Emissions of Gases and Volatile Organic Compounds from Residential Heating: A Comparison of Brown Coal Briquettes and Logwood Combustion

Coal continues to be a major source of energy for residential heating in some parts of the world due to its low price and good availability. However, only little information on emissions for coal combustion in small-scale appliances, in particular manually-operated stoves, is available. This study investigates the emissions of gases and volatile organic compounds (VOCs) from brown coal briquettes (BCBs) burned in a typical Central European wood stove and compares them to emissions from spruce wood logs. Special emphasis was placed on the evolution of emissions over consecutive batches. In comparison to wood, BCBs made from Lusatian lignite showed higher emissions of compounds that were attributed to the decomposition of lignin, while emissions that were attributed to having originated from pyrosynthesis did not show significant differences between both fuels. Furthermore, a 20-fold higher emission factor for SO2 was obtained from BCB combustion, which is known for its deleterious effect. In addition to a reduction in the carbon footprint, replacing BCBs with logwood as a fuel for residential heating might be beneficial for human health due to vast differences in SO2 emissions, whereas a potential effect from the reduction of organic emissions is questionable due to the rather small differences in organic emissions.