FGD at Mae Moh Power Plant
Created: Monday, 20 April 2015 06:31
For more than 15 years, EGAT Mae Moh Power Plant has taken care of air quality in Mae Moh District, Lampang Province, to comply with the standard of Office of National Environmental Board. The air quality measurement of Mae Moh District in December 2014 from 11 air quality monitoring units showed that the averages of sulfur dioxide intensity within 24 hours, nitrogen oxide intensity within 1 hour, and dust within 24 hours were regarded as good-moderate level, the criteria classified by Office of National Environmental Board.
Mae Moh Power Plant uses lignite as the fuel to generate electricity. When the coal is burnt, the sulfur in the coal will chemically react with oxygen, contributing to sulfur dioxide. A large amount of this kind of gas in the atmosphere will have an impact on the health of people and environment. In the past the technology to get rid of the polluted gas was not as modern as today, causing the air pollution in the area.
However, since 1998 EGAT has installed Flue Gas Desulfurization System for units 4-13 with the efficiency to get rid of sulfur dioxide for 95%. Moreover, to assure that the air released from the power plant’s stack was clean complying with the standard, the monitoring system called Continuous Stack Emission Monitoring at stack (CEMS) has been installed to every stack of the FGD system for real time monitoring. According to the law, the sulfur dioxide released from the stack must not be more than 320 ppm. The sulfur dioxide intensity at the monitoring station within 1 hour must not be more than 780 microgram per cubic meter or 0.3 ppm. If the intensity is higher than 0.15 ppm for 6 minutes, the power plant must reduce its capacity by at least 120 MW or until the sulfur dioxide intensity will go back to the normal level, which is less than 0.05 ppm. There were also 14 air quality monitoring stations around Mae Moh Power Plant, 11 of them were installed by EGAT, while the rest was under the responsibility of Pollution Control Department.
The average of sulfur dioxide intensity within 1 hour,
released from Mae Moh Power Plant