METHOD FOR JUDGING END POINT OF DECHLORINATION TREATMENT AND APPARATUS FOR DECHLORINATION TREATMENT

摘要

PROBLEM TO BE SOLVED: To easily judge the end point of dechlorination treatment at a low cost in the thermal dechlorination treatment of a chlorine-containing plastic by measuring the flow rate of waste gas discharged from the reactor. SOLUTION: A plastic material containing a chlorine-containing plastic (e.g. polyvinyl chloride) is roughly crushed, charged into a reactor 1 and mixed preferably with an organic solvent (e.g. diesel oil). The reactor 1 is heated to the dechlorination temperature and the discharged waste gas is passed through a waste gas line 7 and introduced into an absorption tank 8 as a gas- treating apparatus to remove hydrogen chloride. A cooling apparatus 10 is inserted in the waste gas line 7 and the gas is cooled at a temperature lower than the boiling point of the organic solvent to separate and remove the solidified or liquefied organic component. A flow meter 11 is placed at the downstream of the cooling apparatus 10 and the flow rate of the waste gas is measured to judge the end point of the dechlorination treatment.