Advanced electrostatic enhancement of fabric filtration

Laboratory and pilot plant studies of a modification of the U.S. EPA's Electrically Stimulated Fabric Filtration (ESFF) method in which corona voltage on a center-wire electrode replaces the subcorona electrodes at the bag surface are discussed. The electric field which affects enhancement results from the high potential maintained on the center wire. The mechanism that supports the observed increase in gas flow consistent with the theoretical model involves the nonuniform deposition of the charged dust as a result of forces exerted on the particles in the electric field perpendicular to the bag. Laboratory results show an extremely low rate of pressure drop increase during the filtration cycle, only 10 to 30% of the rate associated with conventional reverse-air fabric filtration. Pilot plant data indicate a corresponding increase in flow through electrified bags. The rudiments of a mathematical model for describing the electrical deposition of the dust are presented.