55results about How to "Less alkali consumption" patented technology

A process for extracting xylan from wooden fibre material features that under the catalysis of microwave, the alkali solution containing hydrogen peroxide in directly sued to treat raw material for performing extraction of xylane and bleaching it at same time. Its advantages are high speed, less consumption of alkali, and high extracting rate. The resultant xylan solution can be deposited in organic solvent or superfilted and dried to obtain light-color xylan product.

The invention relates to a method for preparing rare earth chloride from mixed rare earth concentrate or monazite concentrate and belongs to the field of hydrometallurgy. According to the method, the rare earth chloride with the rare earth leaching rate reaching 94.87-99.26% is prepared by controlling the alkali decomposing temperature, the reaction time and the reaction pressure of the mixed rare earth concentrate or the monazite concentrate in the high-pressure alkali decomposing process. The method has the beneficial effects that the mineral decomposing rate is high under the high-pressure condition, the decomposing temperature is reduced, the reaction time is shortened, and energy conservation and environment friendliness are achieved; caustic soda can be recycled, so that cost is reduced; no three-waste pollution is generated, and various valuable elements are comprehensively recycled; and the technological process is short, and the method is suitable for industrial production.

The invention provides a novel dual-alkali flue gas desulfurization method and flue gas desulfurization system, and relates to the technical field of flue gas purification. The method comprises the following steps of absorbing SO2 in flue gas to generate an absorption solution containing sodium sulfite and sodium bisulfite by taking sodium hydroxide or sodium carbonate as an absorbent, enabling the absorption solution to enter a regenerated reactor, regenerating the absorption solution in the regenerated reactor by using magnesium oxide or magnesium hydroxide, performing precipitation separation by virtue of a solid-liquid separator, enabling sodium sulfite or sodium hydroxide formed by regeneration to return to a desulfurization tower for flue gas absorption for recycling, enabling magnesium sulfite precipitates obtained by solid-liquid separation to enter a desulfurization product treatment system, and directly discharging magnesium sulfite or preparing magnesium sulfate. According to the method and the system, a sodium and magnesium dual-alkali method is adopted for flue gas desulfurization, so that a good desulfurization effect is achieved, oxidation is not required by the system, accumulation of sodium sulfate is avoided, and the system can run for a long time; moreover, the materials in the system can be regenerated and recycled, therefore alkali consumption is reduced, and the cost is reduced.

The invention discloses a method for preparing idesia polycarpa edible vegetable oil by an immobilized enzyme and hot brine treatment process, belonging to the field of food. The method comprises the following steps: raw oil degumming, acidity reduction by immobilized enzyme, alkali refining, water washing, debitterizing by hot brine, and vacuum deodorization. The invention is characterized in that the immobilized enzyme is utilized to treat degummed oil, thereby lowering the acidity and reducing the alkali consumption and the amount of the formed saponin; the hot brine is utilized to treat the alkali-refined oil and thoroughly remove the bitter principles from the oil to finally obtain the high-quality edible vegetable oil, thereby saving the removal time and the water consumption; and meanwhile, the invention has the advantages of simple technological process, mild operating conditions, low requirements for equipment, high safety and environmental protection, and has wide application prospects in the production of idesia polycarpa edible oil.

The invention discloses a method for producing metallurgy-grade alumina by taking pulverized fuel ash and recycled ammonium salt as raw materials. The method comprises the following steps: (1) preparing materials; (2) roasting; (3) dissolving; (4) crystallizing; (5) carrying out a liquid-solid ammonolysis reaction; (6) grinding and removing sulfur; and (7) performing low-temperature Bayer aluminum production. The method disclosed by the invention has the advantages that an aluminum salt ammonolysis method suitable for strong acid and weak base is adopted, namely liquid-solid or gas-solid ammonolysis is performed, the production efficiency is improved by over 60 percent compared with that a liquid-liquid ammonolysis method, the process conditions of the ammonolysis method are optimized, optimal process parameters are determined, the obtained product, namely crude aluminum hydroxide, is easy to filter and wash, the model selection of equipment is simple, and industrial mass production can be realized.

The invention discloses a recovery processing method of amino C acid acid-wastewater, which comprises the following steps: adding finite proportion extractant into waste water; shocking sharply; mixing fully; stewing; layering; sharing oil phase and water phase; extracting most of organic matter into oil phase; removing oil phase; adding into finite quantity queous alkali; proceeding strip; getting regenerate extractant; cycling using in craft; separating out organic matter from waste water; forming strip water phase; getting the reclaiming sulphuric acid; making total clearance of acid waste water CODCr reach above 93% and reclaiming sulfuric acid density at 560g.L-1; setting reclaiming rate of sulfuric>92%.

The preparation process of solid potassium ferrate includes the following steps: introducing chlorine into purified waste alkali solution to prepare hypochlorite solution; adding ferric nitrate into the solution to prepare potassium ferrate solution; adding solid potassium hydroxide, dissolving and filtering to obtain coarse potassium ferrate product; washing coarse potassium ferrate product with potassium hydroxide solution; filtering to obtain re-crystallized potassium ferrate product; washing with organic solvent and vacuum drying to obtain stable solid potassium ferrate product; collecting all the filtrate and treating for reuse. The present invention has the circulated utilization of waste alkali solution, low cost and less environmental pollution.

The invention relates to uniform ultra-microporous activated carbon for gas separation and a preparation method of the uniform ultra-microporous activated carbon. According to the technical scheme of the preparation method, mixing semi-coke with KOH in a mass ratio being 1: (0.01-0.2), adding water and an activating aid to impregnate the mixture for 1-36 h; increasing the temperature to 800-950 DEG C in a programmed manner under N2 protection, controlling thermal decomposition, and introducing water for activation of part of steam for 0.5h-1.5h; finally, washing the mixture with acid and water until the mixture is neutral to obtain the uniform ultra-microporous activated carbon. The pore size is distributed centrally between 0.45 and 0.55 nm, the pores belong to ultra-micropores and have microporosity of 70% or more, and the adsorption capacity of hydrogen is 77cm<3>/g or higher. The semi-coke is taken as a raw material, low in price and low in energy consumption and needs not to be carbonized; an activation method integrates KOH impregnation pretreatment and activation of part of steam, little KOH is consumed, and the activation method has the characteristics of being low in cost and pollution, helpful for reducing corrosion of equipment and the like. The activated carbon prepared with the method has the characteristics of uniform pore size distribution, extremely rich ultra-microporous structure and the like, and can be used in gas separation fields such as pressure swing adsorption hydrogen making or hydrogen storage and the like.

The invention discloses a method for concentrating wastewater containing hydrochloric acid by two-stage electrodialysis. The method includes that first a waste liquid containing about 1% hydrochloricacid is concentrated by first-stage electrodialysis, the concentration of the hydrochloric acid in the concentrated liquid can reach 3% or more, and the hydrochloric acid can be directly reused; the concentration of the hydrochloric acid in a desalinated solution can be reduced to less than 0.2%; then the desalinated solution of the first-stage electrodialysis can be further desalinated and concentrated by second-stage electrodialysis to reduce the concentration of the hydrochloric acid to less than 0.05%, meanwhile the concentration of the hydrochloric acid in the concentrated solution can reach more than 1%, and the concentrated liquid is returned to the first-stage electrodialysis as a concentration chamber initial solution for recycling. The method is simple in operation, economical and environmentally friendly. The low concentration hydrochloric acid in the waste liquid can be directly concentrated and reused, and the concentration of the hydrochloric acid in the desalinated solution is very low, and the desalinated solution can be discharged by simply adding a small amount of alkali for neutralization, so that treatment of the wastewater containing the low-concentration hydrochloric acid can be achieved.

The invention relates to reduction smelting slag and application of the reduction smelting slag to reduction smelting of coarse antimony oxide, and belongs to the field of nonferrous metallurgy. The designed reduction smelting slag comprises, by mass, 20-40 parts of SiO2, 20-40 parts of FeO, 5-20 parts of CaO and 5-25 parts of Na2O. During reduction smelting of the coarse antimony oxide, the set reduction smelting slag is supplemented, the temperature ranging from 900 DEG C to 1,200 DEG C is kept for 30-120 min, coarse antimony, glass slag, smoke and flue gas can be generated, the coarse antimony and the slag are independently discharged after settling separation, the smoke is subjected to powder returning treatment, and the flue gas is exhausted after being purified. The design technology has the beneficial effects that the smelting temperature is low, the antimony content of the slag is small, the antimony direct recovery rate is high, and the powder returning amount is small; and large-scale industrial application is facilitated.

The invention provides a method for eliminating ammonia inhibition in an anaerobic fermentation process of livestock and poultry excrement. According to the method, a struvite crystallization and sedimentation technology is used for detecting the concentration of NH<4+> in an ammonia inhibition system under the conditions that the pH value is 7-9, and the mass concentration ratio of volatile fatty acid to total inorganic carbon is less than 0.4; magnesium salt and phosphorus salt are added into a livestock and poultry excrement fermentation reaction system according to a molar ratio of the NH<4+> to Mg<2+> to PO4<3-> being equal to 1: 1: 1; the concentration of ammonia nitrogen is reduced to about a concentration value of the fermentation process without ammonia inhibition. The method for eliminating the ammonia inhibition in the anaerobic fermentation process of the livestock and poultry excrement is established by studying the influence factors of an ammonium magnesium phosphate reaction in the inner environment of an anaerobic fermentation tank and the self-limiting factors of the reaction. The method is simple in technology; furthermore, struvite precipitation produced in the reaction is slow release fertilizer, and not only can eliminate the ammonia nitrogen inhibition, but also can recover nutrients such as nitrogen and phosphorus, so that the operating cost is lowered.

The invention discloses a device and a method for carrying out low-concentration SO2 flue gas desulfurization by utilizing a fuzzy alkali-feeding method. The device comprises a desulfurization tower, a main alkali-feeding valve, a fuzzy alkali-feeding valve, a reflowing valve, a liquid discharging valve, a water feeding valve, a primary circulating system pH (Potential of Hydrogen) detector, a secondary circulating system pH detector, a liquid level detector, a flue gas outlet SO2 concentration analyzer, a DCS (Distributed Control System) switching system, a signal isolator and an intelligent fuzzy controller. The point is that alkali-feeding desulfurization is carried out through logic control by utilizing the intelligent fuzzy controller; different alkali-feeding manners can be realized by alkali-feeding controlling through the DCS switching system according to different working conditions; the alkali-feeding controlling is more accurate, and the desulfurization effect is remarkable; meanwhile, consumed alkali in a tail gas control process is saved; a technological process is simple, and the operation is reliable; when normal production is performed, whole-time standard reaching of tail gas exhausting can be effectively ensured. Meanwhile, the labor intensity of maintenance personnel is reduced, and operating personnel conveniently control the device; a condition that tail gas emission exceeds standards, caused by the fact that the operating personnel are careless and the control is not in time, is eliminated.

The invention discloses an anti-corrosion and anti-scaling integrated control system and method for thermal equipment of a power plant. According to the system, an economizer inlet pipeline is provided with an online conductivity meter, and a deaerator inlet, an economizer inlet and a high-pressure heater drainage pipeline are each provided with an online dissolved oxygen meter. When the measuredvalue of the economizer inlet on-line dissolved oxygen meter is lower than the lower limit of a set value or higher than the upper limit of the set value, a PLC increases or decreases the ammonia adding amount on the condensed water fine treatment outlet main pipe, and when the measured value of the economizer inlet on-line conductivity meter is lower than the lower limit of the set value or higher than the upper limit of the set value, the PLC increases or decreases the oxygen adding amount of feed water on a descending pipe of the deaerator, so that the dissolved oxygen and the direct conductivity at the economizer inlet are made to be within the optimal control range. And when the high-pressure heater hydrophobic dissolved oxygen is lower than the lower limit value or higher than the upper limit value, the PLC increases or decreases the oxygen adding amount on the high-pressure heater hydrophobic pipeline, so that the high-pressure heater hydrophobic oxygen content is made to be within the control range. And integrated control over corrosion prevention and scale prevention of the thermal equipment is achieved.

The invention discloses a sewage treatment process and a sewage treatment system thereof. The sewage treatment system comprises a primary sedimentation/adjustment tank, an up-flow type filter, a preaeration tank, an IFAS-MOX reactor, a secondary sedimentation tank and a clean water basin, wherein a sewage inlet trough is arranged on one side of the primary sedimentation/adjustment tank; a thick-thin grid is arranged in the sewage inlet trough; a micropore aerator pipe is arranged in the preaeration tank; and one end of the micropore aerator pipe communicates with a fan located on the outer side of the preaeration tank. According to the sewage treatment process and the sewage treatment system thereof provided by the invention, by utilizing the advantages of difficulty in blocking, fast filter speed and easiness in cleaning of the up-flow type filter, sewage is pretreated; by utilizing the advantages of a biofilm technology and an activated sludge technology in the IFAS-MOX reactor, without increasing the sludge concentration, the microbial population density is improved, and the sludge sedimentation performance is improved; through the dissolved oxygen gradient change, the commensalism of nitrosobacteria and anaerobic ammonium oxidation bacteria is realized, and a sewage nitrogen and phosphorus removal effect is improved. A carbon source in sewage is effectively utilized, the oxygen utilization ratio is high, the energy consumption is low, and a nitrogen and phosphorus removal effect is good.

The invention relates to a high-concentration N-phenylmaleimide reaction liquid post-treatment process, which is uniquely characterized in that the reaction liquid is sequentially subjected to water washing and neutralization, and the obtained liquid is subjected to solvent removing in a rotary evaporator to obtain the product without re-crystallization. The process comprising: adding water and a solvent mixture to a N-phenylmaleimide reaction liquid according to a certain ratio in a mixing manner, stirring, cooling, separating to obtain a water layer and an oil layer, carrying out water washing on the water layer, cooling the washed water layer, and carrying out vacuum suction filtration to obtain a maleic anhydride (short for maleic anhydride) by-product solid and water, wherein the maleic anhydride is used as the reaction raw material so as to be continuously used for the N-phenylmaleimide reaction step, and the water is continuously used for the water washing step; carrying out water washing on the oil layer, separating the oil layer to obtain a water layer and an oil layer, and distilling the neutralization water layer to obtain water and trace residue, wherein the water is continuously used, and the residue is treated; and adding the neutralization oil layer to the rotary evaporator, and evaporating the solvent to obtain the N-phenylmaleimide finished product with the purity of more than or equal to 99.25%. According to the present invention, the yield of the whole post-treatment process can exceed 97.5%, no wastewater is generated, and the process is environmental protection.

The invention discloses an industrialized preparation method of 2-carboxyl-3-naphthalene formic acid. The 2-carboxyl-3-naphthalene formic acid is prepared by feeding raw materials into a first reaction tower, a carboxylation reaction tower, a second reaction tower, a neutralization reaction tower, an acidification reaction tower, a filter pressing reaction tower, a refined filtration reaction tower, a hydration reaction tower, a reaction tower and a finished product storage tower in turn. The 2-carboxyl-3-naphthalene formic acid is high in product purity up to over 98.89%, high in smelting point up to 220 DEG C, low in crystallization rate less than 3% and is yellowish-brown.

The invention relates to the field of chemical synthesis, in particular to a DSD acid preparation method. The DSD acid preparation method includes the steps that methylbenzene is subjected to sulfonation, purification and separation to obtain OTS, wherein the byproduct is PTS; OTS is subjected to mixed acid nitration to obtain PNTS; PNTS is subjected to chlorine oxidative condensation to obtain DNS; DNS is subjected to catalyzed hydrogeneration reduction to obtain the high-quality target product, namely DSD acid which can be directly used for synthesizing a fluorescent whitening agent. The synthesis method greatly reduces dangerousness of the process, greatly reduces generation of harmful byproducts and waste, particularly, does not generate a lot of carcinogenic intermediate, namely ortho-nitrotoluene, completely solves the nitration safety problem of the old technology, and has the advantages of being simple in step, high in yield and the like.