This study is devoted to elucidating experimentally the co-gasification characteristics of sewage sludge with a kind of other high calorific fuels such as plastic waste and to evaluating the possible energy effi-ciency when applying the gas to a power generation system. By varying air ratio, air temperature and the type of high caloric fuel, experiment was first conducted in a laboratory atmospheric bubbling fluidized bed gasifier to investigate the conditions necessary to maintain the product gas to have caloric values of about 1500kcal/m3N. It was found that the air ratio should be between 0.3 and 0.4, and the use of plastic fuel, compared to coal, is more reliable to achieve the desired caloric values of product gas. Based on these experimental results, a further evaluation with respect to an energy system consisting of gasification and power generation turbines demonstrated that the available power efficiency could be higher than 20% in a bottoming cycle with the use of both gas engine and steam turbines. The corresponding operating condi-tions for the gasifier were that the air ratio was approximately 0.3 and the air itself had to be preheated to 723K.
