The district heating company “Rigas siltums” operates biomass fuelled boiler in Riga city. Three systems consisting of biomass boilers having a comparatively similar heat capacity and particle abatement units like multicyclons, electrostatic precipitators and flue gas condensers are compared. The main goal of the study is to evaluate the boiler plant as a system where solid particles are both emitted and caught. The results show that, the particulate matter can be efficiently trapped from flue gases by the particle abatement technologies, and the electrostatic precipitator with sufficiently large collection surfaces is able to provide appropriate flue gas treatment of the particulate matter in the biomass boilers also without pre-cleaning of the flue gas in multicyclons.