PP&L unplugs Sunbury feeder
Pennsylvania Power & Light`s Sunbury Steam Electric Stations Unit 1 burns mainly anthracite silt. With this feed, the station experiences handling problems, even when supported by manual labor. Plant management looked to the Electric Power Research Institute (EPRI) for assistance. EPRI recommended the Stamet Solids pump. The pump has two discs mounted on a shaft to form a spool. The spool is enclosed within a housing, which forms a duct through the feeder. Solid material enters from above, is carried around by the spool, and exits after rotating between 200 and 300 degrees of arc.
The new system drastically reduced feeder plugging while delivering more coal without interruption, compared to the existing vibratory feeders at Sunbury. The feeder is expected to reduce plant costs by $111,000 per year and increase silt burn by approximately 6 percent at the same performance level. The feeder has achieved more stable mill and furnace operation and increased boiler efficiency. Excess air can be reduced from 24 to 16 percent, leading to a calculated further reduction in costs of $71,000 per year.