NOVELTY - The process comprises mixing dehydrated sludge in sewage water treatment plant with part of dried sludge, an inorganic fertilizer and an auxiliary material using a blender, adjusting the moisture content of the plant, and continuously extruding the mixture using single screw or a double screw machine (vertical or horizontal type). When the extruded sludge is not adhesive to each other, at low moisture content, the outlet of the screw extruding granulating machine/ strip producing machine is directly connected with the inlet of a rotary cylinder drier.    USE - The process is useful for treating sludge obtained from solid wastes.    ADVANTAGE - The process is capable of energy efficiently, easily and rapidly treating the sludge obtained from solid wastes in an economical manner without creating any environmental pollution.    DETAILED DESCRIPTION - The process comprises mixing dehydrated sludge in sewage water treatment plant with part of dried sludge, an inorganic fertilizer and an auxiliary material using a blender, adjusting the moisture content of the plant, and continuously extruding the mixture using single screw or a double screw machine (vertical or horizontal type). When the extruded sludge is not adhesive to each other, at low moisture content, the outlet of the screw extruding granulating machine/ strip producing machine is directly connected with the inlet of a rotary cylinder drier. When the extruded sludge is adhesive to each other (at high moisture content), the sludge inlet of the rotary cylinder drier is heightened appropriately to make part of high-temperature smoke to enter in the plant, making the smoke inlet to contact with the sludge for certain period time in vertical direction. The outlet of the screw extruding strip producing machine is always downward. When the sludge strip is extruded and contacted with the high-temperature smoke right away, the surface moisture is rapidly evaporated to make the sludge be separated from each other for drying and dewatering. One part of sludge is mixed with the wet sludge as returning charge after sent out of the rotary cylinder drier, the other part of sludge is sold as fuel of dried sludge or as fertilizer.