Kiln roasting process is an important part of the whole process, the temperature control in the roasting process is very strict, this aspect must have proficiency in operating workers, seriously, the first from the calcination temperature: the calcination temperature detection purpose is to better concentrate and sulfuric acid to control the reaction temperature. Sulfuric acid method according to the holding point calcination, the kiln temperature is high, but only a certain temperature kiln, and its exhaust is very strong corrosive. So the thermocouple and thermal resistance of the heat resistance and corrosion resistance of high performance requirements. Based on years of practice, Kiln porcelain protecting tube using platinum and rhodium - platinum thermocouple protection tube kiln using corundum platinum thermal resistance for ease of maintenance and disassembly, temperature measurement devices using plug-in installation. Operatives kiln and kiln according to the detected temperature, manual adjustment of the supply of heavy oil and compressed air to control the reaction temperature calcination. Another aspect ratios from acid mine detection: rare earth concentrate and sulfuric acid ingredients added by a certain percentage kiln firing. The ratio of double-loop measurement and control system, the entire system consists of concentrate sulfuric acid flow quantity and composition of the two detection control circuit, which is constant loop system concentrates, sulfuric acid loop servo system is that the ratio of concentrate through the loop quantity control the flow of sulfuric acid, to maintain a certain ratio between the two, to achieve accurate dosing. The above article by Henan YuFeng Heavy Machinery finishing release, reproduced, please indicate the source!