Gasification Characteristics of Municipal Solid Wastes in a Batch Type Fixed Reactor

摘要

To provide reasonable operation conditions for the gasification of municipal solid waste (MSW), the effect of reaction temperature, residence time and air supply ratio were evaluated with a batch type fixed reactor. The reactor of 0.21m~3 was heated by external electric heater. Sample of 500g was inserted on the stoker that was placed at 150 mm above the bottom of reactor. K-type thermocouples were used to measure temperature inside reactor and sample. Air supply ratio was controlled 0 to 0.5 with nitrogen and air, and they were supplied to stoker from the bottom of reactor. MSW sample used in this experiment was consisted of garbage, plastics, paper and woods. Each component in sample was grinded below 10mm in diameter. The generation rate of gas was measured by differential pressure detector. Gaseous product was collected with gasbag at interval of five minutes, and then analyzed by using GC-TCD (HP5890-2). The generation rate, ignition loss and calorific value of solid products were also estimated. As the moisture of MSW evaporated in initial step, gaseous products was seems to decrease with elapsing residence time. It was also decreased as air supply ratio increased. Most of gaseous products were composed of CO, CO_2 and hydrocarbon including CH_4. All of hydrocarbon was decreased except CO as air supply ratio increased. The ignition loss and calorific value of solid products were 60～80% and 4,900～5,200kcal/kg respectively. Most of gasification reactions were almost finished within 15 minutes in this experimental condition.