Corrosion Effects of Calcium Chloride Injection for Mercury Control on the Pollution Control Equipment

Vijay Sethi ; M.P. Sharma

关键词: AIR POLLUTION CONTROL;    CALCIUM CHLORIDES;    COAL;    CORROSION;    CORROSIVE EFFECTS;    FLUE GAS;    MERCURY;    POLLUTION CONTROL EQUIPMENT;    POWER PLANTS;    REMOVAL;    TESTING;   

DOI  :  10.2172/993824
RP-ID  :  None
PID  :  OSTI ID: 993824
Others  :  TRN: US201101%%230

美国|英语

来源: SciTech Connect

【 摘 要 】

In response to the Clean Air Mercury Rule (CAMR) of 2005, Black Hills Power (BHP) initiated testing of a calcium chloride (CaCl{sub 2}) injection method in their Wygen 1 (Gillette, WY) coal-fired power plant to help lower mercury emissions. In 2006, Babcock & Wilcox (B&W) was contracted to test their CaCl{sub 2} technology in-situ by adding a CaCl{sub 2} solution onto the raw, pre-pulverized coal during normal operation of Wygen 1. Follow-up tests were conducted by BHP in 2007. Data were collected from these two time periods and analyzed by a collaborative investigation team from Western Research Institute (WRI) and the University of Wyoming (UW) to see if there were any effects on the current air pollution control systems. During a CaCl{sub 2} injection period in 2007, corrosion was monitored in the flue and recycle ash system by placing corrosion coupons in strategic locations to test if corrosion was enhanced by the CaCl{sub 2} injection. While the CaCl{sub 2} produced a reduction in stack mercury levels, there was some evidence of beneficial impacts on the removal of SO{sub 2} from the flue gas during CaCl{sub 2} injection. Data on NOx remained inconclusive. It was also discovered that corrosion was enhanced significantly in the Spray Drier Absorber (SDA) vessel and corresponding outlet ductwork during CaCl{sub 2} injections. Further studies are being carried out in the field and lab to better understand the corrosive effects of CaCl{sub 2} to help formulate operation controls to manage the increased corrosion rates.