Recent testing has demonstrated that the 0.004 lb/MMBtu emission rate is not achievable with the BACT equipment that has been installed. This permit application is to reevaluate the potential impacts of the SO3 injection system and permit an H2SO4 rate that will be achievable given the specific ambient conditions and coal characteristics that exist at the Naughton Power Plant. After evaluating the information submitted by PacifiCorp and reviewing the RBLC for similarly controlled units, the Division considers installation of alkali wet scrubbers on Units 1 and 2, meeting an emissions limit of 0.0055 lb/MMBtu, and meeting a SO3 injection limit of 4 ppmv, annual average of four (4) quarterly tests, to represent BACT for Units 1 and 2. Project emissions were estimated based on potential to emit. The new limit is in effect for PM based on MACT UUUUU requirements of 0.03 lb/MMBtu for filterable PM for EGUs, which went into effect April 16, 2015. The potential to emit for Unit 1 is based on the limit of 0.03 lb/MMBtu PM (filterable) + 0.007 lb/MMBtu PM (condensable) and the design firing rate of the unit. The potential to emit for Unit 2 is based on the limit of 0.03 lb/MMBtu PM (filterable) + 0.011 lb/MMBtu PM (condensable) and the design firing rate of the unit. Condensable is based on maximum historical condensable rate plus projected incremental increase from Hg control technology. For Unit 1, the maximum historical condensable PM emission rate was 0.0070 lb/MMBtu and the incremental condensable PM increase from the mercury control technology (calcium bromide injection – CaBr2) was projected at 0.00037 lb/MMBtu. This provides a total projected condensable PM emission rate of 0.00737 lb/MMBtu which was rounded to 0.007 lb/MMBtu in the September 22, 2015 application to permit the Unit 1 and Unit 2 H2SO4 emission limits at 0.0055 lb/MMBtu. For Unit 2, the maximum historical condensable PM emission rate was 0.0111 lb/MMbtu and the incremental condensable PM increase from the calcium bromide mercury control technology was also projected at 0.00037 lb/MMBtu. This provides a projected total condensable PM emission rate of 0.01147 lb/MMBtu which was rounded to 0.011 lb/MMBtu in the September 22, 2015 permit application. Note that the projected incremental CPM increase of 0.00037 lb/MMBtu from the CaBr2 mercury control technology was included in the December 11, 2013 application to permit the Naughton plant’s mercury control technology systems.

Click Here For Complete Article Text

• BHE Environmental, Inc.

• Calcium Bromide

• SO3 Conditioning

• Article