The removal of suspended particles from gases by the aid of electrical discharges, using alternating or direct current. Alternating current agglomerates the suspended particles into larger aggregates, causing rapid settling, esp. if the gases are quiescent. Direct current is used when large volumes of rapidly moving gas, such as occur in smelter flues, are treated. The suspended particles within a strong electric field of constant polarity become charged and are then attracted to a plate (electrode) of opposite charge.