Environmental impacts of biomass combustion for heating and electricity generation

Abstract

Environmental impacts are of primary importance for the design of combustion systems at any scale. An important issue for plant operators is to forecast the influence of changing the combustion process on the plant efficiency and pollutant emissions level at the same time. Biomass pyrolysis thermally converts biomass feedstock into biochar, bio-oil, and syngas in the absence of air/oxygen. Products generated from biomass pyrolysis offer options for alleviating greenhouse gas (GHG) emissions and for providing realistic options in mitigating coal combustion particulate matter (PM) emissions as the generated heat and electricity. Modern biomass combustion power plants are reduce waste-water discharges to levels that are accommodated within the local municipal sewer system. Water supply and water quality are critical issues for plant siting and operations, and most boiler facilities include a water treatment plant to produce high-purity water for the boiler. Air emissions generally constitute the largest environmental concern for most combustion systems and have become a principal inhibitor to expanded development in many regions with poor air quality due to the high cost of stringent emission control or emission offsets. Indirect effects leading to deforestation and agricultural expansion with high greenhouse gas emissions elsewhere in the world when biomass is produced as an energy crop may further reduce the sustainability of bioenergy and potentially increase exposures to criteria and other pollutants.