62results about "Ammonium salt preparation" patented technology

The invention belongs to the technical field of comprehensive utilization of waste resources from the aluminum industry and specifically discloses a comprehensive utilization method of aluminum ash. According to the comprehensive utilization method of aluminum ash, metallic aluminium is extracted from aluminum ash through an ore grinding method; the aluminum ash obtained after aluminium extraction undergoes catalytic deamination; the aluminum ash obtained after deamination is mixed with alkali and granulation forming is then carried out; and the granulation product is sintered and the sintered product is finally dissolved out. By the above method, useful components in the aluminum ash can be recovered to the maximum; ammonia gas which has been ignored for a long time is effectively recovered; components such as aluminium oxide, villiaumite and the like are recovered and utilized to the maximum; pollution of aluminum ash processing to the environment is avoided; atmospheric dust pollution is avoided; atmospheric pollution is also avoided due to ammonia gas recovery; pollution of aluminum ash stacking to underground water and soil is avoided due to extraction and recovery of fluoride salt; and environmental safety during the treating process is guaranteed.

A method for recovering inorganic salt during processing of a lignocellulosic feedstock is provided. The method comprises pretreating the lignocellulosic feedstock by adding an acid to the feedstock to produce a pretreated lignocellulosic feedstock. A soluble base is then added to the pretreated lignocellulosic feedstock to adjust the pH and produce a neutralized feedstock. The neutralized feedstock is then enzymatically hydrolyzed to produce an enzyme hydrolyzed feedstock and a sugar stream. Inorganic salt is recovered from either a stream obtained from the lignocellulosic feedstock prior to the step of pretreating, a stream obtained from the pretreated lignocellulosic feedstock, a stream obtained from the neutralized feedstock, a stream obtained from the sugar stream, or a combination of these streams. The inorganic salt may be concentrated, clarified, recovered and purified by crystallization, electrodialysis drying, or agglomeration and granulation, and then used as desired, for example as a fertilizer.

The present invention provides a process for removing ammonia as an aqueous salt solution from an acid gas comprising ammonia and hydrogen sulfide. A strong acid, such as sulfuric acid, is used as a scrubbing agent to convert ammonia to an ammonium salt. Control of pH and stripping in combination with reboiler or evaporators reduces hydrogen sulfide concentration. The ammonium salt is produced as an aqueous solution, which may crystallized to form a solid product. The ammonium salt solution or solid may be used as a fertilizer.

A system and method for passive capture of ammonia in an ammonia-containing liquid effluent. The invention allows for the passage of ammonia through microporous hydrophobic gas-permeable membranes and its capture in a circulated stripping solution with concomitant production of a concentrated non-volatile ammonium salt.

The invention discloses a separating method of multi-ammonia composite salt, which comprises the following steps: separating ammonia thiocyanate under low temperature (0-25 deg.c); enriching ammonium thiosulfate and ammonium sulfate under middle temperature (40-65 deg.c); separating ammonium sulfate under high temperature (80-90 deg.c); separating enriched ammonium thiosulfate at 20-40 deg.c; dissolving, crystallizing and separating solid from liquid for several times under different temperature to separate ammonium thiocyanate, ammonium thiosulfate and ammonium sulfate one by one.

An economical method for recovering phosphate or phosphate and nitrogen from liquid streams. A liquid containing phosphate is introduced into a culture of autotrophic microorganisms in the presence of natural or artificial light, thereby producing a liquid effluent with elevated pH and reduced alkalinity. The alkalinity is reduced through the consumption of bicarbonate/carbonate by the autotrophic microorganisms. The effluent is then chemically treated with low-cost chemicals to provide Ca⁺⁺ or Mg⁺⁺ ions necessary to form a phosphate precipitate such as calcium phosphate or magnesium-ammonium-phosphate (MAP). The autotrophic microorganisms can be cultivated in ponds, lagoons, or photobioreactors. The pH of the culture is adjustable within a preferred range of 7.5 to 10.5 by adjusting the photobioreactor operation. The process includes an economical flotation separator for solid, liquid, gas separation and a means of concentrating ammonia nitrogen that may also be removed during the process of phosphate reclamation.

The invention relates to a surface coating method of ammonium salts. The method comprises emulsifying a mixture of a disperse medium, an aqueous formaldehyde solution and a silicate solution through a conventional emulsification method to obtain a water in oil type emulsion or a water in oil type microemulsion, adding ammonium salt particles, which need to be coated, into the emulsion or the microemulsion, mixing the ammonium salt particles and the emulsion or the microemulsion at a normal temperature to make a surface of each one of the ammonium salt particles be coated with a uniform and dense coating layer, and treating the resulting products by separating and drying processes to make surfaces of the ammonium salt particles be coated with water-insoluble silica coating layers. Comparedwith other physical coating methods, the method provided by the invention has the characteristics of uniform and dense coating layer, no agglomeration between particles and controllability of a coating thickness, and a moisture rate of a sample coated through the method provided by the invention is far lower than moisture rates of samples coated through other methods.

A system and method for passive capture of ammonia in an enclosure containing material that gives off ammonia. The invention allows for the passage of gaseous NH₃ through microporous hydrophobic gas-permeable membranes and its capture in a circulated acidic solution with concomitant production of a concentrated non-volatile ammonium salt.

The present invention is a system and process for livestock waste management that operates more efficiently than existing technologies with less maintenance and with less chemical process components (and thus chemical handling) with recovery of useful end products. The invention comprises solids separation of the waste to remove solids in excess of about 0.50 mm in size prior to anaerobic digestion followed directly by solids separation preferably using an ultra filter and then ammonia recovery.

The invention discloses a device for recovering nitrogen element in aluminum ash. The device comprises a reaction kettle and an absorption tower, wherein the reaction kettle communicates with the absorption tower by means of a pipe for collecting ammonia gas. The device for recovering nitrogen element in aluminum ash, provided by the invention, is characterized in that: the aluminum ash is hydrolyzed in the reaction kettle to generate ammonia gas, and the ammonia gas is transported via a pipe and collected by the absorption tower, so that the nitrogen element in the aluminum ash is recovered to an utmost extent, pollution of the aluminum ash on the environment in the later processing course is avoided, and harmless, recycled and beneficial treatment of the aluminum ash is achieved.

The invention provides a treatment method of biogas liquid. According to the treatment method, after the pH (potential of Hydrogen) value of original biogas liquid is adjusted, ammonia nitrogen in the biogas liquid is subjected to preliminary recovery by adopting acidic absorption liquid through a way of absorption by a hollow fibrous membrane component; afterwards, the biogas liquid obtained by contact absorption is subjected to an anaerobic reaction, a facultative reaction and an aerobic reaction in sequence. By using the method provided by the invention, the ammonia nitrogen in the biogas liquid can be converted into an ammonium salt to carry out recycling; the concentration of the ammonia nitrogen in the biogas liquid is decreased; the subsequent biological denitrification and dephosphorization are facilitated. The treatment method is simple in process and low in cost. In the method provided by the invention, the concentration of the ammonia nitrogen in the biogas liquid subjected to the contact absorption is decreased to 20mg/L to 50mg/L; in the biogas liquid subjected to whole-course treatment, the TP (Total Phosphorus) index is 6mg/L to 8mg/L, the concentration of the ammonia nitrogen is 10mg/L to 30mg/L, the COD (Chemical Oxygen Demand) is 50mg/L to 220mg/L, and the pH value is 7 to 9; the national Discharge Standard of Pollutants for Livestock and Poultry Industry (GB18596-2001) is met.

The invention discloses a system and a method for treating and recycling carnallite in the coal chemical industry. The system comprises a carnallite pretreatment unit, a double decomposition reaction unit, a sodium bicarbonate separation unit, an NH3 and CO2 recovery unit and an ammonium salt separation unit; the carnallite is treated by equipment such as a carnallite pretreatment unit, a double decomposition reaction unit, a sodium bicarbonate separation unit, an NH3 and CO2 recovery unit and an ammonium salt separation unit to obtain ammonium chloride, ammonium sulfate and sodium bicarbonate products. According to the method, the sodium sulfate/sodium chloride waste salt, NH3 and CO2 are used as raw materials, the final products obtained after reaction are ammonium chloride, ammonium sulfate, sodium bicarbonate and other bulk chemical products, the market demand is large, resource utilization of the waste salt is achieved, and economic benefits and environmental benefits are remarkable.

The invention discloses a process for recycling ammonia gas for vanadium preparation to prepare ammonium and recycling wastewater. Conventional vanadium extraction processes are complex in procedure and most difficult in control of ammonia gas emission and wastewater treatment. By the process, ammonium metavanadate and ammonium polyvanadate can be directly extracted starting from mining and smelting; in the process of using ammonium metavanadate or ammonium polyvanadate to prepare high-purity vanadium pentoxide, all discharged ammonia gas can be bundled to prepare ammonium for use, so that zero emission of waste gas is realized; polyacid ester flocculation technology is adopted, all wastewater generated in the above process is effectively treated, so that zero emission and recycling of wastewater are ensured, and purity of all products reaches 99.5-99.99%.

The invention relates to a comprehensive treatment method for wastewater generated in iron phosphate production, the wastewater is divided into washing water and mother liquor, the comprehensive treatment method is characterized by comprising the following steps: (S1) washing water treatment: (S2) mother liquor treatment: A, fluorine removal; b, phosphorus removal; c, removing manganese; d, producing by-product calcium sulfate; e, removing calcium and magnesium; f, removing ammonia; and G, circulating. Zero emission of the iron phosphate wastewater is realized through process optimization, and according to different properties of various impurities, grading separation and recovery are performed, so that the resources are recovered to the maximum extent. According to the method, fluorine ions in the wastewater are removed in the early stage, a high-quality iron phosphate byproduct can be obtained, manganese dioxide and calcium sulfate are obtained in the subsequent stage, new impurities are not introduced while resources are recycled, a little surplus is obtained through cost benefit accounting, and the method is a comprehensive wastewater treatment method with great economic value.