| 摘要 |
<p>PROBLEM TO BE SOLVED: To smoothly recover chlorine-free plastics and high-purity hydrogen chloride without causing any piping cloggings, etc., even for plastic wastes containing flexible polyvinyl chloride by dehydrochlorination of the subject plastic wastes at a specified temperature followed by conducting a deplasticizer treatment at another specified temperature. SOLUTION: First, plastic wastes containing polyvinyl chloride is dehydrochlorinated at 250-300 deg.C for a specified time using a relevant apparatus equipped with a twin interlocking-type screw (S)12a and then subjected to deplasticizer treatment at 300-370 deg.C for a specified time using a relevant apparatus directly coupled with the above apparatus and equipped with a twin interlocking screw S12b to remove e.g. >=90wt.% of the plasticizer contained, affording a plastic melt. Furthermore, according as necessary, the melt is compressed into a solid fuel, or further heated to 400-600 deg.C into oil. It is preferable that the gas generated in the dehydrochlorination be cooled to the condensation temperature of hydrogen chloride by a cooling tank 13a and then brought into contact with water in an absorption column 15 to recover the hydrogen chloride gas as hydrochloric acid.</p> |
