207results about How to "Reduce silicon content" patented technology

The invention discloses a method for producing superfine aluminium hydroxide and aluminium oxide by taking flyash of a recirculating fluidized bed as a raw material. The method comprises the following steps of: a) grinding the flyash, performing wet magnetic separation and deironization, and reacting with hydrochloric acid to obtain hydrochloric acid extract; b) introducing the hydrochloric acid extract into a macroporous cationic resin column for adsorption, after adsorptive saturation of the resin, eluting by using an eluant to obtain eluent containing aluminium chloride and iron chloride; c) removing iron from the eluent by using alkaline solution to obtain solution of sodium metaaluminate; d) adding a dispersing agent into the solution of sodium metaaluminate, and mixing uniformly to obtain dispersion; and e) performing carbon decomposition on the dispersion to obtain the superfine aluminium hydroxide. The superfine aluminium hydroxide is calcined at different temperatures to form gamma-aluminium oxide and alpha-aluminium oxide respectively. Compared with other methods, the method has the advantages of wide sources of raw materials, simple production process and high purity of the products.

A hot-rolled austenitic manganese steel strip having a chemical composition in percent by weight of 0.4%≦C≦1.2%, 12.0%≦Mn≦25.0%, P≧0.01% and Al≦0.05% has a product of elongation at break in % and tensile strength in MPa of above 65,000 MPa %, in particular above 70,000 MPa %. A cold-rolled austenitic manganese steel strip having the same chemical composition achieves a product of elongation at break in % and tensile strength in MPa of above 75,000 MPa %, in particular above 80,000 MPa %.

A photomask blank has a light-shielding film composed of a single layer of a material containing a transition metal, silicon and nitrogen or a plurality of layers that include at least one layer made of a material containing a transition metal, silicon and nitrogen, and has one or more chrome-based material film. The high transition metal content ensures electrical conductivity, preventing charge-up in the photomask production process, and also provides sufficient chemical stability to cleaning in photomask production. The light-shielding film has a good resistance to dry etching of the chrome-based material film in the presence of chlorine and oxygen, thus ensuring a high processing accuracy.

The invention relates to a method for preparing cryolite by alkaline leachate of a cathode carbon block of an aluminum electrolytic cell, and belongs to a leachate preparation method. The method comprises the steps of grinding the cathode carbon block of the aluminum electrolytic cell to a certain particle size, mixing the ground cathode carbon block with alkaline liquid, carrying out size mixing, carrying out stirring leaching at a heating temperature of 20-90 DEG C, filtering to obtain first filtrate and a first filter residue, adding sodium fluoride and a small amount of Na3AlF6 solids into the first filtrate, controlling the introducing velocity of CO2-rich gas to generate precipitates while heating and stirring, after the reaction is finished, filtering to obtain second filtrate and a second filter residue, and drying the second filter residue at 100-150 DEG C, so as to obtain a cryolite product. According to the method, acidy leaching is replaced with alkaline leaching, so that the equipment requirements in the production process are reduced, processing processes such as flotation are omitted, an absorption process of hydrogen fluoride is omitted, and the processing process is simplified; a high-temperature processing process is saved, so that the energy consumption is reduced; and by adding crystal seeds, high-quality cryolite with the uniform particle size is generated when airflow rate is controlled. The method has the beneficial effects that the process is simple, a closed loop is utilized, the resource utilization rate is high, and the secondary pollution is avoided.

The invention discloses an iron-increasing and silicon-reducing reselection technique for mixed-type lean iron ore tailings, comprising the following steps of: strong magnetic roughing: putting mixed-type lean iron ore tailings through a strong magnetic separator with the magnetic field intensity of [U1] Oersteds to obtain roughed concentrate and roughed tailings; strong magnetic cleaning: selecting the roughed concentrate in the strong magnetic separator with the magnetic field intensity of 10000-20000 Oersteds to obtain magnetic concentrate and magnetic tailings; centrifugal selecting: putting the magnetic concentrate in a centrifugal concentrating machine with the rotating speed of 150-250r/min to obtain centrifugal concentrate and centrifugal tailings; and table selecting: selecting the centrifugal tailings through a table with the stroke of 8-10mm and the frequency of stroke of 250-300 times/min to obtain table concentrate and table tailings. According to the iron-increasing and silicon-reducing reselection technique, a great quantity of tailings is dropped through rough and concentrate double magnetic selection; the magnetic concentrate is selected by using the centrifugal machine so that irons are increased and silicon is reduced; and then the centrifugal tailings are selected by using the table so that the productivity is increased. The iron-increasing and silicon-reducing reselection technique has the effects of realizing iron increment and silicon reduction of the mixed-type lean iron ore tailings, incrasing the productivity of the iron ore to a great extent at the same time and providing an effective approach to iron increment and silicon reduction of the reselected concentrate for the mixed-type lean iron ore tailings.

The invention relates to a steel and a production technique thereof, in particular to a non-carbide bainite wear-resistant steel plate and a production technique thereof; the component weight percentages are: 0.15 to 0.25 percent of C, 1.50 to 2.00 percent of Mn, 0 to 0.015 percent of P, 0 to 0.006 percent of S, 1.30 to 2.00 percent of Si, 0.20 to 0.60 percent of Al, 0.60 to 1.00 percent of Cr, 0.25 to 0.50 percent of Mo, 0.010 to 0.035 percent of Nb and the rest is Fe. The production technique is carried out according to the following working procedures: (1) feeding a continuous casting plate to a heating furnace for heating; (2) feeding the continuous casting plate after being heated into a hot rolling production line to carry out the rolling of controlled rolling and controlled cooling; (3) carrying out middle-low temperature drawing temper on a rolling steel plate after the rolling is finished. The non-carbide bainite wear-resistant steel plate can be produced by the working procedures without carrying out online or offline hardening and tempering thermal processing which not only can simplify the working procedures of production, but also can improve the performance and the quality of a product as well as obtain the bainite wear-resistant steel with high intensity and high toughness.

The invention relates to a skin tightening composition and application thereof. The skin tightening composition is prepared from the following ingredients: skin restoration compositions, low-molecular-weight hyaluronic acid silanol, skin tightening compositions, carnosine, anti-wrinkle peptide composition, conopeptide, anti-wrinkle compositions and plant extract compositions. The skin tightening composition has the advantages that the obvious advantages are realized in the aspects of timely improving the skin compactness and resisting fatigue; after the skin tightening composition sample is smeared for 30min, the skin elasticity can be improved by 3.3 to 4.34 percent; the skin fatigue resistant degree is reduced by 17.95 percent to 20.33 percent.

Te invention discloses a production technological method for reducing oxide block masses (pellets) containing carbon, iron and/or zinc, etc. into molten iron and/or zinc, etc. in a blast furnace molten iron trough (containing a swing flow spout in front of a furnace) and belongs to the field of steel metallurgy. The production technological method is characterized in that the oxide block masses containing the carbon, iron and/or zinc, etc. are added into the blast furnace molten iron trough before blast-furnace tapping and/or during tapping, so that the iron and/or zinc, etc. in the block masses are obtained in a reduction mode through the carbon. The production technological method has the advantages that one kind or several kinds of industrial powder material of cheap blast furnace gas dust (or gas mud), gravitational dust collection dust, sintering machine dust collection dust, converter dust collection dust (or mud), steelmaking steel slag powder, oxidized iron scales, reduced iron powder, etc. and reductants of carbon-containing coal powder, coke powder, etc. are mixed and made into the block masses, the block masses are added into the blast furnace molten iron trough, and the zinc is recovered through increased iron and/or dezincification; the industrial powder material difficult to treat is treated well, so that good economic and social benefits are achieved. Meanwhile, the effect of molten iron desilicication is further achieved.

The invention relates to ultralow-temperature welded alloy steel and the production method thereof. The production method sequentially comprises the following working procedures of: 1) smelting; 2) electroslag remelting; 3) forging; 4) steel rolling; and 5) drawing. The low-temperature impact performance of the ultralow-temperature welded alloy steel is similar to that of the austenitic stainless steel, and even under the welding state, the ultralow-temperature welded alloy steel still has enough high impact property at subzero 196 DEG C as well as good mechanical property and corrosion resistance in various corrosion media.

The invention relates to a method for preparing low-grade non-oriented electrical steel processed by rare earth and belongs to the field of electrical sheet. The low-grade non-oriented electrical steel with excellent magnetic properties is finally obtained by using short-process continuously cast blooms as raw materials through the steps of hot rolling, cold rolling and annealing. The design requirement of 0.001 to 0.005 percent of C, 0.5 to 1.0 percent of Si, 0.25 to 0.50 percent of Mn, less than or equal to 0.080 percent of P, less than or equal to 0.005 percent of S, 0.25 to 0.50 percent of Al, 0.0014 to 0.020 percent of RE (Ce) and the balances of iron and unavoidable impurities on ingredients of the hot rolling raw materials is met. The product has the final magnetic properties that when the thickness of a steel plate is 5mm, P15/50 is in the range of 3.45 to 5.02W/Kg and B5000 is in the range of 1.67 to 1.75T. The low-grade non-oriented electrical steel processed by the rare earth has the advantages that compared with the prior art, the low-grade non-oriented electrical steel has low silicon content and low O content and N content and excellent magnetic properties; and the production cost is reduced.

A method for preventing the formation of watermark defects includes the steps of forming a pad oxide, a silicon nitride layer and a silicon oxynitride layer over a semiconductor substrate. A photoresist mask is formed over the resulting structure, with the silicon oxynitride layer being used as an anti-reflective coating during exposure of the photoresist material. An etch is performed through the photoresist mask, thereby forming a trench in the substrate. The photoresist mask is stripped, and the silicon oxynitride layer is conditioned. For example, the silicon oxynitride layer may be conditioned by a rapid thermal anneal in the presence of oxygen or nitrogen. A wet clean step is subsequently performed to remove a native oxide layer in the trench. The conditioned silicon oxynitride layer prevents the formation of watermarks during the wet clean process.

The invention discloses a clean process method for efficiently extracting chromium in extracted vanadium tailings. For the extracted vanadium tailings, a silicon fixing agent is added while silicon is leached with low-concentration sodium hydroxide; the silicon is converted into an inert compound in the alkaline leaching and chromium extracting process; the inert compound is subjected to alkaline leaching and chromium extracting to obtain sodium chromate alkali solution with lower silicon content and iron-enriched tailings, so that high-efficiency extraction of the chromium in the extracted vanadium tailings and comprehensive utilization of valuable components are realized. According to the clean process method disclosed by the invention, the high-efficiency extraction of the chromium in the extracted vanadium tailings can be realized, the extraction rate of the chromium is larger than 85 percent, and the content of the silicon in the obtained sodium chromate alkali solution is lower.

The invention provides high-silicon nitrogen-contained austenitic stainless steel. The high-silicon nitrogen-contained austenitic stainless steel is characterized by comprising chemical compositions including, by mass percent, 15%-20% of Cr, 15%-20% of Ni, 2%-5% of Mn, 4.5%-6.0% of Si, 1%-3% of Mo, 0.5%-1.5% of Cu, 0.1%-0.3% of N, not larger than 1.0% of Al, 0.05%-0.5% of RE, not larger than 0.03% of C, not larger than 0.010% of S, not larger than 0.02% of P and the balance Fe. The invention further provides a preparing method of the above high-silicon nitrogen-contained austenitic stainless steel. The high-silicon nitrogen-contained austenitic stainless steel is mainly used for in the field of chemical engineering, in particular to the sulfuric acid industry; the high-silicon nitrogen-contained austenitic stainless steel can be further used in the fields of food catering instruments, ornaments, environmental protection and the like; and according to the high-silicon nitrogen-contained austenitic stainless steel, by optimizing the silicon content and adding the nitrogen, the copper, the aluminum and the rare earth elements, the corrosion resistance of the stainless steel is improved, and the stainless steel has the excellent cold and heat machining performance and corrosion resistance.

The invention relates to a delay coking defoaming agent composition and a preparation method thereof, the defoaming agent is prepared by compounding fluorine-containing polysiloxane, glycerin type dendritic polyether, high carbon alcohol and a solvent. The preparation method of the defoaming agent is as follows: dispersing the fluorine-containing polysiloxane in the high carbon alcohol, stirring for 1 to 2 hours at 10-30 DEG C, then adding the glycerin type dendritic polyether and the solvent, stirring for 1 to 5 hours at 100-150 DEG C, and cooling to obtain a defoaming agent product. The delay coking defoaming agent has excellent defoaming antifoaming performances at 400-500 DEG C, in a high temperature delay coking process, the delay coking defoaming agent can still maintain good defoaming antifoaming performances and stability.

The invention discloses an automatic preparation method of a SiCf/SiC composite material flame tube. The preparation method comprises the following steps: preparing an interface layer from SiC fibersby adopting chemical vapor deposition, so as to obtain SiC fibers with a continuous interface layer; performing unidirectional tape laying and filament winding on the SiC fibers with the continuous interface layer according to the fiber volume and fiber orientation obtained by simulation calculation, so as to obtain net size forming preform; performing densifying treatment on the obtained preformby adopting a reactive melt infiltration process and the chemical vapor deposition process; preparing an environmental barrier coating on the surface of the obtained preform; finally, continuously preparing a thermal barrier coating on the surface, thereby fully intelligently obtaining the high-density SiCf/SiC composite material flame tube. The SiCf/SiC composite material flame tube prepared withthe method disclosed by the invention has the characteristics of high temperature resistance and long service life and also has the advantages such as low thermal expansion coefficient, high thermalconductivity, high thermal shock resistance and excellent mechanical property. Meanwhile, the preparation method is high in degree of automation, short in production cycle, low in cost and controllable in quality.

The invention relates to a coal gangue ceramsite proppant and a preparation method thereof. The proppant comprises, by weight, 30%-70% of coal gangue, 20%-65% of flint clay, 5%-10% of a sintering aidand 1-3% of a forming agent. The coal gangue is solid wastes which are discharged in coal collecting process and coal washing process, the silica content is higher, the aluminum content is lower, thecalorific value of the solid waste coal gangue is fully utilized in the preparation process, meta components of the coal gangue are completely utilized again to reduce the volume density of sintered ceramsite to better adapt to the technical demands of oil well fracturing construction, fracturing cost is reduced, and the use of high-grade bauxite resources is reduced to help to protect the environment.

The invention provides a low Si-Mg ratio and low RE-Mg nodularizer. The nodularizer comprises the following components by mass percent: 5 to 10 percent of Mg, 20 to 30 percent of Si, 0 to 2 percent of Ca, 0 to 0.5 percent of Al, 0 to 0.2 percent of Bi, 0 to 0.1 percent of Ba, 0 to 0.1 percent of Zr, less than 0.1 percent of Ce, less than 0.1 percent of La and Fe in balancing amount. The nodularizer provided by the invention has the advantages that the Si content and the RE content in the nodularizer are considerably reduced on the premise that smooth iron liquid nodulizing is guaranteed, so that not only the range of control of the Si content of original iron liquid is widened, but also beneficial technological conditions are created for enhancing modification, and the carbonide of thin-walled parts and the fragmental graphite of thick-walled parts can also be effectively eliminated; the nodulizing effect is excellent; and the nodularizer is especially suitable for production of high-quality high-ductility ductile iron castings and high-Ni austenite ductile iron castings.

A pretreatment leaching process of flotation zinc oxide concentrates includes the following steps that a small amount of concentrated sulfuric acid is added into the flotation zinc oxide concentrates and stirred evenly; heat-preservation curing is carried out on obtained mineral powder at a low temperature to partially decompose flotation chemicals on the surface of the flotation zinc oxide concentrates; the obtained clinkers are leached out with waste electrolytes, filtered and separated; and finally, a small amount of active carbon is added into the zinc sulfate solution obtained after filtering and separation for adsorption, filtering and separation are carried out again, and zinc oxide concentrate leachate is obtained. The pretreatment leaching process of flotation zinc oxide concentrates has the advantages of being simple, environmentally friendly and the like, can optimize the leaching conditions of the concentrates, and resolves the problems of residual floatation chemicals and the like.

The invention relates to a method for reducing the silicon content in a green liquid of a non-wood fiber material pulping causticization section through the cooperation of calcium oxide and aluminum salt. In the method, calcium oxide and aluminum sulfate, aluminum oxide, aluminum hydroxide or sodium metaaluminate are sequentially added into the green liquid of the causticization section, the temperature is 90-100 DEG C in the reaction process, a stirrer is used for continuous stirring in the reaction process, the reaction time is 25-30 minutes, and insoluble precipitate is removed by filtration after the reaction is completed. The method is provided for the green liquid produced during non-wood fiber material pulping, and comprises the following steps: adding calcium oxide and aluminum salt into the green liquid of the pulping causticization section to react with silicate in the green liquid so as to generate insoluble precipitate, then filtering to remove the generated insoluble precipitate from the green liquid. The method can achieve a silicon removal rate higher than 87%, and ensures that white slime can be used for calcining and recycling lime after causticization.