1404 results about "Roasting" patented technology

The invention relates to the technical field of anode carbon block roasting, and discloses an energy-saving control system of an anode carbon block roasting furnace, which comprises a data acquisition module, an energy-saving analysis module, a digital twin modeling module, a control execution module and a feedback optimization module, when the combustion state of the roasting furnace is monitored in real time, a multi-layer monitoring framework is constructed to dynamically track the change trend of temperature, flue gas oxygen content and pressure parameters, continuous comparison is performed based on a preset energy-saving reference interval, and when the parameters deviate from an optimization interval, a digital twinborn model is immediately triggered to intervene in analysis, so that the real-time monitoring of the combustion state of the roasting furnace is realized. Prejudgment identification of potential risks of combustion efficiency reduction and abnormal heat loss is achieved, hidden energy loss caused by imbalance of the air-fuel ratio is avoided, the non-planned shutdown frequency of equipment is reduced, and the continuous energy efficiency management and control stability of the production process is guaranteed.

According to the method for gradient separation of the heavy metal in the household garbage incineration fly ash, the composition and content of the household garbage incineration fly ash are detected in advance, and grinding pretreatment is conducted on the household garbage incineration fly ash; a plurality of reaction temperature intervals corresponding to various heavy metals in the household garbage incineration fly ash are arranged in a heating furnace, the household garbage incineration fly ash is subjected to multi-stage heating roasting, and chlorine element compounds contained in the household garbage incineration fly ash react with the heavy metals under the high-temperature condition to be volatilized, so that heavy metal chloride gas is obtained; a certain amount of protective gas is introduced into the heating furnace in each reaction temperature interval to prevent the unvolatilized heavy metal chloride from being oxidized, and finally all heavy metals are successfully separated out; a plurality of condensation temperature sections are arranged in the sectional condensation pipe, heavy metal chloride is recycled step by step at different condensation temperatures, and separation and recycling of different heavy metals are achieved; according to the scheme, complex operation procedures can be avoided, energy consumption is reduced, and the method has remarkable economic and social benefits and wide application prospects.

The invention belongs to the technical field of tungsten smelting, and particularly discloses a method for recycling tungsten from tungsten smelting soda boiling slag through reselection, tungsten in the slag is recycled through a physical mineral separation method, a large number of acid-base reagents are not introduced, acid-base wastewater is not generated, and high-energy-consumption roasting or high-temperature acid-base leaching is not needed. The process is simple, large-scale treatment can be achieved, reagent consumption is low, energy consumption is low, closed-loop circulation of mineral separation water can be achieved, no wastewater is discharged, the process is environmentally friendly and free of pollution risks, meanwhile, indexes of the soda boiling residues subjected to innocent treatment can reach industrial solid waste, hazardous waste is converted into common solid waste, and the economic benefit is high. The environment-friendly treatment cost is low.

The invention discloses a method for preparing a bismuth ferrite composite catalytic material by using red mud as well as a product and application of the bismuth ferrite composite catalytic material. The method comprises the following steps: mixing chlorine salt and red mud, uniformly stirring, adding a hydrochloric acid solution, uniformly stirring, roasting, recovering flue gas generated in the roasting process, and obtaining roasting residues and roasting dust generated by recovering the flue gas after roasting is finished; and mixing the roasted dust and bismuth nitrate, uniformly stirring, adding the calcined residue, uniformly grinding, adding water, stirring, drying the material, and calcining to obtain the bismuth ferrite composite catalytic material. The preparation process is simple, the red mud is used as a main raw material, and full-amount resource utilization of the red mud can be achieved. The prepared composite catalytic material can be used for efficiently purifying landfill leachate, and COD, ammonia nitrogen, total phosphorus and heavy metal pollution are efficiently removed through a photocatalysis mechanism.

The invention discloses a high-oxygen-storage zirconium solid solution material and a preparation method, and belongs to the technical field of rare earth catalytic materials, and the method comprises the following steps: precursor preparation, ultrasonic dispersion, double-gradient precipitation, ultrasonic aging, solid-liquid separation, three-section roasting and furnace cooling. Through the synergistic effect of double-gradient precipitation and ultrasonic aging, coarse grains and non-uniform particle size distribution are avoided, and the material is not prone to abnormal growth of the grains and structural collapse in long-term high-temperature service. Meanwhile, according to the gradient roasting process, through step-by-step regulation and control of crystal densification and crystal lattice reconstruction, separation of a fluorite phase and a pyrochlore phase easily occurring in traditional low-temperature single-section roasting is reduced, a stable crystal phase structure is maintained, it is ensured that the material can still keep sufficient active surface and pore channel structures under the working conditions of high temperature and thermal shock alternation, and the performance of the material is improved. The oxygen storage capacity and the long-term durability of the catalyst carrier are obviously improved.

The invention provides a method and equipment for producing Li2CO3 based on coordinated roasting of lepidolite and spodumene. The method for producing Li2CO3 based on coordinated roasting of lepidolite and spodumene comprises the steps that S1, ore pretreatment is conducted, specifically, lepidolite and spodumene with the particle size smaller than 5 mm are evenly mixed according to the mass ratio of 1: (1-3), and the mixed ore is finely ground till the particle size is smaller than 75 microns; s2, additive mixing, wherein a composite additive is added into the mixed ore obtained after fine grinding and evenly mixed with the ore, and the composite additive is composed of fluoride, sulfate and a fluxing agent; and S3, coordinated roasting, wherein the mixed materials are fed into a rotary kiln to be roasted. According to the method for producing Li2CO3 based on coordinated roasting of the lepidolite and the spodumene, the lepidolite and the spodumene are roasted in a coordinated mode, the structural and chemical property differences of the lepidolite and the spodumene are utilized, advantage complementation is achieved, the overall extraction rate of lithium is increased, compared with a single lithium extraction technology, the lithium recovery rate can be increased by 10%-20%, and the waste residue generation amount is reduced.

The invention discloses a method for preparing ultra-high-purity quartz by multi-stage synergistic purification of quartz ore, and belongs to the technical field of ultra-high-purity quartz preparation. According to the method, natural quartz ore is used as a raw material, mineral impurities, lattice impurities and inclusions in quartz are deeply removed through multi-stage synergistic processes such as low-temperature plasma activation, biological leaching, supercritical CO2-assisted acid leaching, microwave-assisted chloridizing roasting and pulsed electric field enhanced acid leaching, and finally a high-purity quartz product with the SiO2 purity larger than or equal to 99.998% (4N8 grade) is obtained. According to the invention, a low-temperature plasma activation technology, microbial metallurgy, supercritical fluid extraction and a pulsed electric field strengthening technology are organically combined, so that the energy efficiency bottleneck and environmental protection limitation of a traditional high-purity quartz preparation process are broken through; the obtained quartz sand product can reach the standards of high-purity quartz sand for semiconductor quartz glass and high-purity quartz sand for photovoltaic quartz crucibles.

The present invention relates to the technical field of alumina production. The present invention discloses a waste heat recovery device for a roasting furnace, which comprises a flue gas fan, a heat exchange pipeline and an exhaust hood. A flue gas pipeline is arranged at the inlet of the flue gas fan and communicated with an external roasting furnace. The outlet of the flue gas fan is communicated with a plurality of heat exchange pipelines. The top ends of the heat exchange pipelines are jointly communicated with the exhaust hood. A flue gas outlet pipe is arranged at the top of the exhaust hood, and an outlet valve is arranged on the flue gas outlet pipe. It is characterized in that: a converging throat is arranged in the middle of the heat exchange pipeline, and a diffusor wall with horizontal displacement is arranged above the throat. The advantages of the present invention compared with the prior art are as follows: by performing heat exchange while pressurizing the flue gas flow, the water vapor contained in the flue gas can be liquefied and release heat, and its latent heat of vaporization can be fully released and absorbed. For the field to which the present invention is applied, the latent heat of vaporization can be used to heat mother liquor and flat plate washing water, saving the steam cost for heating flat plate washing water, reducing energy consumption and reducing emissions.

The invention discloses a preparation technology of isostatic pressing graphite. The preparation technology comprises the following steps of S1, raw material and ingredient pretreatment, S2, grinding, S3, mixing and kneading, S4, forming, S5, roasting, S6, dipping, S7, graphitization, S8, processing and detection and S9, finished product packaging. A graphite grinding machine used for primary grinding in the step S2 is a vertical roller mill; and a graphite mill used for secondary milling is an airflow mill. The kneading machine in the step S3 is a heating type kneading machine. And in the step S4, the vacuumizing time is 0.5 h, and the vacuum degree is 0 to-0.06 MPa. The roasting furnace in the step S5 is a rotary graphite roasting furnace.

The graphitized product secondary roasting charging and discharging process comprises the following steps that S1, a high-purity graphite support or a multi-layer support structure is arranged in a hearth of a graphite furnace, and a graphite product is hoisted to the graphite support or the multi-layer support through a special clamp for charging; s2, sectional heating is adopted, the heating process is divided into a low-temperature section, a medium-temperature section and a high-temperature section, and the heating rate of each stage is controlled; s3, after roasting is completed, natural cooling is conducted, and after the temperature is reduced to the preset temperature, products are discharged out of the furnace; s4, the graphite product is clamped through a special clamp to be lifted out of the furnace, and in the step S1, the graphite product is vertically arranged on the graphite support and is arranged on the multi-layer support structure in a layered mode; when the secondary roasting charging and discharging process for the graphitized product is used, the stability and roasting uniformity of the product in a hearth can be guaranteed, segmented heating roasting is carried out in the furnace, graphite product cracking or performance reduction caused by temperature fluctuation can be avoided, the product quality is guaranteed, and the secondary roasting charging and discharging process for the graphitized product is suitable for application and popularization.

This application relates to the field of ceramsite, and specifically discloses a preparation process for two-stage water-retaining ceramsite from coal gangue. The preparation process includes green pellet preparation, drying section, pyrolysis section, decarbonization section, first roasting section, soaking section, second roasting section, and cooling section; the green pellet preparation includes: wetting coal gangue powder with an organic solution, stirring evenly, and kneading with biomass material. The mass ratio of coal gangue powder to biomass material is 1 kg:(3-9) g to obtain green pellets; the soaking section includes: transferring the green pellets after the first roasting section to the soaking section, with the material layer temperature below 900 °C, and evenly spraying nano-silica during the transfer process, spraying 1-2.5 g per 100 g of green pellets; the cooling section includes: using one of sodium bicarbonate solution, ammonium bicarbonate, and ammonia water to form a water mist mixed with air to cool the roasted ceramsite. The prepared ceramsite has a rich and gradient pore structure, can quickly absorb water, and has excellent water-retaining performance.

The invention provides a method for purifying waste battery black powder acid-leached graphite slag, which comprises the following steps: (1) mixing waste battery black powder acid-leached graphite slag and sulfuric acid to obtain a mixture; (2) roasting the mixture obtained in the step (1) to obtain a roasted material; and (3) the roasted material in the step (2) is subjected to leaching and solid-liquid separation in sequence, and a leaching solution and purified graphite with the fixed carbon content larger than or equal to 99.8% are obtained. According to the scheme provided by the invention, roasting is performed after the sulfuric acid is loaded, so that the waste battery black powder acid leaching graphite slag is purified, the operation is simple, and the purification effect is good.

The invention discloses a high-temperature dechlorinating agent for removing hydrogen chloride gas and a preparation method of the high-temperature dechlorinating agent, and belongs to the technical field of dechlorinating, and the preparation method of the high-temperature dechlorinating agent for removing the hydrogen chloride gas comprises four steps of preparing sepiolite-loaded active calcium powder, preparing copper-aluminum coated calcium carbonate whiskers, forming and roasting. According to the high-temperature dechlorinating agent for removing the hydrogen chloride gas, the penetration chlorine capacity is 78.5 to 81.7 percent, the crushing strength is 142 to 160N. Cm <-1 >, and the abrasion rate is 0.8 to 1.2 percent.

The invention belongs to the technical field of rare earth metallurgy and resource comprehensive utilization, and particularly relates to a method for separating and recycling iron and rare earth elements in rare earth iron ore. According to the method for separating and recycling the iron and the rare earth elements in the rare earth iron ore, the iron and the rare earth elements in the rare earth iron ore are recycled through MgO reduction roasting, and the efficient separation and extraction process of the iron and the rare earth elements is achieved by adding additives such as a reducing agent and MgO and through the procedures of reduction roasting, magnetic separation, selective leaching and selective precipitation. And comprehensive utilization of the rare earth-containing iron ore can be effectively realized.

The invention relates to the field of precision casting, and discloses a precision casting process for a stainless steel impeller for nuclear power, which comprises the following steps of: S1, pressing a wax mold by using an investment casting process, and connecting the wax mold into a tree shape by using a wax rod; s2, the surface of the wax mold is coated with a refractory material, dewaxing is conducted through dewaxing equipment after drying, a hollow shell is obtained, and then high-temperature roasting is conducted; s3, selecting duplex stainless steel to be smelted in an electric furnace, heating molten steel to a preset pouring temperature, and pouring the molten steel into the shell from the bottom or the side; s4, the shell is removed after being naturally cooled, and solution treatment is conducted on the impeller; s5, carrying out sand blasting, shot blasting and sand cleaning, and carrying out nondestructive inspection; wherein dewaxing equipment used in the step S2 comprises a tank body, a rotatable tray is arranged in the tank body, and a plurality of adjustable fixing clamps are arranged on the tray to meet the fixing requirements of different shells; the top of the tank body is provided with a feed port, a discharge port and an automatic sealing door, and the bottom is connected with a wax liquid collecting tank and is internally provided with a liquid level sensor; the inner wall of the tank body is provided with a heating cavity for containing heating elements, and the outer wall is wrapped with heat insulation materials.

The invention discloses a method for preparing high-purity iron phosphate through low-cost aluminum removal of ferrophosphorus slag obtained after lithium extraction of waste lithium iron phosphate batteries. The method comprises the following steps that S1, the ferrophosphorus slag is subjected to size mixing, a complexing agent and a leaching agent are added, and leaching liquid 1 and leaching slag 1 are obtained after filtering and washing; s2, mixing the leachate 1 with a pH regulator 1, and filtering to obtain molten aluminum and purified ferrophosphorus slag; s3, the purified ferrophosphorus slag is subjected to acid pickling, filtering and washing, and then acid-pickled ferrophosphorus slag is obtained; s4, the leaching residues 1 are subjected to size mixing and stirring washing, and stirring washing residues are obtained; s5, slurry mixing is conducted on the stirring and washing residues, acid is added for dissolution, and leachate 2 and graphite residues are obtained after solid-liquid separation; s5, mixing the acid pickling ferrophosphorus slag with the leachate 2, and filtering to obtain regenerated ferrophosphorus liquid; and S6, a pH regulator 2 is added into the regenerated ferrophosphorus liquid, a regenerated iron phosphate product is obtained through synthesis, conversion and roasting, and efficient removal of aluminum impurities in the leachate is achieved under the conditions of short process and less acid through the processes of adding a complexing agent for acid leaching, precipitating, dissolving and the like.

The invention particularly discloses a deep removal method for lattice impurities and inclusion in high-purity quartz sand. The method comprises the steps of calcination water quenching, ultrasonic acidification, first-stage roasting, second-stage roasting, secondary water quenching, hot-pressing acid leaching and cleaning and drying. According to the method, through calcination water quenching, ultrasonic acidification, two-stage roasting, secondary water quenching and hot-pressing acid leaching, lattice impurities and tiny inclusion bodies in the high-purity quartz sand can be deeply removed, the purity of the purified quartz sand reaches 4N8 and even 5N grade or above, and then the technical problems existing in the prior art are solved.

The invention belongs to the technical field of clay type lithium ore dressing and smelting, and particularly relates to a grinding and leaching integrated gradient lithium extraction method for clay type lithium ore (containing lithium in an adsorption state and an independent mineral state at the same time), which comprises the steps of ore grinding, pretreatment roasting, grinding and leaching integration and agitation leaching. Wherein in the grinding and leaching integrated process, sulfuric acid or ferric sulfate is added during ore grinding, and a lithium leaching solution a with low impurity content is obtained after solid-liquid separation; in the agitation leaching process, sulfuric acid is used for leaching the leaching residues a, lithium leaching liquid b with the high impurity content is obtained, and the method is high in lithium extraction rate and recovery rate, classification and impurity removal of the leaching liquid are easy, and generated waste water is convenient to treat and utilize. According to the method, the raw ore treatment capacity of the roasting procedure is effectively improved, the energy consumption of lithium carbonate production is reduced, meanwhile, sulfuric acid enhanced leaching of all roasted materials of clay type lithium ore in a complex occurrence state is avoided, the use amount of sulfuric acid and the impurity removal cost of the leachate are effectively reduced, and cost reduction and efficiency improvement are obvious.

The invention provides a clay type lithium ore-lepidolite-spodumene continuous induction suspension cascade roasting lithium extraction method, which comprises the following steps: mixing clay type lithium ore and lepidolite concentrate for pelletizing, then mixing with spodumene concentrate to obtain a clay type lithium ore-lepidolite-spodumene mixed material, and carrying out continuous induction suspension cascade roasting on the clay type lithium ore-lepidolite-spodumene mixed material to obtain the clay type lithium ore-lepidolite-spodumene powder. And carrying out gradient high-temperature roasting, low-temperature acidizing roasting and water leaching to obtain a lithium leaching solution. The leaching rate of lithium in the lithium leachate obtained through the lithium extraction method is larger than or equal to 90%, the problem that existing spodumene roasting crystal transformation temperature is high can be effectively solved, meanwhile, the extraction and utilization rate of lepidolite and clay type lithium ore is increased, integrated extraction and utilization of lithium resources are achieved, and the method is simple in process, low in energy consumption, low in cost, easy to industrialize and suitable for industrial production. Good application prospects are realized.

The invention discloses a high-valued utilization method of waste biomass, which comprises the following steps: firstly, applying current to the waste biomass containing carbon element to generate Joule heat, and generating a high-temperature environment in an extremely short time, so as to realize rapid carbonization of the biomass; then conductive carbon black or other auxiliaries do not need to be additionally added, current is applied again to generate Joule heat, a higher-temperature environment is generated within an extremely short time, and graphitization transformation of the biochar is achieved. Compared with traditional pyrolysis, hydrothermal, roasting or chemical vapor deposition methods, the flash Joule thermal method has the advantages of being easy and convenient to operate, short in consumed time, low in energy consumption, high in efficiency, high in safety, environmentally friendly and the like, and is suitable for high-value utilization of various biomass resources and green preparation of graphene materials.

The invention relates to the technical field of lithium recovery, and in particular to a comprehensive utilization process of low-grade clay-type lithium resources, comprising the following steps: S1. grinding raw ore into fine particles, and then sequentially performing constant temperature roasting, constant temperature acid leaching, filtering and washing to obtain leaching residue and leaching solution; S2. adding ammonium sulfate to the leaching solution, filtering to obtain a crude ammonium aluminum sulfate product and a crystallization tail liquid; S3. adding new acid and water to the crystallization tail liquid, and then using it for constant temperature acid leaching again; S4. repeating steps S1-S3 for many times to obtain a lithium-rich crystallization tail liquid; S5. concentrating the lithium-rich crystallization tail liquid, adding NaOH to remove impurities, and then evaporating and concentrating, cooling, crystallizing and filtering to obtain sodium sulfate crystals; S6. precipitating lithium carbonate on the lithium-rich crystallization tail liquid; the aluminum in the leaching solution of the invention is efficiently separated, and an ammonium aluminum sulfate product is prepared; the lithium resources are effectively enriched, and finally a green and efficient comprehensive utilization process of clay-type lithium ore with almost no tail and no wastewater discharge is realized.

The invention provides a method for extracting lithium, rubidium and cesium through strengthened roasting of lepidolite and preparing lithium, rubidium and cesium salt, and belongs to the technical field of lithium, rubidium and cesium extraction.The method comprises the steps that lepidolite, a carbon / sulfur additive and chlorine salt are subjected to ball milling, roasting and grinding, and roasted sand is obtained; through thermodynamic analysis on the lepidolite, after the carbon / sulfur additive is introduced, the Gibbs free energy of the reaction of the lepidolite and the additive is reduced, the reaction trend is improved, and in the roasting process, ions such as sodium, potassium and calcium in chlorine salt and the carbon / sulfur additive are replaced in a similar isomorphic manner, so that lithium, rubidium and cesium are leached more easily; in the process of intensifying roasting by introducing the carbon / sulfur additive, the use amount of the chlorine salt additive is reduced by 10-25%, potassium-sodium mixed salt and calcium oxalate are recycled, the recycling rate is greater than 50%, and the leaching residue amount is reduced by 30-40%; and the carbon / sulfur additive can directionally promote the reaction of the calcium salt additive and the lepidolite and convert the calcium salt additive into dicalcium silicate, so that the leaching residues obtained in the subsequent leaching process are easier to recycle.

The invention discloses a method and device for automatic roasting and process intelligent control of a belt type roasting machine, and relates to the technical field of pellet roasting of the belt type roasting machine in the metallurgical iron and steel industry. The method comprises the four steps of historical data slice acquisition and modeling, target process parameter determination, feedback verification and online correction and rolling prediction control, a model historical library is established through service slices and time slices, modeling is performed based on a three-layer feed-forward neural network, flexible weighted deviation calculation combined with dynamic weight and rolling optimization of a softening coefficient are combined, and the rolling prediction control is performed. And accurate regulation and control of equipment parameters are realized. The automatic control system is mainly used for automatically controlling the pellet production process of the belt type roasting machine, the product quality stability is improved, the energy consumption is reduced, the labor intensity of workers is relieved, and support is provided for unmanned and intelligent production.

The invention relates to the technical field of synthetic quartz sand, in particular to an ultrapure synthetic quartz sand roasting device which comprises a temperature acquisition unit, a plurality of reaction temperature sensors arranged on the inner side of the furnace wall of a reaction furnace and used for acquiring the temperature of each temperature control area, and a gas temperature sensor, the data acquisition unit comprises a plurality of machine vision devices and a signal detection device, wherein the machine vision devices are used for acquiring the reaction time of each temperature control area; the data analysis unit is used for determining a plurality of same quartz sand roasting characteristic values as a quartz sand roasting characteristic value group, and calculating diffraction peak dispersion characteristic values to determine a target quartz sand roasting characteristic value; the data processing unit is used for judging whether the quartz sand raw material is uniformly dispersed in the reaction furnace; and the finished product detection unit calculates the temperature difference threshold value and the temperature deviation value of each temperature control area to judge whether the reaction furnace works normally or not. According to the method, the roasting accuracy of the ultra-pure synthetic quartz sand is remarkably improved.

The invention discloses a method for recycling laterite-nickel ore metallurgical slag resources, and belongs to the technical field of hydrometallurgy. The method comprises the following steps: carrying out alkaline leaching treatment on the laterite-nickel ore hydrometallurgical slag to obtain alkaline leaching liquid and alkaline leaching slag; carrying out acid leaching treatment on the alkaline leaching residues to obtain acid leaching liquid and acid leaching residues; mixing the acid leaching residues, a biomass reducing agent and an additive, performing primary ball milling treatment, and performing reduction roasting treatment on an obtained product to obtain a roasted product; and mixing the roasted product with a dispersing agent, carrying out secondary ball milling treatment, and carrying out magnetic separation on the obtained product to obtain iron ore concentrate. According to the method, the biomass is carbonized and activated to obtain the biomass reducing agent with enhanced reducibility, the biomass reducing agent is low in cost and environmentally friendly, the biomass reducing agent and the acid leaching residues are continuously mixed according to a specific proportion, reduction roasting is carried out under a specific atmosphere, and then magnetic separation is carried out; and iron ore concentrate with relatively high purity and yield is obtained.

The invention discloses an extraction method for extracting gallium from waste residues of coal gangue and bauxite, which is characterized in that metal elements such as gallium and aluminum in the waste residues can be uniformly distributed through powdering and proper mixing, ammonium sulfate is added in the roasting process, so that not only is the separation and release of gallium and aluminum realized, but also the generated ammonium sulfate gas is cooled, crystallized and recycled, and the production cost is reduced. According to the method, the process cost is reduced, acid leaching, alkaline leaching and composite extraction are adopted step by step, it is ensured that gallium is efficiently enriched and separated in all procedures, gallium oxide with the purity larger than or equal to 99.5% is finally obtained, meanwhile, residual silicon-rich residues and bauxite residues are subjected to hydrothermal crystallization to prepare molecular sieves, comprehensive utilization of waste residues is achieved, and obvious economic and environment-friendly benefits are achieved.

The invention discloses a process for extracting lithium from lepidolite through low-temperature roasting, which comprises the following steps: uniformly mixing lepidolite mineral powder with ferrous sulfate, sodium sulfate and calcium oxide, roasting at 800-900 DEG C for 1-2 hours, and cooling to room temperature to obtain a roasted material; adding water into the roasted material to prepare slurry, performing wet grinding to obtain ball-milled slurry, performing water leaching on the slurry, and performing suction filtration to obtain lithium sulfate leaching liquid and leaching residues; treating the leaching solution to obtain a lithium precipitation pre-solution, and further carrying out lithium precipitation reaction to obtain a lithium carbonate crude product; and finally, mixing the crude lithium carbonate product with deionized water, heating, stirring, washing and carrying out solid-liquid separation to obtain a battery-grade lithium carbonate product. The lithium extraction process of the lepidolite can be realized under the roasting condition of 800-900 DEG C, and the roasting temperature is effectively reduced; meanwhile, on the basis of the low-temperature roasting condition, Li2SO4 and LiKSO4 can still be extracted to the maximum extent, and release of SO2, SO3 and HF is avoided.

The invention relates to the technical field of coal gangue resource utilization, in particular to a magnetic coal series kaolin hydrogel adsorbing material as well as a preparation method and application thereof. The preparation method of the material specifically comprises the following steps: carrying out ultrafine grinding, sieving and grading on coal gangue ore to obtain a coal series kaolinite material; further performing magnetic separation to obtain coal series kaolinite iron-rich tailings; further performing magnetizing roasting in a reducing atmosphere to obtain magnetic coal series kaolin; the preparation method comprises the following steps: compounding magnetic coal series kaolin with sodium alginate and chitosan by adopting a gel coating method, dropwise adding a calcium chloride solution for crosslinking, and freeze-drying to obtain the magnetic coal series kaolin hydrogel material. The preparation method is simple, and the obtained adsorption material has the characteristics of low cost, large adsorption capacity, high adsorption rate, high selectivity, excellent cyclic utilization performance and the like.

The invention discloses a secondary roasting device and roasting method for graphite electrode production, and belongs to the technical field of graphite electrode roasting devices.The secondary roasting device for graphite electrode production comprises a furnace body and two sliding rails arranged on one side of the furnace body, and a bottom plate is assembled on the sliding rails in a sliding mode; the bearing plate can be pulled out of the furnace body through cooperation of the hook plate and the connecting groove, when a new bearing plate falls onto the inner barrier strip and the outer barrier strip, the reversing assembly can release the locking relation with the inner barrier strip, then the pulling force direction of the auxiliary steel cable on the guide block is changed, the auxiliary steel cable can pull the bottom plate to gradually get close to the furnace body, and therefore the furnace body is protected. And the bearing plate is pushed into the furnace body through the ejector rod, manual intervention is little in the whole process, so that the process of entering and exiting the furnace is safer, the whole operation is completed only through cooperation of the main steel cable and the auxiliary steel cable, and the device is simple in overall structure and convenient to maintain.

The invention discloses gel curing forming equipment and a preparation device and method of high-purity sandy silicon dioxide, and belongs to the technical field of chemical production. The preparation method provided by the invention solves the problems that the gel particles are easy to crack and flake, secondary crushing and purification are needed after drying or roasting, the transparency is poor and the like in the existing traditional process mode. Gel particles which are free of cracks and good in circularity are obtained through designed gel curing forming equipment in combination with a technological gelation method and an integrated drying mode, and then the high-purity sandy silicon dioxide which is low in hydroxyl, high in purity and suitable in particle size and has closed pores is obtained through a sintering mode, so that the method is rapid, effective, high in universality and suitable for large-scale production. The preparation method can be well applied to industrial large-scale production of the high-purity silicon dioxide material.