JPS5931667B2 - Kouonetsukoukanki - Google Patents

Description

[Detailed description of the invention] The present invention relates to improvements in ultra-high temperature heat exchangers.

The purpose of the present invention is to solve various technical problems that occur in ultra-high temperature heat exchangers, such as uneven material deterioration, thermal expansion, and thermal stress caused by operation in ultra-high temperature ranges. To resolve difficulties as and rationally as possible. The aim is therefore to provide a heat exchanger with a structure whose service life is extended as much as possible. The first feature of the heat exchanger improved by the present invention is that the primary high temperature gas is introduced to the lower part of the heat exchange chamber through the inner tube. The next feature of the present invention is that a plurality of secondary gas inlet nozzles are installed in the head of the heat exchanger, a tube sheet is attached to the secondary gas inlet nozzles, and a plurality of The structure is such that heat exchanger tubes are installed. Another feature of the present invention is that an inner wall tube is lined in the inner shell and forms a chamber (heat exchange chamber) that accommodates the primary high temperature gas and performs heat exchange with the secondary gas flowing inside the heat transfer tube. A high-temperature tube plate is attached to the lower end of the inner wall tube, and the upper end of this inner wall tube is directly connected to the pressure tube at a position where the temperature of the primary gas has sufficiently decreased, and the lower end is connected to the free end. It has a so-called suspended structure.

In addition to the above-mentioned main features, the improved heat exchanger according to the present invention has many benefits and effects in extending the service life of the heat exchanger due to various detailed improvements.

Other objects, features, etc. of the present invention will be further understood from the following description of the embodiments. In FIG. 1, an inlet nozzle 1 for introducing first-order high temperature gas of about 1000° C. is directly connected to an inner tube 2 at the head of the heat exchanger.

The inner cylindrical tube 2 is originally located at the center of the heat transfer tube group 3 formed into a coil shape (see Fig. 3), and is used for the purpose of preventing a short circuit phenomenon of the primary high temperature gas. However, in the present invention, the primary gas is caused to flow inside the inner cylinder pipe 2 with the intention of combining functions.
It is configured to flow into the heat exchange chamber 4 from the outlet 2a at the lower end thereof. The inner cylinder tube 2 is suspended by a support plate 11 attached to the inner shell 15. The first-order high-temperature gas exchanges heat with the fluid in the heat exchanger tube while rising through the heat exchange chamber 4, and its temperature gradually drops, and is discharged from the outlet nozzle 5 at the upper part of the heat exchanger at about 400° C., for example. The inner surface of the inner cylindrical tube 2 is lined with a heat insulating material 6 for the purpose of preventing the temperature of the inner cylindrical tube material from rising and preventing heat exchange between the inside and outside of the primary gas through the wall of the inner cylindrical tube 2. There is. On the other hand, the secondary low-temperature gas is introduced into a cooling passage 10 formed by a pressure pipe 8 and an inner shell 9 concentric with the pressure pipe 8 through an inlet nozzle 7 having a double pipe structure, and is caused to ascend through this passage.

As a result, the temperature of the pressure pipe 8 as a pressure chamber is maintained at around 300° C., for example. The low temperature secondary gas is temporarily taken out of the vessel through the outlet nozzle 12 provided at the upper end of the cooling passage 10.

Then, it is guided again to the inlet nozzle 13 at the head of the heat exchanger via piping (not shown). This inlet nozzle 13
As shown in the figure, a plurality of heat exchangers are provided in a concentric arrangement in the head of the heat exchanger. The reason for this is that the tube plate 14 is attached to the inlet nozzle 13 through the passage described below.
Using this tube plate 14, the required number (for example, about 4
Since the heat exchanger tubes 3 (00 pieces) are arranged closely, a predetermined number of inlet nozzles 13 are provided as described above in order to obtain a tube plate area necessary for arranging the heat exchanger tubes. As already mentioned, the heat exchanger tube group 3 of this heat exchanger is formed into a coil shape between upper and lower tube sheets, and is laminated in multiple layers in a centripetal arrangement (see Fig. 3). ).

The heat exchanger tube group 3 formed into a coil shape and laminated in multiple layers is supported by a tube support plate 16 installed in the radial direction.
The tubes are properly positioned and the spacing between the tubes is maintained. Next, the lower high-temperature tube plate 1r has a circular heat exchange chamber 1.
4 is attached to the lower end of a long inner wall tube 18 with an inverted conical support wall 19 interposed therebetween. The inner wall tube 18 is made of a material such as a super heat-resistant alloy with excellent heat resistance, such as Hastelloy IX, and is located inside the heat insulating material 20 lined in the inner shell 9. The high-temperature tube sheet 17 and the support wall 19 integrally joined thereto are configured so that both surfaces thereof are exposed to high vortex gas of about 1000° C., and the shape of the heat insulating material 20 is such that the inner wall tube 18 A gap 21 is left that allows for free downward thermal expansion. The upper end of the inner wall tube 18 is directly connected airtightly to the pressure tube 22 at a position where the primary gas, whose temperature has decreased while ascending through the heat exchange chamber 4, is in a mixed atmosphere without thermal interference to the pressure tube. There is. The high temperature secondary gas leaving the heat transfer tube 3 is transferred to the fluid chamber 2.
r, and is sent from the outlet nozzle 23 to a predetermined location.

The upper part of the heat exchanger, which is filled with the primary gas whose temperature has been lowered by heat exchange, also constitutes a cooling passage 24 with the pressure pipe 22 and the inner shell 15 arranged concentrically therewith.

The low-temperature primary gas that has exited the outlet nozzle 5 and passed through the circulator is introduced into the cooling passage 24 from the inlet nozzle 25, and the temperature rise in the pressure pipe 22 is suppressed. cooling passage 24
The low-temperature primary gas leaves the outlet nozzle 26, which forms a concentric double pipe with the already mentioned inlet nozzle 1 for the high-temperature primary gas, and returns to the heat source. Next, let's talk a little about how to assemble this heat exchanger.

The structure of this heat exchanger can be roughly divided into two parts.

In other words, there is a primary side lower pressure boundary where the inner shell 9 is lined with a heat insulating material 20, and a 2 where the inner shell is not lined with a heat insulating material.
This is the next (upper) pressure boundary. The inner shell tube 2 and the inner wall tube 18, and thus the lower hot tube sheet 1r, are subject to the secondary (upper) pressure boundary. The upper and lower parts are individually assembled and finally assembled by inserting the inner wall tube 18 into the heat insulating material 20. Both flanges 28 and 29 are provided on each pressure pipe.
It is completed by bolting the parts together. One of the main features of the present invention is that the primary high temperature gas is guided from the outlet 2a to the heat exchange chamber 4, so that the heat exchanger tube support plate 16 and the heat exchanger tubes 3 supported thereon are in the same muddy atmosphere. As a result, the heat exchanger tube support plate 16, the heat exchanger tubes 3, and the inner wall tubes 18 have the same amount of thermal expansion, and the joints between the tube sheet 14 and the heat exchanger tubes 3 and between the high temperature tube sheet 17 and the heat exchanger tubes 3 is at the point where no stress due to differential thermal expansion is applied.

Similarly, since the inner wall tube 18 and the tube sheet support wall 19 are in contact with the primary gas of uniform temperature, another feature is that the same thermal expansion as that of the heat transfer tube 3 occurs without any restriction. Therefore, with this structure, no thermal stress is generated in the heat exchanger tubes 3. Furthermore, since both the front and back surfaces of the high-temperature tube plate 17 come into contact with gas having the same vorticity, the generation of thermal stress is minimal. Thus, according to the present invention, the adverse effects of thermal stress on the above-mentioned members at extremely high temperatures are completely eliminated, so a heat exchanger with an extremely long life is provided.

[Brief explanation of drawings]

FIG. 1 is a vertical sectional view of a heat exchanger according to the present invention, and FIGS. 2 and 3 are sectional views 2-2 and 3-3 of FIG. DESCRIPTION OF SYMBOLS 1... Inlet nozzle, 2... Inner cylinder pipe, 2a... Outlet, 3... Heat exchanger tube group, 4... Heat exchange chamber, 5... Outlet nozzle 6... Heat insulating material , 7... inlet nozzle, 8...
・Pressure pipe, 9...Inner shell, 10...Conditioning passage, 11.
...Support plate, 12...Outlet nozzle, 13...
Inlet nozzle 14...tube plate, 15...inner shell, 16.
...Pipe support plate, 1r...High temperature tube plate, 18...
Flesh wall tube, 19... inverted conical support wall, 20... new thermal material,
21... Gap, 22... Pressure pipe, 23... Outlet nozzle, 24... Cooling passage, 25... Inlet nozzle, 2
6...Outlet nozzle, 2r...Fluid chamber, 28...Flange, 29...Flange.

Claims (1)

[Claims] 1 Insert the inner tube 9 into the pressure tube 8 and provide an annular gap between the inner circumferential surface of the pressure tube 8 and the outer circumferential surface of the inner tube 9 to form the cooling passage 10.
The primary side (lower side) pressure boundary part is formed by forming a heat insulating material 20 on the inner peripheral surface of the inner pipe 9, and the inner pipe 15 is inserted into the pressure pipe 22, and the inner peripheral surface of the pressure pipe 22 and the inner A secondary side (upper) pressure boundary section is formed by providing an annular gap between the outer peripheral surface of the pipe 15 to form a cooling passage 24, and an upper end is formed on the inner periphery of the pressure pipe 22 of the secondary side pressure boundary. An inner wall pipe 18 that is fixed and vertically installed along the inner surface of the cross-sectional material 20 of the primary side pressure boundary, and a pressure pipe 22 and the inner pipe 1 of the secondary side pressure boundary.
A plurality of secondary fluid inlet nozzles 1 are provided to penetrate through 5.
3, the secondary fluid inlet nozzle 13 and the inner wall tube 18
A tube sheet 14 and a high-temperature tube sheet 17 are provided at the lower ends of the tube sheet 14 and a high temperature tube sheet 17 respectively, and a heat exchanger tube group 3 is provided passing through these tube sheets.
An inner cylindrical tube 2 inserted into the center of the tube and having an outlet 2a at the lower end.
, a primary fluid inlet nozzle 1 provided at the secondary side pressure boundary and communicating with the inner cylindrical pipe 2, a primary fluid inlet nozzle 25 and a pressure pipe 2 passing through the pressure pipe 22 and communicating with the cooling passage 24.
2, a primary fluid outlet nozzle 5 provided through the inner pipe 15, a secondary fluid outlet nozzle 23 provided at the primary side pressure boundary, and a cooling passage 10 with an annular gap provided around the outer periphery of the secondary fluid outlet nozzle 23. a secondary fluid inlet nozzle 7 which communicates with a secondary fluid outlet nozzle 12 via a high temperature heat exchanger.