Chemometric analysis of air pollutants in raw and thermally treated coals - Low-emission fuel for domestic applications, with a reduced negative impact on air quality

The emission of pollutants into the air during the combustion of solid fuels in households is still a significant problem in many European Union countries, including Poland. These emissions are a significant source of many air pollutants formed during incomplete combustion and has been identified as one of the leading environmental risk factors for these populations. One of the solutions is to utilise thermally processed solid fuels. This article discusses the concentrations of pollutants emitted as a result of the combustion of conventional fuels and new low-emission fuel in out-of-class heaters. To gain better insight into the relationships between fuel type and flue gas quality, chemometric methods and variance analysis were used. Principal component analysis confirmed that the fuel type significantly influences the level of dust emissions and the total organic carbon and sum of polycyclic aromatic hydrocarbons in the dust. Clustering analysis identified how the concentrations of polycyclic aromatic hydrocarbons correlate with the amounts of dust and total organic carbon and showed that this correlation is proportional to the size of the molecule and consequently the number of aromatic rings. The use of low-emission fuel as a solid fuel in households, as our analyses have shown, can reduce the concentrations of dust, total organic carbon and polycyclic aromatic hydrocarbons by up to 50 times, thereby reducing air pollutants in cities.