Migration and distribution characteristics of organic and inorganic fractions in condensable particulate matter emitted from an ultralow emission coal-fired power plant.

Abstract

Condensable particulate matter (CPM) is the main part of total particulate matter (TPM) discharged from coal-fired power plants. In this study, a new analytical method was proposed for accurately quantifying the organic components including n-alkanes and phthalates in CPM that sampled from an ultralow emission coal-fired plant by using the Gas Chromatography-Mass Spectrometer (GC-MS) and the mixed standard solution. The organic fraction made up 53.13%, 50.90%, 52.44% of the CPM tested at the outlet of the low-low temperature electrostatic precipitator (LLT-ESP), the wet flue gas desulfurization (WFGD) and the wet electrostatic precipitator (WESP), respectively. The total concentration of 19 kinds of n-alkanes range from 0.328 mg/Nm3 to 0.854mg/Nm3 with C24-C30 becoming the major n-alkanes compounds in all sampling sites. The chief component of the tested phthalate was the di-n-butyl ortho-phthalate (DBP) which comprised 95.43%, 88.29%, 95.33% of the total of five kinds of phthalates. The WFGD contributed to the reduction of phthalates and the generation of n-alkanes while the effects on WESP were opposite. Furthermore, the existing air pollution control devices (APCDs) had no significant selection for the removal of n-alkanes causing the proportions of different n-alkanes were almost the same in different sampling sites. Also, the mechanism of the APCDs on the removal of CPM organic fraction was proposed primarily. The proportion of organic components measured in the organic fractions was less than 15%. Accurate quantification of other organic compounds and the mechanism of pollutant removal should be studied in the future.