SO3 Sampling and Detection Analysis Method in Coal-Fired Power Plant

Abstract

In December 2015, the executive meeting of the State Council decided to fully implement ultra-low emission and energy-saving transformation of coal-fired units by 2020, and to complete the transformation in the eastern and central regions in advance to 2017 and 2018. With the implementation of ultra-low emission transformation technology all over the country, the emissions of smoke, SO2 and NOx have been effectively controlled, and the number of heavy haze days in cities has been reduced, but no targeted control measures have been taken for the emissions of unconventional pollutants such as SO3. In fact, the harm of SO3 is far greater than that of SO2, which will not only cause corrosion of subsequent equipment, form ammonium bisulfate, and cause equipment blockage. If it is discharged into the atmosphere, it will react with water vapor and alkaline substances in the air, thus aggravating the generation of haze. Therefore, it is necessary to measure the SO3 in the flue gas of power plant accurately. But because of the special nature of SO3, its detection technology is a difficulty in this field, it is very necessary to carry out the research of high accuracy SO3 detection technology. In this paper, the most widely used control condensation method and isopropanol absorption method in SO3 sampling, as well as the titration method in SO3 detection are introduced in detail. Other methods of SO3 sampling and detection are briefly introduced.