The recycling process of waste plastics using coke ovens is now being studied. The effect of added plastic size on coke strength and coking pressure was investigated. The coke strength showed the mini-mum at the particle size of 10mm for polyethylene (PE) and 3mm for polystyrene (PS). The mechanism was well explained in connection with the weak coke structure formed on the interface between plastic and coal. Furthermore, it was shown that the addition of PE powder increased the coke strength and also increased the coking pressure during carbonization.
A circulating fluidized bed gasifier was developed to produce CO and H2 gas from municipal solid waste (MSW). MSW was gasified by using air at 1, 020-1, 170K. Faultless operation of gasifier with shred-ded and dried MSW was continued. During operation, the relations of temperature in free board and air feeding rate with the gas composition and product gas flow rate were analyzed. The equilibrium calculation of gasification with carbon discharge from gasifier was executed to esti-mate the crude gas composition. From the comparison between experimental data and calculated results, it was concluded that the product gas composition was determined mainly by water gas shift reaction under the conditions of temperature range of 1, 020-1, 170K and residence time of 5 seconds in the free board.