52 results about "Wet sieving" patented technology

Provided is a fumed silica for chemical-mechanical polishing with which post-polishing scratches occurring on a surface of an object to be polished can be significantly reduced, and which is importantfor miniaturization and multi-layering of a structure. The fumed silica according to the present invention has a BET specific surface area of 57-400 m<2> / g. In a liquid dispersion which is obtained by ultrasonically dispersing 6.25 mass% of this fumed silica in water at a vibration frequency of 20 kHz and an amplitude of 15-25 mu m for 3 minutes, the amount of residues on a sieve is 5 ppm or lessas measured by wet sieving using an electroformed sieve having a mesh opening size of 5 mu m.

The invention provides a preparation method for fine rubber powder. The preparation method comprises the steps of raw material treating, grinded material mixing, grinding, wet sieving, dehydrating, drying, dry sieving and packaging. According to the preparation method for the fine rubber powder provided by the invention, pre-crushed coarse granular rubber blocks and water are sufficiently mixed, and then are grinded in a circulating mode in a closed assembly line, and automatic drying, sieving and packaging of rubber powder are realized. The preparation method is high in degree of automation, is low in cost, and can be used for preparing ultrafine-grain fine rubber powder without pollution. The fine rubber powder prepared by the preparation method is combined with the surface of a raw rubber group so as to be in canine-tooth-alternating embedding, and therefore, net-shaped contact area is greatly increased in a spatial three-dimensional direction, combination of rubber powder and virgin rubber can be remarkably improved, and combination strength, toughness and wear resistance of glue are greatly enhanced.

The invention provides a method for preparing potassium chloride from a solid ore containing potassium, ammonium and magnesium. The solid ore contains the following components in percentage by weight:5.1%-5.9% of potassium ions, 1.0%-1.4% of ammonium ions, 9.5%-10.0% of magnesium ions and 35.2%-37.1% of chloride ions. The method comprises the following steps: (S1) crushing the solid ore containing potassium, ammonium and magnesium, and sieving, so as to obtain a first screen underflow; (S2) mixing the first screen underflow with water in a mass ratio of (100) to (50-70) to adequately decomposing the first screen underflow, carrying out wet sieving by virtue of a 40-80-mesh sieve, and carrying out solid-liquid separation, so as to obtain a second screen underflow; and (S3) carrying out primary flotation on the second screen underflow so as to obtain a first flotation concentrate, and carrying out washing, solid-liquid separation and drying, so as to obtain the potassium chloride product. According to the method, a decomposing-sieving-floatation process is formulated according to the constitution of the solid ore containing potassium, ammonium and magnesium and is utilized for preparing potassium chloride, obtained potassium chloride can be used as a production raw material, the whole process flow is simple and low in cost, the utilization problem of potassium is solved, and theresource utilization rate is effectively increased.

The invention relates to the technical field of pesticide for controlling rice sheath blight diseases and false smut, in particular to a suspending agent of thifluzamide and tebuconazole composite pesticide and a preparation method of the suspending agent. The suspending agent is prepared by the following ingredients in parts by weight: 20 parts of thifluzamide, 32 parts of tebuconazole, 18 parts of emolsifier and 30 parts of solvent. The prepared suspending agent is obviously superior to products prepared according to other proportions in suspensibility, persistent foamability, wet sieving test, thermal stability and the like. Experiments verify that the cotoxicity coefficient of the suspending agent reaches 154.19, the suspending agent falls in an obvious synergistic action scope, and preparations mixed in other proportions cannot reach the obvious synergistic action scope. In addition, the actual toxicity of different proportions is not raised with theoretical toxicity, and no change law exists between the actual toxicity and the theoretical toxicity. The suspending agent of the thifluzamide and tebuconazole composite pesticide is suitable for controlling the rice sheath blight diseases and the false smut, and has good popularization and application values.

The invention relates to the technical field of mineral processing, in particular to a low-grade iron ore roughing process and mineral processing equipment. The beneficiation process includes coarse crushing, primary fine crushing, and dry screening. The steps are as follows: secondary screening of ore materials, secondary fine crushing of the screened coarse ore, wet rough separation of fine materials, and selection of fine ore The raw material is coarsely selected iron ore products. The beneficiation equipment includes coarse crusher, fine crusher, dry screening machine and storage bin. After the storage bin, there is a set of wet roughing unit, including sequentially connected conveyor belt, secondary screening machine, wet fine crusher, wet type Sieving machines and wet roughing machines. The wet fine crusher is a wet hammer crusher, and the wet rough separator is a wet coarse iron ore strong magnetic separator equipped with a water adding device. The screening feeder is a vibrating screen with an eccentric vibrating device. Compared with the existing technology and equipment of the same scale, the production of the same low-grade iron ore can be sorted by 1-2 times under the same power consumption conditions, so as to make full use of low-grade iron ore resources.

The invention discloses an isotropic crosslinking beta-cyclodextrin / tungsten carbide composite microsphere and a preparation method thereof. The preparation method comprises the following steps: firstly, beta-cyclodextrin is dissolved into a sodium hydroxide aqueous solution, and the mixture is dripped with epichlorohydrin and undergoes stirring reaction under heating condition, so as to generateviscose; secondly, the viscose is added with tungsten carbide powder, oil dispersed phase and a dispersant under the condition of mechanical stirring to form a reversed phase suspension dispersion system; thirdly, the epichlorohydrin is added into the reversed phase suspension dispersion system, and the composite microsphere is obtained after mechanical stirring reaction; and fourthly, after the reversed phase suspension dispersion system is cooled, the composite microsphere is filtered, cleaned and neutralized, and subjected to wet sieving and expanded bed floatation. The composite microsphere developed by the method has the advantages of good hydrophilicity and sphericity, stable properties, low cost, high density, easy adjustment and so on, and can be used as a substrate during the process of expanded bed absorption as shown by an expanding performance test experiment.