83 results about "Ammonium bisulfite" patented technology

A method for preparing polymer for PAN precursor, by copolymerizing the water phase suspend using ammonium persulphate-ammonium sulfite or ammonium bisulfite as a primosome, is disclosed. The polyacrylonitrile powder material is obtained by adding the first monomer acrylonitrile, the second monomer crylic acid, methyl acrylate or acrylamide, and the third itaconic acid, or the first monomer crylic acid, the second monomer methyl acrylate or itaconic acid, and inorganic oxidation-reduction primosome without any metallic ion which comprises ammonium persulphate, ammonium sulfite or ammonium bisulfite and acidified deionized water into the polymerization kettle in defined proportions, controlling the temperature and stirring to react for a time, and discharging by removing the residual monomer, washing and drying. The average molecular weight is from 17.5 myriads to 26.1 myriads, and the distribution index of molecular weight is from 2.70 to 2.91; the intension of polyacrylonitrile precursor tested by spinning sample is from 4.58 to 6.61 CN/dtex; and the carbon fiber strength is 3.61-5.06MPa.

The environment friendly methyl sulfonic acid preparing process includes the following steps: the reaction of the water solution or solid of ammonium sulfite or mixture of ammonium sulfite and ammonium bisulfite with dimethyl sulfate at high temperature to produce ammonium methyl sulfonate; treating the reacted solution containing ammonium methyl sulfonate and ammonium sulfate with calcium hydroxide or other compound capable of producing precipitate with sulfate radical ion to produce water soluble calcium methyl sulfonate, water insoluble calcium sulfate and ammonium hydroxide; treating obtained calcium methyl sulfonate with strong acid capable of forming precipitate with calcium ion; and final decompression distilling to obtain methyl sulfonic acid. The present invention has facile material, simple technological process, high product quality, low cost and no environmental pollution, and is suitable for industrial production.

The invention discloses a smoke desulfurization and denitrification integration method and a special device thereof. The method is characterized in that a wet-method process is used in one technological system to simultaneously remove sulfur dioxide and nitrogen oxide in the smoke; an ammonium method is used for desulfurization, ammonia water is also used as a desulfurizer of the sulfur dioxide and a neutralizing agent for byproduct nitric acid produced in the denitrification process; an oxidization reduction method is used for the denitrification, a desulfurization byproduct ammonium sulfite or ammonium bisulfite is used as a reducing agent, urea is used as a reducing agent, a quinine-contained hydroxyl compound is used as a catalyst, air is blown into the denitrification circulating liquid so as to provide the dissolving oxygen and the oxidant for the oxidization reaction of the nitrogen oxide; a byproduct ammonium nitrate of the denitrification reaction is placed into the desulfurization liquid so as to recycle the nitrogen ammonium; and ammonia nitrogen chemical fertilizer ammonium sulfate and ammonium nitrate are recycled, and the entire technological flow is free from discharging sulfur-contained or ammonia nitrogen-contained waste liquid out of the system. Due to the adoption of the method, the integration of the desulfurization and the denitrification can be realized, the device is miniaturized, and no waste liquid is discharged in the technological process.

The invention discloses a method for preparing sulfur and processing tail gas by taking ammonium bisulfite as an intermediate and belongs to the technical field of sulfur recovery. The method is characterized by comprising the following steps: 1) separating NH3 from an acidic water stripping device by adopting the prior art to obtain gas ammonia or aqua ammonia; 2) oxidizing all non SO2 sulfides in the tail gas into SO2 through burning the tail gas in a Claus sulfur recovery device; 3) reacting the tail gas after burning and the NH3 separated from the acidic water stripping device in a liquid phase to produce NH4HSO3 and (NH4)2SO3, and discharging the purified tail gas; and 4) atomizing the NH4HSO3 and (NH4)2SO3 water solution, spraying the water solution into a reacting furnace of the Claus sulfur recovery device, decomposing the NH3 into N2 after thermal decomposition, and enabling SO2 to participate in Claus reaction to obtain an elemental sulfur. Compared with the tedious technical process of the prior art, the method has greatly shortened process, and construction investment, operating cost and energy consumption are reduced by more than 30%.

The invention relates to a method for removing and recycling SO2 in high-sulphur boiler flue gas and discloses a method utilizing ammonia water as material and recycling desulfuration to prepare ammonium bisulfite with high SO2/NH3 value and high purity. The method comprises the steps of (1) performing dry dedusting on high-sulphur boiler flue gas, and cooling through wet dust collection, (2) utilizing ammonia water as absorbents to absorb SO2 in flue gas in a triple tandem desulfurizing absorption tower, controlling the absorbing temperature through an exterior circulation cooling mode, preparing ammonium bisulfite solution with high SO2/NH3 value, and discharging with standard level after water scrubbing and demisting, (3) removing high chemical valence insoluble heavy metal ions such as ferric iron through microfiltration, and (4) removing heavy metal ions through chelating ion exchange resins to obtain products. According to the method, the concentration of SO2 in flue gas after desulfurization is low, SO2 in high-sulphur boiler flue gas is effectively recycled, and ammonium bisulfite solution with high SO2/NH3 value and high purity is prepared.

The invention discloses a fluidized bed-based flue gas combined desulfurization and denitration process. An ammonia-containing reducing agent and flue gas after dust removal are subjected to gas-phase desulfurization reaction at a desulfurization region; ammonia and sulfur dioxide react under the action of vapor to generate ammonium sulfite and ammonium bisulfite to be adsorbed by an SCR (Selective Catalytic Reduction) denitration catalyst; desulfurized flue gas is subjected to SCR denitration reaction of the ammonia-containing reducing agent and nitrogen oxide at the SCR reaction region; and after being desulfurized, regenerated and activated, catalyst grains are circulated back to the SCR reaction region to be reutilized. The invention discloses a device for implementing the process. Through the process, liquid-state sectional desulfurization and denitration are realized in a fluidized reaction tower, so that adverse effect of the sulfur dioxide in medium and low-temperature flue gas on SCR catalytic desulfurization is overcome; and the process is suitable for desulfurization and denitration of low-temperature and high-sulfur flue gas of industrial boiler kiln and has broad market application prospect.

The invention relates to a process for preparing amino G acid, which belongs to the technical field of amino K acid production process. The process comprises the steps of sulfonating, salting out by ammoniacal liquor, treating G salt mother liquor, ammoniating G salt ammonium base sulfite, treating dehydrated liquid and the like, ammonium base sulfite is employed as a catalyst for replacing ammonium bisulfite, so that the pressure generated during ammonification process can be effectively reduced, the reaction time can be shortened, and the product yield and content can be increased. The method is characterized in that two streams of waste water are respectively treated, 2-naphthol is hydrolyzed and recovered by G salt mother liquor, neutralized for reaching the standard, and then exhausted; ammonium sulfate-rich effluent is used for producing fertilizer, and the zero discharge is realized. The unit consumption of the raw material 2-naphthol is decreased from 0.75 ton/ton in a traditional process to less than 0.64 ton/ton when the problem of waste water treatment is solved, so that the production cost is reduced, the production safety coefficient is high and no harmful gas is discharged. The process of the invention solves the problems that two streams of waste water are generated during the present production process, the difficulty of waste water treatment is large, the production cost is high and the large harm on environment is caused.

The fume-desulfurizing ammonia-thiamine method is to use ammonia as carrier absorbing SO2 in coal burning fume as a kind resource. One fume desulfurizing tower is installed between the boiler exhaust and the chimney, and ammonium sulfite and ammonium bisulfite are produced through reaction and dissolved in circular solution. The solution is neutralized and forced to oxidize to produce ammonium sulfate, which is extracted in evaporating and crystallizing apparatus and is used as composite chemical fertilizer. Or, the ammonium sulfite may be synthesized in chemical plant into other different products.

The invention discloses twin tower type recovering sulfur resource ammonia desulfuration equipment and a method. The equipment comprises a dynamic wave washing tower, a primary absorption tower, a secondary absorption tower and the like; the exhaust gas passes through the dynamic wave washing tower to remove ash and passes through a dynamic wave washer to lower the temperature, and then enters the primary absorption tower and the secondary absorption tower in sequence; the primary absorption tower and the secondary absorption tower are both provided with five spraying layers; the lower three spraying layers spraying and absorbing the exhaust gas; the upper two spraying layers are used for preventing ammonia escape; and the exhaust gas is discharged after being sprayed and absorbed by the primary absorption tower and the second absorption tower. The invention has the following advantages: 1) the purity of the by-product is high; 2) the twin tower design can not only obtain higher desulfurization efficiency, but also produce by-product with high purity; 3) the technology takes ammonium acid sulfite as the ultimate by-product, not only saving the technologies of crystallization and drying in the traditional technology, but also improving the additional value of the by-product; and 4) the technology in the invention can be recycled and has no secondary pollution.

The invention relates to a sintering flue gas desulfurization combined coking coal gas deamination circulation cycling technology, which comprises the following steps: (1) removing sulfur dioxide in the sintering flue gas using ammonium sulfite solution as desulfurization agent to generate ammonium bisulfite solution; (2) remove ammonia in the coking coal gas using the ammonium bisulfite solution obtained in the step (1) as deamination agent to obtain ammonium sulfite solution, using part of the ammonium sulfite solution as desulfurization agent in step (2), and oxidizing other ammonium sulfite solution into ammonium sulfate solution; (3) evaporating the ammonium sulfate solution, crystallizing, separating and drying to obtain the ammonium sulfate product. A sintering flue gas desulfurization combined coking coal gas deamination cycling system comprise a sintering flue gas desulfurization system, a coking coal gas deamination system and a ammonium sulfate preparation system. The invention removes ammonia in the coking coal gas efficiently while removing SO2 from sintering flue gas, reduces the raw material cost of desulfurization and deamination at the same time.

There is disclosed a process for producing taurine by reacting 2-oxazolidinone with ammonium sulfite, or ammonium bisulfite, or a mixture of ammonium sulfite and ammonium bisulfite in an aqueous solution to form ammonium taurinate and ammonium bicarbonate. Taurine is obtained by decomposing ammonium taurinate to taurine and ammonia and recovered by solid-liquid separation.

The invention relates to a monotower ammonia desulfuration recovery method for removing aerosols in flue gas, which is characterized in that the flue gas desulfuration process is carried out in a combined desulfuration tower with a plurality of functions; the high-temperature flue gas enters from the side surface of the desulfuration tower; the lower part of the desulfuration tower is an oxidation section, the middle part thereof is a main absorbing section and the upper part thereof is a demisting section. In order to remove the SO2 aerosols possibly existing in the desulfuration process and reduce the entrainment of an ammonium sulfate solution in the flue gas (the entrainment of the ammonium sulfate solution refers to the amount of 10-35 percent (m/m) concentration of the ammonium sulfate solution contained in the desulfurated flue gas), a tail gas washing tower is additionally arranged in the rear of the desulfuration tower, and a high-flow nozzle is designed in the tail gas washing tower; and the flue gas departing from the desulfuration tower is washed by utilizing clear water, therefore, the entrainment of the ammonium sulfate solution in the flue gas is reduced, the ammonium bisulfate (ammonium bisulfite) aerosols are absorbed and dissolved, and the recovery rate of ammonium sulfate products is improved.

Provided are methods for the pretreatment of ligno-cellulosic biomass such as softwoods with bisulfite such as ammonium bisulfite without the need for exogenous acid. In one variation, a method of pretreating ligno-cellulosic biomass is provided including the following steps: a) providing ligno-cellulosic biomass; b) contacting the ligno-cellulosic biomass with a solution comprising bisulfite at an amount between 1 and 10% of a dry weight of the ligno-cellulosic biomass to form a slurry; c) heating the slurry to a first temperature of 150-210° C. for a first period of time to form a first mixture; d) cooling the first mixture to a second temperature of 100-200° C. to form a second mixture; and e) maintaining the second mixture at the second temperature for a second period of time to form pretreated ligno-cellulosic biomass; wherein the first temperature is higher than the second temperature.

There is disclosed a process for producing taurine from aziridine by (a) adding gaseous aziridine or a solution of aziridine to a solution of ammonium bisulfite, or ammonium sulfite, or a mixture of ammonium bisulfite and ammonium sulfite to form ammonium taurinate; (b) decomposing ammonium taurinate by heating and removing ammonia from (a) to obtain a crystalline suspension of taurine; and (c) separating taurine by means of solid-liquid separation.

The invention discloses a method for producing by-product cyclohexanone-oxime through flue gas desulphurization by an ammonia method. The method comprises the following steps: ammonia or ammoniacal liquor is taken as an absorbent, sulfur dioxide in flue gas is absorbed in a flue gas absorbing tower, then ammonium bisulfite is prepared; the ammonium bisulfite is subjected to a reaction with nitrite and sulfur dioxide to prepare hydroxylamine sulphate; and the hydroxylamine sulphate and cyclohexanone are subjected to a reaction by employing a counter current oximation mode to produce cyclohexanone-oxime. The method has the advantages that SO2-containig flue gas is discharged with a standard, a sulfur resource in the flue gas and an ammonia resource in a desulfurizer can be recovered, a cyclohexanone-oxime product which has the advantages of high additional value and large product market space can be produced, high grade resource utilization of the by-product can be enhanced, waste can be changed into valuables, and economic benefit of flue gas desulphurization by the ammonia method can be increased.

A preparation method for glyphosate comprises the steps as follows: oxydol is adopted for catalytic oxidation of a pmida raw material to obtain oxidation liquid, sulfide reductant with weaker reducibility is added into the oxidation liquid to consume excess oxydol in the oxidation reaction, then ferrous sulfate is added for reduction, and finally separation and drying are conducted so as to prepare the glyphosate; and the sulfide reductant with the weaker reducibility is any one or any combination of sodium sulfite, ammonium sulfite, potassium sulfite, ammonium bisulfite, sodium thiosulfate and sodium bisulfite. According to the method provided by the invention, the amount of the ferrous sulfate reductant is low, so as to save the raw material cost; the technical problem that the glyphosate prepared by the process in the prior art is yellowish is solved due to oxidation, reduction and other treatments in the method; meanwhile, the purity of the glyphosate prepared by using the method is high, the content of the glyphosate in solid powder is more than 96 percent, and the yield is more than 82 percent; and through the adoption of the method, the consumption of raw and auxiliary materials is lower, ammonia water, sulfuric acid and other raw materials are not used in the process.

A process for treating a gas comprising hydrogen suilfide and carbon dioxide by contacting the gas with a scrub solution comprising ammonium sulfite and ammonium bisulfite in a first contact zone to produce ammonium thiosulfate. The scrub solution can be formed in a second contact zone by contacting ammonia and hydrogen sulfide with an aqueous solution. The oxidation potential of the first contact zone effluent liquid can be controlled by modulating the amount of sulfur dioxide supplied to the second contact zone. Alternatively, the sulfite concentration of the first contact zone effluent can be measured with an infrared analyzer and the amount of sulfur dioxide supplied to the second contact zone modulated in response. Additionally, the amount of ammonia supplied to the second contact zone can be modulated in response to the pH in the second contact zone. The process can further comprise a solvent scrubber to remove carbon dioxide from the first contact zone overhead gas. A third contact zone can be included in the process to separate the hydrogen sulfite from the carbon dioxide in the solvent regenerator overhead gas.

The invention relates to a process and equipment for producing potassium sulfate compound fertilizer by integrally utilizing tail gas generated in sulphuric acid production, belonging to the technical field of fertilizer manufacture. The process comprises the following steps: washing sulphuric acid tail gas and chlorosulfonic acid tail gas with ammonia water; preparing ammonium sulfate by the generated ammonium bisulfite and ammonium sulfite; and producing the potassium sulfate by the prepared ammonium sulfite. The equipment for the process includes a reaction kettle which is communicated with a first washing tower and a second washing tower through a circulating pump and a pipeline, wherein the first washing tower and an ammonia vessel are connected with a sulphric acid tail gas exhaust device; and the second washing tower and the ammonia vessel are connected with a chlorosulfonic acid tail gas exhaust device. The process uses the ammonium bisulfite and the ammonium sulfite generated in the tail gas treatment of sulphuric acid production and chlorosulfonic acid, wherein the sulphric acid is used to decompose the sulfur dioxide generated by the ammonium bisulfite and the ammonium sulfite to reproduce sulphric acid, and the produced ammonium sulfate is applied to the compound fertilizer system for producing the compound fertilizer so as to reduce resource waste and environmental pollution.

The invention discloses a technology and a device for reducing drag of a desulfurization tower of a flue gas desulfurization system of a sintering machine. The method comprises the following steps ofpretreatment, reverse absorption, demisting, solution oxidizing, filtering, and process water treatment. The method has the beneficial effects that the flue gas entering the desulfurization tower is cooled and dedusted by a gas high-efficiency water cooling and dedusting device and a bag type deduster or an electric deduster, and two spraying assemblies are used for spraying and cooling, so that the temperature difference between flue gas and absorbing liquid is reduced, the separating rate of ammonia sulfate is reduced, and the blockage due to crystallizing in the tower is reduced; the absorbing rate of sulfur dioxide is improved, the emission amount of ammonium sulfite and ammonium sulfite aerosol along with flue gas is reduced, the loss of ammonia is reduced, and the concentration of escape ammonia is lower than 10mg/Nm<3>; the aerosol in the flue gas can be quickly and effectively removed, the quality of flue gas entering the desulfurization tower is greatly improved, the drag of the desulfurization tower is reduced, and the service life of the desulfurization tower is prolonged.

The invention relates to a gas treating process of generating ammonium thiosulfate by contracting a gas (1) comprising hydrogen suilfide and carbon dioxide with a scrub solution (2) comprising ammonium sulfite and ammonium bisulfite in a first contact zone (3). The scrub solution can be formed in a second contact zone (6) by contacting ammonia (8) and hydrogen sulfide (7) with an aqueous solution. The oxidation potential of the first contact zone effluent liquid can be controlled by modulating the amount of sulfur dioxide supplied to the second contact zone. Alternatively, the sulfite concentration of the first contact zone can be measured by an infrared analyzer and can be modulated in response to the amount of sulfur dioxide supplied to the second contact zone. Additionally, the amount of ammonia supplied to the second contact zone can be modulated in response to the pH in the second contact zone.