Extraction of polymer granule stream and draining of carrier liquid flow takes place under inert gas blanket in fluid-sealed containment of plant transferring process heat for energy efficiency

摘要

Extraction of polymer granule stream and draining of carrier liquid flow takes place under inert gas blanket in fluid-sealed containment of plant transferring process heat. Granule-fluid mixture from the extractor (10) flows through a reflexive concentric pipe assembly (11) with vent line (12) to the top of the extractor, upper spaces being inert gas-blanketed. The mixture flows down (11) then up (14) to an upper inversion. The effective fluid head between the height (Hst) and the upper inversion, corresponds to the gas pressure in the extractor. The conveying fluid first enters a downward pipe (2) in a similar reflexive concentric pipe assembly, with upper connection (3) to the gas in the extractor, which fills the upper spaces. The two reflexive concentric pipe systems perform granule-conveying, separation and de-gasification functions, and will be recognized in addition, as inert gas seals or liquid lutes; they are described in further detail. Degasification takes place in the outer pipe (5), to the space above the overflow (6). Granule-fluid mixture from the extractor outlet enters the side of the sealed section (16) in which its available heat is given up in counterflow to the colder, descending extraction fluid. Then in the perforated section (17) above, extraction fluid which has been heated, yet is still cold in relation to process extraction fluid, flows down in the double-walled section (15), from where it is led into the process. Preferred features of the process equipment are detailed, in accordance with the foregoing principles; variants are also described and illustrated. Critical vertical dimensions are quantified.