Nobuo Furuya

Hybrid-Type Electrostatic Precipitator

The hybrid-type electrostatic precipitator has been developed and in successful operation for 4 years at several plants in Japan, including a cement Lepol kiln. A major portion of dust, about 80 to 90 percent in weight, is collected in the dry stage located at the upstream side. The remainder is effectively removed in the wet stage. The slurry generated is fed to a thickener, in which water is separated from the dense slurry and recycled for reuse as irrigation water. The dense slurry, small in amount, can either be dried in a suitable drier using the apparent heat of the inlet gas, or be used for material processing such as dust pelletizing. The advantages of the hybrid-type electrostatic precipitator are the reduction in size and cost, the dust recovery in a dry condition, the reduction in irrigation water and slurry, and the effective removal in the wet stage of gaseous pollutants of flue gas, such as sulfur oxides, HF and HCl.