American Electric Power plans to begin the construction of new emission control systems at two of its power plants in West Virginia in the US. The controls will reduce nitrogen oxide (NOx) emissions on each affected generating unit by about 90 percent.
When in operation, the controls are expected to produce an overall reduction in NOx emissions from the two units of approximately 20,000 tons per year.
‘We plan to move forward with construction of Selective Catalytic Reduction (SCR) units on Unit 3 of our John E. Amos Plant at St. Albans, W.VA, and on the single unit at the Mountaineer Plant at New Haven, W.VA,’ said John F. Norris, AEP’s senior vice president of operations & technical services.
Both units are rated at 1,300 megawatts (MW). Construction on the two projects is slated to begin in the near future, with completion targeted for 2002. The total investment in the two projects is estimated at approximately $230 million.
The company will use a urea-to-ammonia system for the SCRs’ ammonia supply. The urea-based system is identical to the system that is being built at the company’s Gen. James M. Gavin Plant at Cheshire, Ohio. The system eliminates health and safety concerns associated with the long-term delivery and storage of the anhydrous ammonia used in conventional SCR systems.
SCR uses a chemical reaction to break down the NOx present in the exhaust gases that are released during the coal combustion process. The NOx is broken down into elemental nitrogen and water.
The projects are the newest element of the company’s overall program to comply with federal requirements to reduce NOx emissions. Nitrogen oxide contributes to the formation of ground level ozone, or smog.
The US.Environmental Protection Agency requirements cap NOx emissions at affected units during the May-through-September ozone season. Although these requirements are still in litigation, AEP is moving forward with its compliance efforts in order to schedule necessary engineering and construction resources.
Norris indicated that while the SCR technology being deployed on these generating units is the best available technology today, the company continues to explore new technological options that may ultimately prove more effective and cost efficient.
‘It is unfortunate that the federal regulations do not allow time for the development, commercialisation and installation of innovative multi-pollutant emission reduction technologies.
They have the potential to deliver superior environmental results at a lower cost of compliance,’ said Norris. ‘Nonetheless, we’ll continue to explore those new technologies as we work with the US EPA and our states to seek flexible implementation rules that might help us achieve those objectives.’
AEP has invested more than $160 million since 1993 to install low-NOx burners on its midwestern power plants. As a result, NOx emission rates have been reduced by approximately 30 percent per year below uncontrolled levels.
The company is also constructing the world’s first commercial-scale demonstration of a new emission reduction system at its Conesville Generating Station near Coshocton, Ohio.
The company expects to demonstrate and validate the effectiveness and performance of the Thermalonox emission reduction system during an eight- to 12-week test period this summer.
The system, created by Thermal Energy International of Canada, is designed to remove at least 75 percent of the existing NOx emissions from Conesville’s 375MW Unit 6.