The heavy environmental loads in silicon carbide industries:Technological innovation and the results

SiC ceramics are widely used at high-temperature fields. The raw materials, manufacture process and application fields of SiC are all related to heavy energy consumption and pollutions, and bring high environmental loads. The resources consumption and pollution emissions in RB-SiC manufacture process were quantificationally estimated by input/output method. Difference between traditional technique and the new technique to produce SiC ceramics in China was also compared and analyzed. The Results show that SiC processes consume large quantities of resources because the furnace is open to environment and too much thermal-protection materials are used. Some suggestions were introduced to improve the traditional techniques and a new process was designed. It is the most important that the open furnace should be replaced by close vacuum furnace. Sintering and siliconizing process can be combined into one high-temperature process. As results of process simplification and vacuum sintering, resources and energy consumption and wastes emission were decreased remarkably.