925 results about "Fine powder" patented technology

The invention discloses a method for preparing spherical metal fine powder by using coarse / waste powder through ultrasonic atomization, which comprises the following steps of: (1) collecting coarse / waste powder raw materials for ultrasonic atomization powder preparation, (2) conveying the coarse / waste powder to an electric arc melting area through argon gas flow, and carrying out melting and ultrasonic atomization powder preparation processing; (3) in the powder preparation process, the powder is continuously collected by using argon circulating airflow, so that the continuity of the powder preparation process is ensured; and (4) finally screening the prepared powder in particle size ranges to obtain high-quality spherical fine powder in different particle size ranges. According to the method, the recycling and reusing problems of 3D printing splashing waste powder and coarse powder in the traditional gas atomization powder manufacturing process are solved, and the powder pollution risk is remarkably reduced; according to the ultrasonic atomization re-powdering technology, the high-quality spherical metal fine powder needed by additive manufacturing can be efficiently prepared, powder waste discharge and environmental burden are reduced, the obtained powder can be directly used as a high-quality raw material for additive manufacturing, and green and sustainable development of the metal additive manufacturing industry is promoted.

The invention provides a porous ceramsite adsorption material prepared from straw biochar and rare earth tailings as well as a preparation method and application of the porous ceramsite adsorption material, and belongs to the technical field of environmental functional adsorption materials. The preparation method of the porous ceramsite adsorption material using the straw biochar and the rare earth tailings comprises the following steps: sequentially performing acid pickling and drying on the straw biochar to obtain acidified biomass charcoal; the rare earth tailings are subjected to ball milling, and tailings fine powder is obtained; mixing the acidified biomass charcoal, the tailing fine powder, the attapulgite and the wood chips to obtain a mixture; adding a binding agent and water into the mixture, and sequentially performing kneading and extrusion molding to obtain a ceramsite precursor; and calcining the ceramsite precursor in a protective atmosphere to obtain the porous ceramsite adsorption material. The technical problems that a traditional adsorption material is low in adsorption capacity, poor in strength and difficult to recycle are solved through ternary compounding of the acidified biomass charcoal, the rare earth tailings and the attapulgite and in combination with wood chip pore-forming, segmented calcination and acid pickling pretreatment.

The invention provides a hot-state repairing material and a preparation method thereof, and belongs to the technical field of refractory materials. The hot-state repairing material provided by the invention is prepared from the following raw materials in percentage by mass: 87 to 98 percent of waste bricks, 0.5 to 4.5 percent of magnesium mineral micro powder, 0.5 to 5.0 percent of slag powder, 0.5 to 2.0 percent of dispersing agent, 0.2 to 1.5 percent of organic fiber and 0.1 to 0.5 percent of binding agent. According to the invention, waste bricks are used as aggregates, contain tiny pores, provide channels for reaction gas for heating the hot-state repairing material, and can be rapidly sintered with a furnace lining; the slag powder can be matched with the binder to improve the thermal adhesion rate of the thermal repairing material; the magnesium mineral micro powder can improve the reaction activity, and the dispersing agent assists the combination effect of the slag powder, so that the repairing material can be sintered through rapid reaction, and the compression strength and the erosion resistance are improved; and the organic fibers can form good filling among particles and fine powder, so that the compression strength and the erosion resistance are improved.

The invention relates to the technical field of building construction, in particular to a cement material stirring device for building decoration engineering construction, a screening mechanism in the cement material stirring device drives an inclined box and an internal inclined screen to continuously move up and down in a reciprocating manner through a transmission assembly, and dynamic screening of input cement is achieved; qualified powder rapidly penetrates through the screen and enters a subsequent process through the vertical pipe, intercepted agglomerates automatically roll down to a lower outlet under the action of vibration and inclination, the agglomerated cement materials are screened, meanwhile, the smashing mechanism ingeniously obtains power from a driving motor through a rotating shaft, and the smashing efficiency is improved. Crushing cutters distributed on a first rotating rod and a second rotating rod in a staggered mode in the box body are driven by a bevel gear and a gear set to rotate oppositely at a high speed, cakes falling from a lower outlet are thoroughly cut and scattered, the cakes are reduced into fine powder and then collected into a stirring barrel, and the efficiency and quality of raw material preparation before stirring are greatly improved; and the problem of non-uniform slurry caused by cement caking and core hardening is fundamentally avoided.

This invention provides an environmentally friendly expandable polystyrene bead and its preparation process, belonging to the field of foaming material technology. The preparation process includes the following steps: S1, injecting 65.28g of deionized water into a reaction vessel, stirring, adding 0.13g of dispersant and 0.16g of composite stabilizer, dispersing for 20min, then adding 31.95g of styrene monomer and 0.3g of composite initiator, followed by the addition of pentane and SiO2 micelle composite to obtain a base solution; wherein the mass ratio of pentane to SiO2 micelle composite is 1:(0.2-0.3); the mass of pentane is 3.1%-3.2% of the mass of the base solution; S2, subjecting the base solution to stepwise heating at 86℃-140℃ with stirring, then stopping heating, continuing stirring, and allowing it to cool naturally to 40℃, then stopping stirring, with a total reaction time of 8.5-9.5h to obtain the reaction product; S3, discharging the material, washing the reaction product with warm water, filtering, and obtaining the environmentally friendly expandable polystyrene beads. This invention improves the average particle size of expandable polystyrene beads while reducing fine powder.

The invention discloses a method for improving the utilization rate of nickel-based powder superalloy, which comprises the following steps: preparing alloy powder from mother alloy through a powder preparation process, screening the alloy powder to obtain powder with the particle size of less than 150 microns, and dividing the powder into fine powder and coarse powder; wherein the fine powder refers to powder with the particle size smaller than 53 micrometers, the coarse powder refers to powder not smaller than 53 micrometers, and the alloy is prepared from the fine powder and the coarse powder through a forming process. The invention further provides application of the alloy prepared through the method to hot end components of aerospace, ships and energy power systems. The applicant provides the method for improving the utilization rate of the nickel-based powder high-temperature alloy and the related alloy, and verifies that coarse powder with the particle size of 53-150 microns and fine powder with the particle size of 18-53 microns are on the same level in structure form and comprehensive mechanical property, and the powder utilization rate is greatly improved.

To provide a method for producing PHA, capable of suppressing generation of fine powder without using a binder.SOLUTION: A method for producing a PHA fused body, comprising a step (a) of dehydrating an aqueous PHA suspension to obtain a PHA wet powder having a water content of 5 to 37%, a step (b) of heating the obtained PHA wet powder at 75 °C to 95 °C to obtain a PHA powder having a water content of 0.5% or less, and a step (c) of heating the obtained PHA powder at 100 °C to 150 °C to obtain a PHA fused body.SELECTED DRAWING: None

The invention provides a refractory ceramic-based material for a smelting furnace lining and a preparation method of the refractory ceramic-based material, and belongs to the technical field of ceramic refractory materials. The material comprises coated modified fused magnesite main aggregate, ceramic sand main aggregate, surface coated magnesium oxide fine powder, gamma-phase aluminum oxide micro powder, an aluminum dihydrogen phosphate solution, alkaline silica sol, a pre-reaction spinel precursor and zirconium boride micro powder. The coated modified fused magnesite main aggregate is prepared by mixing and sintering fused magnesite, silicon carbide composite powder, chromium sesquioxide powder and phenolic resin powder. And mixing the silicon carbide powder and the magnesium oxide powder, and depositing a silicon nitride layer on the particle surface to prepare the silicon carbide composite powder. The surface-coated magnesium oxide fine powder is formed by coating the surfaces of magnesium oxide fine powder particles with aluminum oxide. The pre-reaction spinel precursor is prepared by the following steps: preparing a mixed salt solution from magnesium nitrate hexahydrate and aluminum nitrate nonahydrate by using deionized water, reacting, aging and carrying out heat treatment. And the ceramic sand main aggregate is made of zirconium oxide. And all the layers are matched for use to realize balanced improvement of performance.

The invention relates to the technical field of metallurgy, discloses a composite bentonite core material for metallurgical pellets as well as preparation and application of the composite bentonite core material, and aims to solve the technical bottlenecks that the TFe grade is low and the SiO2 content is high due to a large amount of bentonite in existing pellet production, and titanium-containing and high-sulfur fine iron powder pellets are easy to burst and insufficient in strength. The core material is formed by compounding 60% of corn gelatinized starch, 20% of sodium humate, 10% of lignosulfonate and 10% of macromolecular copolymer, and 2%-3% of borax or 2%-3% of polyacrylamide is added for titanium-containing iron fine powder for optimization; 3%-4% of potassium permanganate is added for optimization aiming at the high-sulfur iron fine powder. According to the composite bentonite, the compressive strength of finished product balls can be improved by 20%-30%, the ball cracking rate is reduced by 90% or above, the TFe grade is improved by 0.3%-1.3%, the multiple purposes of reducing the dosage, improving the grade and adapting to special fine powder are creatively achieved, and the composite bentonite has remarkable technical and economic values.

The invention discloses a self-adaptive air pressure regulation and control system of quartz sand unpowered powder selecting equipment, and relates to the technical field of automatic control. According to the method, wind pressure and airflow disturbance signals are collected, a high-resolution map is generated through Hampel filtering and noise reduction, features are extracted through the convolutional neural network, key influence areas are identified, the problem of unstable wind pressure caused by airflow disturbance in a mountainous area is solved, and the particle separation precision is improved; a natural potential energy distribution matrix is constructed based on building floor height difference, velocity field reconstruction and airflow channel optimization are driven, technological parameters are adjusted in combination with a gradient descent algorithm, precise utilization of natural potential energy is achieved, energy consumption is reduced, uneven efficiency is improved, airflow distribution is simulated through a fluid dynamic model, and sedimentation behaviors are analyzed and predicted through particle trajectory. A support vector machine is used for classifying tracks and generating regulation and control instructions, PID control is used for stabilizing air pressure to form a closed loop, the problems that fine powder is mixed with coarse powder, coarse particles are left and the like are avoided, the equipment blockage risk is reduced, and the product purity stability is improved.

The utility model relates to the technical field of dry grinding and dry separation of iron ore and similar processes, and particularly discloses a dry grinding and dry separation system which comprises an incoming material conveying system, a roller mill, a dynamic powder concentrator, a dry classification cabin and a fine powder collecting and conveying system. A discharging hole of the supplied material conveying system is communicated with a feeding hole of the roller mill; a discharging hole of the roller mill is communicated with a feeding hole of the dynamic powder concentrator; a coarse particle material outlet of the dynamic powder concentrator is communicated with a material inlet of the dry type grading cabin; an oversize coarse particle discharging opening of the dry type grading cabin is communicated with a feeding opening of the roller mill; and a fine powder discharge hole of the dynamic powder concentrator is communicated with the fine powder collecting and conveying system. Finished product materials with various particle sizes can be provided, and the requirements of customers for different finished product particle sizes are met; fine powder screened by the dynamic powder concentrator is collected by a dust collector and then is directly conveyed to a tailing discarding procedure, so that the handling capacity of the dry classification cabin is reduced; the use condition of the dry-type grading cabin is optimized, and the system flow is simplified.

The corundum-silicon carbide-mullite castable is prepared from sintered mullite particles, silicon carbide fine powder, activated aluminum oxide micro powder, silicon dioxide micro powder, composite rare earth oxide fine powder, aluminum titanate fine powder, a binding agent, a water reducing agent, explosion-proof fibers and porous composite corundum-silicon carbide particles. The porous composite corundum-silicon carbide particles are formed by sintering fused corundum particles and nano silicon carbide powder through in-situ reaction, micron-sized pore channels which are communicated with one another are formed in the porous composite corundum-silicon carbide particles, and the surfaces of the particles are coated with a compact mullite-corundum complex phase layer, so that thermal stress can be effectively buffered, and permeation of zinc and alkali vapor can be blocked; the low thermal expansion characteristic of aluminum titanate and the grain boundary purification effect of rare earth oxide are matched, thermal shock resistance and erosion resistance are synergistically improved, and excellent thermal shock resistance, chemical erosion resistance, high strength and wear resistance are shown under the harsh working condition of the zinc oxide rotary kiln.

The invention relates to the technical field of fluidized beds, in particular to a fluidization coating device with pulse, stirring and double-particle triple synergy, which comprises a spray fluidized bed reactor, a fluidized bed reactor, a stirring device and a double-particle fluidized bed reactor, the gas distributor is positioned above the carrier gas inlet and is used for uniformly distributing carrier gas entering from the carrier gas inlet on the whole bed layer to form fluidized gas; the gas-liquid two-phase flow nozzle is connected with the gas supply unit and the coating liquid conveying tank and is used for atomizing the coating liquid into micron-sized small liquid drops and then spraying the micron-sized small liquid drops into the spray fluidized bed reactor; the mechanical shearing unit continuously generates local mechanical crushing on the aggregate; the pulse air inlet device is connected with the air supply unit and is used for applying periodic pulse airflow to the fluidized bed layer and breaking particle aggregation and channeling formed during initial fluidization; and the flow aiding particles and the fine powder particles to be coated jointly form a double-particle fluidization system. The problems of difficult fluidization starting, non-uniform fluidization and the like of ultrafine powder particles are solved through triple synergy of pulse, stirring and double particles.

The invention relates to the field of neodymium-iron-boron magnet production processes, in particular to a neodymium-iron-boron magnet preparation method which comprises the following steps: S1, after neodymium-iron-boron leftover materials are classified, cleaned and coarsely crushed, hydrogen decrepitation is carried out, and recycled coarsely crushed powder B is obtained; s2, proportioning and smelting an alloy according to specified requirements, and carrying out hydrogen decrepitation to obtain new material coarsely crushed powder A; s3, after the powder A and the powder B are subjected to airflow milling, a lubricant, an antioxidant and aviation gasoline are added into the powder A and the powder B respectively, stirring and mixing are conducted, and fine powder A and fine powder B are obtained respectively; s4, the fine powder A and the fine powder B obtained in the S3 are mixed and sieved, and mixed powder C is obtained; and S5, the mixed powder C is subjected to magnetic field orientation forming, cooling static pressure, oil stripping and sintering, and finally the neodymium iron boron magnetic material is obtained. According to the method, efficient, economical and environment-friendly recycling of the neodymium-iron-boron magnetic material leftover materials is effectively achieved, and the neodymium-iron-boron magnetic material leftover materials are made into new magnetic materials with the performance reaching the standard again.

The invention discloses a silicon carbide ceramic heat exchange tube and a preparation method thereof, and belongs to the technical field of silicon carbide ceramics. The preparation method of the silicon carbide ceramic heat exchange tube comprises the following steps that a modifier is dispersed in absolute ethyl alcohol, silicon carbide fine powder is added for a reaction, and modified silicon carbide fine powder is obtained; uniformly stirring and mixing phenolic resin, modified benzoxazine and absolute ethyl alcohol, sequentially adding carbon black, fly ash, the modified silicon carbide fine powder and the silicon carbide coarse powder, uniformly stirring and mixing, aging, pugging, carrying out extrusion molding, and drying to obtain a silicon carbide biscuit; and the silicon carbide biscuit is put into a high-temperature furnace for heat treatment, and the silicon carbide ceramic heat exchange tube is obtained. The prepared silicon carbide ceramic heat exchange tube has excellent density, bending strength and fracture toughness.

The invention relates to the technical field of roadbed materials, in particular to a composite filling material and a preparation method and application thereof. The composite filling material provided by the invention is prepared from the following raw materials in parts by weight: 18 to 26 parts of pretreated phosphogypsum, 30 to 45 parts of pretreated household garbage incineration bottom ash, 8 to 18 parts of alkaline excitation material, 6 to 20 parts of aluminum-silicon material, 5 to 25 parts of aggregate and 1 to 4 parts of sodium sulfate aqueous solution, the pretreatment of the phosphogypsum comprises lime milk aging treatment; the pretreated household garbage incineration bottom ash comprises gelation active fine powder and structural aggregate. The composite filling material formed by taking the ardealite, the household garbage incineration bottom ash, the alkaline excitation material and the aluminum-silicon material as main raw materials is high in industrial solid waste mixing amount, stable in performance and environment-friendly, reduces the pollutant leaching risk, is suitable for roadbed structures such as an embankment filling layer, a semi-rigid base layer and a flexible subbase layer, and has a wide application prospect. And the benefit is obvious.

The invention discloses a simple and practical slide sieve, and relates to the technical field of refractory material manufacturing. The simple and practical slide sieve comprises a slide carriage shell, a sieving assembly is arranged in the slide carriage shell, an overhauling assembly is arranged on one side of the slide carriage shell, the sieving assembly comprises a sieve arranged in the slide carriage shell, and lifting lugs are fixedly installed on the two sides of the sieve. The screening problem is solved by the self-gravity of the arranged screening assembly in the using process, only the low-power bin wall vibrator is periodically used for vibration, the cost is remarkably saved, the size is small, the weight is light, installation and maintenance are convenient, the structure is simple, multiple inspection holes are formed in the top of the slide sieve, the sieve net is convenient to overhaul and replace, and sampling and testing are convenient; the vibrating screen device replaces traditional vibrating screen equipment, is obvious in using effect especially in occasions for treating and screening lime or making sand and other fine powder materials, meanwhile, is small in installation space occupied area and light in weight, and can still achieve the screening function under the condition that the space layout is compact.

The invention discloses an additive manufacturing method of a titanium alloy with a double-peak heterogeneous grain structure, which comprises the following steps: in an inert gas protection environment, carrying out layer-by-layer deposition forming on a substrate by adopting powder feeding type laser directional energy deposition equipment, alternately feeding titanium alloy fine powder with the particle size of 20-63 microns and titanium alloy coarse powder with the particle size of 90-150 microns, and after 1-10 layers of powder with the same particle size are deposited every time, the powder with the other particle size is switched to, and the titanium alloy with the double-peak heterogeneous grain structure is obtained after deposition is completed. According to the method, under the conditions that the chemical components of the titanium alloy are not changed, a multi-material interface is not introduced and an external field auxiliary means is not needed, the melting and solidification behaviors are regulated and controlled through the powder particle size difference, layered difference distribution of the grain size is achieved, and then the titanium alloy component with the strength and plasticity cooperatively improved is obtained; and a technical scheme which is simple in process and high in engineering applicability is provided for preparation of the high-performance additive manufacturing titanium alloy component.

The invention discloses a solid waste-based mine filling composite material and application thereof in a separation layer filling treatment system. The composite material is prepared from the following components in percentage by mass: an aggregate component: 30-60% of coal gangue fine powder; a gelling component: 10%-25% of desulfurized gypsum; an activator component: 5%-15% of an alkali activator; and auxiliary components: 5%-15% of fly ash and 0.5%-2% of an early strength water reducing agent. According to the solid-waste-based mine filling composite material and the application of the solid-waste-based mine filling composite material in a bed separation filling treatment system, industrial solid waste is used as a main raw material, an optimized composite system is constructed, and through the synergistic effect of all the components, good balance of slurry fluidity, setting time and early strength is achieved; the obtained slurry has excellent pumpability and stable diffusivity, can effectively permeate and fill separation cracks, is controllable in setting and hardening time, meets the requirements of different engineering scenes, and realizes efficient and high-valued utilization of solid waste resources.

The invention discloses a cement thickness degree detection device, and belongs to the technical field of cement thickness degree detection, the cement thickness degree detection device comprises a cabinet body, a fixed screen seat is arranged on the top side in the cabinet body, and the bottom side in the fixed screen seat is connected with a sealing gasket. A detection worker manually operates a circular plate to drive two arc-shaped sliding blocks, a circular sleeve and an elastic conical cover to move downwards, in the up-down reciprocating motion process of the elastic conical cover, vibration is generated on the surface of the bottom of the elastic conical cover, adhered cement fine particles are effectively shaken off, sample residues are remarkably reduced, and therefore the accuracy of a detection result is guaranteed; in the downward moving process of a circular sleeve, a connecting shaft, a mounting sleeve and a plurality of spoilers are driven to synchronously and slowly rotate under the acting force of a guide rod and an arc-shaped groove, and ordered mild airflow shearing force is formed in the top area of the test screen through the slow rotating motion of the spoilers so as to assist and promote the fine powder penetration phenomenon of the test screen; and the screen analysis efficiency and uniformity of the device are improved.

The invention belongs to the technical field of resource recycling of waste photovoltaic panels, and discloses a green metallurgical method for recycling high-purity silicon, silver and copper from waste photovoltaic panels, which comprises the following steps: (1) disassembling the photovoltaic panels to obtain laminated components, and crushing and screening to obtain light silicon powder and metal-enriched fine powder; (2) leaching the metal-enriched fine powder by using a citric acid-hydrogen peroxide mixed solution; (3) silver ingots are recycled through precipitation and electrolysis; (4) electrolyzing to obtain electrolytic copper; and (5) performing magnetic separation, alkali washing, acid washing, spark plasma sintering and direct-current electric field solidification purification on the silicon powder to obtain the high-purity silicon ingot. A leaching system composed of citric acid and hydrogen peroxide is adopted, so that the method has the advantages of no toxic gas emission, easiness in waste liquid treatment and low cost, and unification of efficient resource recovery and environmental protection is realized.

The invention belongs to the technical field of powder superalloy, and relates to a visual identification-based automatic powder filling method and system for a powder superalloy sheath, and the system comprises a powder vibration system, a powder flow control system, a visual identification system, a comprehensive control system and a hydraulic vibration system. The visual identification system predicts the filling state in real time by collecting morphological characteristics of the powder filling area change rate, the contour regularity and the shadow gray scale, transmits signals to the comprehensive control system, and controls the powder degassing device and the powder conveying mechanism to automatically supplement powder according to the filling state. And the hydraulic vibration mechanism is controlled to adjust displacement, frequency and magnitude to perform compaction operation on the powder in the sheath, and finally automatic powder filling and filling of the sheath are completed. The powder filling state can be automatically recognized, meanwhile, coupling compaction is conducted with hydraulic vibration, the stability of powder distribution control in the filling process is improved, and the problems that in the existing filling technology, fine powder gathering is likely to happen, the manual operation efficiency is low, and powder loss is high are solved.

The invention belongs to the technical field of titanium alloy powder metallurgy, and relates to a low-cost and short-process method for preparing a high-strength titanium alloy workpiece and application. The spherical titanium alloy powder and the non-spherical titanium alloy powder are mixed, so that the compaction and filling density of the mixed powder is improved, densification is more thorough, original particle boundaries can be eliminated or weakened, and adverse effects of impurities or oxides are reduced; further, the problem that the strength is not matched with the plasticity can be avoided by controlling the O content of the spherical and non-spherical titanium alloy powder; by controlling the particle size range of the powder, the problem of multiple original particle boundaries of the fine powder can be avoided, and the risks of slow atomic diffusion and low densification degree of the coarse powder are avoided; the green body is obtained through axial compression before hot isostatic pressing, the initial density of the green body is improved, and the shrinkage amount of the sheath during hot isostatic pressing is reduced, so that the design difficulty of the sheath is reduced, sheath deformation control is facilitated, and the subsequent machining difficulty is reduced.

The application relates to a swing granulator seven-star roller and a mounting structure thereof. The swing granulator seven-star roller and the mounting structure thereof comprise a seven-star roller body, the seven-star roller body is in a cylindrical working surface structure, seven convex granulation corners are uniformly arranged on the outer peripheral wall of the seven-star roller body, the working surfaces of the granulation corners are all arranged in arc structures, and the arc structures are matched with a screen of the swing granulator; a roller mounting mechanism, which comprises a rack, a bearing seat, a bearing arranged in the bearing seat and a rotating shaft penetrating through the bearing, the rotating shaft is connected with an end shaft of the seven-star roller body, the bearing seat is mounted on the rack, a material seepage discharge port is formed in the rack at the bottom of the bearing seat; and a sealing assembly, which is sleeved on the rotating shaft and located at the opening end of the bearing seat. The material can be more fully and uniformly extruded, the hardness of wet particles is effectively improved, the generation of fine powder after drying is reduced, the quality of granular products is improved, the dead angle residual of the material in the equipment is reduced, and the material waste is reduced.

One aspect of the present invention provides a precursor for a negative electrode material of a lithium secondary battery, the negative electrode material prepared from the precursor, and a method for preparing the same, the precursor for the negative electrode material having high capacity characteristics, excellent processability, and excellent lifespan characteristics by a structure in which natural graphite fine powder is distributed in high-hardness artificial graphite.

The invention discloses a high-compaction sodium ion battery negative electrode composite hard carbon material and a preparation method thereof. The preparation method comprises the following steps: S1, asphalt pretreatment: dividing asphalt into a toluene soluble component and a toluene insoluble-pyridine soluble component through a solvent extraction method; s2, precursor mixing: uniformly mixing a toluene soluble component and a biomass raw material to obtain a mixed precursor; s3, pre-carbonization: pre-carbonizing the mixed precursor in a protective atmosphere to obtain a pre-carbonized precursor; s4, crushing and refining: crushing and refining the pre-carbonized precursor to obtain pre-carbonized precursor fine powder; s5, mixing and coating: mixing the pre-carbonized precursor fine powder with a toluene insoluble-pyridine soluble component to obtain a pre-carbonized precursor coated with the toluene insoluble-pyridine soluble component; and S6, high-temperature sintering: carrying out high-temperature carbonization on the pre-carbonized precursor coated with the toluene insoluble-pyridine soluble component in a protective atmosphere to obtain the composite hard carbon material. The preparation method has the characteristics of high compaction density, high first-cycle coulombic efficiency and excellent rate capability.

The utility model discloses a fly ash recycling stirring slurrying device which comprises a tank body, a sealing cover is fixed at the top of the tank body through bolts, a fly ash storage barrel is arranged at the top of the sealing cover, a plurality of material guide pipes are fixed and communicated with the bottom of the fly ash storage barrel, the material guide pipes penetrate through the sealing cover and are fixed with the sealing cover, and the material guide pipes are communicated with the tank body. When fly ash is screened on the bucket-shaped sieve, small-particle fly ash is filtered by the bucket-shaped sieve and then thrown into water in the tank body, the fly ash falls into the water in the form of dispersed powder or fine powder flow, and the powder does not act collectively any more, but takes a single particle or a very tiny particle cluster as a unit. When the fly ash is mixed with water, the fly ash almost falls off or is scattered into the water, so that the production of false aggregates is avoided, the fly ash can be more fully mixed with the water, and the stirring time is shortened and the pulping efficiency is improved due to the fact that no false aggregates exist.

The invention discloses a controlled-release potassium-magnesium fertilizer as well as a preparation method and application thereof, and relates to the technical field of controlled-release fertilizer production. Potassium magnesium crude salt recovered through salt lake carnallite flotation crystallization is used as a core raw material, high-roundness modified potassium magnesium salt composite particles are constructed through extrusion master batch forming, roller wet amplification, centrifugal polishing shaping and micropore filling and sealing, and the controlled-release potassium magnesium fertilizer is prepared through coating. The problems that potash fertilizer particles prepared through traditional extrusion granulation have many edges and corners and are not prone to film coating are solved through a multi-stage granulation process, secondary granulation is conducted through heterogeneous fine powder materials, surface micropores are filled, the surface smoothness of the particles is greatly improved, meanwhile, the influence of potassium ions on film forming is isolated, and the potassium fertilizer has the good application prospect. According to the finally prepared controlled-release potassium-magnesium fertilizer, a nutrient release curve is precisely regulated and controlled through the controlled-release film layer, double-nutrient continuous supply of crops with high potassium and high magnesium requirements is achieved, the potassium and magnesium deficiency symptoms of the crops are reduced, the crop quality is improved, and a core technical support is provided for high-value utilization of salt lake potassium ore resources and green quality improvement of the crops.

The invention discloses an automatic device and method for micro powder multi-stage screening. According to the centrifugal bottle, the mechanical arm assembly and the centrifugal device are arranged, the traditional complicated process flow of manual screening-filtering-secondary screening is omitted, the labor cost is saved, the screening method is optimized, and the optimized centrifugal bottle comprises the centrifugal bottle body, the centrifugal bottle upper assembly and the centrifugal bottle lower assembly; the centrifugal bottle upper assembly and the centrifugal bottle lower assembly are connected to the upper end and the lower end of the centrifugal bottle body through threads correspondingly, the three clamping jaws are controlled and driven by the pneumatic component, screwing and unscrewing actions of the centrifugal bottle upper assembly and the centrifugal bottle lower assembly can be achieved, the requirements for convenience and automation of the multi-stage screening process can be met, and the screening efficiency is improved. And automatic fine multi-stage screening under the micro-powder particle size distribution index is realized.

The utility model discloses a silicon carbide micro powder stirring dispersion device, including inner tube and outer tube, the top fixed mounting of inner tube has first motor, and first motor output is fixed with the stirring paddle through the shaft coupling, in the utility model, adopt inner tube and outer tube to constitute silicon carbide micro powder stirring dispersion device, through starting first motor work, promote first motor to drive its output end's stirring paddle rotation, make the stirring paddle surface installation's stirring rod rotate, because the bottom of every stirring rod is welded with the dispersion board of comb tooth shape, and the U -shaped gap of dispersion board corresponds with the conical spine of auxiliary stirring rod surface, along with the rotation of stirring paddle, the dispersion board of stirring rod and the conical spine of auxiliary stirring rod are to silicon carbide micro powder and are stirred and carded, at this moment, start second motor and drive its output end's gear intermittent positive and negative rotation, because the gear ring of inner tube outer wall is engaged connection with gear, and the ball bearing is installed between inner tube and outer tube, make the gear drive inner tube intermittent positive and negative rotation.