Development of an Improved Biomass Stove and Performance Evaluation Using Three Types of Briquettes

Background and Objective: Several works on biomass cookstove design have been published under open and controlled conditions; however, fuel efficiency and smoky emissions remained their critical challenges. Proffering solutions to these challenges requires continuous research in development of improved stoves, which remained an active aspect of stove research and development. This study, therefore, contributed additional knowledge to stove research and development through the development of a clay-lining biomass stove. Its performance was evaluated using briquettes produced from untreated, torrefied and fermented sawdust mixed with different combinations of paper binders. Materials and Methods: Stove design factors were taken into consideration in design, while fabrication was done using designed parameters. Stove performance evaluation was performed using standard test procedures identified in literature. The stove thermal efficiency was determined using water boiling tests (WBT) and control cooking tests (CCT). Results: The developed stove showed good performance with a significant reduction in smokiness. When used in burning briquettes, it shows that heat transfer per unit surface area within the combustion chamber was 3.435 kW/hr, while the stove thermal efficiencies varied between 31.47-39.89% for untreated briquettes, 17.13-38.52% for torrefied briquettes and 23.84-39.89% for fermented briquettes, respectively. The unit cost of production of the biomass stove was NGN7, 300.00 (~US$7). Conclusion: The decrease in stove smokiness, favourable specific fuel consumption (0.56-0.68) and thermal efficiency performance, in addition to positioning for a competitive market and favourable production costs, make it acceptable.