Production and Characterization of Charred Briquettes from Various Agricultural Waste

ABSTRACT

This study seeks to char and briquette various agricultural wastes to be used as fuel in cookstove. To realize this, charred briquettes were produced from various agricultural wastes such as rice husk, maize cobs, palm kernel shell, and sawdust using the fast pyrolysis method at three different particle sizes (0.6 mm, 1.8 mm, and 2.36 mm) and compacting pressures (10 MPa, 20 MPa, and 30 MPa). Fuel tests such as physical test, proximate, and ultimate analysis, combustion test, and mechanical test were determined to assess the quality and suitability of the charred briquettes for use as fuel in cookstoves. The findings show that for all the three factors considered, palm kernel shell briquettes recorded the highest calorific value of 20,836.32 kJ/kg, volatile matter content of 17.3%, and fixed carbon of 76.5% while recording the least amounts of ash content of 2.7% and moisture content 3.95% compared to the other briquettes. The water boiling test results revealed that Palm kernel shell and sawdust briquette fuels reached their boiling point of 100 ℃ at the fastest time of 10 minutes. Furthermore, palm kernel shell briquette of particle size of 0.60 mm and compacting pressure of 30 MPa exhibited an outstanding performance than the other briquettes with regard to the values of specific fuel consumption of 2.38 kg/liters, burning rate of 0.00428 kg/min, shatter index of 96.93%, impact resistance of 500%, relax density of 753,291 kg/m³ and water resistance of 92.9%.

KEYWORDS:

• Briquette
• biochar
• proximate analysis
• ultimate analysis
• agriculture waste