文摘
Attempts to reduce greenhouse gas emissions, coupled with the increasingly competitive price of biomass fuels against rising oil prices, have given impetus to the use of renewable biofuels in energy production. However, conventional biomass combustion systems produce significant air pollution making them undesirable particularly for public buildings such as schools. Thus, there has been growing interest in advanced wood combustion (AWC) technologies that have higher energy efficiencies and lower emissions. However, achieving increasingly stringent source emission regulations that serve to protect the public health may necessitate the application of pollution control technology on AWC systems. In the present work, the effectiveness of a model electrostatic precipitator (ESP) in capturing the emissions from a 150 kW wood pellet boiler was assessed. Stack gas sampling was performed using the EPA conditional test method CTM-039. Ash resistivity values were estimated using the Bickelhaupt model and measured ash composition, and were found to be consistent with the observed ESP performance. Size-dependent particle collection characteristics of the ESP revealed a slightly reduced collection in the size range of 0.2−1 μm and was independent of the boiler load. The ESP reduced particle mass to approximately 3 mg/m3 (0 °C, 101.325 kPa, dry gas and 13% O2) representing mass collection efficiencies of approximately 96−98%. It was concluded that ash resistivity would not be problematic for an ESP collecting dust from a typical AWC boiler.