Flyash emission problems resolved

A significant reduction in the opacity of stack-gas emissions - from above 30% down to 16 to 25% - has been achieved on both 575-MW units at the Texas Utilities system's lignite-burning Big Brown station. In addition, particulate-emission levels have been cut from 1600 lb/h to about 600. The improvement in stack-emission conditions was achieved through use of a resistivity controlling agent, a spark-suppressing flue-gas chemical conditioner, the latest microprocessor controls, and additional transformer/rectifiers for the existing precipitator. The operation of the pollution control system is described.