Technical Article, Thought Leadership & Public Relations for the Energy & Power Industry

Multi-pollutant Control Technology Assessment: Circulating Fluidized Bed Scrubber vs. Spray Dryer Absorber

VGB PowerTech | May 2016 | Amec Foster Wheeler

Krishnan & Associates wrote this whitepaper for our client Amec Foster Wheeler, and it was published in VGB PowerTech in May 2016. This thought leadership article discusses about how two pollution control methods work to reduce emissions from coal-fired power plants – Circulating Fluidized Bed (CFB) scrubbers and Spray Dryer Absorbers (SDA). Due to strict regulations from the U.S. Environmental Protection Agency (EPA) such as the Mercury and Air Toxics Standards (MATS) and the Cross-State Air Pollution Rule (CSAPR), power plants must quickly adjust to reduce mercury, metals, acid gasses, and particle emissions.

CFB scrubbers and SDAs are using different methods to remove pollutants. CFB scrubbers use boiler ash and lime to capture pollutants, resulting in great efficiency, minimal water consumption, and no liquid waste. They can handle more flue gas and use sorbents more effectively, but flue gas recirculation is required for optimal performance.

SDAs, on the other hand, spray lime slurry to absorb acid gases, turning them into solid particles that are then filtered out. There were some recent improvements in SDA technology, like better nozzle designs which have boosted performance, cut maintenance costs, and increased flexibility.

Both methods offer strong and dependable solutions for controlling emissions, with the choice depending on the specific needs of the plant, the type of fuel used, and regulatory requirements.

Written by K&A on behalf off Amec Foster Wheeler for publication in VGB PowerTech