The main pollutants in cemented carbide production are soot, waste residue and wastewater, among which soot has the greatest impact on the environment. According to the regulations, waste gas can be divided into two categories: waste gas containing particulate matter and waste gas containing gaseous pollutants. The waste gas from ferroalloy factory comes from submerged arc furnace, refining furnace, roasting rotary kiln, multi-layer mechanical roasting furnace and metal aluminum smelting furnace. Ferroalloy factory has a large amount of exhaust gas and high dust concentration. 90% of the waste gas is silicon dioxide, and it also contains chlorine, nitrogen oxides, carbon monoxide, sulfur dioxide and so on. The most serious pollution in waste residue and wastewater is chromium compound and nickel compound.
The State Economic and Trade Commission, the State Environmental Protection Administration and other departments also jointly issued the Opinions on Accelerating the Structural Adjustment of China's Ferroalloy Industry (No.1999), proposing to stop all kinds of ferroalloy electric furnaces (furnaces) and blast furnaces before 2005.