Comparison of the gaseous and particulate matter emissions from the combustion of agricultural and forest biomasses

•Combustion of agricultural and forest biomasses was experimented in a 17.6 kW unit.•Quantity and quality of emissions were closely related to fuel characteristics.•Bulk density, air ratio, residence time and temperature could influence emissions.•Agricultural biomass combustion emitted most SO2, NO2 and PM than forest biomass.•NOx and SO2 emissions limits could be included in the Quebec regulations.

The aim of this study was to compare gaseous and particulate matter (PM) emissions from the combustion of agricultural (switchgrass, fast-growing willow and the dried solid fraction of pig manure) and forest (wood mixture of Black Spruce and Jack Pine) biomasses in a small-scale unit (17.58 kW). Concentrations of CO2, CO, CH4, NO2, NH3, N2O, SO2, HCl, and H2O were measured by Fourier transform infrared spectroscopy and converted into emission rates. Opacity was also evaluated and particulates were sampled. Results showed significantly higher emissions of SO2, NO2 and PM with the combustion of agricultural biomass compared to the forest biomass. However, further studies should be carried out so regulations can be adapted in order to permit the combustion of agricultural biomass in small-scale combustion units.