China is rich in iron ore resources, but most of them are low-grade ores, including many hematite, limonite, siderite, etc., which are characterized by low iron grade, fine crystal size, compact distribution with gangue, and difficult dissociation of monomers. Therefore, it is difficult to use conventional beneficiation methods for separation and cannot be reasonably utilized. With the rapid development of iron and steel industry, there are fewer and fewer rich ores available for utilization. Therefore, it is of great significance to effectively develop and utilize low-grade iron ore and complex symbiotic ores.

Nickel, as an important strategic metal material, has various advantages such as corrosion resistance, oxidation resistance, high temperature resistance, high strength and good ductility, and is widely used in modern industry. Nickel is mainly used to produce stainless steel. 65% of the world's total nickel consumption is used to produce stainless steel and 12% is used to produce heat-resistant alloys and non-ferrous metal alloys.

It is necessary to ensure that foamed acid (foamed dilute sulfuric acid formed after the liquid formed by mixing concentrated sulfuric acid, water and foaming agent is foamed by compressed air) fully wetts the lint on the surface of cotton seed, The mixing quality of cotton seed and foamed acid is directly related to the consumption of concentrated sulfuric acid, water and foaming agent, and affects the productivity of subsequent drying and defoiling equipment and the amount of residual acid in seeds.

The stirring system of VKM-5 Twin-shaft differential vertical kneader consists of mixing kettle, solid paddle and hollow paddle. The inner wall of the mixing kettle is a hollow thermal insulation layer, which is filled with 30 ℃ constant temperature water provided by the water supply system. The hollow paddle and the solid paddle are vertically installed.

Industrial solid waste not only pollutes the environment but also causes huge waste of resources, which is one of the important issues concerned by the comprehensive utilization of resources and environmental protection in the world. Therefore, large enterprises finally explore recycling technology through the successful application of cold briquette technology in solid waste recycling.

The large briquette machine consists of transmission motor, synchronous gear reducer, preloading device, main machine device,hydraulic system, belt conveyor and electronic control. Among them, the synchronous structure adopted by the transmission system makes the main engine transmission realize good design,manufacture, use and maintenance. The hydraulic device adopts the structure of small cylinder body and large tension force, thus realizing the purpose of reducing the quality of the whole machine and reducing the consumption of steel. The ball pressing roller adopts a combined structure, which realizes that vulnerable spare parts can be replaced on site, thus reducing the loss caused by the shutdown of the production line.

Forced conveying device with mixing function is one of the important equipment in plastic extrusion production line. The device adopts a screw with left and right rotation, driven by a deceleration motor. The materials at both ends of the screw are simultaneously transported to the middle of the screw by utilizing the conveying mechanism of the screw thread. When the materials transported in the left and right directions merge in the middle of the screw, some materials are forcibly transported to the processing equipment through the material conveying port which is in the middle of the mixing bin. Thus realizing the forced conveying function of the materials.