Gas pollution control apparatus and method and wood drying system

Abstract

Pollution control apparatus and method are disclosed in which hot exhaust gas containing pollutants including solid particles and hydrocarbon vapors is treated by transmitting such exhaust gas through a container containing wood members, such as wood chips, which serve as a filter media for filtering out such pollutants by causing such solids to deposit and such hydrocarbon vapors to condense upon the surface of the wood members. The contaminated wood chips are discharged from the filter and further processed into chip board or other commercial wood products thereby disposing of the pollutants. Lumber may be used as the wood members of the filter in a lumber kiln by deposition of solid particles on the rough surface of such lumber. The contaminated surfaces of the lumber are removed by a planer which produces smooth finished lumber and contaminated wood chips that may be processed into chip board or other commercial wood products. A wood drying system employing such pollution control apparatus and method includes a hot air dryer for wood or other organic material, such as a wood chip rotary dryer or a wood veneer dryer, which produces hot exhaust gases containing pollutants including hydrocarbon vapors and solid particles. This hot exhaust air is transmitted through a lumber kiln to dry lumber thereby conserving heat energy and causing solid particle pollutants to deposit on the surface of the lumber. The kiln exhaust air containing solid and hydrocarbon vapor pollutants is then transmitted up through a filter stack of wood chips.