Clyde Bergemann Wins Contract for Electrostatic Precipitator (ESP) Rebuild in Michigan

The Genesee Power Station in Flint, MI is a biomass-fired steam boiler which burns wood waste, plus about 2% tire-derived fuel. The turbine/generator output is approximately 35 MW. Genesee contracted the Clyde Bergemann Power Group Americas (CBAM) for an Electrostatic Precipitator (ESP) rebuild. The scope includes design, supply and installation of new internals comprised of new collecting plates and RigitrodeTM electrodes for the first and third fields

of the existing ESP.

The Genesee ESP is a single chamber Joy Western rigid frame unit (circa 1995) collecting fly ash from a biomass-fired boiler. It is equipped with three mechanical fields, each with approximately 12 feet of treatment length and one electrical section per field. Collecting plate panels are segmented (18”) g-section with one Rigid Discharge Electrode (RDE) opposite each segment, 29 rows per field and lane spacing is 12”. In the inlet field the emitter tabs are flared or “spread”.This Joy design uses vertical trusses (four perelectrical field) to minimize sway. Cleaning on both frames is by pneumatic rapping system. Fly ash is collected in a trough hopper with continuous evacuation via a drag conveyor. The ESP is downstream of the ID fan.

Annual inspection information compiled over the years on the ESP determined it had

reached its life cycle on some critical internal components. Issues included missing Discharge Electrodes and Collecting Electrodes in the first and third fields, material thinning

outlet ducting of the ESP, air in leaking causing ash accumulation and eroding the ducting resulting in poor ESP performance.

While the RFQ indicated the desire to replace all supports and framing for both the collecting and discharge electrodes, CBAM assessed that such supports and framing could be reused and proposed a more cost-effective approach for upgrading the ESP. Recent inspections indicated the high voltage framing to be in satisfactory condition and the field arrangement revealed a reduction in collecting area would be required to accommodate different collecting system

supports.

CBAM proposed a retrofit that utilized a shop assembled collecting plate design with the same hanger mechanism currently in use in the ESP design. For the high voltage discharge electrodes, CBAM Rigitrodes were used, however, the pins were turned 90 degrees from their normal orientation to allow attachment to the high voltage framing in a method similar to that currently in use in the Joy ESP. This retrofit includes reusing all rapper hardware, also the existing rapper anvil beams and rapper trains.

After inspection and working with the customer, CBAM secured the order for rebuilding the ESP. The customer was confident with CBAM after cooperating over two plus years providing annual inspections and a cost-effective solution.