Emission characteristics of harmful air pollutants from cremators in Beijing, China

The process of corpse cremation generates numerous harmful air pollutants, including particulate matter (PM), sulfur dioxide (SO2), nitrogen oxides (NOx), volatile organic compounds (VOCs), and heavy metals. These pollutants could have severe effects on the surrounding environment and human health. Currently, the awareness of the emission levels of harmful air pollutants from cremators and their emission characteristics is insufficient. In this study, we obtained the emission characteristics of flue gas from cremators in Beijing and determined the localized emission factors and emission levels of harmful air pollutants based on actual monitoring data from nine typical cremators. The results show that the emissions of air pollutants from the cremators that directly discharge flue gas exceed the emission standards of China and Beijing. The installation of a flue gas post-treatment system could effectively reduce gaseous pollutants and the emission levels of PM. After being equipped with a flue gas post-treatment system, the emission concentrations of PM10, PM2.5, CO, SO2 and VOCs from the cremators are reduced by 97.6, 99.2, 19.6, 85.2 and 70.7%, respectively. Moreover, the emission factors of TSP, PM10, PM2.5, CO, SO2 and VOCs are also reduced to 12.5, 9.3, 3.0, 164.1, 8.8 and 19.8 g/body. Although the emission concentration of VOCs from the cremators is not high, they are one of major sources of “odor” in the crematories and demand more attention. Benzene, a chemical that can seriously harm human health, constitutes the largest proportion (~50%) of the chemical components of VOCs in the flue gas from the cremators.

尸体火化过程会产生大量有害大气污染物，包括颗粒物（Particulate Matter，PM）、二氧化硫（Sulfur Dioxide，SO2）、氮氧化物（Nitrogen Oxides，NOx）、挥发性有机物（Volatile Organic Compounds，VOCs）以及重金属（Heavy Metals）。这些污染物会对周边环境及人体健康造成严重危害。当前，针对火化炉有害大气污染物的排放水平及其排放特征的认知仍存在不足。本研究基于北京市9座典型火化炉的实际监测数据，获取了其烟气排放特征，并确定了有害大气污染物的本地化排放因子与排放水平。研究结果显示，直排烟气的火化炉大气污染物排放浓度超过国家及北京市排放标准。安装烟气后处理系统可有效降低气态污染物及颗粒物的排放水平。加装烟气后处理系统后，火化炉排放的PM10、PM2.5、一氧化碳（Carbon Monoxide，CO）、SO2及VOCs浓度分别降低97.6%、99.2%、19.6%、85.2%及70.7%。此外，总悬浮颗粒物（Total Suspended Particulates，TSP）、PM10、PM2.5、CO、SO2及VOCs的排放因子也分别降至12.5、9.3、3.0、164.1、8.8及19.8 g/具遗体。尽管火化炉排放的VOCs浓度并不高，但它们是火化场内“异味”的主要来源之一，需引起更多重视。苯（Benzene）作为一种可严重危害人体健康的化学物质，占火化炉烟气中VOCs化学成分的比例最高（约50%）。