The Wisconsin Department of Natural Resources is out for comment until Nov. 20 on its preliminary decision to approve a Sept. 25 application from Wisconsin Public Service Corp. (WPSC) for a permit revision allowing at the Weston power plant temporary equipment to test the Refined Coal process with the addition of two additives for the control of mercury, and acid gas emissions including NOx and SO2.
The two additives are a liquid additive called MerSorb and a sold additive called S-Sorb. The tests would be done on Units 3 and 4. WPSC has requested a Research and Testing (R&T) exemption from construction permit requirements.
The maximum additives rates are different for the two units. The tests would be for a maximum of 60 operating days on each unit.
- For Unit 3, the maximum additive rate for S-Sorb to be used is 1,120 pounds per hour at a maximum of 234 tons of coal per hour. The maximum additive rate for MerSorb is 11 pounds per hour.
- For Unit 4, the maximum additive rate for S-Sorb to be used is 1,600 pounds per hour at a maximum of 319 tons of coal per hour. The maximum additive rate for MerSorb is 15 pounds per hour.
Said the Wisconsin Public Service website: “The Weston Power Plant site, near Wausau, in central Wisconsin, is home to three fossil-fueled electric generating units that make electricity for WPS customers. Weston 4, the newest unit, is a state-of-the-art, 595-megawatt electric generator that uses clean coal technologies — making it one of the cleanest power plants of its kind in the country. Weston 4 began operating on June 30, 2008. WPS owns 70% (416.5 MW) and Dairyland Power Cooperative of La Crosse, WI owns 30% (178.5 MW). Weston Unit 3 began operating in 1981, Unit 2 in 1960 and Unit 1 in 1954. Unit 1 was retired in 2015.” Notable is that Weston Unit 2 was recently switched from coal to natural gas.