The zinc sulfide concentrate of Huludao Zinc Plant in China adopts high temperature roasting process. The high-temperature dust collected by the high-temperature electric dust collection and the soot collected by the secondary roasting of the rotary kiln and the double-blind ash and electric dust collected by the zinc concentrate of the first, second and fourth smelters of Shuikoushan Mining Bureau are high in cadmium. It is the raw material for cadmium. The components of this cadmium-containing soot are listed in Table 1. Table 1 Composition of cadmium-containing soot category Zn Cd Pb Cu As Fe Ss Sso 4 High temperature dust 40± 5~6 4~5 - - - - - Cadmium dust 18~20 18~23 - - - - - - Double ash 47～52 0.8 to 1.1 6~12 0.4 to 0.7 0.2 to 0.8 11~13 1 to 2 2 to 4 Electric dust 35～40 2 to 4 15~25 0.2 to 0.3 0.3 to 1 0.3 to 1.2 1.2 to 3 2 to 4 The third smelter of Shuikoushan Mining Bureau uses the all-wet process to treat the soot. The basic process is similar to the electrowinning process of Cu-Cd slag. The recovery rate of cadmium smelting is 88.75%, and the grade of cadmium is 99.99%. The Huludao Zinc Plant uses a wet-fire combined process to treat cadmium-containing soot. The production process is shown in Figure 1. The main advantage of this method is a simple process, high metal recoveries, the total recovery of cadmium in 1980 reached 71.29 percent, higher product quality, purity cadmium refined output stable at 99.995%. Figure 1 Huludao zinc plant extracts cadmium from soot The plant successfully tested the crude cadmium refining process in 1958. The cadmium rectification tower has a height of 5.585m and consists of 28 trays with a tray size of 360×250mm. The technical conditions for rectification are as follows: Enter the furnace crude cadmium grade /% 98 ~ 99 Combustion chamber temperature / K 1343 ~ 1353 Bottom temperature / K 1313 ~ 1323 Upper temperature / K 893 ~ 913 Gas condenser temperature / K 953 ~ 973 Liquid condenser temperature / K 843 ~ 863 Feeder temperature / K 773 ~ 823 Fine cadmium pot temperature / K 753 ~ 773 Crude cadmium melting pot temperature / K 723 ~ 773 Unit heating surface productivity / (kg · (m 2 · d) -1 ) 965 ~ 980 Cadmium recovery rate /% >99.7 Direct production rate of cadmium /% >98 Production of 1t cadmium consumption /% Caustic soda / kg 12 ~ 14 Coal / kg 650 ~ 700 Water / t 1.5 ~ 2 The cadmium slag component discharged from the bottom of the column is: 70% to 72% Cd, 13% to 15% Pb, 0.02% to 1.08% Zn, 3.1% to 4.6% Cu, 2.1% to 3.1% Fe, 3.5% to 4.9% As , 0.1% to 0.2% T1. This slag is sent to the recovery tank . Axle Shock Absorber,Gabriel Trailer Shocks,Trailer Brake Shock Absorber,Premium Shock Absorber ZHEJIANG ROADTAMER AUTO PARTS INC , https://www.road-tamer.com