Title : Evaluation of an improved biomass cookstove performance and the traditional stoves of India: A comparative study
Abstract:
The cooking process has made easily digestible and richly nutritious food available to homo-sapiens. This has enabled humans to spare time to pursue higher purposes besides food acquisition. A predominant source of heat for food reparation has been the biomass conventionally. The availability of fuels like natural and petroleum gases and electricity-based devices in modern times has replaced biomass-based cooking for the affluent section of society. Still, a large chunk of the population depends on biomass as their primary fuel source for cooking purposes for various reasons, including the lack of last-mile supply chain infrastructure and the inability of hinterland people to afford them. The traditional biomass cookstoves have been pretty ineffective in terms of combustion efficiency and produce a lot of harmful emissions. Indoor pollution as the result of the use of traditional cookstoves has been responsible for chronic and severe repository illnesses, especially in women and children. In addition, the time and effort (resources) put in by the people for procuring the fuel biomass is ample. This also results in the loss of green cover of the trees when cut for firewood purposes. The 3.5 kWth top-lit updraft micro biomass gasifier-based cookstove is designed as per the stoichiometric calculation. The stove is prepared by mild steel 3 mm thick sheet. Grate and ash-pit are added to collect char and ash particles after the combustion process of the feedstock. The shape of the combustion chamber is cylindrical, whereas the shape of the ash pit is rectangular. In this stove, combustion is divided into two processes. Bottom air vents are gasified with sub-stoichiometric air and carbonaceous feedstock, which generates producer gas. This gas reaches secondary holes where combustion has occurred due to the natural draft. To increase the draft, the inner shape of the stove was prepared with a continuously decreasing diameter as the air went upwards. The secondary air gets heated by providing the annular space in the periphery of the inner part of the stove. This preheating of secondary air improves the thermal efficiency of the stove. It also works as a natural thermal insulation jacket, decreasing heat losses through the stove surface and avoiding needing separate insulation material augmentation. With the combination of intelligent utilization of natural draft and novel geometry, the complete combustion of biomass is achieved, resulting in a highly efficient combustion process and minimal harmful emissions. Experiments were conducted with wood as a feedstock with a traditional three-brick stove and an improved biomass cookstove. Different parameters, such as Specific fuel consumption, PM, fuel consumption, firepower, useful firepower, gas emission, etc., were investigated in this study.
