CAEPHT Centre of RES demonstrates improved cook stoves on farmer’s house at Samlik Marchak village of East Sikkim.
The Collage of Agricultural Engineering and Post Harvest Technology (CAU) centre of the Renewable Energy Sources (RES) conducted the demonstration of fuel saving improved cook stoves as Inverted downdraft gassifier to cook daily meals at farmer’s house (Mr Roop Narayan Bhattarai) in village Samlik Marchak of East Sikkim on February 23, 2011.
The Inverted Downdraft Biomass Gasifier Type Cook Stove using 1-3 kg wood or briquettes per filling is suitable for domestic use. Wood pieces and biomass briquettes are used as fuel. It offers the advantage of cooking/heating with gas while using a variety of biomass fuel.
The thermal efficiency of this cook stove is much higher (about 33%) as compared to the improved metal cook stove which ranges between 18-22% and 12-15% for traditional chulha for single and double pot very common in the villages of Sikkim.
This cook stove is called Inverted Downdraft Gasifier because in this case the air passes upward through the biomass fuel, through natural convection and meets the flaming pyrolysis zone where the reaction generates charcoal and fuel gas that gives smokeless environment inside the kitchen.
The “Inverted Downdraft Biomass Gasifier” type cook stove developed at SPRERI in Gujrat and tested at RES. It operates using natural convection of air. The rate of gas production and heating is controlled by the primary air supply to the gasifier.
The stove can be started and operated indoors, with sufficient ventilation without the need of any exhaust fan and it does not create odor of burning wood. The name comes from the fact that the fuel charge is lit “on the top”, and forms a layer of charcoal there; the flaming pyrolysis zone is below that, the unburned fuel is on the bottom of the pile; and primary air for pyrolytic gasification enters from the bottom and moves up, forming gas in the flaming pyrolysis zone.
The average consumption of the cook stove is about 1 kg/h which is sufficient for making a simple meal for a family of 4-5 persons. The men’s and women’s from nearby houses are gathered at the house of Mr Rup Narayan. The cook stove is filled with 2kg of sized wood. To start the cook stove some wood chips are places over the wood. A little quantity of kerosene is sprinkled over the wood chips and the fire is lit on. The butterfly valves provided at the bottom of the gasifier, to regulate intake of air, are kept in fully open position. After 2-3 minutes of letting the fire, good quality of producer gas starts generating. At this stage the cooking vessel is kept on the cook stove. It will take 10 minutes time to boil 3-4 litres of water.
Courtesy: Sikkim Mail