| 摘要 |
1367682 Polymer compositions; removal of volatile constituents FRENCH OIL MILL MACHINERY CO 25 Aug 1971 [4 Sept 1970] 39990/71 Heading B1B Polymer composition is freed from volatile constituents such as solvents by feeding it into the hopper 10 of a cylindrical screw press containing several screw members rotated on shaft 15, introducing a desolventizing agent (such as nitrogen, steam or water) into the compressed composition through an injector 25 in one of a series of lugs 23 surrounding collar 22, mechanically working the mixture by the notched flights of member 32 in section 30, whereby the mixture is heated, and then forcing it through annular orifice 42 between ring 40 and collar 35 into vent section 50 where volatile constituents are vaporized and flow through slits between parallel bars to housing 54 where the vapours are removed to a recovery system. The screw flight in section 50 has greater pitch and smaller body diameter than in the preceding sections. The polymer is then conveyed through three further sections 60, 70, 80 wherein addition of desolventizing agent, mechanical working, and venting of vapours respectively are effected similarly. The polymer is next conveyed through section 85 to rotating knife 95 at the end of the apparatus. The slices of desolventized polymer are fed into the inlet hopper 102 of a further screw press apparatus, provision being made for addition of a compounding substance, such as oil, through injector 107. Thermocouples 112 are placed at the annular orifices provided by rings 40 and 75; and these thermocouples may control motors 46 and 76 which adjust the longitudinal position of the rings and the opening or closing of the corresponding orifices. Liquid may be sprayed into housings 54 and 81 through spray heads 120 to prevent fine particles reaching the solvent recovery system. Solid compounding agents, such as carbon black or zinc oxide, and oil may be added to the polymer composition before desolventizing. A sulphur accelerator may be added to the desolventized polymer before it is discharged from the apparatus.
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