CS214668B2 - Pipe heat exchanger for continuous extraction of solid substances by liquids - Google Patents

Abstract

1473821 Tubular heat exchangers VEREINIGTE ALUMINIUM-WERKE AG 24 Feb 1976 [2 April 1975] 07316/76 Heading F4S A tubular heat exchanger comprises a substantially U-shaped tube 1 conveying a first fluid in heat exchange with a second fluid flowing through another tube 2 extending through the tube 1 and consisting of a plurality of tube loops interconnected outside the tube 1 so as to form a continuous passageway for the second fluid. Preferably portions of the tube 2 cross each other either inside (e.g. at points A, B, Fig. 1) or outside (e.g. at points C, D, Fig. 2) the tube 1. The arrangement of the tube 2 may include return bends outside the tube 1 which, as shown in Fig. 3, may be enclosed within insulating material 3. Said bends may be joined by individual connections 4 (or alternatively by a common connector 5, Fig. 6) to the ends of the tube 2 projecting from the tube 1. Fig. 5 shows an arrangement comprising two of the tubes 1 placed end to end. In this case short detachable tubes are removable by means of joints 4 to enable the tube 2 to be cleaned. Water-jet cleaning means may be located within the tube 1. In use, a fluid medium such as a suspension of bauxite in sodium hydroxide passes through the tube 2 and is heated by a medium such as steam, a molten salt or a hot liquor flowing in the tube 1.

Description

The invention relates to a pipe heat exchanger for the continuous extraction of solids with liquids, in particular bauxite with sodium hydroxide solution, in which the outer tube guiding the heating means is constructed in a U-shape.

Such a pipe heat exchanger is known from the patent literature. However, it has the disadvantage that it needs a lot of space.

SUMMARY OF THE INVENTION It is an object of the invention to overcome this disadvantage and to provide a space-saving pipe heat exchanger in order not only to reduce the installation area, but also to reduce its investment and installation costs.

The object of the present invention is to provide a tube heat exchanger according to the invention, characterized in that within the outer tube of the heat exchanger, bundles of tubes are provided for guiding the fissile suspension several times in a circle, being crossed on the inner or outer sections of the outer tube of the heat exchanger. ..... ......

According to another embodiment of the invention, they are individual. . bundles of tubes for suspension, guided circularly inside. the outer tubes of the heat exchanger, led out of it, there are inverted and provided with an insulated part and then introduced again. - into the outer pipe of the heat exchanger, whereby at the points of their external maneuver, they are in favor of. heat exchange ineffective.

According to another embodiment of the invention, a second U-shaped outer heat exchanger tube is connected to the external " heat exchanger tube " as a practitioner for multiple slurry circulation by the two external heat exchanger tubes.

According to a further embodiment of the invention, the outer return insulated parts are removably connected via individual flanges or via a common collecting flange.

According to a further embodiment of the invention, the counterparts of the two outer heat exchanger tubes on the individual suspension bundles are detachably connected via individual flanges to the spacer, or via one common collecting flange.

According to a penultimate embodiment of the invention, the circularly guided suspension pipes pass in a collecting flange just between the bottom which is tightly enclosed in the outer heat exchanger pipe, the slurry pipes in one outer heat exchanger pipe being in contact with similar pipes in the flange connected to the other outer the heat exchanger tubes - and at their points of contact - are sealed to one another by means of sealing rings or other tubes for suspension.

According to a last embodiment of the invention, the suspension bundles are arranged inside the upper part of the outer tube of the heat exchanger, the free space in its lower part being adapted to. the location of a cleaning device, for example a hose with a high pressure water cleaning nozzle.

The new or higher effect achieved by the invention can be inferred from the following advantages:

The return insulated part of the suspension tube bundles can be easily removed for easy cleaning of the heat exchanger. The second return section contributes to the heat exchange, thereby reducing the installation area and reducing costs. The flange connection allows easy separation of the individual parts from each other. By inserting the interstices in the flange connection, another advantage arises in that the removal of the intermediate pieces can be easily cleaned by the outer heat exchanger tubes without having to be pulled apart. Finally, the space between the tube bundles for the suspension, which is sprayed by the released vapor vapor of the heating means, can be easily cleaned of any deposits.

The invention will now be described in more detail with reference to the drawings, in which: FIG. 1 illustrates an embodiment in which bundles of tubes are suspended in suspension within a U-shaped outer heat exchanger tube; FIG. FIG. 3 shows the possibility of connecting the outer heat exchanger pipe to the insulated part accommodating the return slurry bundles by means of individual flanges, FIG. 4 - a variation of this embodiment with a collecting flange, FIG. 5 - two opposed external heat exchanger tubes with individual flanges - on suspension bundles, including adapters, FIG. 6 shows another variation of this embodiment with the collecting flange, and FIG. 7 shows a section through the collecting flange.

All of the drawings show the U-shaped outer tube 1 of the heat exchanger, which is filled with heating means, in particular released vapor vapor, or also with a salt melt or decomposition lye, which heats the suspension several times circulating in the tubes 2.

According to FIG. 1, the pipes 2 cross. for suspension in - the outer pipe part - 1 of the heat exchanger, bent in a U-shape, for example - on sections A, B.

According to FIG. 2, this crossing occurs outside the heat exchanger pipe 1, for example at sections C, D.

FIG. 3 shows the insulated part 3 comprising the return conduits 2 for the suspension as well as the connection of the bundles of tubes 2 by means of individual flanges 4.

According to FIG. 4, the tube bundles 2 for suspension in the heat exchanger outer pipe 1 are connected to the tube bundles 2 in the insulated part 3 by means of a collecting flange S.

Also shown in FIG. 5 are the individual flanges 4 for connecting the bundles of slurry tubes 2 with the two heat exchanger outer tubes 1 connected together with the intermediate pieces.

Giant. 6 shows the collecting flanges 5 in the variation of FIG. 5.

Giant. 7 shows a collecting flange for example for the embodiment of FIG. 6. The slip tubes 2 guided in the ring are routed tightly in the intermediate chamber 6, which is closed tightly in the outer heat exchanger tube 1 via an outer flange 7. The tubes 2 are in contact with similar tubes 2 in a flange-connected outer heat exchanger tube 1 and at their points of contact, they are sealed to each other by means of the sealing rings 8 and / or the second suspension tubes 2.

Claims (7)

SUBJECT Tube heat exchanger for the continuous extraction of solids with liquids, in particular bauxite with sodium hydroxide, in which the outer pipe guiding the heating means is U-shaped, characterized in that tube bundles (2) are arranged inside the outer heat exchanger pipe (1). ) for guiding the fissile suspension several times in a circle, crossing on the inner sections (A, Bj or outer sections (C, D) of the outer tube (1) of the heat exchanger. Tube heat exchanger according to claim 1, characterized in that the individual suspension bundles (2) are guided in a circular manner inside the outer heat exchanger tube (1), are led out of it, inverted there and provided with an insulated part (3) and then they are in turn introduced into the outer tube (1) of the heat exchanger and are ineffective at the locations of their external heat exchanger bridges. Tubular heat exchanger according to claim 1, characterized in that it is connected to the external heat exchanger tube (1) as a counterpart. a double U-shaped second heat exchanger outer tube (1) designed for several slurry circulation by the two heat exchanger outer tubes (1) connected to each other. Pipe heat exchanger according to claim 2, characterized in that the outer return insulated parts (3) are connected via individual sleeves (4) or one common collecting flange (5). Tube heat exchanger according to claim 3, characterized in that the counterparts of the two outer tubes (1) of the heat exchanger are removably connected to the individual suspension bundles (2) via the individual flanges (4) to the spacer or via one common collecting flange. (5). 6. Pipe heat exchanger according to points 4 a 5, characterized in that the circularly guided suspension tubes (2) pass in the collecting flange (5) tightly through the intermediate chamber (6) which is tightly enclosed in the outer tube (1) of the heat exchanger, the tubes (2) from one outer tube (2). 1) the heat exchanger is in contact with similar pipes (2) in the flange-connected second outer tube · (1) of the heat exchanger and are sealed at their points of contact by means of sealing rings (8) or second pipes (2) for suspension. 7. Pipe heat exchanger according to items 1 to 6, characterized in that the bundles of tubes (2) for suspension. They are arranged inside the upper part of the outer tube (1) of the heat exchanger, the free space in the lower part of which is adapted to receive a cleaning device, for example a hose with a high pressure water cleaning nozzle.