Overview of tungsten

Tungsten concentrate north, northwest and southwest have output, especially in the West from Guangxi, via Hunan, Guangdong, Jiangxi, Fujian to the east of the Nanling Mountains, the largest tungsten mine. The southern Jiangxi most concentrated, the size of hundreds of mines, Dajishan, West Huashan, Kuimeishan, Pangushan are the world famous tungsten mine. Our election the rule of tungsten minerals and abroad abroad long development of tungsten ore, mainly scheelite, the total production capacity of 60%. In China, although the scheelite has proven reserves of 3 million 760 thousand T, accounting for 71% of the total reserves of tungsten, but due to some large and superlarge tungsten polymetallic deposit ore composition complex, fine particle size distribution, metallurgical technology the technique has not yet been solved thoroughly, which at this stage is still in the mining of quartz vein wolframite, accounting for the recovery of ore quantity 90%.

Properties of tungsten

Tungsten is lithophile elements mainly exist in the form of tungstate pegmatite and hydrothermal deposits; known ore has about 15 species, there are two main types of wolframite and scheelite in.

(1) (Fe, Mn). WO4, also known as tungsten manganese ore, containing about 76% of WO3, brownish black to black color, semi metallic luster, the proportion is 7.1 ~ 7.9; the monoclinic crystal often with a thick plate, often Youzong grain surface. Wolframite often coexist together with quartz veins.

(2) from CaWO4, also known as scheelite, containing about 80% of WO3, usually grayish white, sometimes tinged yellow, purple, light brown color, color diamond shiny or oily luster, the proportion is 5.9 ~ 6.1; belongs to the tetragonal crystal often showed a double cone, aggregate irregular granular or dense block. Often with Scheelite molybdenite, galena and sphalerite coexist together. Tungsten ore known mainly quartz wolframite ore and skarn scheelite ore - and placer type.

Tungsten concentrate

Is the production of tungsten ferrotungsten, sodium tungstate, ammonium paratungstate (APT), ammonium metatungstate (AMT) main raw materials such as tungsten compound, its downstream products are mainly tungsten oxide, blue tungsten oxide, tungsten powder, tungsten carbide, carbide, tungsten steel, tungsten rod, tungsten wire etc..

Tungsten ore beneficiation technology, tungsten ore beneficiation process flow, tungsten ore dressing method:

Beneficiation process of tungsten concentrate is generally made of tungsten ore (or wolframite scheelite) by crushing, milling, gravity (mainly spiral chute, shaker, jig, centrifugal separator), flotation, magnetic separation, electric separation process, production reached the national standard of wolframite concentrate or Scheelite Concentrate, the main ingredients of tungsten trioxide the content of tungsten concentrate can be achieved more than 65%.

Tungsten concentrate decomposition method

The reaction between tungsten concentrate and chemical reagents, the formation of water soluble tungstate or insoluble tungstic acid and the separation of most impurities, is an important part of tungsten metallurgy process. The method for the decomposition of tungsten concentrate is divided into two categories: chemical decomposition method and acid decomposition method. The former belongs to the tungsten concentrate sodium carbonate sintering decomposition, black tungsten concentrate liquid caustic soda, sodium carbonate decomposition of scheelite decomposition is the hydraulic boil, white tungsten concentrate hydrochloric acid decomposition. Sodium tungstate solution and filtration residue were obtained by alkali decomposition. The crude sodium tungstate solution still contains more harmful impurities, and it should be purified by tungsten solution. In order to recover valuable metals from the decomposing residue and eliminate the pollution for the comprehensive utilization of slag alkali decomposition of wolframite. Hydrochloric acid is used to decompose tungsten concentrate to obtain crude tungstic acid and waste hydrochloric acid solution. The solution of sodium tungstate solution or sodium tungstate solution is obtained by using ammonia or sodium hydroxide solution. This solution is sometimes purified. Modern industry has formed a black tungsten tungsten concentrate mainly using caustic soda solution decomposition, Scheelite Concentrate the main use of hydrochloric acid decomposition method and sodium carbonate hydraulic decomposition method. Low grade white tungsten raw materials are commonly used sodium carbonate hydraulic decomposition method. In order to make effective use of tungsten resources, also use such as tungsten ore, refractory tungsten slime, such as tungsten concentrate, tungsten scrap material, non standard tungsten material decomposition processing. This treatment method and fine the decomposition method of ore is basically the same or similar. It is of great economic significance to improve the rate of decomposition of tungsten concentrate and tungsten and the recovery rate of tungsten. The decomposition rate of tungsten concentrate can reach 98% ~ 99%.

Schematic diagram of tungsten ore beneficiation process:

Quality requirements of tungsten concentrates:

Technical specifications for black and white tungsten concentrates specified in technical standards are as follows: