With rapid developments of China's economy and industrial modernization, the increasing consumption of coal, oil and other fossil fuels have led to rapidly growing of abnormal aerosols, causing frequently regional haze episodes and having a significant negative impact on human health [1, 2]. As we all know, coal is the main fuel used for the government advocated centralized heating system throughout our northern cities, which is driven by large-capacity boilers in heating stations and power plants [3-5].