Determination of Polychlorinated Diben-p-dioxins and Dibenzofurans in Flue Gas by High Resolution Gas Chromatography Coupled with High Resolution Spectrometry

摘要

In 1988 the first municipal solid waste (MSW) incinerator plant was built in Shenzhen, China. Since then Beijing, Shanghai and other big cities have built a few MSW incineration plants. MSW incineration has gradually been used in some cities of China due to its advantages such as significant volume reduction (about 90percent), mass reduction (about 70percent), and toxicity reduction of the waste and energy recovery. However, MSW incineration is sometimes considered to the general public as the secondary pollution source, because of concerns about is toxic combustion byproducts (TCBs). Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) are the most toxic compounds among the TCBs. In this paper, PCDD/Fs in flue gas produced from a MSW incinerator were isokinetically withdrawn and collected in a multi component sampling train. Then the PCDD/Fs samples were extracted, concentrated and cleaned up step by step. Finally, the determination of PCDD/Fs was carried out by high-resolution gas chromatography coupled with high-resolution mass spectrometry (HRGC/HRMS). The two PCDD/Fs emission levels were the similar, which was 0.115 and 0.096ng TEQ/Nm~(3) although different sampling time. The PCDD/Fs emission levels were lower than the PCDD/Fs emission regulation in China (1.0 ng TEQ/Nm~(3)) and close to the developed countries' regulations, i.e., 0.1ng TEQ/Nm~(3). 2,3,4,7,8-Pentachlorodibenzofuran (2,3,4,7,8-PeCDF) was the dominant congener of the total TEQ.