The first is that the temperature of the flue gas in the non-ferrous metal exercise is high, which is usually 300-900 ° C, and the highest can reach more than 1300 ° C. The temperature entering the electrostatic precipitator should generally not exceed 450 °C. Therefore, when the flue gas temperature is higher than this value, it is required to be cooled by a cooling device such as a waste heat boiler, a vaporization cooler, and an air preheater before the flue gas enters the electrostatic precipitator.
If the flue gas is rich in sulfur dioxide, its content is usually o. 5% to 1. o%, it is also necessary to control the minimum flue gas temperature entering the electrostatic precipitator so that it is not lower than the dew point of the flue gas flue gas (usually 200-275 ° C) to prevent the condensation of the flue gas corrosion equipment. The operating temperature of the electrostatic precipitator can usually be controlled between 250 and 350 °C.
Secondly, the dust bag is fine and rich in metal oxides, such as lead oxide and zinc oxide, which are formed by oxidation of metal vapor in the flue gas.
In the end, the intensive exercise of the dust-removing bag kiln greatly increases the dust concentration of the flue gas. For example, the dust concentration of the flue gas from the jubilant roaster is 200-300g/m3, and the flash smelting is 100g/m3, usually flue gas. For 15-80g/m3, set one or two-stage mechanical dust removal equipment in front of the electrostatic precipitator.