At present the world known minerals can be divided into 50 kinds of natural elements, intermetallic compounds, sulfide, oxide, hydroxide, silicate (Xi Shi) (Gui Xikuang), sulfur stannates (Huang Xikuang), and other types of borate. In the Department of minerals in the crust and lithosphere are mainly cassiterite, common minerals and tetrahedrite tin, Franckeite, sulfur ore, canfieldite, cylindrite, nordenskioldine, Malaya stone, Ta tin etc. more than ten kinds of other ore geology and minerals only rarely, significance. Little tin industrial minerals, with the existing technology of metallurgical industrial value, tin material only cassiterite and tetrahedrite tin, and dominated by cassiterite. Pure cassiterite (SnO2) containing 78.8% tin, but because natural cassiterite often contain iron, manganese, tantalum, niobium, indium, gallium, germanium, tungsten, vanadium, scandium and beryllium and other elements, among which the most iron tin content, so natural cassiterite is only 70%-77%. Pure cassiterite is colorless and transparent, natural cassiterite due to impurities of different elements and the different colors, the common brown and brown.

The physical properties of tin cassiterite: Mohs hardness of 6-7, crisp. Density 6.8-7.0g/cm3. Cassiterite rocks and acidic magma deposits in genesis, especially has close relationship with the granite. In various types of tin deposit of cassiterite output, the cassiterite quartz vein and hydrothermal cassiterite sulfide deposit in most industrial value. The primary cassiterite ore by weathering damage, often the formation of tin ore. Tetrahedrite tin (Huang Xikuang) molecular formula Cu2FeSnS4. The chemical composition (mass fraction,%): Cu 29.58, Fe 12.99, Sn 27.61, S 29.82. Steel gray. Tetrahedrite tin Mohs hardness is 3-4, brittle. The density of 4.3-4.4g/cm3. It is a hydrothermal origin, is widely distributed in W-Sn quartz vein or cassiterite sulfide deposit are often output, but the distribution volume is much less tinstone. Oxidation and decomposition in tetrahedrite tin in the oxidized zone, and the formation of tin hydroxide - acid mine white amorphous tin (SnO2 - NH2O).

Tin ore dressing method, tin ore beneficiation process due to the density of cassiterite than coexisting minerals, so the traditional tin ore beneficiation process for gravity separation. With the passage of time, ore particle size of tin in thinning, which appeared in cassiterite flotation process or centrifugal concentrator. In addition, because there are a variety of iron oxide minerals Tin Minerals, such as magnetite, hematite and limonite, these minerals by flotation and gravity are not well separated and cassiterite, so in recent years in the tin ore beneficiation process the magnetic separation. Most of the current use of beneficiation process or gravity separation process + flotation process, the process is: the crushed ore to 20mm, a closed circuit grinding to 0.15mm (150 mesh) accounted for 60% to 65%, the first spiral chute roughing, after the election did not reach the monomer dissociation of middlings into the two segment to 0.074mm (re grinding ball mill 200) then the gangue and ore intergrowths are removed by centrifugal separator. If there are many similar elements in the proportion of the additive concentrate flotation take mixed flotation a crude two and a fine grinding to 0.074mm; copper sulfur separation accounted for 95% of a crude copper concentrate produced two cleaners three, and sulfur concentrate; re mixed flotation tailings after sulfide. The one or two section of the bed; a washing mud; selection; rough tin concentrate in sulfur flotation, producing tin concentrate, rich middlings. Another technological process was as follows: first, the crushed ore to -20mm after sieving into 20 ~ 4 and 4 ~ two grade 0mm, 20 ~ 4mm in heavy medium cyclone pre. Cyclone valued products after a period of grinding after the jigging jig primaries, tail mine 2mm vibration sieve in +2mm as waste tailings, -2mm enters the table classification. The jig and table concentrate and middlings by grade two poor into rich system, were re grinding and mixing flotation. Mixed flotation tailings of tabling don't qualified tin concentrate; mixed flotation concentrate by fine grinding and flotation separation of lead and zinc, and output lead antimony concentrate and zinc concentrate. Re entered the slime Phi 300mm cyclone overflow, followed by 125mm and Phi Phi 75mm hydrocyclone group for removal of fine mud, sand, concentrated after flotation of cassiterite flotation desulfurization.

Tin ore dressing method, tin ore beneficiation technology, tin ore beneficiation process: