676 results about "Dolomite" patented technology

The invention provides a mineralization composition as well as a preparation method and application thereof. The mineralization composition comprises modified celestite, modified strontium-containing dolomite, modified medical stone, modified zeolite, modified tourmaline, modified wollastonite and modified serpentine. The strontium ion dissolution amount of the modified celestite is 50 to 55 mg / L; the strontium ion dissolution amount of the modified strontium-containing dolomite is 15 to 20 mg / L; the metasilicate ion dissolution amount of the modified medical stone is 30 to 35 mg / L; the metasilicate ion dissolution amount of the modified zeolite is 40 to 45 mg / L; the metasilicate ion dissolution amount of the modified tourmaline is 3 to 5 mg / L; the dissolution amount of metasilicate ions in the modified wollastonite is 3 to 5 mg / L; the dissolution amount of metasilicate ions in the modified serpentine is 10 to 15 mg / L. The mineralization composition can stably and enduringly release strontium ions and metasilicate ions, and also can adjust the water quality to alkalescence, so that the water quality reaches the national drinking water standard, and safe and healthy drinking water can be provided for users.

The invention belongs to the technical field of glass, and particularly relates to high-light-transmittance glass and a preparation method of the high-light-transmittance glass. The raw materials comprise the following components in parts by weight: 20 to 30 parts of quartz sand, 15 to 18 parts of sodium carbonate, 8 to 10 parts of limestone, 5 to 7 parts of dolomite, 0.3 to 0.5 part of a clarifying agent, 0.2 to 0.3 part of a coloring inhibitor, 0.1 to 0.2 part of lithium carbonate, 0.05 to 0.1 part of titanium dioxide, 0.1 to 0.3 part of zirconium oxide, 2 to 4 parts of aluminum oxide, 1 to 3 parts of boron oxide, 0.3 to 0.5 part of nano silicon dioxide sol and 1 to 3 parts of a high-temperature-resistant agent; and 1-5 parts of a wear-resistant agent. The quartz sand, the sodium carbonate, the limestone, the dolomite, the clarifying agent, the coloring inhibitor, the lithium carbonate, the titanium dioxide, the zirconium oxide, the aluminum oxide, the boric oxide, the nano silicon dioxide sol, the high-temperature-resistant agent and the wear-resistant agent are used as raw materials, so that the prepared glass is high in light transmittance, and meanwhile, the performance requirements of high strength, low spontaneous explosion rate and the like are met.

The invention discloses double-layer fancy glaze with chapped ground texture and a preparation method of the double-layer fancy glaze, and relates to the technical field of ceramic glaze. The double-layer fancy glaze is composed of a ground glaze layer and a cover glaze layer. The ground glaze raw materials comprise potassium feldspar, kaolin, calcite, quartz, dolomite, zinc oxide and pigment; the cover glaze raw materials comprise potassium feldspar, waste porcelain powder, blank powder, chinastone, limestone, sepiolite, quartz, zirconium silicate with the particle size D50 being less than or equal to 1.0 mu m and pigment. The preparation method comprises the following steps: respectively carrying out ball milling to prepare ground glaze slip (32-40 baume degrees) and cover glaze slip (51-53 baume degrees); spraying ground glaze on the green body, drying, and then soaking with cover glaze; and finally, sintering at the temperature of 1250-1270 DEG C in a reducing atmosphere. Through the synergistic effect of the sepiolite and other components, the cover glaze has high surface tension, forms a microcrack network during drying, generates controllable glaze shrinkage during firing, forms a three-dimensional chap texture with crack width of 1-5mm and strong curled and raised crack edges, and meanwhile, the ground glaze completely covers a green body, so that the product practicability is ensured.

The invention belongs to the technical field of water treatment agents, and particularly relates to a water treatment agent based on comprehensive utilization of red mud and a preparation method thereof. The water treatment agent based on comprehensive utilization of red mud is prepared from the following preparation raw materials in parts by weight: 95 to 105 parts of red mud, 25 to 35 parts of dolomite, 10 to 20 parts of diatomite and 5 to 10 parts of sodium polyacrylate. The invention aims to break through the technical bottleneck of a red mud-based water treatment agent through component design and process optimization. The adsorption activity of red mud is activated by introducing dolomite to regulate the alkalinity of a system, mass transfer and dispersity are enhanced by utilizing the high specific surface area of diatomite, and rapid flocculation separation of adsorbed pollutants is realized by virtue of assistance of sodium polyacrylate. All the components form a synergistic removal mechanism aiming at COD, ammonia nitrogen and total phosphorus through pH regulation and control, multi-level adsorption, coprecipitation and flocculation coupling effects, the treatment efficiency and economical efficiency are remarkably improved, and a new way is provided for high-value utilization of the red mud.

The present invention provides a glass sheet having soda-lime-silica glass composition with a high visible light transmittance (LtC) of at least 89% with a dominant wavelength (DW) from about 490 to 505 nanometers and purity (Pe) of no more than 1% for control thickness of 5.66 mm and methods of making the same. The glass composition comprising a low iron raw material, a total iron oxide (Fe2O3) of 0.02 to 0.06 wt. %, ferrous (FeO) from 0.006 to 0.02 wt. %, redox (FeO / Fe2O3) from about 0.30 to 0.55, Cr2O3 from about 0.3 to 10 ppm, TiO2 from about 50 to 500 ppm, SnO2 from about 10 to 500 ppm, and a critical amount from about 0.10 to 0.25 wt. % of SO3. The low content of iron oxide is achieved by the partial substitution of regular raw materials by low iron raw materials, with a complete substitution of regular dolomite by a low iron dolomite with a maximum content of 0.020 wt. % Fe2O3.

The invention belongs to the technical field of ceramics, and particularly relates to a three-dimensional effect glaze, a three-dimensional effect ceramic tile and a preparation method thereof. The three-dimensional effect glaze is composed of honeycomb ground glaze and honeycomb effect glaze; the honeycomb ground glaze comprises the following mineral components in percentage by mass: 20%-30% of quartz, 5%-10% of kaolin, 12%-18% of albite, 7%-15% of calcite, 2%-7% of wollastonite, 12%-17% of calcined talc, 15%-25% of calcined zinc oxide, 2%-6% of titanium dioxide, 2%-4% of glass powder, 1%-3% of strontium carbonate and 1%-5% of dolomite. The glaze with the honeycomb effect comprises the following mineral components in percentage by mass: 5%-15% of quartz, 5%-10% of kaolin, 40%-55% of albite, 2%-6% of barium ice feldspar, 2%-10% of calcite, 7%-15% of calcined talc, 1%-4% of calcined zinc oxide, 7%-15% of red mud and 3%-5% of coal gangue. The novel effect glaze is developed, the glaze surface is flat and smooth, meanwhile, the ground glaze is pushed to the surface through the gas phase disturbance effect, and the effect glaze sinks and wraps the ground glaze in a three-dimensional honeycomb shape.

The utility model relates to the technical field of artificial diamond superhard materials, and discloses a synthetic block device filled with high-density materials in multiple directions, which comprises two outer frames formed by pyrophyllite, a filling groove is arranged on the plane of each outer frame, a filling layer is filled in each filling groove, and the outer frames are filled with high-density materials. Wherein the filling layers in at least one group of symmetrical filling grooves are conductive; a dolomite lining is arranged in the outer frame; according to the utility model, under the precondition of meeting stable growth of crystals, the pressure can be reduced by 8-15 Mpa on the basis of the original pressure, the service life of the cubic press can be directly prolonged, the frequency of beam disassembly and maintenance is reduced, the cost of manpower and material resources is saved, and favorable conditions are provided for enterprises to realize cost reduction and efficiency improvement.

The invention relates to the technical field of mineralized filter elements, particularly provides a magnesium-containing mineralized filter material, a mineralized filter element and a preparation method of the mineralized filter element, and aims at solving the problem that the service life of the magnesium mineralized filter element is shortened due to the fact that the magnesium ion release speed of the existing magnesium mineralized filter element is too high. The magnesium-containing mineralized filter material comprises modified magnesium ore and modified dolomite, wherein the mass ratio of the modified magnesium ore to the modified dolomite is (0.25-6): 1. By controlling the ratio of the modified magnesium ore to the modified dolomite, the precipitation concentration and speed of magnesium ions in water can be controlled, so that the concentration of the magnesium ions in the water can meet user requirements, and the service life of a magnesium mineralization filter element can be prolonged.

A salt-cavern gas storage roof dolomite creep damage prediction method relates to the technical field of rock mechanics and comprises the following steps: acquiring elastic mechanical parameters and geological parameters of salt-cavern gas storage roof dolomite, and establishing a rock creep damage model under the action of graded circulation gas injection load; obtaining a rock creep rate control model under the action of the staged cycle gas injection load, performing parameter identification on the rock creep rate control model, and predicting the creep damage state of the dolomite of the reservoir roof under the action of the staged cycle gas injection load by using the rock creep rate control model subjected to parameter identification in combination with the elastic mechanical parameters and the geological parameters; according to the method, the creep mechanical behavior of the dolomite of the top plate of the salt-cavern gas storage under the action of the high-frequency cyclic load can be accurately represented, the creep time threshold value of the top plate can be accurately predicted, and the influence rule of the graded load on damage accumulation is quantified; therefore, an accurate quantitative decision basis is provided for gas injection load regulation and control and safe operation cycle optimization of the salt-cavern gas storage.

The invention discloses a magnetic separation-flotation combined stepped deep iron removal method for granite tailings. According to the method, after granite tailings are subjected to ore grinding treatment, magnetic separation impurity removal, black and white mica ore removal through reverse flotation and fine ferrodolomite ore removal through reverse flotation are conducted in sequence, after the pH of reverse flotation tailings is adjusted, fluoride-free and acid-free separation is conducted, low-iron quartz concentrate and feldspar rough concentrate are obtained, the feldspar rough concentrate is subjected to regrinding and secondary magnetic separation impurity removal, and the low-iron quartz concentrate and the feldspar rough concentrate are obtained. And low-iron feldspar concentrate is obtained. According to the method, no strong acid is involved in the whole process, the technical problem that in the prior art, strong acid is introduced in quartz and feldspar flotation, and consequently waste water and waste liquid pollution is caused is fundamentally solved, and efficient and deep removal of iron impurities in the granite tailings is achieved through the magnetic separation pre-enrichment-three-section flotation separation-step deep iron removal technology. And the overall removal efficiency of the iron impurities is remarkably improved, and comprehensive utilization of granite tailings resources is achieved.

The invention relates to the technical field of fracturing propping agents, in particular to a method for preparing a ceramsite sand fracturing propping agent by taking asbestos ore as a raw material. The ceramsite sand fracturing propping agent comprises inner core particles and an outer layer covering film, wherein the inner core particles comprise the following components in parts by weight: 25-35 parts of asbestos ore, 40-50 parts of bauxite, 10-20 parts of solid waste ceramsite sand, 1-3 parts of a sintering aid, 15-25 parts of potassium feldspar, 3-8 parts of dolomite, 8-12 parts of kaolin, 1-2 parts of titanium oxide and 0.5-1.5 parts of manganese powder; and the outer-layer covering film is modified epoxy resin. The ceramsite sand fracturing propping agent prepared by the invention not only has excellent mechanical property and high flow conductivity, but also has excellent hydrophobic property, so that the service life of the ceramsite sand fracturing propping agent is prolonged.

The invention discloses a method for promoting phytoremediation of heavy metal contaminated soil by combining modified charcoal with microorganisms, and relates to the technical field of heavy metal contaminated soil remediation. The repairing agent is prepared and comprises an inner layer, a middle layer and an outer layer, envelopes are arranged among the layers, the outer layer is further coated with an outer envelope, the inner layer comprises modified biochar and a first microbial agent, the middle layer comprises modified biochar and a second microbial agent, and the outer layer comprises dolomite powder and oyster shell powder. According to the invention, the remediation agent is combined with the heavy metal enrichment plants to carry out synergistic remediation on the contaminated soil, so that the enrichment plants can grow well under the high-acid high-concentration heavy metal environment condition, the problem of low biomass of the enrichment plants is solved, and finally, the efficient remediation of the contaminated soil is realized.

The invention relates to the technical field of agricultural fertilizers, in particular to an organic-inorganic composite silicon-calcium-magnesium fertilizer and a preparation method and application of the organic-inorganic composite silicon-calcium-magnesium fertilizer. The high-temperature activated silicon-calcium-magnesium mineral powder is composed of calcined wollastonite powder, calcined serpentine powder, dolomite powder and zeolite powder; 2%-5% of an organosilane modifier, wherein the organosilane modifier is composed of gamma-aminopropyl triethoxy silane and gamma-glycidyl ether oxypropyl trimethoxy silane, and the organic silane modifier is composed of gamma-aminopropyl triethoxy silane and gamma-glycidyl ether oxypropyl trimethoxy silane; 18%-35% of a functional organic matter complex, wherein the functional organic matter complex is composed of mineral source sodium humate, bioactive small peptide, sodium alginate and polyglutamic acid; and 3%-8% of auxiliary functional components, so that the solubility and the bioavailability of silicon, calcium and magnesium elements in minerals are remarkably improved.

The invention discloses an organic-inorganic compound conditioner for acidic purple soil as well as preparation and application of the organic-inorganic compound conditioner. The organic-inorganic compound conditioner is prepared by compounding an inorganic material dolomite powder or yellow phosphorus slag and an organic material pepper branch organic fertilizer (obtained by fermenting pepper branches), the raw materials are all industrial and agricultural wastes and are rich in local resources in Chongqing, the problem of how to recycle the wastes is solved, and the cost of the conditioner is also reduced. When the organic-inorganic compound conditioner is applied to acid purple soil according to the inorganic-organic weight ratio of 1: 2, 150 kg / mu of organic fertilizer and 75 kg / mu of inorganic material, the interaction effect of the organic fertilizer and the inorganic material is obvious, soil structure adjustment and crop growth are remarkably improved, maximum utilization of resources is achieved, and the conditioner is environmentally friendly, saves energy and has wide application value and prospects.

The invention discloses an environment-friendly tundish magnesium-calcium dry material for thin-strip cast-rolling short-process steelmaking, and belongs to the technical field of refractory materials. The invention discloses an environment-friendly tundish magnesium-calcium dry material for thin-strip cast-rolling short-process steelmaking. The tundish magnesium-calcium dry material is prepared from the following raw materials in percentage by mass: 44-62.5% of magnesia aggregate, 22.5-24% of dolomite aggregate, 11-28% of magnesia fine powder and 3-5% of a binding agent, the binding agent is silica sol modified by a phosphate esterification aluminic acid ester coupling agent. The preparation method comprises the following specific steps: putting magnesia fine powder, a binding agent, magnesia aggregate and dolomite aggregate into a V-shaped mixing mill, uniformly stirring for 5 minutes, putting the stirred mixture into a mold, ramming, vibrating and molding to obtain a molded green body, curing at room temperature for 24 hours, demolding, drying at 200 DEG C for 24 hours, and carrying out heat treatment in an air atmosphere to obtain a dry material sample. According to the invention, the binding agent with good compatibility with a matrix is prepared by improving the binding agent, so that the binding agent can play a reinforcing role.

The invention relates to a preparation method of a multi-layer composite pellet and the pellet. The preparation method comprises the following steps: mixing hematite powder, pellet return ore powder, boric sludge powder and dolomite powder to prepare pretreated hematite powder; uniformly mixing magnetite powder and bentonite to obtain a mixture; pelletizing the mixed material; spraying atomized water and conveying the pretreated hematite powder into the pelletizer to prepare green pellets; and the green pellets are dried, preheated and roasted to produce finished pellets, and screened unqualified products are made into pellet return ore powder to return to participate in batching again. According to the method, the purpose of producing the high-quality pellets with the hematite as the main raw material is achieved, the problem that in the pellet production process, due to the fact that the proportion of the hematite is too high, the pellet index becomes poor is solved, the pellet melting dripping performance is greatly improved, and the technical problem that magnetite concentrate is mainly used for pellet production is solved; and secondary resources such as pellet return charge and boric sludge are fully utilized, so that the production cost of the pellets is reduced.

The invention discloses a preparation method of magnesium-calcium refractory aggregate with a core-shell structure, which comprises the following steps: granulating dolomite powder to form core particles, and uniformly adhering magnesium source powder to the core particles to form precursor particles with a double-layer structure; the adding amount of the magnesium source powder is controlled according to the mass ratio of the content of MgO in the magnesium source powder to the content of MgCa (CO3) 2 in the dolomite powder being (5-30): 100; and finally, heating and sintering the dried product of the precursor particles at the heating rate of 5 DEG C / min, and preserving heat to obtain the magnesium-calcium refractory aggregate with the core-shell structure. The method has the advantages of easily available raw materials and low production cost; the process is simple and suitable for large-scale production; the product is high in hydration resistance, high in refractoriness, excellent in slag corrosion resistance and wide in market prospect.

The invention relates to the technical field of rock wool boards, and provides a noise-reducing, sound-absorbing and heat-insulating rock wool board and a preparation method thereof. The noise-reducing, sound-absorbing and heat-insulating rock wool board is prepared from the following raw materials in parts by weight: 65 to 75 parts of basalt, 18 to 22 parts of dolomite, 12 to 18 parts of activated expanded perlite, 8 to 12 parts of cellulose nanofiber, 6 to 8 parts of stearic acid modified carbon nanotube, 5 to 8 parts of glass bead, 6 to 10 parts of binder and 45 to 55 parts of water. According to the noise-reducing, sound-absorbing and heat-insulating rock wool board provided by the invention, the raw material ratio and the preparation process are optimized, and the activated expanded perlite, the stearic acid modified nanotubes and the binder containing silicon dioxide are cooperatively used, so that the optimal noise reduction, tensile strength and hydrophobicity are realized.

The invention relates to the technical field of mine filling materials, in particular to a composite filling cementing material and a preparation method thereof, and the composite filling cementing material comprises the following components: oil shale slag, ironmaking slag, clay mineral slag, Portland cement, a composite activator and a polycarboxylate superplasticizer. The composite activator comprises the following components: water glass, sodium carbonate, metakaolin, anhydrous sodium sulfate, calcium sulphoaluminate, dolomite, silica fume, potassium feldspar and an excitation accelerator. The gelling part is completely composed of various industrial wastes, the materials are convenient to obtain, the manufacturing cost is low, the composite exciting agent can effectively excite the potential activity of the oil shale residues, the ironmaking slag and the clay mineral residues and promote the hydration reaction of the oil shale residues, the ironmaking slag and the clay mineral residues, and the prepared composite filling gelling material has good moisture resistance and good durability.

The invention discloses a moisture-proof and heat-insulating refractory material and a preparation method thereof, and relates to the technical field of refractory materials, and the moisture-proof and heat-insulating refractory material comprises dolomite, nano silicon dioxide, silica, an anhydrous binder and a moisture-proof agent. The synthesized moisture-proof agent is obtained by modifying asphalt through modified SBS obtained by grafting SBS and a monomer product containing terminal carbon-carbon double bonds, phosphate and a phthalonitrile structure, and has excellent flame retardance, high temperature resistance and waterproofness. And by using the nano silicon dioxide, the heat insulation performance of the refractory material can meet the requirements. The refractory material disclosed by the invention is excellent in refractoriness and moisture resistance and worthy of popularization and application.

The invention discloses a method for determining and analyzing primary and secondary elements in dolomite and magnesite based on ICP-AES (Inductively Coupled Plasma-Atomic Emission Spectrometry), and relates to the technical field of determination and analysis of the primary and secondary elements, the method comprises the following steps: obtaining determination samples of the dolomite and the magnesite, pretreating the determination samples, obtaining spectral line interference conditions of each element based on the determination samples, and determining the spectral line interference conditions of the elements based on the spectral line interference conditions; the method comprises the following steps: pre-processing measured data, drawing a calibration curve of each element, obtaining the interference condition of the calibration curve of each element, and carrying out ICP-AES measurement on the pre-processed measured data to obtain a characteristic spectral line. According to the method, the source and the influence degree of the interference spectral line are determined by analyzing the spectral line interference condition, then targeted measures are adopted for correction, and meanwhile, concentration measurement deviation caused by chemical interference, physical interference, ionization interference and other factors is found by evaluating element concentration interference factors, so that the accuracy of the concentration measurement is improved. And correction is carried out by means of optimizing a sample pretreatment method, adjusting instrument working conditions and the like, so that the reliability and the stability of the analysis method are improved.

The invention relates to the technical field of oil and gas geophysical exploration, in particular to a dolomite reservoir fracture-cavity system prediction method and device, equipment and a medium. The method comprises the steps that large-scale fractures of a reservoir in a research area are described by extracting seismic attributes, small-scale fractures of the reservoir in the research area are described by solving attenuation gradient attributes of different azimuth angles, and hole bodies of the reservoir in the research area are described by conducting pre-stack total porosity inversion. Therefore, large-scale and small-scale crack and hole body depicting results are obtained; and the dolomite reservoir fracture-cavity system prediction result in the research area is obtained through fusion. The problems that when a dolomite fracture-cavity system is depicted through logging data or seismic data in the prior art, fracture-cavity development characteristics cannot be described and predicted on the whole, fine depiction of fracture-cavity body seismic response outer contours cannot be achieved, and the accuracy of hole recognition and fracture depiction is relatively low are solved.

The invention relates to a method for preparing an acidified soil conditioner by using dolomite waste residues, which belongs to the technical field of soil conditioners, and specifically comprises the following steps: mixing activated dolomite, mineral source humic acid, a macromolecular adhesive and a fermented organic matter in a ratio of 1: 0.4: 0.001: 0.75; the acidified soil conditioner can be obtained by uniformly mixing the components, and the prepared acidified soil conditioner can remarkably improve the pH of acidified soil and increase soil nutrients so as to improve the crop yield, and can realize resource utilization of dolomite.

The invention discloses a method for measuring the content of calcium fluoride in dolomite-containing fluorite mine. The method comprises an acetic acid solution, a hydrochloric acid solution, a triethanolamine solution, a potassium hydroxide solution and boric acid. The method for measuring the content of calcium fluoride in the dolomite-containing fluorite mine comprises the following steps: S1, reagent proportioning; s2, preparing a calcium standard solution; s3, preparing an EDTA standard titration solution; s4, selecting an instrument; s5, preparing a sample; s6, step analysis; s7, content correction and determination; and S8, calculating a result. The invention belongs to the technical field of calcium fluoride content determination, and particularly relates to a method for measuring the content of calcium fluoride in dolomite-containing fluorite mine, compared with the prior art, the method solves the problem of dolomite dissolution when calcium carbonate is leached by acetic acid, and the content of calcium fluoride in the fluorite mine can be measured by accurately calculating the dissolution amount of dolomite. The measured calcium fluoride content is clearer, more reasonable and more reliable and approaches to a true value, and the process operation is simple and rapid, and is suitable for the requirements in the fields of mine production, assay detection and the like.

The invention belongs to the technical field of steelmaking, and particularly relates to a rapid slagging method for smelting first furnace steel after converter fettling, which comprises the following steps of: adding hot-state slag of a converter into a converter along with scrap steel when the smelting of the first furnace steel after converter fettling begins; and then molten iron is added into the converter, a proper amount of lime and light-burned dolomite are added, and rapid slagging is carried out. According to the method, the hot-state slag of the converter is used for replacing part of lime and dolomite for slagging, rapid slagging can be achieved within 5 min, and the dephosphorization rate reaches 45% or above. As the hot-state slag contains more TFe and alkaline CaO, and is higher in temperature and better in fluidity, the hot-state slag is added into the converter in the initial stage of smelting, and the TFe and the CaO are high in concentration, can be combined with acidic oxides and participate in an early-stage deP reaction, so that the problems of poor fluidity, long melting time, low alkalinity and low slagging rate of normal-temperature solid-state slag charge are solved; therefore, the problems of low deP efficiency in the early stage of converter steelmaking and alkaline lining erosion by acid slag are improved.

The invention relates to the technical field of refractory materials, in particular to a preparation process of hydration-resistant synthetic magnesia-calcium sand. Comprising the following steps: 1) grinding dolomite and magnesite into fine powder with the granularity of 200 meshes; (2) adding the workmanship dolomite fine powder and the magnesite fine powder in the step (1) into a high-speed mixing mill, adding cerium oxide and iron oxide red powder, and fully mixing; 3) adding water accounting for 22-38% of the total weight of the mixed material, and mixing for 45-60 minutes to obtain uniform wet powder without dry powder; (4) pressing the uniform wet powder into wet green bricks by using a brick press; (5) putting the wet green bricks into a drying kiln, drying for 24-30 hours at the drying temperature of 50-80 DEG C, and sintering in a high-temperature sintering device; the firing temperature is 1600 to 1700 DEG C; and 6) crushing the sintered green brick to finally obtain the magnesia-calcium sand. The magnesia-calcium sand prepared by the invention has good hydration resistance and high-temperature usability.

The invention discloses an advanced dynamic evaluation method for dolomite sanding characteristics. The advanced dynamic evaluation method comprises the following steps: determining mesoscopic and macroscopic thresholds of dolomite sanding degree grading as rock test static parameters based on an indoor test; extracting kinetic parameters and electrical parameters of the dolomite rock mass as advanced detection dynamic parameters based on geophysical advanced detection of missile-electricity combination; performing principal component analysis and correlation analysis on the rock test static parameters and advanced detection dynamic parameters, and constructing a dolomite sanding dynamic-static parameter quantitative conversion model by using RBFNN (Radial Basis Function Neural Network); training an intelligent grading evaluation model by taking the rock test static parameters as input and the sanding degree grade as output; and mapping the advanced detection dynamic parameters into rock test static parameters through the quantitative conversion model, inputting the mapped rock test static parameters into the intelligent grading evaluation model for verification and iterative optimization, and outputting a sanding degree grading result. Advanced prevention and control of sanding of the dolomite in front of the tunnel construction face can be achieved, and the ground disaster of sand collapse caused by sanding and sand gushing is avoided.

The invention discloses a smelting method of cold direct reduced iron in a Consteel electric furnace, belonging to the technical field of electric furnace steelmaking. The smelting method comprises the following steps: at the beginning of smelting, low-grade power supply is adopted, and at the same time of power-on, oxygen lances and carbon lances on the furnace wall are used to blow oxygen and spray carbon to produce foamed slag for submerged arc. After 1-3 minutes, scrap steel is continuously added by the Consteel system, and cold direct reduced iron is added through the fifth hole of the electric furnace. The molten steel in the furnace is heated by the electric arc, and the molten steel melts the metal materials in the furnace; during the whole smelting process, lime and light burned dolomite are added in batches. The addition amount of lime is 30-50 kg / t of steel, and the addition amount of light burned dolomite is 25-30 kg / t of steel. The invention helps to maintain the whole-process flat bath smelting, reduce the power consumption of electric furnace smelting, and reduce the smelting cost; it provides a technical solution for a short-process demonstration plant for the efficient use of direct reduced iron in an electric furnace, filling the domestic technical research gap in the short-process industry of electric furnaces.

The invention discloses a high-temperature well cementation cement expanding agent and a preparation method thereof, and belongs to the technical field of oil-gas well engineering well cementation materials. The high-temperature well cementation cement expanding agent is prepared from the following raw materials in parts by weight: 30-40 parts of dolomite; 10 to 20 parts of serpentine; 5 to 10 parts of hedenbergite; 5 to 10 parts of scolecite; 25-35 parts of slaked lime powder; 5-10 parts of quartz powder; the high-temperature well cementation cement expanding agent comprises the following chemical components in percentage by weight: more than 13wt.% and less than 23wt.% of MgO, more than 38wt.% and less than 55wt.% of CaO, more than 18wt.% and less than 32wt.% of SiO2, less than 3.5 wt.% of Al2O3 and less than 1wt.% of Fe2O3. The particle sizes of the high-temperature well cementation cement expanding agent are as follows: Dx (10) is less than or equal to 4 microns, Dx (50) is less than or equal to 10 microns, and Dx (90) is less than or equal to 20 microns. The invention also discloses a preparation method of the high-temperature well cementation cement expanding agent. Starting from cement main body minerals, through lattice solid solution, core-shell structure wrapping and other means, an expansion component and the hydration process of cement can achieve a synergistic reaction, and therefore the effective expansion effect is achieved in the cement gelling structure forming process.

The invention discloses a high-aluminum limonite and specularite ore blending and sintering method which comprises the following steps: 1) preparing primary pre-blending powder: pre-blending high-aluminum limonite, specularite concentrate powder, iron oxide scale, limestone powder and anthracite powder to prepare the primary pre-blending powder with the water content of 6.5-7%; (2) preparing a uniformly mixed material: blending the primary pre-blended material powder obtained in the step (1) with high-silicon iron ore powder and hematite and limonite powder to prepare the uniformly mixed material; 3) sintering and burdening: burdening the uniformly mixed material obtained in the step 2) with limestone, dolomite powder, quicklime, solid fuel and return mine, and 4) controlling the components of the sintered ore as follows: 2.3-2.5% of Al2O3, 5.7-6.5% of SiO2, 8-8.5% of FeO and 1.85-2.5% of MgO. According to the invention, while 20-30% of the proportion of the discount ore silk road powder in the total uniformly mixed material is increased, the sintering cost is reduced by 20-42 yuan / ton, the drum strength of the sintered ore is greater than or equal to 78.5%, the return mine rate is less than or equal to 27%, and the RDI + 3.15 mm is greater than or equal to 63%.