4192 results about "Filter cake" patented technology

Methods of operating candle filter systems for removing solids from MEG recovered from drilling fluids include passing an MEG rich stream to a candle filter system comprising a plurality of candle filter units in parallel, determining a concentration of TDS in the MEG rich stream, determining whether to operate the candle filter system in a low TDS mode or a high TDS mode based on the concentration of TDS the MEG rich stream, filtering the MEG rich stream in the plurality of candle filter units to produce a filtrate and a filter cake, determining to conduct a cleaning cycle of the candle filter units based on a pressure differential, and conducting a cleaning cycle to remove the filter cake from the outer surfaces of the filter candles. The cleaning cycle is modified to improve removal of solids from the filter candles of the candle filter units.

The invention provides a plate-and-frame filter press, and belongs to the technical field of plate-and-frame filter presses. Comprising a filter press body, the driving assembly has reciprocating displacement along the length direction of the filter press body; the scraper assembly is connected to the filter press body in a sliding manner; the scraper assembly at least comprises a scraper; an included angle a is formed between the scraper and the gravity direction; the included angle a is increased or decreased according to the weight b of the filter cake; the moving distance L of the previous plate frame driven by the driving assembly is increased or decreased under the control of the weight b of the filter cake. The included angle of the scraping plates is adjusted according to the weight of a filter cake, smooth stripping of the filter cake is ensured, particularly, the filter cake with high water content and high weight can be scraped cleanly, residues are avoided, and abrasion of equipment is reduced by reducing unnecessary displacement distance and reducing friction between the guide rail and the plate frame.

The invention discloses high-purity hafnium oxide and a preparation method thereof, and relates to the technical field of hydrometallurgy. The preparation method of the high-purity hafnium oxide comprises the following steps: crushing a hafnium oxide raw material to obtain hafnium oxide powder; sequentially carrying out alkali fusion, water immersion and filtration treatment on the hafnium oxide powder to obtain a hafnium hydroxide filter cake; dissolving the hafnium hydroxide filter cake in a sulfuric acid solution to obtain a hafnium sulfate solution; adding sodium sulfate into the hafnium sulfate solution to obtain hafnium-containing double salt; dissolving the hafnium-containing double salt in a sulfuric acid solution, heating, evaporating, cooling and crystallizing to obtain hafnium sulfate crystals; dissolving the hafnium sulfate crystal in concentrated hydrochloric acid to obtain a hafnium oxychloride solution, heating, evaporating, cooling and crystallizing to obtain a hafnium oxychloride crystal; dissolving the hafnium oxychloride crystal in pure water, adding an oxalic acid solution, and precipitating to obtain hafnium oxalate; and calcining hafnium oxalate to obtain high-purity hafnium oxide. The preparation method of the high-purity hafnium oxide is green, environment-friendly, simple and efficient.

The invention provides pseudo-boehmite and a preparation method thereof, and the method comprises the following steps: carrying out a neutralization reaction on sodium metaaluminate and an acidic aluminum salt to generate an amorphous precipitate, so as to obtain first slurry; filtering the first slurry, and pulping a filter cake obtained by filtering to obtain second slurry; and adjusting the pH value of the second slurry to a preset pH value by using an alkaline additive so as to age the second slurry, thereby obtaining the pseudo-boehmite. The prepared pseudo-boehmite meets the following indexes: the pore volume is greater than 1.2 ml / g, and the impurity content of acidic components is lower than 0.5 wt%.

The invention provides a low-cost preparation method of high-performance titanium-doped iron phosphate, and relates to the technical field of batteries. The low-cost preparation method comprises the following steps: S1, respectively preparing a phosphoric acid solution, a hydrogen peroxide solution, a phosphorus salt solution and a ferrite solution; s2, adding titanium sulfate into the ferrite solution to obtain an iron-titanium mixed solution; s3, directly adding ammonia water and a hydrogen peroxide solution into the phosphorus salt solution to obtain a phosphorus-oxygen mixed solution; s4, the iron-titanium mixed solution is heated, the phosphorus-oxygen mixed solution is put into the iron-titanium mixed solution, and slurry A is obtained; s5, obtaining a filter cake A; s6, adding pure water and a phosphoric acid solution, and heating to obtain slurry B; s7, obtaining anhydrous iron phosphate; the synthesized iron phosphate is compact and compact in morphology, internal pore channels of primary particles are still rich, the compaction density of the lithium iron phosphate material obtained through grinding and sintering reaches 2.613 g / cc, the 0.1 C discharge capacity can still reach 156.35 mAh / g, and the 1C discharge capacity reaches 131.47 mAh / g.

The invention provides a single-crystal-like dense iron phosphate material and a preparation method thereof.The iron phosphate material is prepared through the following steps that S1, a certain amount of pure water is added into a reaction kettle for bottoming, a ferrite solution and a phosphorus salt solution are added at the temperature of 30-60 DEG C, and ferrous phosphate slurry A is obtained; s2, carrying out solid-liquid separation and washing treatment on the ferrous phosphate slurry A to obtain a ferrous phosphate filter cake; s3, pulping the ferrous phosphate filter cake with pure water, uniformly stirring, transferring into a reaction kettle, continuously stirring, heating, mixing a phosphoric acid solution and a hydrogen peroxide solution, and adding to obtain white slurry B; and S4, carrying out solid-liquid separation, washing treatment and flash evaporation drying on the white slurry B to obtain iron phosphate dihydrate, and calcining the iron phosphate dihydrate to obtain the monocrystal-like dense iron phosphate material with the high iron-phosphorus ratio. When the iron phosphate provided by the invention is matched with conventional iron phosphate to prepare lithium iron phosphate, the quantity ratio of small-particle lithium iron phosphate can be effectively controlled.

The invention discloses a method for preparing asphalt-based porous carbon based on an MgO template, and belongs to the technical field of porous carbon, nano MgO and deionized water are mixed and placed in a synthesis kettle, hydrothermal synthesis is performed at 180 DEG C for 2 h, suction filtration and drying are performed, a dried filter cake is crushed and calcined, and porous flaky MgO is obtained; adding the asphalt solution into the MgO suspension, stirring, drying to obtain brown powder, transferring the brown powder into a corundum crucible, putting the corundum crucible into a tubular furnace, calcining to obtain a carbonized C / MgO composite material, and washing the carbonized C / MgO composite material with a diluted hydrochloric acid solution and deionized water to obtain a carbon material sample recorded as AC-75. Pouring the porous carbon material PCs and KOH into a mortar, fully grinding, mixing and calcining to obtain an activated product, pickling and washing the product to be neutral, and drying to obtain the porous carbon material PCs. The raw materials selected by the method are asphalt and flake magnesium oxide which are stable in performance, low in price, large in amount and easy to obtain, a magnesium source can be recycled, environmental protection is achieved, and resources are saved.

The invention provides a method for precipitating nickel and cobalt in a solution containing nickel and cobalt and a cobalt nickel hydroxide product. The method comprises the following steps: step S100, carrying out a seed crystal pretreatment reaction on a nickel-cobalt-containing solution by adopting first nickel-cobalt precipitation underflow to form pretreated nickel-cobalt ore pulp; step S200, adding an alkaline precipitation inducer into the second nickel-cobalt precipitation underflow or the first nickel-cobalt precipitation overflow to carry out alkali conversion reaction to form alkali conversion crystal mush; s300, the pretreated nickel-cobalt ore pulp and alkali conversion crystal mush are continuously introduced into a reactor for a nickel-cobalt precipitation reaction, and nickel-cobalt precipitated ore pulp is obtained; step S400, continuously performing dense separation treatment on the ore pulp subjected to nickel-cobalt precipitation; s500, the third nickel-cobalt precipitation underflow is filtered and washed in sequence, a nickel-cobalt hydroxide product is obtained, and the problems that in the prior art, when nickel and cobalt are precipitated through a nickel-cobalt-containing solution, MHP is small in particle size and not prone to sedimentation, the water content of a filter cake is high, or the precipitation rate is poor, and the magnesium content is high before technical improvement are solved.

The invention provides a preparation method of an iron phosphate material uniformly doped with a titanium element. The preparation method comprises the following steps: S1, respectively preparing a phosphoric acid solution, a phosphorus-oxygen mixed solution, a ferrous sulfate salt solution and a titanium salt solution; s2, adjusting the pH value of the ferrous sulfate salt solution to 1.0-2.5, adding the titanium salt solution and the phosphorus-oxygen mixed solution in a two-strand simultaneous adding manner, uniformly stirring, and reacting for 25-35 minutes at the temperature of 30-60 DEG C to obtain slurry A; s3, filtering and washing the slurry A to obtain a filter cake B; s4, adding water into the filter cake B, pulping, adding a phosphoric acid solution, heating, and preserving heat to obtain white slurry B; s5, filtering, washing and drying the white slurry B to obtain titanium-doped iron phosphate dihydrate, and calcining the iron phosphate dihydrate to obtain anhydrous iron phosphate; according to the invention, the crystal structure of the iron phosphate is improved by doping the titanium element, short-range preparation of the iron phosphate is realized, uniform doping of the element is ensured, the production period is shortened, and the complexity of the process is obviously reduced.

The invention belongs to the technical field of filtering equipment, and particularly relates to a candle filter which comprises a filtering tank, filter element pipes are arranged in the filtering tank and connected with a liquid collecting pipe, a scraping plate is arranged on the inner wall of the filtering tank in a sliding mode, a plurality of cake scraping mechanisms are arranged on the scraping plate, each cake scraping mechanism is provided with a plurality of scraping plate holes, and the scraping plate holes correspond to the filter element pipes in a one-to-one mode. The diameter of the scraper hole is larger than the outer diameter of the filter element pipe, the filter element pipe penetrates through the scraper hole, a scraper assembly is arranged in the scraper hole, a first liquid inlet is formed in the bottom of the filtering tank, a second liquid inlet is formed in the upper end cover, and the first liquid inlet is connected with a stock solution tank and a waste liquid tank through a pipeline provided with a first electric control valve; and the second liquid inlet is connected with the stock solution tank and the waste liquid tank through a pipeline provided with a second control valve. According to the candle filter provided by the invention, the scraper assembly can scrape off the outer wall of the filter cake layer in the filtering process, so that the filter cake layer is always in the optimal filtering effect range, the filtering effect is ensured, and meanwhile, the filtering efficiency is also improved.

The invention discloses alkali-activated porous carbon and a preparation method thereof, and relates to the field of new material preparation, and the preparation method comprises the following steps: uniformly mixing matrix carbon and a strong alkaline substance according to a mass ratio to obtain a mixed material, putting the mixed material into a crucible, and carrying out high-temperature calcination and cooling on the mixed material under the protection of an inert atmosphere; washing and filtering the mixed material subjected to high-temperature calcination for 3-6 times by using deionized water; after washing is completed, strong acid is used for soaking; and after soaking, filtering to obtain a mixed material filter cake, soaking the mixed material filter cake in ionized water, repeatedly washing, and drying until the pH value is neutral. The porous carbon material is prepared through alkali activation, the preparation steps are simple, expensive auxiliary equipment is not needed, the cost is low, preparation is safe, and the method has extremely high economic benefits and large-scale application prospects.

The invention discloses a preparation method of a lithium manganese iron phosphate precursor, which comprises the following steps: mixing a manganese source and an iron source according to the molar ratio of Mn < 2 + > to Fe < 2 + > of (1.5-4): 1, adding water to prepare a manganese and iron ion mixed solution with the total concentration of Mn < 2 + > and Fe < 2 + > of 1-2mol / L, then dropwise adding the manganese and iron ion mixed solution and a precipitator into a base solution at the same time to obtain a reaction mixed solution, carrying out heat preservation and aging on the reaction mixed solution, then carrying out solid-liquid separation to obtain a filter cake, sequentially washing, drying and calcining the filter cake to obtain ferromanganese oxide, and then preparing a lithium iron manganese phosphate material by taking the obtained ferromanganese oxide as a lithium iron manganese phosphate precursor; according to the method, the soluble manganese source and the iron source are adopted for coprecipitation, and the manganese-iron ratio, the reaction rate, the pH and the reaction temperature are controlled, so that stable manganese-iron oxide with uniformly mixed manganese and iron is prepared, the stability of the further prepared lithium manganese-iron phosphate material is higher, and the electrochemical performance of the lithium manganese-iron phosphate material is effectively improved.

The invention discloses a Ca / Mg-based modified biochar material and a preparation method and application thereof, and the preparation method comprises the following steps: pretreatment: drying a biomass material shaddock peel, crushing, sieving, washing and drying, then carrying out acid leaching activation, washing again and drying to obtain high-activity biomass powder for later use; dipping modification: fully mixing the high-activity biomass powder obtained in the pretreatment step with CaO and MgO, adding distilled water, dipping under heating and stirring conditions, then carrying out solid-liquid separation, washing a filter cake for multiple times, freeze-drying, and sieving to obtain an intermediate product; the intermediate product is calcined, naturally cooled, washed and dried, and the Ca / Mg-based modified bimetallic modified charcoal material is obtained and can be applied to adsorption of phosphate in a wastewater solution as an adsorbent. The preparation method is simple, the raw materials are easy to obtain, the cost is low, the material stability is good, the pH adaptability is good, the adsorption effect is good, and the method is suitable for water environments with more complex pollution factors.

The invention relates to the technical field of tailing mud treatment, and discloses a solid-liquid separator for treating tailing mud, which comprises a support frame, the top of the support frame is fixedly provided with a vertical plate I and a vertical plate II, the outer wall of the vertical plate II is fixedly provided with a fixed seat, and the top of the fixed seat is fixedly provided with a central control box; a cross beam is fixedly assembled between the first vertical plate and the second vertical plate, a sliding groove is formed in the outer wall of the cross beam, a filter plate is arranged on the outer wall of the cross beam, a circular groove is formed in the inner wall of the filter plate, and a solid-liquid separation assembly is arranged on the inner wall of the circular groove. An electric telescopic rod II is started under the control of a weighing display instrument, so that an arc-shaped plate can lift a lapping block to move up and down, a filter plate can perform high-frequency vibration, a filter cake can quickly fall off from the filter plate, discharging is more thorough, meanwhile, the cleanliness of equipment is improved, and the device is high in discharging speed and convenient to use. And the influence of filter cake residues on the next filtering process can be effectively avoided, and the discharging efficiency is improved.

The invention relates to the technical field of sulfur-iodine circulating hydrogen production, in particular to a thermochemical iodine-sulfur-barium circulating hydrogen production process and a thermochemical iodine-sulfur-barium circulating hydrogen production system, which comprises the following steps: reacting excessive Ba < 2 + > with sulfuric acid in a Bunsen reaction product to obtain barium sulfate so as to obtain a first reaction mixed solution containing HI, BaSO4, H2O, BaI2 and a small amount of unreacted I2; sequentially carrying out cyclone separation, liquid removal and filter pressing to obtain a barium sulfate filter cake and a second mixed solution containing HI, H2O and BaI2; the method comprises the following steps: crushing a barium sulfate filter cake, performing high-temperature decomposition, returning gas generated by decomposition to participate in Bunsen reaction, and dissolving BaO generated by decomposition into Ba < 2 + >; and reboiling the second mixed solution to obtain hydrogen iodide steam, cooling a product obtained by decomposing the hydrogen iodide steam, carrying out gas-liquid separation to obtain hydrogen, and returning liquid obtained by gas-liquid separation to participate in the Bunsen reaction of the next cycle. Barium circulation is introduced, the process is simplified, the dosage of elemental iodine is reduced, and the cost is low.

The invention provides a method for synthesizing 1, 2-bis (4-vinyl phenyl) ethane, which comprises the following steps: adding a first solvent, methyl triphenyl phosphine halide and strong alkali into a reaction flask, and uniformly stirring to obtain a first mixed solution; heating the first mixed solution and carrying out reflux reaction for 1 hour; dropwise adding a 1, 2-bis (p-formaldehyde phenyl) ethane solution until the reflux reaction is finished to obtain a second mixed solution; reducing the temperature of the second mixed solution to room temperature, and adjusting the pH value of the second mixed solution to obtain a first solution; layering the first solution, and taking an organic layer; adding a polymerization inhibitor into the organic layer to obtain a second solution; concentrating the second solution to obtain a 1, 2-bis (4-vinyl phenyl) ethane crude product; adding a poor solvent into the crude product, stirring and crystallizing; filtering the crystal to obtain a filter cake, adding a second solvent into the filter cake, and washing and drying the filter cake to obtain 1, 2-bis (4-vinyl phenyl) ethane; the method for synthesizing the BVPE is simple and low in raw material cost, and the synthesized BVPE is high in purity and free of product isomeride.

The invention relates to a process for recycling and regenerating a waste lithium iron phosphate positive electrode material by using a specific chelating agent. The method comprises the following steps: carrying out heat treatment on a waste lithium iron phosphate positive electrode material, putting separated waste lithium iron phosphate powder into a ball milling tank, adding organic acid and a chelating agent, and carrying out ball milling; after the ball milling is finished, adding hydrogen peroxide, uniformly stirring and mixing, adjusting the pH value to 2-3 by using nitric acid, and filtering to obtain a filter cake which is iron phosphate; adding saturated sodium carbonate into the filtrate, precipitating, and recovering lithium carbonate; putting the iron phosphate, the lithium carbonate, the iron source, the lithium source and the phosphorus source in the step S3 into a ball mill for ball milling, and performing high-temperature solid-phase sintering after ball milling to obtain a regenerated lithium iron phosphate material; the chelating agent disclosed by the invention is prepared from (9ci)-2-(2-propenyl)-1-cyclopentene-1-carboxylic acid, 2-mercaptobenzimidazole carboxylic acid, an ethylene boric anhydride pyridine complex and potassium persulfate. The regenerated lithium iron phosphate material prepared by the method has excellent electrochemical performance.

A method includes: introducing a breaker composite into a subsurface formation, the breaker composite having a shell encapsulating a core comprising a breaker; breaking or degrading the shell of the breaker composite to release the breaker; and reacting the released breaker with a component of a filter cake, a scale, or a combination thereof thereby removing the filter cake, the scale, or a combination thereof.

The invention belongs to the technical field of denitration catalyst preparation, and discloses a meerscham-TiO2 composite carrier loaded manganese cerium medium and low temperature denitration catalyst and a preparation method and application thereof, the preparation method comprises the following steps: (1) mixing meerschaum and nitric acid, then heating and stirring for reaction, then carrying out suction filtration and washing, and drying to obtain a meerschaum-TiO2 composite carrier loaded manganese cerium medium and low temperature denitration catalyst; after the treated sepiolite is drained, drying and screening are conducted, and nitric acid acidified sepiolite is obtained; and (2) mixing the meerschaum acidified by nitric acid and TiO2, then adding the manganese source precursor solution into the acidified meerscham-TiO2, then dipping and stirring, dropwise adding a potassium permanganate solution into the solution, then adding a cerium nitrate solution, stirring and then carrying out suction filtration, drying, grinding and screening the obtained filter cake, and then calcining to obtain the catalyst. According to the invention, the acidified sepiolite and TiO2 are compounded, so that complementary advantages of the two carrier materials are realized, and the obtained catalyst not only has good denitration efficiency, but also can significantly reduce the production cost.

The preparation method comprises the following steps: S1, preparing a phosphoric acid solution, a hydrogen peroxide solution, a Ti salt, a phosphor salt solution and a ferrite solution; s2, Ti salt and the ferrite solution are mixed, and a titanium iron salt solution is obtained; mixing the phosphoric acid solution and the phosphorus salt solution to obtain a phosphorus source solution; s3, adding the titanium iron salt solution into a reaction kettle, and adding the hydrogen peroxide solution; s4, adding the phosphorus salt solution into the reaction kettle to obtain yellow slurry; s5, after the color of the slurry is heated to be white, white slurry is obtained; s6, carrying out solid-liquid separation on the white slurry to obtain an iron phosphate dihydrate filter cake; and S7, drying and calcining the iron phosphate dihydrate filter cake to obtain the Ti-doped battery-grade anhydrous iron phosphate. The titanium-doped iron phosphate is firstly prepared by a one-step method, the pH value of the reaction system is controlled by controlling the molar ratio of the iron element to all phosphorus elements in total phosphorus, ammonium phosphate and phosphoric acid in the reaction system, and the retention of the Ti element in the finished product and the regulation and control of the iron-phosphorus ratio in a specified range are ensured.

The invention provides three-stage extrusion type coal slime filter pressing equipment and a working method. The filter pressing equipment structurally comprises a thrust plate, a filter plate, filter cloth, a cross beam, a pressing plate, a pressing hydraulic system, a sealing unit, a feeding unit, a control unit and the like; columnar protruding structures arranged in an array mode are arranged on the outer surface of the filter plate, and each columnar protruding structure is in the structural form that a cone and a semicircle are combined. According to the requirements of the size and the dehydration rate of the filter plate, the columnar bulge structures are arranged on the surface of the filter plate by adopting a topological optimization method, so that the dehydration rate of the coal slime is improved, and the separation of a filter cake is facilitated; the pressing plate is of a sectional structure and is divided into three sections from left to right, and each section is connected with piston rods of the corresponding three hydraulic cylinders and corresponds to a three-stage extrusion working mode. And when the previous-stage extrusion pressure reaches 40% of the threshold pressure, the next-stage extrusion procedure is started. 40% of the extrusion threshold pressure can be set to ensure that the first two-stage extrusion is not finished when the third-stage extrusion process is started, so that the optimal extrusion mode of three-stage simultaneous extrusion is formed, the coal slime dehydration rate is increased to the greatest extent, and the filter pressing effect is improved. By adopting the three-stage extrusion mode, the dehydration process of each sub-area can be freely, flexibly and independently controlled, the toothpaste extrusion type collaborative filter pressing effect is achieved, the coal slime dehydration rate is higher, and the filter pressing effect is better.

The invention discloses a self-cleaning plate-type filter press for mother liquor purification in the field of filtering equipment, the self-cleaning plate-type filter press comprises a frame body and an extrusion assembly, the frame body comprises two guide rails arranged in parallel, the extrusion assembly comprises a plurality of filter pressing plates located between the two guide rails, and the filter press further comprises a shaking mechanism and a flushing mechanism; the two shaking mechanisms are arranged on the two guide rails respectively, each shaking mechanism comprises a sliding block and a driving assembly for driving the sliding block to slide on the guide rails, and the sliding block is provided with a lifting assembly for lifting the filter pressing plate after the filter pressing plate is jacked up; the flushing mechanism comprises a door-shaped support and a telescopic assembly arranged on the guide rail in a sliding mode, the lower portion of the top of the support is provided with a telescopic assembly, and the telescopic end of the telescopic assembly faces downwards and is connected with a spraying assembly. According to the scheme, two processes of shaking off a large filter cake by shaking and flushing residual impurities in filter holes by spraying pressurized water are combined, so that the filter pressing plate is quickly and easily cleaned, and the effect of high cleanliness is achieved.

The invention belongs to the technical field of reaction crystallization type solid-liquid separation, and particularly relates to filtering equipment with a reaction aging crystallization function. The device comprises a reaction kettle and a centrifugal filter disc which is located in the reaction kettle and can rotate and ascend and descend, and a reserved channel for materials to ascend and filter cakes to descend is formed between the disc edge of the centrifugal filter disc and the inner wall of the reaction kettle; the upper disc surface of the centrifugal filter disc is provided with a filter surface, a kettle cavity of the reaction kettle is communicated with a liquid accumulation cavity positioned in the centrifugal filter disc through the filter surface, the liquid accumulation cavity is communicated with a mother liquor outlet through a transition channel, and a slag outlet for discharging filter cakes is formed in the bottom of the reaction kettle. Through vertical reciprocating motion of the filter disc and multi-dimensional motion of rotation, rapid filtering and centrifugal discharging functions of materials needing reaction, aging and crystallization operation are achieved, smoothness of a filtering medium channel can be effectively guaranteed, and the effects of being simple in structure and compact in structure are achieved.

The invention discloses a novel electrolytic tank pipeline filter and a self-cleaning system. The novel electrolytic tank pipeline filter comprises a multi-stage filtering part, the self-cleaning system and an intelligent control system, the multi-stage filtering part comprises multi-stage filter elements arranged in the material pipeline, and the multi-stage filter elements are arranged from large to small according to the filtering particle size to form a filtering gradient; the self-cleaning system acts on the multi-stage filter element part at the same time or in a time-sharing manner on the basis of a fluid reverse recoil principle; the self-cleaning system is combined with pulsating flushing control, so that the filter element is separated from a filter cake at low loss; the multi-stage gradient filtration is adopted, impurities are efficiently and accurately intercepted, the filter elements with the particle sizes from large to small are arranged in a gradient mode, the first-stage titanium alloy filter element intercepts large particles, the second-stage polytetrafluoroethylene membrane filters tiny impurities, the efficiency is improved through graded interception, the loss of the filter elements is reduced, and the material purity and the hydrogen production quality are guaranteed. The multi-element self-cleaning technology is adopted, low-loss deep cleaning is achieved, and the self-cleaning system integrates multiple technologies such as fluid reverse backflushing, pulsating flushing, ultrasonic vibration and a pulsed electric field.

The invention discloses a method for controlling ion concentration and volume balance in an electrolyte by using nickel hydroxide. The method comprises the following steps: preparing a reaction base solution containing a first complexing agent and a first alkali; the first anolyte, a second complexing agent solution and a second alkali solution are simultaneously added to the bottom of the reaction base solution for stirring reaction, solid-liquid separation is performed after nickel hydroxide reaches the target particle size, and filtrate and a filter cake are obtained; washing the filter cake, and slurrying the filter cake by using a second anolyte to obtain a nickel hydroxide slurrying material; and adjusting the sodium ion concentration, pH and nickel ion concentration of the third anolyte by adopting a sodium hydroxide solution, a nickel hydroxide slurrying material and a nickel sulfate solution to obtain the catholyte. According to the invention, a feeding mode of feeding at the bottom is adopted, and a complexing agent is matched, so that crystals can stably grow and are convenient to filter; in the preparation process, aging and too high pH conditions are not needed, operation is simpler, labor intensity is small, the reaction rate is higher, and continuous treatment of the anolyte can be achieved.

The invention relates to the technical field of desulfurization slurry treatment, and discloses a vacuum dehydration device and a dehydration treatment system and method for desulfurization gypsum. The device comprises a belt conveyor, filter cloth is arranged on the belt conveyor, a filter assisting component is arranged above the filter cloth, and the filter assisting component can extend into a filter cake layer on the filter cloth and damage a surface air blocking layer on the top of the filter cake layer. According to the technical scheme provided by the invention, the surface air barrier layer at the top of the filter cake layer is destroyed by the filter aid part, and the air pressure difference formed on the two sides of the filter cake layer due to suction filtration is recovered, so that free moisture in gypsum slurry is separated from the gypsum slurry under the dual effects of pushing force generated by the air pressure difference and self gravity; the desulfurized gypsum with relatively low water content is obtained.

A lithium manganese iron phosphate substrate, cathode material, and their preparation method, as well as a lithium battery, belonging to the field of lithium-ion battery technology. The preparation of the lithium manganese iron phosphate substrate comprises the following steps: dissolving soluble ferrous salt, soluble manganese salt, phosphoric acid, and lithium hydroxide in deionized water to react, obtaining Material A; filtering Material A, taking the filter cake and drying it to obtain Material B; Heat treating Material B in an inert gas atmosphere to obtain the lithium manganese iron phosphate substrate. By coating the surface of the carbon-free nano lithium manganese iron phosphate substrate with metal oxides or metal salts and carbon, the coating layer formed on the surface of the composite lithium manganese iron phosphate material effectively prevents the reaction between the lithium battery and the electrolyte.

The invention discloses a method for reducing the content of aged starch and soluble miscellaneous sugar in alpha-cyclodextrin, and belongs to the technical field of alpha-cyclodextrin synthesis, the method comprises the following steps: liquefaction, conversion, primary filtration, inclusion, secondary filtration, complexing agent removal and post-treatment; the conversion comprises the following steps: adding alpha-CGTase and isoamylase into the starch liquefied liquid at 38-42 DEG C, adjusting the pH value to 5.30-5.70, and carrying out conversion to obtain a conversion liquid; the primary filtration comprises the following steps: carrying out enzyme deactivation treatment on the conversion liquid, filtering, washing a filter cake with water, and combining the washing liquid with the filtrate to obtain primary filtrate; and the secondary filtration comprises the following steps: filtering the material liquid containing the complex, taking a filter cake, and washing the filter cake with water to obtain the inclusion compound. The preparation method of the alpha-cyclodextrin is improved, so that the alpha-cyclodextrin with high yield and high stability is obtained, and the industrial controllability is realized.

The invention provides a method for preparing a catalyst and the catalyst prepared by the method. The method comprises the following steps: immersing alkoxy magnesium particles in molten paraffin, raising the temperature to 70-120 DEG C, and fully stirring to enable pores of the particles to be filled with the paraffin; filtering the mixture of the paraffin and the particles, cooling a filter cake to 0-40 DEG C, and removing the paraffin on the surfaces of the particles; flattening the surfaces of the particles by using a chlorinated silane compound to generate a product mixture; filtering and washing the product mixture to obtain flattened particles; removing paraffin in pores of the flattened particles to obtain porous flattened particles; and adding the porous flattened particles into a titanium compound at a temperature of-20 to 110 DEG C, and reacting to obtain the catalyst. By applying the technical scheme provided by the invention, the problems that the particle size of the catalyst is difficult to control and the catalyst is easy to break in the prior art can be solved, and the prepared small-particle-size catalyst has excellent sphericity and can retain the pore structure of original particles.

The invention discloses a method for preparing MHP by cyclic utilization of manganese precipitation post-solution, which comprises the following steps: mixing sodium hydroxide, magnesium oxide and manganese precipitation post-solution to obtain compound alkali slurry; mixing the laterite-nickel ore liquid subjected to iron and aluminum removal with the compound alkali slurry, and carrying out precipitation reaction to obtain MHP slurry; carrying out thickening treatment on the MHP slurry to obtain a dense underflow; filtering the dense underflow to obtain an MHP filter cake and filtrate; directly carrying out manganese precipitation treatment on the filtrate to obtain manganese slag and manganese-precipitated liquid; and reusing the manganese-deposited liquid in the preparation of the compound alkali slurry. According to the invention, a sodium hydroxide and magnesium oxide compounded system is utilized, so that the MHP precipitation process can be simplified to one step. And meanwhile, part of the manganese-deposited liquid is recycled to the alkali preparation process, so that the wastewater treatment cost is reduced, and the magnesium content in the MHP can be reduced by controlling the circulation amount of the manganese-deposited liquid, and the cost of preparing crystals through subsequent fine extraction of the MHP is reduced.