Influence of binder type on greenhouse gases and PAHs from the pyrolysis of biomass briquettes

Five blends prepared with torrified sawdust, coal plus either coal tar, coal tar sludge, paraffin or molasses designed to serve as binder in the preparation of briquettes were pyrolysed in a rotary oven. The coal and the torrified sawdust used in the preparation of the blends were also studied. The condensable gases were analyzed by gas chromatography (GC) and infrared spectroscopy (FTIR). The permanent gases were also analyzed by gas chromatography. The concentration of nineteen polyaromatic hydrocarbons in the condensable products was analyzed with special focus on those considered as priority and carcinogenic pollutants. The results obtained from FTIR were confirmed by those obtained by GC. It was found that the inclusion of biomass produces a decrease in the amount of (polyaromatic hydrocarbons) PAHs in the condensable pyrolysis products and an increase in the concentration of CO2 in the gases, although these gases are carbon neutral.