DEVELOPMENT OF AN IMPROVED DOUBLE BURNER NATURAL DRAFT BIOMASS COOKSTOVE

Abstract

An improved natural-draft double burner biomass cookstove was developed. The study became imperative to minimize the increasing rate of deforestation, harmful gas accumulation as well as excessive fuel consumption and heat loss experienced in the use of the inefficient and traditional cooking method. The study was conducted in the Department of Agricultural and Bio-resources Engineering, Ahmadu Bello University, Zaria, Nigeria. The cookstove was designed based on performance, affordability, and usability, and it was constructed purely from locally available materials. Stainless steel was used to construct the stove cladding; it possesses lesser thermal conductivity of 14.9 W/mk as compared to aluminum and mild steel which have 174.6 W/mk and 80.2 W/mk, respectively. A 2 cm thick detachable internal insulation made up of fired clay was constructed and used to control conduction heat loss. Standard Water Boiling Test (WBT) version 3.0 was used to test the performance of the cookstove and the experimental data were collected and analyzed using Completely Randomized Design (CRD) at three (3) level of fuel quantity, three (3) level of air inflow rate and two (2) level of fuel size. The experiment was replicated thrice and the Statistical Analysis System (SAS) software was employed for the analysis. The result of the experimental analysis yielded a mean thermal efficiency ranging from 17.2 - 33.1%, mean specific fuel consumption of 0.019 - 0.089, mean time spent in boiling per given weight of water of 0.172 - 0.354 h/kg, and mean firepower of 0.458 - 3.117 kW. The performance indicators were in line with standard stove performance, and thus, recommended for use over the conventional biomass cookstove.