CN111442657A - A low pressure vacuum condenser - Google Patents

Abstract

A low-pressure vacuum condenser mainly includes a shell and a heat transfer tube bundle installed in the shell, a tube box installed at both ends of the shell, and a split-pass partition plate longitudinally arranged in the shell to divide the shell side of the tube bundle into an upper shell side and a lower part. The shell-side two-shell-side structure, the two ends of the split-pass separator are provided with through holes to connect the upper shell side and the lower shell side; the tube bundles in the upper shell side are arranged in square tubes, and the tube bundles are deflected by special-shaped folds. The flow rod is deflected; the tube bundles in the lower shell side are arranged in a regular triangle, and the tube bundles are deflected by a special-shaped baffle plate. The combination of the different tube bundle heat exchange tube arrangement and the tube bundle support method of the upper and lower shell sides of the present invention can not only reduce the drop of fluid resistance on the shell side of the heat exchanger, reduce the possibility of tube bundle vibration, but also take into account the heat transfer efficiency of the heat exchanger and improve the Equipment compactness.

Description

A low pressure vacuum condenser

technical field

The invention belongs to the technical field of low-pressure vacuum space wall condensation heat transfer, and in particular relates to a low-pressure vacuum condenser.

Background technique

At present, the low-pressure vacuum space wall condensation heat transfer technology mostly adopts a single-shell-pass structure or a single-external guide structure, and a shell-pass split-pass cooling technology. When the split-range condensation technology is used, the arrangement of the heat exchange tubes of the tube bundle is the same, and the baffles of the tube bundle are all baffle baffles. When the single-shell-side condensation technology is adopted, the shell-side non-condensable gas and the condensed liquid are not sufficiently separated, the condensation efficiency is low, and the non-condensable gas contains a lot of liquid. When using the existing split-range condensation technology, there are disadvantages such as large drop of equipment shell-side resistance and high vibration frequency of tube bundles.

SUMMARY OF THE INVENTION

The invention provides a low-pressure vacuum condenser, which takes into account the condensation resistance of the shell side fluid and the heat transfer efficiency, and at the same time reduces the vibration frequency of the tube bundle to a very low level.

The technical scheme adopted in the present invention is as follows:

A low-pressure vacuum condenser mainly includes a shell and a heat transfer tube bundle installed in the shell, a tube box installed at both ends of the shell, and a split-pass partition plate longitudinally arranged in the shell to divide the shell side of the tube bundle into an upper shell side and a lower part. The shell-side two-shell-side structure, the two ends of the split-pass separator are provided with through holes to connect the upper shell side and the lower shell side; the tube bundles in the upper shell side are arranged in square tubes, and the tube bundles are deflected by special-shaped folds. The flow rod is deflected; the tube bundles in the lower shell side are arranged in a regular triangle, and the tube bundles are deflected by a special-shaped baffle plate.

The middle part of the shell is provided with a middle outer guide tube coaxial with it, and the upper part of the shell is provided with a shell side fluid inlet; the middle part of the outer guide tube is coaxial with a middle part inner distribution tube, and the middle outer guide tube passes through the middle inner distribution tube. It is connected with the upper shell side; the middle outer guide tube and the middle inner distribution tube are divided into two independent parts by longitudinal partitions.

The special-shaped baffle rods are of a round-cut structure, and the baffle round rods are evenly distributed on the round-cut-shaped support ring vertically or horizontally, and the two are arranged at intervals.

The special-shaped baffle has a circular notch-shaped structure, the lower part of the baffle is not cut out in the pipe layout area, and the guide hole is opened in the heat exchange pipe bridge area in the pipe layout area.

The present invention is arranged horizontally, and the shell side adopts upper and lower shell side structures, wherein the tube bundle in the upper shell side adopts square pipe layout, the baffle mode of the tube bundle in the upper shell side adopts special-shaped baffle rod for baffle; the tube bundle in the lower shell side adopts triangular shape Pipe layout, the lower shell-side tube bundles are baffled by special-shaped baffles. The combination of different tube bundle heat exchange tube arrangements on the upper and lower shell sides and the tube bundle support method can not only reduce the fluid resistance drop on the shell side of the heat exchanger, reduce the possibility of tube bundle vibration, but also take into account the heat transfer efficiency of the heat exchanger and improve the compactness of the equipment. Spend.

Description of drawings

Fig. 1 is the structural representation of the present invention;

Fig. 2 is the shell side sectional schematic diagram of the present invention;

3 is a schematic cross-sectional view of the middle guide tube of the present invention;

4 is a schematic structural diagram of a special-shaped baffle rod of the present invention;

5 is a schematic structural diagram of another special-shaped baffle rod of the present invention;

6 is a schematic diagram of a special-shaped baffle of the present invention;

Reference number: front pipe box 1; shell 2; middle inner distribution cylinder 3; rear pipe box 4; support 5; pipe side exhaust port 6; special-shaped baffle rod 7; Flow tube 9; heat transfer tube bundle 10; tube-side fluid outlet 11; tube-side liquid outlet 12; special-shaped baffle 13; shell-side condensate outlet 14; tube-side fluid outlet 15; 17; shell side non-condensable gas outlet 18; heat exchange tube 19; circular missing support ring 20; baffle rod 21;

Detailed ways

The present invention and its beneficial effects will be further described below in conjunction with the accompanying drawings.

As shown in FIG. 1 , a low-pressure vacuum condenser includes a front tube box 1 , a shell 2 , a rear tube box 4 , a heat transfer tube bundle 10 and a support 5 . The front tube box 1 and the rear tube box 4 are sealedly connected with the tube sheets at both ends of the heat transfer tube bundle 10, and the shell 2 is sealed with the tube sheets at both ends of the heat transfer tube bundle 10, and the heat transfer tube bundle 10 is enclosed inside the shell 2; The support 5 supports the entire condenser, and the condenser is arranged horizontally. The heat transfer tube bundle of the present invention runs cold fluid inside the heat transfer tube bundle, and the heat fluid runs outside the heat transfer tube bundle, and the wall between the hot fluid and the cold fluid conducts heat.

As shown in FIG. 2 , the tube-side fluid flows into the front tube box 1 from the tube-side fluid inlet 15 , and then enters the tube bundle 10 from the front tube box 1 and then flows into the back tube box 4 after heat exchange with the wall of the shell-side fluid, and flows from the tube-side fluid outlet 11 Outflow, the front pipe box 1 is provided with a pipe-side exhaust port 6, and the rear pipe box 4 is provided with a pipe-side liquid outlet 12.

As shown in FIG. 3 , the split-pass baffle 17 longitudinally arranged in the casing 2 divides the shell side of the tube bundle into two shell-side structures, an upper shell side and a lower shell side. The hole connects the upper shell side and the lower shell side; the tube bundle in the upper shell side adopts square pipe layout, and the tube bundle is deflected by special-shaped baffle rods; the tube bundle in the lower shell side adopts equilateral triangle pipe layout , and the baffle of the tube bundle is baffled by special-shaped baffles.

The shell side of the present invention adopts the upper shell side and the lower shell side two shell side structures, so that the upper shell tube bundle is used to condense most of the low-pressure vacuum fluid of the shell side, so most of the fluid resistance is also concentrated here, and the vibration of the tube bundle is also more severe. The use of baffle rods in this area can effectively reduce fluid resistance and greatly reduce the possibility of tube bundle vibration. The upper shell-side tube bundle adopts square piping to meet the deflecting conditions of using baffle rods. At the same time, the square piping also reduces the fluid flow rate in this area, thereby reducing the fluid flow rate and the vibration frequency of the tube bundle.

The lower shell tube bundle is used for secondary condensation of a small part of the uncondensed shell-side fluid. The fluid velocity in this area is low and the fluid resistance is small. Therefore, the heat transfer area should be increased with as little space as possible. The lower shell side tube bundle adopts the regular triangular layout, and the lower shell side space is utilized as much as possible to increase the heat exchange area. The baffle mode of the lower shell-side tube bundle adopts special-shaped baffles, and the special-shaped baffles are arranged with large spacing, which reduces the difficulty of condenser manufacturing and takes into account pressure drop, heat transfer and vibration.

The upper shell tube bundle and the lower shell tube bundle adopt two different pipe layout methods and baffle support methods, which fully consider the characteristics of low-pressure vacuum gas condensation on the shell side, which not only meets its strict resistance drop requirements, but also fully considers condensation. The heat transfer efficiency of the device is improved, and the vibration frequency of the tube bundle is reduced to a very low level.

As shown in Figure 1, Figure 2, Figure 3, the middle part of the casing 2 is provided with a middle outer guide tube 9 coaxial with it, and the upper part is provided with a shell side fluid inlet 8; A distribution cylinder 3 in the middle is set, which is connected with the shell, and can also be a part of the shell, which is used for anti-flushing, diversion and uniform distribution of the shell-side fluid. The middle outer guide tube 9 is communicated with the upper shell side through the middle inner distribution tube 3; the middle outer guide tube 9 and the middle inner distribution tube 3 are divided into two independent parts by the longitudinal partition 16, and the longitudinal partition is located on the shell side. The split range is used to isolate the shell side inlet fluid and condensed liquid and non-condensable gas.

As shown in FIG. 3 , in order to ensure the technological performance of the condenser, a shell-side condensate outlet 14 is provided at the lower part of the middle outer guide tube 9 ; Cheng non-condensable gas outlet 18.

As shown in FIG. 4 and FIG. 5 , the special-shaped baffle rods have a round-cut structure, and the baffle round rods 21 are evenly distributed on the round-cut-shaped support ring 21 and are arranged at intervals. The circular-shaped support ring 21 corresponds to the cross-sectional shape of its upper shell side, and the baffle rods arranged at vertical or horizontal intervals form a group of four rods to clamp and support the heat exchange tube bundle and form a baffle.

The special-shaped baffle has a circular notch-shaped structure, the lower part of the baffle is not cut out in the pipe-laying area, and the guide hole 22 is opened in the heat-exchange pipe bridge area in the pipe-laying area. The lower edge of the special-shaped baffle corresponds to the shape of the shell side section. The lower part of the non-pipeline area is opened to drain the condensed liquid phase flow out of the shell side. The opening of the diversion hole in the pipe bridge area of the heat exchange tube in the pipe layout area has the effect of baffles to enhance heat transfer and diversion. At the same time, this type of fold The flow plate forms a full support for the lower shell side heat exchange tube, which greatly reduces the vibration of the lower shell side heat exchange tube.

In order to improve the heat transfer performance of the condenser, the heat transfer tubes 19 of the heat transfer tube bundle 10 are selected from threaded tubes or corrugated tubes.

As shown in FIG. 1 and FIG. 2 , an outer guide tube 9 is arranged in the middle of the housing 2 , and an inner distribution tube 3 is arranged inside the outer guide tube 9 . The shell-side fluid first enters the outer guide tube 9 through the shell-side fluid inlet 8, and the shell-side fluid first flows to the inner distribution tube 3. After blocking and anti-rush, it diffuses and decelerates in the outer guide tube 9, and the shell-side fluid is distributed in the third end of the tube. There are no openings in the part, and the distribution holes of the inner distribution cylinder 3 are evenly distributed into the tube bundle 20, and the heat exchange and condensation with the wall of the tube side fluid in the tube bundle 20 are carried out. The two ends of the dividing baffle 17 are opened into the second shell side, exchange heat with the tube side fluid wall in the second shell side and condense again, and the condensed non-condensable gas and condensate enter the outer guide tube in the middle of the shell again. 9. The non-condensable gas flows out of the equipment through the shell-side non-condensable gas outlet 18, and the condensate flows out of the equipment through the shell-side condensate outlet 14. The two shell-side fluids are separated within the outer guide cylinder 9 by the outer guide cylinder longitudinal partition 16 .

The upper and lower shell sides of the condenser adopt different piping methods and different baffle support methods, taking into account the pressure drop and heat transfer of the low-pressure vacuum fluid on the shell side, ensuring the full separation of non-condensable gas and condensed liquid, and at the same time as possible. It is possible to reduce the vibration frequency of the tube bundle, improve the heat transfer efficiency of the heat exchanger, and reduce the equipment cost and footprint.

Claims (6)

1. A low-pressure vacuum condenser, mainly comprising a shell and a heat transfer tube bundle installed in the shell, and a tube box installed at both ends of the shell, characterized in that the split-range partition ( 17) The shell side of the tube bundle is divided into two shell side structures, the upper side and the lower side. The two ends of the partition plate (17) are provided with through holes to connect the upper side and the lower side; the upper side is The inner tube bundle adopts square tube layout, and the tube bundle baffle mode adopts special-shaped baffle rod for baffle; the tube bundle in the lower shell side adopts equilateral triangle tube layout, and the tube bundle baffle mode adopts special-shaped baffle plate for baffle. 2 . The low-pressure vacuum condenser according to claim 1 , wherein a middle outer guide tube ( 9 ) coaxial with the shell ( 2 ) is provided in the middle of the shell ( 2 ), and a shell-side fluid is provided on the upper part. 3 . The inlet (8); the middle outer guide tube (9) is coaxially provided with a middle inner distribution tube (3), and the middle outer guide tube (9) is communicated with the upper shell side through the middle inner distribution tube (3); the middle outer guide The flow cylinder (9) and the middle inner distribution cylinder (3) are divided into two independent parts by the longitudinal partition plate (16). 3. A low-pressure vacuum condenser according to claim 2, characterized in that, a shell-side condensate outlet (14) is provided at the lower part of the middle outer guide tube (9); the longitudinal partition plate (14) A shell-side non-condensable gas outlet (18) is provided on the lower middle outer guide tube (9). 4. A low-pressure vacuum condenser according to claim 1, characterized in that, the special-shaped baffle rods are of a round-cut structure, and the baffle rods are evenly distributed on the round-cut support ring (21) vertically or horizontally. And the two are arranged at intervals. 5. A low-pressure vacuum condenser as claimed in claim 1, characterized in that: the special-shaped baffle is a circular notch-shaped structure, the lower part of the baffle is not cut in the area of pipe layout, and the heat exchange tube in the area of pipe layout A guide hole (22) is opened in the area of the pipe bridge. 6. A low-pressure vacuum condenser according to any one of claims 1 to 5, characterized in that: the heat exchange tubes (19) of the heat transfer tube bundle (10) are threaded pipes or corrugated pipes.

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