Significant emission reductions of carbonaceous aerosols from residential coal burning by a novel stove

Carbonaceous aerosols (CA) are crucial components in the atmospheric PM_2.5 and derived from diverse sources. One of the major sources for CA is from the incomplete combustion of bituminous coal that has been prevailingly used by household stoves in rural areas for heating during winter. To efficiently eliminate the CA emission, a new household stove (NHS) was developed based on a novel combustion technology and CA emissions from the NHS and a traditional household stove (THS) were comparably investigated under the actual stove operation conditions in a farmer's house. Compared with the THS, the emission factors of organic carbon (OC), elemental carbon (EC), and water-soluble organic carbon (WSOC) from the NHS were reduced by 96%±1%, 98%±1%, and 91%±1% under the flaming process and 95%±1%, 96%±2%, and 83%±4% under the smoldering process, respectively. Additionally, the mass absorption efficiency of WSOC from the NHS reduced by 3 folds and the radiative forcing by WSOC relative to EC shrank remarkably by a factor of 3-8. Based on the reduction of emissions and light absorption of WSOC, the promotion of the NHS offers a possible solution to achieve the clean combustion of residential solid fuel.     

安庆市PM2.5碳质组分污染特征及来源解析

2020年3月2日—2021年2月28日在安庆市政务服务中心楼顶设置监测点,手工采集PM_2.5样品,运用多波段碳分析仪(DRI Model 2015)分析样品中碳质组分有机碳(OC)和元素碳(EC)质量浓度;利用OC/EC法、相关分析法和主成分因子分析法对PM_2.5中碳质组分的污染特征和可能来源进行解析。结果显示:安庆市手工采样期间PM_2.5平均质量浓度为(45.9±28.1)μg/m³,OC和EC的平均浓度分别为(8.0±3.4)、(1.4±0.6)μg/m³,在PM_2.5中占比为17.4%、3.1%。四季OC平均浓度分布为冬季(9.7±4.2)μg/m³ >春季(9.0±2.5)μg/m³ >秋季(8.3±2.9)μg/m³ >夏季(5.1±1.6)μg/m³,EC平均浓度分布为冬季(1.7±0.5)μg/m³ >春季(1.7±0.6)μg/m³ >秋季(1.3±0.4)μg/m³ >夏季(0.8±0.3)μg/m³。OC/EC范围为3.11~12.14,平均值为5.83,表明安庆市存在二次有机碳(SOC),SOC均值为(2.89±1.94)μg/m³,分别占OC和PM_2.5浓度的36.1%、6.3%;四季OC、EC相关性不显著,r均小于0.85,说明安庆市的碳质组分较复杂;在不同空气质量等级条件下,OC质量浓度随着污染等级的升高而逐渐升高,EC质量浓度随着污染等级升高而先升高后降低。利用主成分分析法进行来源解析发现,道路扬尘、燃煤、柴油车尾气是碳质组分的主要来源。