NOVELTY - The method involves burning organic substance in a combustor (7). Water is continuously supplied through the integrated heat exchanger in the combustor. Mixture of fluid fuel, oxidizing gas and alkali solution are continuously supplied to the combustor. Solids are isolated from the flown out fluid of the combustor with a separator.    USE - For electricity generation.    ADVANTAGE - As the fuel slurry includes liquid fuel and organic substance, low quality coal with sulfur is not used and since sewage sludge is also used as fuel, need for exhaust gas processing facility is eliminated. Recovery of carbon dioxide becomes simple.    DETAILED DESCRIPTION - The organic substances are selected from plastics, anthracite coal, bituminous coal, wood coal, lignite. The waste plastic includes polyethylene terephthalate bottle, house hold electric appliances, component of motor vehicle and computer. Waste of construction material of timber is also included. The liquid such as methanol, ethanol, trichloroethylene, benzene and polychlorinated biphenyl are included in the organic substance. A water separator (17) isolates oxygen and carbon dioxide. Oxygen is sent to the combustor as oxidizing agent. Carbon dioxide is collected as liquid carbon dioxide. Liquid nitrogen is manufactured by liquefying air in liquefier which has built in heat exchanger. The fluid slurry which includes organic substance such as algae from lakes and marshes, foodstuff waste, plant waste. The liquid fuel is preheated to 100-300degreesC and are supplied to the combustor by the modifier at 5-10 barometric pressure. The liquid fuel fluidizes the slurry in the combustor. The steam vapor generated in the heat exchanger, has temperature 500-700degreesC and pressure 10-40 MPa. The steam is used for driving the carbon dioxide isolator and turbine (10) to generate electricity. An INDEPENDENT CLAIM is also included for electricity generation system which includes heat exchanger for exchange of heat from the fluid flown out of the inorganic substance separator. The steam is used for driving the compressor.    DESCRIPTION OF DRAWING(S) - The figure shows the electricity generation system.    Combustor (7)    Turbine (10)    Water separator (17)