352results about "Crystallization regulation/control" patented technology

The invention relates to the technical field of parameter adjustment, and discloses a low-temperature evaporative crystallization machine parameter adjustment method, device and equipment and a storage medium, and the method comprises the steps: collecting M groups of temperature sensor data and N groups of pressure sensor data of a low-temperature evaporative crystallization machine, calculating a first uncertainty representation of temperature parameter measurement and a second uncertainty representation of pressure parameter measurement; performing data fusion to obtain an optimal estimated value of a temperature state and an optimal estimated value of a pressure state; parallel prediction is carried out through the thermodynamic equilibrium model, the crystallization kinetic model and the system response model, and a crystallization process prediction result is obtained; according to the technical scheme of the invention, the interference of the feeding fluctuation, the environmental change and the like can be effectively handled, and the real-time updating of the control strategy and the accurate adjustment of the temperature and pressure parameters can be realized.

The invention relates to the technical field of grease production control, in particular to a grease product production control method and system based on intelligent digitization. The method comprises the following steps: monitoring temperature, viscosity and turbidity data in a grease crystallization process in real time, and generating grease crystallization state snapshot data; performing crystallization state prediction according to the grease crystallization state snapshot data, and performing reaction kettle cooling rate adjustment to obtain a target control cooling rate; performing real-time stirring rotating speed adjustment fuzzy reasoning on the grease crystallization state snapshot data to generate a corrected grease stirring speed; and performing control instruction conversion on the target control cooling rate and the corrected grease stirring speed, executing a production control instruction, and generating a grease crystallization process control report. By accurately controlling the cooling rate and the stirring speed, intelligent control over the grease crystallization process is achieved, and the quality and stability of grease products are remarkably improved.

The invention relates to the technical field of automatic control, in particular to a monitoring method and system for synthesizing ceramide based on alpha-hydroxy fatty acid, and the monitoring system for synthesizing ceramide based on alpha-hydroxy fatty acid comprises a raw material feeding module, a reaction control module, a quenching-crystallization joint control module and a data integration module; carrying out dynamic weighing monitoring on the raw materials based on the received synthesis instruction, and starting a reaction kettle according to weighing data; performing multi-dimensional data acquisition in real time according to the set reaction data, and performing dynamic feeding control according to the set reaction data; when the TLC detection substrate reaction is completed, the cooling process and the crystallization process are regulated and controlled in real time according to the reaction data until the end point judgment standard is met; according to a received synthesis completion instruction, product quality data is obtained, a monitoring data packet is generated, the synthesis instruction is marked and then stored, process control is accurately monitored and controlled, and the purity and crystal form of the product are ensured.

The invention provides a system and a method for producing high-purity electronic-grade carbonic ester, and the system comprises a heterogeneous reaction section, a separation section and a crystallization section along the material flow direction, the heterogeneous reaction section is used for carrying out heterogeneous reaction on ethylene oxide and carbon dioxide to prepare carbonic ester; the separation section is used for separating materials from the heterogeneous reaction section and comprises a flash evaporation unit and a rectification unit in the material flow direction, and the flash evaporation unit comprises at least one flash evaporation tank; the rectification unit comprises at least one rectification tower, and the side-draw of the rectification unit is communicated with the feed port of the crystallization section; and the crystallization section is used for crystallizing and purifying the material mainly containing carbonic ester from the separation section. According to the method, high-purity ethylene carbonate used as a power battery can be obtained from the crystallization section, and crystallization mother liquor can be selectively returned to the separation section to be concentrated. The method can effectively improve product purity, reduce product chromaticity and reduce energy consumption, and can be applied to industrial production of carbonic ester.

The invention provides an intelligent dynamic flow rate regulation and double-effect crystallization evaporation device which comprises a feeding system, a double-effect evaporation system, a crystallization system, a circulating pump and a flow rate regulation system, the feeding system is connected to the double-effect evaporation system through a pipeline, the double-effect evaporation system is connected to the crystallization system through the circulating pump, and the flow rate regulation system is connected to the crystallization system through a pipeline. The flow rate adjusting system is connected with the circulating pump and the double-effect evaporation system, and the device realizes intelligent dynamic flow rate adjustment through the circulating closed-loop control system, so that the evaporation efficiency and the crystallization quality are optimized. The circulating closed-loop control system comprises a data acquisition unit, a data processing unit, a flow velocity adjusting system, a feedback optimization unit and an abnormity early warning unit, a flow velocity adjusting strategy is optimized based on real-time data, historical data and machine learning, scaling is reduced through disturbance flow velocity control, and the system stability is improved. The evaporation and crystallization efficiency is improved, the energy consumption is reduced, different working condition requirements are met, and the method is suitable for the field of industrial evaporation and crystallization.

The invention provides a cooling rate optimization control method and system for continuous cooling crystallization, and the method comprises the steps: collecting crystal slurry concentration data and temperature data of each stage of crystallization tank in real time; the crystal slurry concentration data, the temperature data and the feeding flow data are input into a deep learning model, and a prediction result is obtained; based on the prediction result and crystal mush concentration data, dynamically adjusting the cooling rate of each stage of crystallizing tank and the addition amount of a co-crystallizing solvent; and feeding back an outlet crystal mush concentration signal of the last-stage crystallizing tank to the solid-liquid separation unit, and adjusting the running rotating speed of the solid-liquid separation unit in a linkage manner. According to the cooling rate optimization control method and system for continuous cooling crystallization, prospective correction of the cooling rate is carried out by using the predicted supersaturation degree, and adjustment of the additive amount of the auxiliary crystallization solvent is carried out by using the predicted crystal particle size distribution; and finally, an outlet concentration signal of the last-stage crystallizing tank is fed back to the solid-liquid separation unit in real time to adjust the separation rotating speed in a linkage manner, so that the crystal particle size deviation is reduced, and the triazole crystallization recovery rate is improved.

The invention provides an ultrasonic-assisted gamma-aminobutyric acid crystallization particle size regulation and control method, which comprises the following steps: removing impurities and decolorizing gamma-aminobutyric acid-containing feed liquid, heating, stirring and concentrating to a nearly saturated state, then carrying out ultrasonic-assisted crystallization, cooling, aging and suction filtration to obtain coarse crystals, and finally washing and drying to obtain target crystals. According to the method, a synergistic process of raw material liquid pretreatment, evaporation concentration-ultrasonic-cooling coupling crystallization, aging and post-treatment is adopted, an ultrasonic cavitation effect is utilized to reduce a nucleation barrier, and a supersaturation degree precise control and gradient cooling strategy is combined, so that grain size refinement, obvious narrowing of distribution and effective inhibition of agglomeration of crystals are realized; the median particle size of the crystal can be controlled to be smaller than or equal to 200 microns, the particle size distribution span is smaller than or equal to 1.5, the agglomeration phenomenon is remarkably inhibited, the crystal form is kept stable, the crystal habit is complete and smooth, the crystal product quality and the process efficiency are remarkably improved, and the method has important industrial application value.

The invention belongs to the technical field of energy storage batteries, and particularly relates to a desalting, dehumidifying and cooling integrated thermal management device and method for a marine environment energy storage battery. The device is composed of an energy storage battery module, an air inlet dehumidification and desalination module, an air return reprocessing module, a salt crystallization and separation module, a cold source heat exchanger and a heat source heat exchanger. Wherein the inlet air dehumidification and desalination module cools inlet air by utilizing a first solvent and inlet air cross flow heat exchange mode, meanwhile, the first solvent dissolves salt mist ions in inlet sea wind, and the purposes of reducing the dew point temperature and dehumidifying the inlet sea wind are further achieved; in order to ensure water-salt concentration balance of the first solution, a salt crystallization precipitation module and a return air retreatment module are adopted to jointly adjust the concentration of the first solution. A solution is provided for safe and reliable operation of the energy storage battery system under the ocean high-temperature, high-humidity and high-salt links.

A method of making colloidal kagome superlattices can include functionalizing a plurality of metal nanoparticles with a plurality of oligonucleotides to produce programmable atom equivalents; and cooling the programmable atom equivalents to induce crystallization of the programmable atom equivalents. The cooling process can include cooling the PAEs from a first temperature to a second temperature at a first cooling rate, cooling the PAEs from the second temperature to a third temperature at a second cooling rate, and cooling the PAEs from the third temperature to a fourth temperature at a third cooling rate. The kagome superlattices can have a rhombohedral unit cell formed by alternating chiral layers of PAEs organized in 2-dimensional distorted kagome layers. The colloidal superlattices can have anisotropic light emission, Purcell factors of at least 25 and birefringent properties.

The invention relates to a one-way valve and static crystallization equipment. The one-way valve comprises a valve body and a valve cover which are hinged, a second rack and a first rack which are meshed with each other are arranged on the valve body and the valve cover respectively, and when the one-way valve is opened, a gap is formed between the second rack and the first rack. The valve body and the valve cover which are hinged are arranged, the second rack and the first rack which are meshed with each other are arranged on the valve body and the valve cover correspondingly, when the one-way valve is opened, a gap is formed between the second rack and the first rack, and the valve body can be sealed through cooperation of the second rack and the first rack; under the impact action of airflow, the valve cover and the valve body are repeatedly opened and closed, at the moment, a small gap is formed between the first rack and the second rack, gas overflows from the gap, the gap between the racks assists the gas in further reducing bubbles formed by the gas, more small bubbles are formed, the number and dispersity of the bubbles are increased, the crystallization time is shortened, and the crystallization efficiency is improved; the energy consumption is reduced and the finished product purity is improved.

The invention relates to a liquid level control device of a vacuum crystallizer. Relates to the technical field of vacuum crystallization. The device comprises a flash tank arranged below a crystallization pot, the flash tank is provided with an overflow port, and the bottom end of a discharge pipe extends into the flash tank and is lower than the overflow port, so that feed liquid and liquid level in the flash tank automatically flow out of the overflow port when reaching the height of the overflow port. The overflow port is formed in the overflow groove, the bottom end of the discharge pipe extends to the position below the overflow port in the overflow groove, when the liquid level of feed liquid in the overflow groove reaches the height where the overflow port is located, the feed liquid automatically flows out of the overflow port, liquid level control over the feed liquid in the overflow groove is achieved, and therefore the liquid level of the feed liquid in the overflow groove is controlled. The liquid level control device is simple in structure, reliability of liquid level control in the vacuum crystallizer can be improved, and then the effect of liquid level control in the vacuum crystallizer is guaranteed.

The invention provides a production device and process for increasing the content of magnesium citrate crystals. The problems that in the prior art, the impurity co-crystallization rate is high, and crystal forms are difficult to control are solved. The device comprises a gradient temperature control multi-stage crystallization device and a crystal form directional regulation and self-adaptive separation system. The gradient temperature control multi-stage crystallization device is composed of a main crystallizer, a gradient temperature control system, an ultrasonic-assisted system and a liquid phase partition circulating system, and the crystallization environment is accurately controlled through the temperature gradients of five independent temperature zones. The crystal form directional regulation and self-adaptive separation system is composed of a seed crystal dynamic inoculation device, an electric field auxiliary directional crystallization system, a real-time crystal morphology analysis system and a self-adaptive separation system, and the crystal morphology and particle size distribution can be accurately controlled. According to the process disclosed by the invention, the main content of magnesium citrate is increased to 98.8 + / -0.3%, heavy metal impurities and organic impurities are respectively reduced by 70% and 75%, the crystal form consistency is increased to 96 + / -2%, the production period is shortened by 33%, and the process has remarkable economic benefits and social benefits.

The invention relates to the technical field of mixing equipment, and discloses a mixing preparation device and method for a plant growth regulator containing a silicon element. The mixing preparation device of the silicon-containing plant growth regulator comprises a stirring main kettle, an online monitoring unit, a solid-liquid separation unit and a control unit, the stirring main kettle is used for carrying out a liquid-phase chemical reaction and separating out a solid product in situ, and is provided with a stirring piece; and the on-line monitoring unit is used for acquiring a reaction process signal and a crystallization state signal in the main stirring kettle in real time. The online monitoring unit, the solid-liquid separation unit and the control unit are arranged and cooperatively used, dynamic optimization management of the reaction crystallization process is achieved, the solid-liquid separation unit moves out crystals in time and circularly supplements materials, the problem that the crystals are secondarily wrapped is solved, meanwhile, reaction balance is pushed to move rightwards, and the reaction efficiency is improved. The conversion rate and the yield are improved.

The invention provides a p-xylene crystallization tower. The p-xylene crystallization tower comprises a tower body, a cooling structure and a scraper structure, mixed xylene is contained in the tower body; the cooling structure comprises a sealing plate and liquid conveying pipes arranged at the upper end and the lower end of the sealing plate respectively, and the sealing plate surrounds the periphery of the tower body; the sealing plate is wavy; the sealing plate comprises a plurality of wave trough parts and a plurality of wave crest parts which are alternately arranged, the wave trough parts are tightly connected with the periphery of the tower body, and the sealing plate and the periphery of the tower body define a circulation channel extending in the vertical direction between any two adjacent wave trough parts; the liquid conveying pipes are arranged on the periphery of the tower body in a surrounding mode, and the two liquid conveying pipes communicate with the multiple circulation channels correspondingly. And the refrigerating medium is input into the circulation channel through the liquid conveying pipe. And the mixed xylene is cooled under the action of the refrigerating medium, and paraxylene is crystallized and separated out on the inner circumferential wall of the tower body. And the scraper structure scrapes crystals on the tower body. According to the p-xylene crystallization tower, a refrigerating medium is in close contact with the tower body, so that the dissipation of cold energy is effectively reduced, and the refrigerating effect is improved.

The invention provides a production device and process for recovering electronic-grade phosphoric acid from waste etching liquid. The device comprises a raw material storage tank, a multi-stage filtration system, a phosphoric acid evaporation kettle, a purification system, a mixed acid storage tank and a neutralization reaction and crystallization system. The waste etching liquid enters an evaporation kettle after being subjected to multi-stage filtration to remove suspended solid particles, and phosphoric acid is separated from volatile nitric acid and acetic acid; and condensing the volatile acid into mixed acid for storage, and removing metal ions from the semi-finished phosphoric acid through a purification system to obtain the electronic-grade phosphoric acid. The mixed acid reacts with alkali to generate a mixed solution of sodium acetate and nitric acid, sodium acetate crystals are separated out through evaporation and concentration, a solid product is obtained after separation, nitric acid is obtained by condensing gas, and suspended particles and metal impurities are subjected to incineration treatment. Through the steps of filtering, negative-pressure evaporation, neutralization and crystallization and the like, the process realizes efficient recovery of electronic-grade phosphoric acid and byproducts of sodium acetate and nitric acid, and has the characteristics of high resource recovery rate and low pollution emission.

The invention relates to the field of calcium gluconate evaporative crystallization equipment, in particular to a crystallizing tank for calcium gluconate crystallization production and a using method thereof.The crystallizing tank comprises an evaporative crystallization tank body, the evaporative crystallization tank body comprises a tank body, a stirring and uniform heating assembly is arranged on the inner edge of the tank body, and an adaptive adjusting assembly is installed on one side of the stirring and uniform heating assembly; a crystal transfer assembly is arranged at the middle part in the tank body; the stirring and uniform heating assembly is used for stirring the to-be-crystallized solution in the tank body to uniformly disperse heat; the adaptive adjusting assembly is used for adaptively adjusting the stirring and heat uniformizing assembly according to the evaporation progress; according to the crystal stirring device, the situation that the stirring work is easily affected in the later period that the crystals are continuously accumulated at the bottom in the tank body and become high can be avoided, and meanwhile the situation that the crystals are likely to collide with a stirring component along with flowing of a solution, and consequently the crystals are broken can be effectively reduced.

The invention relates to the technical field of insecticides, and discloses an indoxacarb finished product crystallization device and method.The indoxacarb finished product crystallization device comprises a supporting bracket, a stirring tank is arranged at the top of the supporting bracket, an opening plate is arranged on one side of the stirring tank, a mounting frame is arranged at the top of the stirring tank, a driving source is arranged on the mounting frame, and a rotating shaft is arranged at the output end of the driving source; a fixing frame is arranged at the bottom of the inner wall of the stirring tank, and a homogenizing assembly is arranged on the fixing frame; the fixing frame is further provided with a vibration assembly. The homogenizing assembly is used for uniformly mixing the indoxacarb finished product solution in the stirring tank; the vibration assembly is used for reducing the phenomenon of local supersaturation of liquid in the stirring tank through vibration. Compared with the prior art, crystal agglomeration can be reduced, the particle distribution uniformity can be improved, the wall surface scaling risk can be reduced, the cleaning and maintenance frequency can be reduced, and the production efficiency and the product quality can be improved.

According to the low-energy-consumption evaporating crystallizer, a single driving motor is adopted, a rotating shaft rod is used for simultaneously driving a scale scraping assembly arranged in an evaporating cylinder to conduct dynamic scale scraping and solution stirring, one end of the rotating shaft rod passes through a first transmission mechanism and a linkage shaft, and the other end of the rotating shaft rod is driven by a second transmission mechanism. A spiral separation assembly in the gas-liquid separation tank is driven by the direction conversion mechanism to rotate at a high speed so as to strengthen gas-liquid separation; and the other end of the discharging pipe drives a discharging assembly in the discharging pipe to rotate through a second transmission mechanism, so that discharging blockage prevention and negative-pressure deslagging are realized. Through a single power source, cooperative linkage of five functions of scale scraping, stirring, separation, blocking prevention and slag discharging is achieved, the structure is compact, the problems that traditional equipment is serious in scaling, poor in gas-liquid separation effect and prone to blockage during discharging are effectively solved, and meanwhile energy consumption of the equipment is remarkably reduced.

The invention discloses a diiodosilane purification method and a purification processing system, relating to the technical field of diiodosilane. A driving component is provided on a mounting shell, an inner liner is clamped on an output end of the driving component, the driving component is slidably connected to a sliding groove provided on the mounting shell, the inner liner is located in a sliding cavity in the mounting shell, the sliding cavity is communicated with the sliding groove, a limiting component is installed on the mounting shell, a notch is provided on the mounting shell, the limiting component is tilted toward the notch, and the crystals can be quickly taken out by taking out the inner liner, thereby enhancing work efficiency, facilitating the rapid removal of the crystals, and enabling the next crystallization to be carried out quickly. Moreover, by arranging a filter screen and a railing on the inner liner, the residual liquid in the inner liner can be quickly discharged, thereby preventing the residual liquid from affecting the purity of the diiodosilane.

The invention relates to the technical field of ammonium dihydrogen phosphate preparation, and discloses a high-purity ammonium dihydrogen phosphate crystallization device and a method thereof.The high-purity ammonium dihydrogen phosphate crystallization device comprises a first-stage crystallization system, a first-stage centrifugal separation system, a second-stage crystallization system and a second-stage centrifugal separation system which are connected in series. The primary crystallization system comprises a crystal elimination heater, a crystal elimination mixer, a bag filter and a DTB flash cooling crystallizer which are connected in sequence, and is used for primarily purifying a concentrated solution; the primary centrifugal separation system is used for separating primary crystals; the second-stage crystallization system comprises a crystal dissolving tank, an OSLO cooling crystallizer and the like, and deep crystallization is carried out after the first-stage crystal is dissolved; the secondary centrifugal separation system is used for separating secondary crystals; through two-stage crystallization coupling, mother liquor graded circulation, a unique gradient washing process and active impurity control, efficient and continuous production of battery-grade ammonium dihydrogen phosphate with wet-process phosphoric acid as a raw material is realized, the product purity is high, the process flow is simplified, the cost is low, and the system operation is stable.

The invention discloses a diiodosilane purification method and a purification processing system, and relates to the technical field of diiodosilanes. A driving assembly is arranged on a mounting shell, an inner container piece is clamped to the output end of the driving assembly, the driving assembly is in sliding connection with a sliding groove formed in the mounting shell, the inner container piece is located in a sliding cavity in the mounting shell, and the inner container piece is connected with the driving assembly in a sliding mode; the sliding cavity is communicated with the sliding groove, a limiting assembly is mounted on the mounting shell, a notch is formed in the mounting shell, the limiting assembly inclines towards the notch, crystals can be rapidly taken out by taking out the inner container piece, the working efficiency is improved, the crystals can be rapidly taken out conveniently, the next time of crystallization can be rapidly carried out, and the crystallization efficiency is improved. And a filter screen and a handrail are arranged on the inner container piece, so that residual liquid in the inner container piece can quickly flow out, and the residual liquid is prevented from influencing the purity of diiodosilane.

The invention relates to the technical field of propiconazole purification, in particular to a propiconazole purification device which comprises a purification tank, and the top end of the purification tank is fixedly communicated with a fixed cover; the detection mechanism comprises a semicircular lamp panel for emitting light, a photoresistor plate for detecting the light emitted by the semicircular lamp panel is arranged in the purification tank, and the detection mechanism is used for detecting the concentration and crystallization degree of a solution needing to be purified. A semicircular lamp panel in the detection mechanism emits light, the absorption and scattering of the light are influenced by the concentration of a solution, the intensity of light irradiated on the photosensitive resistor plate is changed, and then the resistance value of the photosensitive resistor plate is changed. When the solution concentration is high, the light intensity and the resistance value are large, the current passing through the electromagnet is large, the electromagnet is strong in magnetism, the permanent magnet on the sliding plate is repelled to slide upwards, the L-shaped conducting strip slides upwards on the resistor strip, the resistance of the sliding rheostat is reduced, the current passing through the self-adaptive adjusting loop is increased, and the stirring speed is increased.

The invention relates to the technical field of water treatment, in particular to a sludge phosphorus release and phosphorus crystal recovery device which comprises a phosphorus release mechanism and a phosphorus crystal recovery mechanism, and the phosphorus release mechanism comprises a sludge concentration unit, a sludge breaking assembly and a sludge dewatering unit; the sludge disintegration assembly comprises a sludge disintegration unit and a pH value adjusting unit, the phosphorus crystal recovery mechanism comprises an outer shell, a middle shell, an inner shell, a plug flow stirring assembly, a folded plate vortex assembly, a modular vortex assembly, an inclined plate assembly and a micro-nano aeration disc, the outer shell, the middle shell and the inner shell are combined to form a unique circulation channel, and the outer shell, the middle shell and the inner shell are combined with the micro-nano aeration disc; according to the method, small-particle crystals are used as seed crystals to enter a circulating channel, so that ready-made nucleation sites are provided for a solution, the critical supersaturation degree required for forming new crystal nucleuses is reduced, the probability of spontaneous nucleation is reduced, the generation of irregular dendritic or needle-shaped crystals is inhibited, and the formation of more compact and uniform prismatic or sheet-shaped large-particle crystals is promoted; and efficient phosphorus release and phosphorus crystal recovery are realized.

The application provides an amino acid composite reagent system and a method for treating electronic waste to prepare high-purity glycine copper, and belongs to the technical field of metal hydrometallurgy and resource recycling. The application builds an ammonia catalytic reduction mechanism by designing an amino acid composite reagent system, greatly improves the leaching rate, simultaneously inhibits the dual effects of copper hydroxide precipitation and glycine chelation, and realizes efficient solution of copper ions; through narrow window regulation technology of pH at 9.5±0.2, the stability of ammonia, the activity of glycine anion are maintained, and the selective leaching rate of copper is ensured; a directional crystallization process of leaching solution is constructed, the "self-assembly directional crystallization" process of glycine copper chelate is used, based on the saturation concentration of glycine copper in the leaching solution and the stable chelate structure, through three-stage crystallization precise regulation, the preparation of high-purity crystal is realized. The process realizes the closed-loop crystallization system of "zero addition of crystal seeds and zero wastewater discharge" of the copper-containing complex leaching solution of electronic waste.

This application relates to the field of functional crystalline material preparation and microfluidic application technology, specifically disclosing a method and product for preparing formate crystals using core-shell microcapsules, including the following steps: (1) dissolving a solid alkaline raw material in a formic acid solution to prepare reaction solution a; (2) separately conveying polymer solution A and polymer solution B with phase separation characteristics, and reaction solution a, so that they are mixed at the intersection of microchannels to prepare dispersed phase b, which is then introduced into the assembly zone for phase separation assembly to form core-shell microcapsules; (3) the core-shell microcapsules are crystallized in a continuous temperature-changing crystallization zone to form formate solid; (4) the formate solid is collected, washed and dried sequentially to obtain the target product; (5) the oil layer is continuously extracted and returned to the assembly zone for recycling. The formate crystals prepared in this application not only have a large particle size, but also exhibit good size uniformity and morphological repeatability, and have the advantages of high throughput, green environmental protection, and simple operation.

The invention discloses a use method of 2, 4-dihydroxybenzoic acid dissolving and recrystallizing equipment, the 2, 4-dihydroxybenzoic acid dissolving and recrystallizing equipment comprises a closed dissolving kettle, a crystallization kettle and a mother liquor storage tank, the closed dissolving kettle, a first separator, a first filtrate storage tank and the crystallization kettle are connected in sequence, and the mother liquor storage tank is connected with a second separator. A discharge port of the crystallization kettle is connected with a feed port of a second separator, a filtrate discharge port of the second separator is connected with a liquid inlet of a second filtrate storage tank, and a liquid outlet of the second filtrate storage tank is communicated with a liquid inlet of the mother liquid storage tank through a third pipeline; the second pipeline between the first separation column and the second pump body is communicated with a liquid outlet of the mother liquid storage tank through a fourth pipeline; the second pipeline between the second pump body and the fourth pipeline is communicated with one end of a backflow pipeline, and the other end of the backflow pipeline is communicated with the first pipeline. The 2, 4-dihydroxy benzoic acid dissolving and recrystallizing equipment disclosed by the invention can be used for preparing 2, 4-dihydroxy benzoic acid with the purity of 99.68%, and the content of metal ions is reduced to 0.15 ppm.

The present invention relates to the field of crystallization technology, and in particular to a laboratory crystallization device. It comprises a rotating drum, a barrel, a heating device and a rotating device; a seed crystal is arranged on the surface of the rotating drum, a feed liquid is contained inside the barrel, the rotating drum is placed above the feed liquid, so that the seed crystal layer on the surface of the rotating drum is immersed in the preset depth of the feed liquid surface, the feed liquid comprises an excess of solid material to be recrystallized, and the feed liquid dissolves the material to be recrystallized, the heating device is installed outside the barrel, and is used to heat the feed liquid to keep its temperature at a preset temperature, water with a temperature of a preset water temperature flows in the rotating drum, so that the temperature of the crystal layer on the rotating drum is the preset water temperature, and the rotating device is used to rotate the barrel. The present invention provides a laboratory crystallization device, which can obtain large-sized crystals.

The invention relates to a continuous crystallization system and method of lithium hexafluorophosphate, and belongs to the technical field of lithium ion battery electrolyte production. Aiming at the characteristics and requirements of a lithium hexafluorophosphate cooling crystallization process, the invention provides a continuous crystallization system of lithium hexafluorophosphate, which separates cooling nucleation from cooling crystallization. An ultrasonic generating device is introduced into the cooling nucleation module, lithium hexafluorophosphate is stimulated and induced by ultrasonic waves to nucleate, limitation of a metastable region is reduced, the nucleation rate is increased, crystal nuclei are controlled to be within a small particle size distribution range, meanwhile, introduction of impurities in the nucleation process is reduced, and the product purity is guaranteed. And the lithium hexafluorophosphate solution to be crystallized can continuously and uninterruptedly enter the cooling nucleation module, the cooling crystallization module and the separation circulation module in sequence, so that the continuous crystallization of the lithium hexafluorophosphate is realized, the crystallization time is greatly shortened, and the crystallization efficiency is improved.

Method for producing electronic grade nickel sulfate from nickel powder, crystallization apparatus, and control thereof The present invention provides a method for producing nickel sulfate, and nickel sulfate produced thereby. The process includes acid leaching, copper removal, acid adjustment, concentration, cooling crystallization, drying and sieving, and secondary leaching. Oxidation In the calcination furnace, the temperature is 400 to 700°C, and 1 kg of compressed air is used for each kilogram of nickel powder. ~5m 3 The reaction time is 1.0 to 2.5 hours, and the temperature during acid immersion is controlled to 45 to 70°C. Then, add dilute sulfuric acid to control the pH to 0.5-1.5 and react for 1-3 hours. The copper removal is to replace the copper with nickel powder, and the acid conditioning is to use nickel hydroxide or The pH is adjusted to 2.5-4.5 using nickel carbonate, and the filtrate is concentrated by The cooling crystallization method is to obtain nickel sulfate crystals and return the mother liquor to the concentrate. Drying and sieving is to add the undersieved material to the crystallizer as seed crystals, and secondary leaching is to Dilute sulfuric acid is added to the leaching slag, and it is reacted with nickel sulfate or hydrogen peroxide until nickel is less than 0.1%. If the first stage is full, the second leaching is continued. The crystallizer is a crystallizer that is connected in series with a second-stage crystallizer and a third-stage crystallizer. A crystallization frame, an oscillator provided under the crystallization frame, and an oscillator provided at the exit end of the crystallization frame. The crystallization frame is a rectangular parallelepiped. The bottom of the ribs are evenly spaced, with a cross section of a circular arc. The distance between two adjacent ribs is S is 1 / 25 to 1 / 15 of the width of the crystallization frame, and either the width b or the height h of the rib The width of the crystallization frame is 1 / 100 to 1 / 150 of the width of the crystallization frame. It does not add any new impurity ions, and does not add any oxidizing agent. The nickel sulfate crystal particles produced are uniform and are free of the static generation. This avoids caking of very large particles, irregularly shaped particles and crystals.

The present disclosure provides a preparation system and a preparation method for xylitol crystals. In the preparation system, outlets of a first centrifuge are connected with an inlet of a hot air drying tank and an inlet of a primary mother liquor storage tank through pipelines, respectively. Outlets of a second centrifuge are connected with an inlet of a second fluidized bed dryer and an inlet of a secondary mother liquor storage tank through pipelines, respectively. An outlet of a dicrystalline sugar dissolution tank is connected with an inlet of a blending tank through a pipeline. An outlet of a tricrystalline sugar dissolution tank is connected with the inlet of the primary mother liquor storage tank. The blending tank is provided with an inlet for a raw material of xylitol hydrogenation solution. An output of an outlet of a first fluidized bed dryer is prepared xylitol crystals.