| 摘要 |
<p>PROBLEM TO BE SOLVED: To recover HCL gas generated in pyrolysis as hydrochloric acid finally disposable easily, to suppress the generation of needle crystal such as phthalic anhydride and to prevent anchoring of residue and blocking with wax. SOLUTION: This heat treatment comprises treating steps as followes; steam is introduced so as to hydrolyse and to compulsively add OH group to decomposition products in order to obtain an alcohol in decomposition of plasticizer contained in a vinyl chloride resin, concurrently, HCL gas generated in decomposition of the vinyl chloride resin is absorbed in water and recovered as hydrochloric acid, therefore, the generation of an organochlorine compound having CL group originated in the plasticizer is prevented and the resultant alcohol dissolves needle crystal such as phthalic anhydride generated by decomposition of the plasticizer and the generation of crystal product such as phthalic anhydride is prevented.</p> |
