Colorado Springs works on air permitting for SO2-controlled Nixon coal unit

The Colorado Air Pollution Control Division is taking comment until Nov. 26 on a draft permit covering an SO2 emissions change for the 227-MW Unit 1 of the Ray D. Nixon Power Plant of Colorado Springs Utilities.

At Nixon, the lone coal-fired boiler typically utilizes low-sulfur, sub-bituminous coal, and Unit 1 will use a Lime Spray Dryer (LSD) scrubber control system to reduce SO2 emissions. The goal is for construction of the LSD to be completed in 2017, with tuning to begin in June 2017 and to complete testing in September 2017.

Colorado Springs Utilities (CSU) requested a Construction Permit modification for the Ray Nixon Power Plant on June 10 to incorporate a facility-wide sulfur dioxide (SO2) emission limitation required under the 2010 1-hour SO2 Primary National Ambient Air Quality Standard (NAAQS).

Unit 1 consists of one Babcock and Wilcox, Pulverized Coal Wall Fired Dry Bottom boiler, firing coal or coal/woody biomass blend. The boiler is equipped with a Western Precipitation Thermoflex baghouse for Particulate Matter (PM) emissions control, a Lime Spray Dryer Absorber for SO2 emissions control, Activated Carbon Injection (ACI) for Hg emissions control, and Ultra Low NOX Burners and Over Fire Air (being installed in Fall 2016) for NOx emissions control.

This permit action results in a decreased amount of SO2 emissions for the year 2017 (about a 40% decrease) and future years when compared to the facility’s 2014 actual emissions. Within 180 days after the commencement of operation, and completion of the testing period of the Lime Spray Dryer Absorber (LSD) and the Activated Carbon Injection (ACI) control devices, compliance with the conditions contained on this permit need to be demonstrated to the division. 

About Barry Cassell 20414 Articles
Barry Cassell is Chief Analyst for GenerationHub covering coal and emission controls issues, projects and policy. He has covered the coal and power generation industry for more than 24 years, beginning in November 2011 at GenerationHub and prior to that as editor of SNL Energy’s Coal Report. He was formerly with Coal Outlook for 15 years as the publication’s editor and contributing writer, and prior to that he was editor of Coal & Synfuels Technology and associate editor of The Energy Report. He has a bachelor’s degree from Central Michigan University.