Emissions analysis from combustion of eco-fuel briquettes for domestic applications

Abstract

In this study, flue gas emissions from combustion of eco-fuel briquettes in a ceramic lined stove were investigated. The eco-fuel briquettes were made of biomass such as spent coffee beans, mielie husks, saw dust, paper pulp and coal fines using a hand operated screw press. A combustion set-up consisting of digital weightometer, a ceramic lined stove and a complete chimney system was used. The emissions from the combustion process were measured using a Testo 350 gas analyser linked to the chimney system. The eco-fuel briquettes made from a mixture of biomass and coal fines burnt within the acceptable exposure limits as set out by the Occupational Safety and Health Agency (OSHA). The flue gas emissions from the combustion of eco-fuel briquettes were found to contain 74 parts per million (ppm) carbon monoxide (CO), 4.32 ppm hydrogen sulphide (H2S), 1.34ppm nitrogen oxides (NOx) and 3.67 ppm sulphur oxides (SOx). The measured gross calorific value was 18.9MJ/kg, with a burning rate of 2g/min. These properties make eco-fuel briquettes suitable for domestic applications. A survey conducted as part of this study also revealed a significant demand for eco-fuel briquettes in many informal settlements in Gauteng Province, South Africa, at a competitive selling price of R2.60/kg.