Design and performance test of multi-function stove for biomass fuel

Abstract: Rural China has a large number of biomass wastes, but the utilization efficiency of agricultural and forestry wastes are very low. there is a lot of waste in the traditional burning, it destroy the ecology，product indoor air pollution which affects the health of people, affect the sustainable development of rural areas. Household biomass stoves has a broad application prospects, it not only improves the thermal efficiency, reduce emissions of pollutants, conserve resources, improve the living conditions of rural residents, but also of great significance for China to achieve the sustainable development of the energy. The promotion of the biomass fuel stoves plays an important role for the promotion of the northern region the effective utilization of biomass energy. However, the biomass stoves in northern China, exist low thermal efficiency, substandard flue gas emission, tar smell, no consideration of both cooking and heating, no balance for both cooking height and climbing height of smoke which was used to warm the kang. In order to solve these problems, combined with the living habits of the rural residents in the northern region, design a biomass multi-functional stove in accordance with the relevant national standards. This design based on the design principles of biomass fuel stove, corn straw briquette fuel was used. Select layer burning as combustion method according to the fuel combustion characteristics. The main structure consists of air duct, components of grate, furnace, Cupping, circumferential water box, water jacket, chimney, feeding device, etc. The furnace volume heat release rate qmax is 350 kW/h·m3, Furnace volume is 0.02 m3, The adjustment of the flame height is 32 cm, grating area A is 0.015 m2. The chimney cross-sectional area F is 0.0072 m2 and white metal chimney of circular cross-section of diameter 10cm was used. Automatic feeder was used and feed rate is maintained at 2.5 to 3.0 kg/h, to be completed all night (12 h) of heating demand (heating and warming kang). The biomass multi-functional stove with functions of heating, cooking, bathing etc integrated, and its performance was tested according to NB/T34005-2011 and GB/T6412-2009.The results show that the rated thermal power was 8.0 kW, thermal efficiency was 69.7%, cooking thermal efficiency was 39.2%, cooking fire intensity was 39926 J/g, comply with the requirements of the general cooking and heating stove and meet the needs of the north of peasants' lives. The integrated thermal efficiency and flue gas emission indexes were tested by Energy Conservation Monitoring Center in Heilongjiang Province according to GB/T10180-2003 and GB/T16157-1996. The integrated thermal efficiency was 78.55%, thermal efficiency is higher than other stoves, it has good energy saving effect. Flue gas emission indexes were lower than the national standard. Dust emission concentration was 14.84 mg/m3, average concentration of NOx was 138 mg/m3, average concentration of SO2 was 14.8 mg/m3, average concentration of CO was 0.1%, Ringelman emittance class <1. It has a certain significance to promote the effective utilization of biomass energy in northern China，to improve rural residents living conditions and to protect the environment.