150results about How to "Shorten roasting time" patented technology

The invention discloses a ceramic core for silica sol precision casting and a manufacturing process thereof. Main body components of the ceramic core comprise refined quartz powder and a proper amount of collapsing agent, and the surface of the ceramic core is coated with high-temperature resistant paint with a thickness of 0.1 to 0.2 millimeter; and at the same reasonable manufacturing processes such as mixing, core making and roasting are adopted. In the ceramic core for casting, the unique material mixing and manufacturing processes are adopted, and the reasonable use of the refined quartz powder and the collapsing agent improves the collapsibility of the ceramic core after casting considerably, the high-quality high-temperature resistant material in ingredients enables the core to resist the erosion of high-temperature molten metals, and the high-temperature resistant paint on the surface of the ceramic core not only improves the high temperature resistance during casting, but also increases the cooling speed of the molten metal.

The invention relates to shell powder and a preparation method thereof. The invention provides the high-quality shell powder and solves the technical problems of reducing the baking temperature, shortening time and reducing energy consumption. The preparation method of theshell powder comprises the following steps of: washing ruditapes philippin (known as ruditapes philippinarum in the southern part of China, clam in Liaoning province, China, and surf clam in Shandong province, China), clams, oysters, scallop and conchs, drying, pulverizing, adding an auxiliary agent, mixing, baking, grinding, and sifting to prepare powder; determining that the powder has the main component of CaCO3 and a small amount of CaO by using an infrared spectrograph, a powder X-ray spectrograph and a specific surface measurement device; placing in the air; and then converting CaO to [Ca(OH)2]. The shell powder belongs to calcite type crystal, can be used as a natural material and for replacing a chemical product and has broad application prospect.

The invention relates to a method for extracting rare earth from rare earth tailings, and belongs to the technical field of mineral extraction metallurgy. The method comprises the following steps of: (1) mixing the rare earth tailings and a carbon-containing reducing agent uniformly in a certain ratio, and roasting the mixture for 8 to 20 minutes in a microwave roasting oven; (2) performing magnetic separation on the roasted product in a weak magnetic separation tube to separate magnetic iron minerals so that the rare earth minerals are enriched in the tailings; and (3) treating the rare-earth-containing magnetic separation tailings by using a flotation method so as to realize effective extraction of the rare earth. The method has the advantages of short roasting time, low consumption of the reducing agent, energy and a flotation agent, and good flotation effect, can be used for realizing selective reduction of the iron minerals in the reducing process and eliminating environmental pollution caused by the tailings, and is economic and environmentally friendly. The iron mineral impurities such as S, P and the like obtained by the magnetic separation are fewer, the grade of the iron mineral is more than 60 percent, the iron mineral can be used for making iron, the rare earth oxide content of the mineral obtained by primary flotation is 34.12 percent, and the grade of the mineral can reach over 50 percent by concentration.

The invention relates to a method for extracting niobium from tailings, belonging to the technical field of mineral extraction metallurgy. The method includes the steps as follows: (1) treating the tailings with a flotation method so as to float out iron and niobium minerals from the tailings; (2) using a microwave magnetizing-roasting method and adding carbonaceous reducing agent in the floated minerals so as to convert the haematite in the minerals into magnetite; (3) separating the magnetite out from the roasted minerals by adopting a low-intensity magnetic separation method, thus enriching the niobium minerals in the tailings subjected to magnetic separation; and (4) leaching the obtained niobium minerals out in a high-pressure kettle with concentrated acid so as to obtain niobium-containing extract. The method flow is short, flotation agent types are few and the flotation effect is good; the mineral roasting time is short, the consumption quantity of reducing agent is less and the cost is low; the content of hazardous elements such as S, P and the like in the magnetite obtained by low-intensity magnetic separation is low simultaneously when niobium is enriched, niobium is an excellent material for making iron with a blast furnace, and environment pollution caused by the tailings is solved to a large extent.

The invention discloses a method for preparing a casting shell of a fire mold. The method comprises a surface layer preparing step, a transition layer preparing step, a back layer preparing step, a dewaxing step and a roasting step. According to the method for preparing the casting shell of the fire mold, the roasting time of the shell is shortened, the roasting temperature of the shell is reduced, and energy can be saved; and the residue strength of the shell is reduced, the shell removing performance of the shell is improved, cleaning of the shell after casting is facilitated, and the production efficiency is improved.

The invention discloses a method for extracting beryllium oxide from low-grade beryllium ore. The method is characterized by comprising the following steps of: grinding the low-grade beryllium ore, pelletizing, drying, roasting, and crushing to obtain a roasted material; adding concentrated sulfuric acid, stirring, leaching, and separating to obtain acidified liquid and acidified slag; adding the acidified liquid into the other roasted material, and stirring and leaching to obtain primary steep and primary leaching residue; adding concentrated sulfuric acid into the primary leaching residue, adding water, and stirring and leaching to obtain secondary steep and secondary leaching residue, wherein the acidified liquid is replaced by the secondary steep for recycling; extracting the primary steep by adopting an extracting agent in a volume ratio of phosphors extracting agents: alkanol: kerosene of (25-45):(5-1):(50-70) to obtain a beryllium-loaded organic phase and raffinate; washing the beryllium-loaded organic phase by adopting solution of oxalic acid, and performing back extraction by using solution of NaOH to obtain a blank organic phase and stripping solution; and regulating the concentration of hydroxyl ions in the stripping solution to ensure that beryllium is hydrolyzed and precipitated, and calcining a precipitate to obtain the beryllium oxide. The method is easy to operate, the cost is low, the beryllium oxide with the content of over 97 percent is obtained, and the recovery rate of the beryllium is about 80 percent. The method is suitable for extracting the beryllium oxide from low-grade beryllium ore with low BeO content and high CaF2 content.

The invention relates to a method for preparing LiNi1-xCoxO2 used as lithium-ion secondary battery anode material. It comprises following steps: dissolving nickel compounds and cobalt compounds into distilled water according to proportion; adding mixing solution of basic precipitant and oxidant and stirring strongly to make Co2+,Ni2+ deposite in form of Ni1-xCoxOOH; washing the deposition with distilled water and drying; mixing said deposition with lithium compounds, adding alcohol, water or mixture of that; grinding to make it be changed into flowing deformation phase pioneer matter; making lithium compound and Ni1-xCoxOOH mixed completely; drying said pioneer matter; and putting it into high temperature furnace, preheating, calcining, cooling and getting said LiNi1-xCoxO2. The invention is characterized by simple process, low cost, easy for industrial production, fine electrochemical property of got anode material and good circularity.

A composite additive for preparing hematite concentrate pellets comprises the following components: humic acid, calcium peroxide, and paigeite. During application, the composite additive is added which has a mass percent of 0.5%-1.6% of the total mass of the hematite concentrates, and the finished product pellets are obtained by pelletization, preheating, and roasting. Compared with pellets prepared by traditional technology, the hematite pellets prepared by the composite additive of the invention have improved falling strength of the green pellets, and compression strength of the finished product pellets; the preheating temperature and roasting temperature suitable for the pellets are reduced; both the preheating time and roasting time are shortened; the TFe grade is increased by 0.8%-1.2%. The composite additive of the invention has reasonable component ratios, is easy to process and manufacture, has a low using amount and a low residual amount, can significantly improve the pelletability of hematite concentrates which are difficult to be palletized, can improve the green pellet quality, has good heat stability, and can effectively reduce the preheating and roasting temperatures and shorten the preheating and roasting time of hematite concentrates. The composite additive of the invention is applicable to the production of oxidized pellets by hematites, and is especially applicable to the production of oxidized pellets by specularites. The composite additive of the invention is applicable to large-scale industrial production.

The invention discloses a rare-earth waste recovering and machining and treatment device system and a rare-earth waste recovering and machining and treatment method. Rare-earth waste is placed in a roasting furnace, and is subjected to oxidizing roasting on the condition of heat preservation after being heated to 850-1000 DEG C; rare-earth substances in the rare-earth waste are all turned into rare-earth oxide materials; an appropriate amount of water is added to a reactor and is heated to 200-250 DEG C; the measured materials and hydrochloric acid with the concentration being 0.8-1 mol/L areproportionally added to the reactor by several times for acidification decomposition; a rare-earth solution subjected to the acidification decomposition is supplied into the reactor for extraction andiron contained impurities are removed; then the rare-earth solution after iron is removed is supplied to an extraction tank for extraction; a praseodymium neodymium oxide solution is subjected to extraction separation and sedimentation; and sediments are fired. According to the rare-earth waste recovering and machining and treatment device system, through practical application measurement, the comprehensive recovery rate is above 97%, the purity of obtained (Pr and Nd) 203 is greater than or equal to 98%, the purity of Dy 203 is greater than or equal to 99%, and the recovering and machining cost for per ton of rare earth oxides is lower than 15,000 yuan.

The invention provides a method for extracting molybdenum and nickel and enriching precious metals from nickel and molybdenum ores. The method comprises the steps of (1) carrying out oxidized desulfurization and roasting; (2) smelting at high temperature to separate nickel and molybdenum: heating to 1250-1550 DEG C to enable the mixed furnace charge to be fused, and then, preserving the heat for 20-40min; (3) leaching and extracting the molybdenum for the first time; (4) leaching and extracting the molybdenum for the second time. The method provided by the invention is only used for removing sulfur in the nickel and molybdenum ores to be below 10%, so that the long roasting process is avoided, SO2 in the obtained smoke is high in concentration and can be directly used for preparing acids, meanwhile, the roasting time is greatly shortened, the production efficiency is remarkably increased, and the operation difficulty is lowered. The molybdenum can be converted into sodium molybdate and reserved in molten alkaline slag through adding sodium carbonate into the roasted clinker and melting the sodium carbonate under an alkaline condition, while the nickel is produced in an iced nickel or ferronickel way, so that the efficient separation of the nickel and the molybdenum is realized. The sodium carbonate is added in a melting process, so that the melting point and viscosity of the molten slag are reduced, and the iced nickel or ferronickel can be favorably settled and enriched.

The public invented a high-density lithium iron phosphate and a synthesis method thereof, the molecular expression formula of the high-density lithium iron phosphate is: Li1-x MexFe(PO4)1-1/3xFx (x is not less than or equal to 0.01 and not more than or equal to 0.10), wherein, Me is a cation doped element and is one of Li, Na and Mg. The synthesis method of the high-density lithium iron phosphate comprises the following steps: step 1: lithium salt, ferrous salt, phosphate and a fluxing agent are mixed according to the calculation of the molecular expression formula; step 2: required amount of reductive ferric iron is added, water or ethanol is taken as a dispersion medium, and granules are prepared by milling, drying and re-milling after the drying; step 3: the prepared granules are transferred into an atmosphere protection furnace and the black lithium iron phosphate is prepared after the calcination in the N2 gas environment. The lithium iron phosphate which is synthesized by using the method has the advantages of high specific capacity, high tap density, good cycle performance, good rate property, simple process and low cost, thereby being applicable to industrial mass production.

The invention discloses a method and a device for preparing a nickel iron roasted ore by utilizing a lateritic nickel ore. The method comprises the following steps: firstly, grinding the lateritic nickel ore into an ore powder, then carrying out high-temperature roasting of the obtained ore powder, during the high-temperature roasting process, allowing the ore powder to be in a pre-reduction system and carry out a high-temperature preheating reduction reaction, followed by allowing the high-temperature roasted ore to go into a rotary kiln for high-temperature calcination, thus obtaining a roasted ore containing nickel pig iron after completing high-temperature calcination, and then after dipping the roasted ore into water for cooling, separating to obtain the nickel iron roasted ore. The device comprises a hopper-type elevator, an air chute, a chute draught fan, a rotary feeder, a sluice valve, a rotary kiln, a water-cooling stirring tank, a burner, a hot wind mixing chamber, a high-temperature draught fan, a cyclone dust remover, a bag-type dust remover, a chain-type conveyor, a burner and a pre-reduction system. The preparation method and the device allow the heat transfer area of the ore powder to be large, enable each particle to be uniformly and fully subjected to a chemical reaction, have short reaction time, and have high utilization rate of the lateritic nickel ore.

The invention discloses a vanadium-doped in lanthanum site apatite-type lanthanum silicate solid electrolyte material and a preparation method thereof. The chemical formula of the solid electrolyte material is La10-xVx(SiO4)6O3+x; wherein, x is more than 0 and is not more than 1.5; the preparation method comprises the following steps: synthesizing apatite-type electrolyte material precursor through the sol-gel method with La(NO3)3-6H2O, tetraethoxy silane, glacial acetic acid and methanol in a molar ratio of 10-8.5:6:12:12, preparing membranes at 10-20MPa with the powder which is treated through drying and preroasting and finally roasting the membranes at 800-1500 DEG C for 2-6h. In the preparation method of the invention, the doping of vanadium in lanthanum site reduces the roasting temperature and time of the electrolyte material which has higher conductivity at the middle-low temperature(600-800 DEG C) and is used for the electrolyte layer of the solid oxide fuel cell so that the service life of cells can be effectively prolonged.

The invention discloses a method for performing microwave arsenic removal on high-arsenic iron ore and belongs to the technical field of mineral separation. The method comprises the following steps: crushing the high-arsenic iron ore until the granularity is less than 1mm, adding a proper amount of pulverized coal, uniformly mixing, performing microwave roasting in an industrial microwave oven, controlling the temperature at 800-1200 DEG C, wherein the roasting time is 5-30 minutes, the arsenic is separated from the iron ore in a gas state form, low-arsenic iron ore concentrate which meets the industrial requirements is obtained, and the generated arsenic-containing tail gas is recycled by virtue of a flue gas absorption device arranged on the industrial microwave oven. According to the method, effective separation between the arsenic and the iron ore is promoted by utilizing selective heating of microwave on the iron ore, the arsenic removal rate is over 90 percent, and the method is a high-efficiency low-cost method for removing arsenic from the iron ore.

The invention discloses a stone coal vanadium ore oxidizing, crystal breaking, roasting and vanadium extracting comprehensive utilization system. A crusher, a high-pressure roller mill, a first feeding belt, a feeding bin, a second feeding belt and a spiral feeder are sequentially matched with one another, and the discharging end of the spiral feeder is matched with a feeding port of a suspensiondecarburization roasting furnace; the suspension decarburization roasting furnace, a first cyclone separator, a suspension crystal breaking roasting furnace, a second cyclone separator and a cooler are sequentially communicated in series; a combustor and an air inlet are respectively arranged at the bottoms of the suspension decarburization roasting furnace and the suspension crystal breaking roasting furnace; an air inlet of the cooler is communicated with an air compressor; and a discharging hole in the bottom of the cooler is matched with a feeding hole of an acid mixing curing furnace; andthe acid mixing curing furnace, a first leaching tank, a first filtering device, a second leaching tank, a second filtering device, a pH value adjusting tank and a third filtering device are sequentially connected in series and matched with one another. The system provided by the invention is stable in operation, large in treatment capacity, low in energy consumption and cost of unit treatment capacity, and capable of easily controlling product properties and easily achieving large-scale equipment.

The invention provides a preparation method for a doped and modified spinel-type lithium manganite cathode material, which comprises the following steps of: mixing a lithium source compound, a manganese source compound, doped metal salt with a roasting accelerator to obtain a mixture; then, roasting the mixture to obtain metal element-doped spinel-type lithium manganite, wherein the roasting accelerator comprises one or more than one of acetylene black, active carbon powder, coke powder and charcoal powder. The preparation method provided by the invention is low in roasting temperature and is short in roasting time, and meanwhile, the obtained doped and modified spinel-type lithium manganite is stable in product quality and is uniform in performance.

The invention provides a lithium ion battery anode material with LiCoO2 coated on the surface and a preparation method for the lithium ion battery anode material. The preparation method comprises the following steps of: uniformly mixing an anode material, a low-melting-point salt, a lithium compound and a cobalt compound; raising the temperature to be between the melting point and the boiling point of the low-melting-point salt to form a molten salt medium; reacting for a certain period of time, and then cooling to the room temperature; and washing and drying to obtain the lithium ion battery anode material with the LiCoO2 coated on the surface. By the preparation method, the molten salt is used as a reaction medium, the process is simple, the synthesis temperature is low, the holding time is short, a layer of electrochemical active substance is formed on the surface of base material particles, the performance and the structure of the base material of the anode material are not changed, and advantages of a modified layer is obtained.

The invention provides a pressurization roasting method for carbon, and relates to a carbon roasting process. The pressurization roasting method for the carbon can avoid shell wastes, reduce the crack wastes caused by temperature difference and shorten the roasting time. The method comprises the following steps of: placing a compression green body product in a saggar, and filling a filler betweenthe product and the saggar; and after the product is filled in the saggar, sealing and vacuumizing, inflating nitrogen, placing in a roasting furnace, and heating, wherein the pressure is kept 2.5 to1.5 MPa, and when the pressure exceeds an upper limit, the pressure can be released through a valve and the valve is closed when the pressure is close to the lower limit. By using the anaerobic state, the shell wastes are avoided. By using the saggar, the periphery of the product is heated uniformly, the temperature difference among positions of the product can be reduced and the crack wastes caused by the temperature difference are reduced. An 804-hour roasting curve is performed for roasting and the roasting time can be reduced by about 12 percent. Through experiment, under the same condition, compared with the conventional carbon roasting method, the pressurization roasting method can obviously improve the product yield, coking rate, volume density and recovery yield.

The invention discloses a stone coal vanadium ore oxidation grain breaking roasting comprehensive utilization method. The method is carried out according to the following steps (1) a stone coal vanadium ore is crushed and ground to obtain powder ore; (2) the power is delivered to a suspended decarburization roasting furnace for decarburization reaction; (3) a decarburized material is subjected tocyclone separation and then enters a suspended grain breaking roasting furnace to be subjected to a grain breaking oxidation reaction; (4) an oxidized material is discharged after cyclone separation;(5) cooling is conducted to 150-200 DEG C is conducted, acid mixing curing leaching, or directly leaching is conducted; (6) a leached material is filtered to obtain a V2O5 leaching solution; (7) filter residue is mixed with a sodium hydroxide solution for secondary leaching, and filtering is conducted to obtain a secondary filtrate; (8) hydrochloric acid is added into the secondary filtrate to generate white precipitate, and filtering is conducted to obtain third filter residue, and drying is conducted to obtain white carbon black. According to the method, sodium salt adding is not required byroasting, the problems of incomplete vanadium oxidation, low equipment processing amount, high operation cost and the like in a traditional process are solved, the process flow is simple, equipment and system operation are stable, and energy consumption and cost for unit processing amount are low.