Effect of processing on emission characteristics of coal briquettes in cookstoves

Solid fuel usage for domestic cooking energy needs is an integral activity in several developing countries. Emissions from the daily usage of solid fuel lead to release of various pollutants which have adverse health effects. In the present study, an attempt was made to determine the influence of processing of fuel on emission characteristics from cookstoves. Processed fuel included carbonised and briquetted forms of raw coal which were tested in traditional and improved Indian cookstoves. Emission factors (EFs) were developed for fine particulate matter (PM2.5), Carbon Monoxide (CO), Elemental Carbon (EC), Organic Carbon (OC), Polycyclic Aromatic Hydrocarbons (PAHs) and trace metals. Overall, mass-based PM2.5 reductions of ~40 % by use of carbonised coal and ~47 % by use of coal briquettes were achieved. Carbonaceous aerosols were found to be the most dominant form of PM2.5 mass fraction (50–62 %) for all stove fuel combinations. PAHs and trace-metals represent ~1–5 % of the overall mass but can be critical from a health perspective. EFs of trace metals increased when shifting from raw to processed fuel pointing towards the need for standardization for processed fuel recipes.