate that is effective at oxidatively removing the organic carbon in the stream while avoiding complications from competing side reactions. Once the process stream is sufficiently free of such contaminants, the ammonium products can be granulated.

The invention relates to a method for recycling a negative electrode plate of a waste graphite lithium ion battery. The method comprises the following steps: carrying out thermal decomposition treatment on the negative electrode plate to be recycled; carrying out ammonia water absorption treatment on the tail gas obtained by the thermal decomposition treatment to obtain absorption liquid; adjusting the pH value of the absorption liquid to 8.0-10, carrying out precipitation treatment on the absorption liquid by adopting an iron salt solution, and collecting a first precipitate and a first reaction liquid; carrying out resin weight removal on the first reaction solution to obtain a lithium precipitation solution; sequentially performing sulfuric acid leaching and solid-liquid separation on a solid material obtained by thermal decomposition treatment, and recovering graphite and first filtrate; adjusting the pH value of the first filtrate to 4.0-4.5, and collecting lithium fluoride and a second filtrate; carrying out precipitation treatment on the second filtrate, and collecting a second precipitate and a second reaction solution; carrying out resin weight removal and concentration treatment on the second reaction liquid to obtain a mixed solution containing ammonium fluoride and ammonium sulfate; and mixing the mixed solution with the lithium precipitation solution to obtain a lithium fluoride and ammonium sulfate solution.

The invention belongs to the technical field of solid waste control, and particularly relates to a VOCs catalyst based on manganese slag, a preparation method and application of the VOCs catalyst and a manganese slag resource utilization method. The method comprises the following steps: mixing manganese slag with a sulfuric acid solution, and carrying out solid-liquid separation to obtain a washing solution and washing slag; mixing the washing solution and the carbonate aqueous solution, and sequentially carrying out precipitation reaction, standing and solid-liquid separation to obtain a precipitate and a separation solution; roasting the precipitate to obtain a roasted substance, washing the roasted substance with an organic acid solution and water in sequence, and then drying to obtain a purified product; mixing the purified product, a binder and water to obtain a mixed material; the mixed material is subjected to extrusion molding and then dried, and the VOCs catalyst based on the manganese slag is obtained. According to the method, resource utilization of metal elements in the manganese slag is achieved, and the excellent VOCs catalytic oxidation effect is achieved on the premise that the production cost of the catalyst is greatly reduced.

The invention relates to the technical field of preparation of nano aluminum oxide, in particular to a preparation method of high-purity nano aluminum oxide, which comprises the following steps: dissolving aluminum ammonium sulfate in high-temperature hot water, filtering, recrystallizing, drying the recrystallized aluminum ammonium sulfate to remove moisture to obtain dried aluminum ammonium sulfate, and roasting the dried aluminum ammonium sulfate at high temperature to obtain the high-purity nano aluminum oxide. The preparation method comprises the following steps: calcining the alumina powder, decomposing to generate alpha-Al2O3 nano-alumina, simultaneously releasing ammonia gas and sulfur dioxide gas, introducing the ammonia gas and sulfur dioxide released in the roasting process into water through a negative pressure absorption device to generate an ammonium sulfate solution, and finally obtaining the superfine alumina powder with the particle size reaching the nanoscale. According to the method, the market value of the product is improved, ammonia gas and sulfur dioxide generated in the roasting process are absorbed to successfully generate a byproduct ammonium sulfate, and the byproduct ammonium sulfate is reused in a catalyst wet vanadium precipitation process, so that the environmental pollution is reduced, the output quality of aluminum oxide is improved, and the production loss caused by impurities is reduced, thereby improving the production efficiency and economic benefits.

The invention provides a method for recovering sodium sulfate from salt-containing wastewater and preparing ammonium sulfate and sodium carbonate, and the method comprises the following steps: controlling sodium sulfate and sodium chloride to be close to a co-saturation point at an evaporation temperature, so that more impurities such as Cl <-> can be prevented from being mixed into solid sodium sulfate, and the solid sodium sulfate separated out from the salt-containing wastewater is higher in purity; the sodium carbonate and the ammonium sulfate are prepared from the separated high-purity sodium sulfate, the prepared sodium carbonate and the ammonium sulfate are fewer in impurities and higher in purity, and according to measurement, the purity of the obtained sodium sulfate is 99.0% or above, the conversion per pass of ammonium bicarbonate is 90% or above, the purity of the sodium carbonate is 98% or above, and the purity of the ammonium sulfate can meet the requirements of GB / T535-2020. The method not only can be used for preparing a product with higher purity, but also has better environmental benefits and economic benefits, and can better meet the requirements of current green metallurgy and solid waste recycling on clean production.

The invention relates to the technical field of solid waste recycling, and provides a secondary aluminum ash wet treatment resource utilization method which comprises the following steps: S1, a pretreatment step, S2, a slurrying reaction step, S3, a slurry impurity removal step, S4, an enhanced reaction step and S5, an oxidation reaction step. S6, a carbonization reaction step; s7, a flocculating settling step; s8, washing and separating; the step S1 is a pretreatment stage, the steps S2-S6 are wet reaction stages, the steps S7-S8 are solid-liquid separation stages, and the step S9 is a product drying stage, and the method has the effects that the secondary aluminum ash treatment process is simplified, the cost is reduced, and recycling products are enriched.

The present invention provides a method and device system for preparing sodium carbonate and / or sodium bicarbonate and co-producing ammonium sulfate from sodium-based wastewater. According to the phase equilibrium law of a multi-component water-salt system, through the regulation of crystallization kinetics and supersaturation, the sodium-based wastewater does not need to be evaporated and crystallized to produce sodium sulfate solid. Instead, the wastewater after simple pretreatment is directly treated to achieve gradient crystallization separation of sodium sulfate, ammonium sulfate and sodium bicarbonate, thereby obtaining high-quality sodium bicarbonate, sodium carbonate and ammonium sulfate products.

The present invention provides a method for preparing soda ash or baking soda by resource utilization of coal chemical concentrated brine, the method comprising: removing harmful impurities from coal chemical concentrated brine by induced crystallization, acidolysis and thermally stimulated oxidation to obtain mixed salt and mixed salt mother liquor; separating sodium nitrate from the mixed salt mother liquor, double decomposing and evaporating the mixed salt, ammonium chloride mother liquor and ammonium sulfate mother liquor to obtain sodium sulfate mixed crystals and ammonium chloride enriched solution; obtaining ammonium chloride and ammonium chloride mother liquor from the ammonium chloride enriched solution; dissolving and salting out the sodium sulfate mixed crystals and sodium bicarbonate mother liquor to obtain a saturated sodium sulfate solution and crude ammonium sulfate; obtaining ammonium sulfate and ammonium sulfate mother liquor from crude ammonium sulfate; double decomposing the saturated sodium sulfate solution and ammonium bicarbonate to obtain a sodium bicarbonate product and a sodium bicarbonate mother liquor. The method provided by the present invention obtains baking soda and co-produces high-value ammonium salt products from coal chemical concentrated brine in a short process and at a low cost, thereby realizing the reduction, harmlessness and resource utilization of coal chemical wastewater.

The invention discloses an ammonia desulfurization system and method based on zone control. The ammonia desulfurization system comprises a desulfurization tower, an absorption circulating tank, an ammonia water tank, a rinsing tank and a process water tank. The desulfurization tower is sequentially provided with a flue gas outlet, a demisting section, a second-section absorption layer, a first-section absorption layer and a concentration section from top to bottom. A partition plate is arranged in the absorption circulating tank and divides the absorption circulating tank into an upper oxidation tank and a lower absorption circulating section. An aeration pipe is arranged in the upper oxidation tank, and the upper oxidation tank is connected with a spraying liquid inlet of the second absorption layer through a pipeline; the lower concentration section of the desulfurizing tower is connected with the oxidation tank through a liquid conveying pipeline. The water washing tank supplies water to the demisting section and the absorption circulating tank; the ammonia water tank supplements ammonia water to the oxidation tank, the first-section absorption layer and the lower absorption circulation section respectively; recycled liquid of the demisting section is connected back to the rinsing bath through a pipeline. According to the invention, absorption and oxidation are partitioned in the same tank, so that coupling interference is eliminated; two-stage absorption and demisting recovery are matched, so that ammonia escape is effectively controlled while efficient removal of sulfur dioxide is guaranteed.

The present application relates to the technical field of ammonia compound preparation, in particular to a method for preparing ammonium sulfate and co-producing sodium bicarbonate by using sodium sulfate, comprising the following steps: mixing industrial-grade liquid ammonia with deionized water to prepare ammonia water with a free ammonia concentration of 60-120 ti (ti is the abbreviation of titer, which is 1 / 20 mol / L), controlling the temperature of the mixing process to be less than or equal to 40 DEG C to avoid ammonia volatilization, pre-carbonizing by passing in CO2 under the conditions of 20-70 DEG C and a carbon dioxide pressure of 0.1-0.6 MPa, and adding sodium sulfate or a mixture of sodium bicarbonate and mirabilite to obtain a pre-carbonized liquid. The present application adopts an integrated process of pre-carbonization, clarification, carbonization, ammonia separation and low-temperature crystallization, and ammonia evaporation circulation, and can be operated continuously or intermittently, has low industrial implementation difficulty, strong running stability, separates ammonium sulfate by using ammonia separation and low-temperature crystallization technology, replaces the traditional evaporation and concentration process, combines material recycling design, and reduces the energy consumption per unit product compared with the traditional process.

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 invention provides a process for the preparation of sul furic acid and minerali zation of CO2 from industrial gases, comprising : CO2- absorption step, comprising continuously sparging C02- containing gas through an aqueous solution of ammonia in a first reactor, or continuously sparging C02-containing gas and ammonia gas through water, to form [ (NH4 ) 2CO3 / NH4HCO3 ] solution; continuously withdrawing [ (NH4 ) 2CO3 / NH4HCO3 ] solution from the first reactor and providing said [ (NH4 ) 2CO3 / NH4HCO3 ] solution, after it has been optionally cooled, to a second reactor, wherein NH3 and CO2-bearing gas stream discharged from the first reactor is fed to the second reactor, thereby producing (NH4 ) 2CO3 aqueous solution in the second reactor and releasing an essentially NH3 and CO2- free gas from the second reactor; CO2-minerlai ztion step, comprising reacting the (NH4 ) 2CO3 in water with calcium sul fate [ CaSO4 ], to form a solution of ammonium sul fate [ (NH4 ) 2SO4 ] and precipitate solid calcium carbonate [ CaCO3 ], separating CaCO3 from said solution and recovering ammonium sulfate crystals from the solution; and H2SO4- format ion step, comprising thermally decomposing the (NH4 ) 2SO4 to give sul furic acid and supplying a stream of ammonia released from the thermally decomposed (NH4 ) 2SO4 to the CO2-absorption step.

The invention relates to the technical field of environmental protection, and particularly provides a comprehensive recovery treatment system and method for waste liquid containing sulfur and various ammonium salts. The treatment system comprises a sulfur foam tank, a super centrifuge, a clear liquid tank, a concentrated acid tower, an oxidation tower, a conversion tower, a filtering system, an ammonium sulfate storage tank, a concentrated sulfur foam buffer tank, an incineration system, a purification system, a drying system, a conversion system, an absorption system and a tail absorption system. Slurry such as solid sulfur is subjected to high-temperature combustion in an incinerator to obtain flue gas containing sulfur dioxide, and then the flue gas enters a subsequent sulfuric acid production process system to prepare a finished product of industrial sulfuric acid, so that recycling of sulfur resources is realized. Ammonium thiosulfate and ammonium thiocyanate are completely converted into an ammonium sulfate product by the ammonium salt solution through oxidation, conversion and other processes, so that the recycling of nitrogen resources is realized.

The invention discloses a method for efficiently recycling ammonium sulfate in electrolytic manganese residues. The method comprises the following steps that firstly, 0.5-1.5 parts of the electrolytic manganese residues and 2-4 parts of clear water are taken and put into a stirring machine to be fully and evenly stirred; 2, adding an acidic reagent into the slurry obtained in the step 1 after fully and uniformly stirring, adjusting the pH value, and then continuously stirring to obtain slurry; 3, the slurry obtained in the step 2 is pumped into a filter press for solid-liquid separation, filtrate and filter residues are obtained, and the filtrate is collected for standby application; 4, the filtrate in the step 3 is returned to the step 1 to replace 2-4 parts of clear water, and then 0.5-1.5 parts of electrolytic manganese residues are taken and put into a stirrer to be fully and evenly stirred; 5, repeating the step 2 and the step 3 on the slurry in the step 4 to obtain filtrate for later use; the invention aims to solve the problems that the electrolytic manganese residue recovery device in the prior art needs to be washed for multiple times, the water consumption is large, other impurities are always remained in water after washing, and the subsequent treatment difficulty is increased.

The application discloses a process for preparing high-molecular-ratio cryolite and ammonium sulfate by using fluorine-containing etching waste liquid, and comprises the following steps: adding sodium metaaluminate slurry and sodium sulfate solution into the fluorine-containing etching waste liquid, then adjusting pH to be acidic by using a sulfuric acid solution, carrying out heating reaction, then carrying out centrifugal separation treatment, and drying the obtained cryolite precipitate; adding sodium metaaluminate slurry into the fluorine-containing supernatant, and obtaining defluorination filtrate by treatment; adding a sulfuric acid solution into the defluorination filtrate, carrying out neutralization reaction, then carrying out vacuum evaporation on the reaction mixture containing ammonium sulfate, carrying out centrifugal separation treatment after cooling, drying the obtained ammonium sulfate precipitate, and obtaining ammonium sulfate product. The fluorine ion in the fluorine-containing etching waste liquid can be effectively utilized, the generated cryolite product can reach the national standard of high-molecular ratio, the fluorine ion content of the generated filtrate is less, so that the filtrate can enter the synthesis of ammonium sulfate, and no waste liquid is generated in the process.

The invention relates to the technical field of chemical engineering, and discloses an amide oil separation and ammonium sulfate crystallization integrated device. Comprising a neutralization reactor, a settling separation tank, a pre-crystallization solution tank, a DTB crystallizer, a centrifugal machine, a settling separator, a dryer, a mother liquor tank, a condensate water tank, an amide oil decanter, an ammoximation tert-butyl alcohol tower reboiler, a mother liquor heater set, a condenser, a vacuumizing condensing unit, a stirrer set and a reactor circulating pump. The invention further comprises a process for preparing the large-particle ammonium sulfate crystal from the saturated amide oil solution, rearrangement liquid from a lactam rearrangement system and gas ammonia are added into a neutralization reactor through an external circulation pipeline, and the large-particle ammonium sulfate crystal is prepared by fully utilizing heat in the gas ammonia dissolution and neutralization reaction and crystallization process. By combining the compound additive, the seed crystal and the continuous crystallization technology, the generation of large-particle ammonium sulfate crystals is promoted, meanwhile, the crystallization process is optimized, an efficient amide oil separation and continuous crystallization mode is realized, the energy consumption is saved, and the production efficiency is improved.

The present disclosure relates to new methods and processes of byproduct conversion, wastewater remediation, byproduct upcycling / recycling, and sustainable cyclic methods thereof.

The invention relates to a method for recovering a magnesium element from a magnesium-containing solution and application thereof, and relates to the technical field of wastewater treatment. According to the method, magnesium precipitation separation is achieved through the steps of alkalization, carbonization, flash decomposition and the like, and basic magnesium carbonate, active magnesium oxide and ammonium sulfate with high additional values can be recycled.

The present application belongs to the technical field of pharmaceutical production, and particularly relates to a method and device for preparing L-magnesium aspartate by selective ion replacement electrodialysis. The present application uses a selective ion replacement electrodialysis device to convert an intermediate product of industrial L-aspartate production, L-ammonium aspartate, to prepare L-magnesium aspartate. The selective permeability of the ion exchange membrane is used to realize the replacement of cations in two different electrolytes, so that the ions are recombined to form L-magnesium aspartate. Thus, the deficiencies of the prior art process of first preparing L-aspartate and then preparing L-magnesium aspartate are avoided. The purity of the L-aspartate prepared according to the present method and the conversion rate of the L-ammonium aspartate both reach more than 97%, and the energy consumption is low. The L-magnesium aspartate product with high purity can be quickly prepared, and the by-product ammonium sulfate can also be obtained in the product chamber 2, thereby improving the economic benefits of the process and having important industrial application value.

The invention belongs to a comprehensive utilization device and a comprehensive utilization method for acid gas of a synthetic ammonia device. Comprising a gasification system acid gas unit, a low-temperature methanol washing system acid gas unit and a conversion stripping tower acid gas unit, wherein the gasification system acid gas unit is respectively connected with a heat tracing gas inlet of a Claus combustion furnace and a heat tracing gas inlet of a waste gas combustion furnace in a sulfur preparation unit; an acid gas unit of the low-temperature methanol washing system is connected with an inlet of the Claus combustion furnace, and an acid gas unit of the conversion stripping tower is connected with an inlet of the waste gas combustion furnace; a top tail gas outlet of the waste gas combustion furnace is connected with a tail gas treatment unit, the tail gas treatment unit is coupled with an ammonium sulfite solution preparation unit, and the ammonium sulfite solution preparation unit is connected with an ammonium sulfate preparation unit; the system has the advantages that the acid gas in the ammonia synthesis device is comprehensively treated, the circulating operation of the whole system is realized, the environment-friendly emission problem of an enterprise is solved, and meanwhile, relatively large profits are brought to the enterprise.

A process for the synthesis of hydrogen by catalytic cleavage of ammonia; the process comprising the step of subjecting an ammonia-containing stream (10) to a catalytic cleavage step (11) in the presence of heat to produce a combustion gas and a hot cleavage stream (14) containing nitrogen, hydrogen and potentially residual ammonia, and optionally water; the process further comprising the step of subjecting the hot cleavage stream to a hydrogen recovery step to produce a high-purity hydrogen stream (22).