Automation and controls of downdraft biomass gasifier systems

Abstract

All developing countries are targeting maximum efficiency in newlineharvesting energy and they are targeting 25% of primary energy demand by newline2020 with renewable energy sources. The relevance of a biomass gasifier is newlineimmense today, with the deteriorating of the non-renewable resources. newlineBiomass is a biological material from living organisms. As an energy source, newlinebiomass can either be used directly, or converted into other energy products newlinesuch as biofuel. Biomass is composed of carbon, hydrogen and oxygen. It is newlineused as a source of power generation and thermal applications. Power newlinegeneration from biomass has become a complement to conventional sources newlineof energy due to its contribution to the reduction of the greenhouse effect. Biomass gasification technology is used to convert biomass into newlinegas. The greatest challenge to researchers is automation and control of newlinedowndraft biomass gasifier system. The present study focuses on certain newlineinvestigation on woody biomass gasification. Two different downdraft newlinebiomass gasifier systems with capacities (135Kg/hr) and (6Kg/hr) have been newlineconsidered and operated under stable conditions using wood as fuel and air as newlinegasification agent. Preliminary experiments were carried out in both the newlinesystems and it was observed that the efficiency of the system was mainly newlinedependent on moisture content of the wood, size of the wood and temperature newlineof the process. Based on these experimental studies it is decided that the stable operation of gasifier needs a suitable controller. In this study, the fuzzy newlinebased intelligent control technique has been proposed to control the newlinetemperature and gas composition. Downdraft biomass gasifier system with capacity (135kg/hr) has newlinebeen considered to develop a static model and controller. The experimental newlinedata observed from this gasifier characterizes this process as a non-linear and newlineslow process, and hence the development of a model has become a challenge. The proposed model must be represent the non-linear characteristics of the newlineprocess. newline