Influence of co-combustion of unsuitable fuels with standardized fuels in households on CO, OGC, PM, and PAH emissions

Abstract

Waste combustion in residential small-scale combustion units is not legal in the Czech Republic or other European Union countries. The resulting gaseous and particulate pollutants expose inhabitants to smells and toxic compounds and may damage their property and health. This study is designed to define the emissions of gaseous and particulate pollutants and determine the influence of municipal waste combustion on emission factors. Different types of solid fuels, municipal wood wastes (window frames, furniture chipboard), and mixtures of solid fuels with municipal wastes (namely, textiles, plastics, PET briquettes comprising a mixture of PET bottles + wood pellets + frying oil, paper, and floor coverings) were combusted in residential combustion units (such as gasification boiler, boiler with down-draft combustion, overfire boiler, and stove). Studies describing such an extensive range of waste samples combusted in different small-scale combustion units have not yet been published. Emission factors (EFs) for products of incomplete combustion (carbon monoxide (CO), organic gaseous compounds (OGC), and polycyclic aromatic hydrocarbons (PAHs) in gaseous and particulate phases) and particulate matter (PM) were within narrow intervals and lowest for standardized wood fuel (dry wood logs only) and 2-4 times higher on average for unsuitable coal samples (coal unsuitable for the particular boiler type used and coal combined with waste), for which values fell within broad intervals. The EFs of pollutants resulting from incomplete combustion (CO, OGC, and 16 PAH(total)) and PM were lowest for standardized wood fuel (dry wood logs only) and almost two or four times higher on average for unsuitable coal fuels (coal unsuitable for the particular boiler type used and coal combined with waste).