Device for the ultrafiltration of a pressurized high-temperature liquid

Device for ultrafiltrating a pressurized high-temperature liquid the temperature and pressure of which are of the order of 300.degree. C. and 155.10.sup.5 Pa, respectively, having a first, pressure-resistant casing (1) containing an assembly of tubes (14) which form an ultrafiltration wall and which are fastened in a first tube plate (15), at one of their ends constituting an inlet end for a liquid to be filtered, and in a second tube plate (16), at their other end, and a chamber (28) delimited by said first tube plate (15) and said first casing (1), into which opens a pipe (6) supplying said liquid to be filtered, a filtrate discharge pipe (7) and a concentrate discharge pipe (8) likewise opening into said first casing (1), wherein said device comprises, inside said first casing (1), which consists of two separable parts (1a, 1b), a removable filtration assembly (10) consisting of

• (a) a second casing (11) located inside said first casing (1) so as to provide a continuous space (12) between its outer wall and the inner wall of said first casing (1) and on which said tube plates (15, 16) are fastened transversely so as to delimit, inside said second casing (11), a filtration chamber (24) which contains said tubes (14) and which is located between said two tube plates (15, 16) and a distribution chamber (25) downstream of said filtration chamber (24) in the direction of a tube outlet;
• (b) a first set of partitions (37) which are fastened inside said second casing (11) in said filtration chamber (24) and which delimit filtrate circulation compartments (24a, 24b, 24c, 24d, 24e, 24f) extending continuously in the axial direction of said tubes (14) between said two tube plates (15, 16), partitions of this first set having orifices (40) at one of their ends, so that each of said compartments (24a, 24b, 24c, 24d, 24e, 24f) communicates with two adjacent compartments at its end adjacent to said first plate (15) or at its end adjacent to said second plate (16), respectively, with the exception of one (24a) of said compartments which communicates with a single adjacent compartment (24b) and of another compartment (24f) which communicates with a single adjacent compartment (24e) and with a space (12) which is contained between said two casings and into which opens said filtrate discharge pipe (7);
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• (c) a second set of partitions (27) which are fastened on the inside of said concentrate distribution chamber (25) and which delimit compartments (25a, 25b, 25c) each communicating with the ends of a said assembly of tubes (14), an inflow chamber (28) for said liquid to be filtered likewise containing a partitioning (30) fastened to said first casing (1) which delimits compartments (28a, 28b, 28c, 28d) each communicating with the ends of a said assembly of tubes (14), said assemblies of tubes (14) communicating with said compartments of said distribution chamber (25) and with said compartments of said inflow chamber (28) respectively being selected so that a circulation with a constant flow of liquid is established in said tubes (14), in one direction or the other, between said inflow chamber (28) and said distribution chamber (25), one (28d) of said compartments of said inflow chamber (28) communicating with said concentrate discharge pipe (8).