NOVELTY - A refuse derived fuel apparatus (35) is provided to convert refuse into fuel from the coagulate of waste plastics which has undergone dechlorination by melting. A controller (50) is provided which controls the supply of waste plastics either to decomposition tank (36) for separating oil or to refuse derived fuel apparatus.    DETAILED DESCRIPTION - During dechlorination in the waste plastics processing apparatus (30), the waste plastics is melted in melting tank (34) to remove chlorine from it. A polyvinyl chloride amount measurement unit (32) is provided to measure polyvinyl chloride present in the discarded plastics by the fluorescent X-ray analytical method or spectroscopy procedure. The amount of polyvinyl chlorides is measured based on, the quantity of hydrochloric gas generated during melting of discarded plastics. The controller is controlled based on the amount of polyvinyl chloride in the discarded plastics. The controller controls the supply of waste plastics either to decomposition tank or to residue processing apparatus (41) for removing residue after completion of thermolysis in the decomposition tank. An INDEPENDENT CLAIM is also included for waste plastics processing method which involves switching between the oiling and the refuse conversion fuel formation process, based on the ratio of the chlorine present in the waste plastics.    USE -   For recycling of industrial wastes such as household electric appliances and plastic wastes of motor vehicle.    ADVANTAGE -   Enables switching of treatment of plastic wastes as there is a controller which controls the supply of waste plastics either to oiling process or to refuse conversion fuel formation process.    DESCRIPTION OF DRAWING - The figure shows the block diagram of waste plastics processing apparatus. (30) Waste plastics processing apparatus; ; (32) Polyvinyl chloride amount measurement machine; ; (34) Melting tank; ; (35) Refuse derived fuel apparatus; ; (36) Decomposition tank; ; (41) Residue processing apparatus; ; (50) Controller.