| 摘要 |
1,074,619. Condensation of vapours. MONSANTO CO. June 1, 1965 [June 1, 1964], No. 23260/65. Heading BIB. Excess ethylene glycol is recovered from the polymerized product of the reaction between the glycol and dimethyl terephthalate by directing the vapour from he polymerization vessel through pipe 11 into contact with a drum 12 rotating on a horizontal axis in chamber 10 which contains a pool 14 of cool liquid glycol. The distance between the discharge end 29 of pipe 11 and the drum 12 is 3 to 76 mm. Non- condensed vapour leaves chamber 10 through outlet 15, which is connected to a source of vacuum. Liquid glycol containing solid esters in suspension is removed from the rotating drum by scraper 16, and the suspension is withdrawn from chamber 10 through outlet 17 to a filter. The filtered glycol is cooled to about 40‹C., and some of it is withdrawn from the system while the remainder is recycled to the drum through inlet 13. Inlet pipe 11 is provided with a heating-jacket 20 in order to maintain the temperature of the vapour at 265‹ to 300‹C. The drum is rotated at 10 to 40 r.p.m.; and it may be internally heated, if desired. |
