Patent ID: 7318288

Claim:
Apparatus comprising: a product dryer heated by a hot gas from a combustor; and a pollution abatement system that removes particulate pollutants in flue gas from the dryer containing combustible particulate pollutants and inert particulate pollutants, wherein: the pollution abatement system includes an electrified filter bed preceded by a cyclonic mix chamber that mixes flue gas from the dryer with gas from the combustor and removes the combustible particulate pollutants from the flue gas, and that passes a gas stream containing the inert particulate pollutants to the electrified filter bed, which removes the inert particulate pollutants from the gas stream, wherein the electrified filter bed includes a vessel containing a granular filter medium, an ionizer that imparts electric charges to the inert particulate pollutants in the gas stream, and electrodes that apply a polarizing electric field to the granular filter medium, wherein the dryer is a wood chip dryer, the combustible particulate pollutants are wood fines from the dryer and the inert particulate pollutants are fly ash from the combustor, and wherein the temperature of gas input to the cyclonic mix chamber from the combustor is substantially higher than the temperature of flue gas input to the cyclonic mix chamber from the dryer.