Commissioning a Large Turbosorp~® Circulating Dry Scrubber (CDS)

摘要

The Turbosorp~® Circulating Dry Scrubber (CDS) has been supplied for four coal-fired power stations in the United States.The Turbosorp CDS systems for a 87 MW boiler and a 107 MW boiler have operated since 2007 and early 2009 achieving 95% or better removal of SO_2, SO_3, HC1 and mercury. These units fire middle to high sulfur content eastern bituminous coals. In both cases, the existing ESP's were taken out of service, and the CDS fabric filter captures the coal flyash from these units along with the CDS reaction byproduct.In 2009-2010, a Turbosorp CDS system was commissioned for a 238 MW boiler at the Deerhaven power station for Gainesville Regional Utilities (GRU). The GRU Deerhaven Turbosorp CDS demonstrated SO_2 removal levels exceeding guarantee requirements. This paper discusses scale up challenges and how they were resolved based on physical modeling. The experience gained commissioning the GRU unit was key to successfully starting a Turbosorp CDS for a 150 MW boiler. Tests of this second large unit in early 2010 confirmed SO_2 removal, lime consumption, power consumption and particulate removal guarantees. The system also removed greater than 95% mercury over the Turbosorp (98% coal-to-stack) without injecting carbon.Both of these larger systems treat flue gas from a variety of coals, and both retained existing Electrostatic Precipitators (ESPs) so that the CDS reaction products contain little flyash and unburned carbon. Because of the low carbon in the CDS reaction product, the systems include provision to inject Powdered Activated Carbon (PAC) to enhance mercury removal should it be required for specific fuels.