| 摘要 |
<p>PURPOSE: To obtain an extruder structure which is used in waste plastic recycling equipment, stably discharge hydrogen chloride gas through a vent hole, and is effectively protected from the internal corrosion and improved in durability by adopting a specific structure. CONSTITUTION: An extruder used has a charge port 2a for charging a waste plastic material, a discharge port 2b for discharging a primary melt of the material into a material mixing vessel, a transport mechanism 3 for transporting the material from the charge port 2a to the discharge port 2b, and a heating system 2c and 2d for the primary melting of the material. The extruder further has a vent channel 4 for connecting the space of a casing 2 heated by the heating systems 2c and 2d to the outside and a removing mechanism 5 for pushing the molten waste plastic comming into the vent channel 4 back to the inside of the casing 2. The inside surface of the low-temp. region of the casing on the side of the charge port 2a may be coated with a corrosion- resistant layer 6 made of a corrosion-resistant metal.</p> |
