CN111623653B - Series PCHE heat exchanger suitable for cylindrical arrangement and heat exchange method - Google Patents

Abstract

The present invention discloses a series PCHE heat exchanger suitable for cylinder arrangement and a heat exchange method. The heat exchanger consists of a hollow cylinder, which is connected as a whole by vacuum diffusion welding from front to back and is composed of a front cover plate, a plurality of hot medium plates, a cold medium plate and a rear cover arranged in the hollow cylinder. The microchannels on the hot medium plates and the cold medium plates are formed by etching. The heat exchanger uses the cylindrical shape as a space limitation and a supercritical CO2 power generation system as an application background. It integrates the functions of a regenerator and a precooler in the supercritical CO2 power generation system, and all external interfaces are arranged on the front cover plate. The heat exchanger effectively utilizes the given space to the maximum extent.

Description

A series PCHE heat exchanger suitable for cylinder arrangement and heat exchange method

Technical Field

The invention belongs to the technical field of heat exchange devices and relates to a series PCHE heat exchanger suitable for cylinder arrangement and a heat exchange method.

Background Art

Printed circuit heat exchanger (PCHE) belongs to the category of microchannel plate heat exchanger. PCHE has the advantages of compact structure, high temperature resistance, high pressure resistance, safety and reliability, and is widely used in refrigeration and air conditioning, petroleum and natural gas, nuclear industry, chemical industry, power industry and other fields.

Currently, most common PCHE heat exchangers are square, and the inlet and outlet pipes are distributed on four different sides of the heat exchanger. In this way, the inlet and outlet pipes of the heat exchanger are relatively scattered, occupying a large space. In addition, generally speaking, a PCHE heat exchanger only realizes the heat exchanger function of one circuit. Multiple heat exchanges in several circuits require multiple independent PCHE heat exchangers to achieve this. In this way, there will be more heat exchanger inlet and outlet connecting pipes, which will occupy more space.

In some special applications, such as ships and offshore platforms, due to the small space and special requirements for the layout shape, the space utilization rate of ordinary square independent PCHE heat exchangers is too low, and specially designed heat exchangers are required to meet special needs.

Summary of the invention

In order to solve the problems existing in the above-mentioned prior art, the purpose of the present invention is to provide a compact series PCHE heat exchanger and a heat exchange method suitable for cylindrical layout requirements. The heat exchanger takes cylindrical layout as the spatial layout requirement and takes supercritical CO2 cycle power generation system as the application background. The characteristic of the heat exchanger is that the regenerator and the precooler are combined into one, which is realized by one heat exchanger, and all external interfaces of the heat exchanger are on the front cover of the heat exchanger, and there are no inlets and outlets on other sides of the heat exchanger.

To achieve the above purpose, the technical solution adopted by the present invention is as follows:

A series PCHE heat exchanger suitable for cylindrical arrangement, the heat exchanger can realize the functions of a regenerator and a precooler in a supercritical CO2 power generation system, and is cylindrical in shape as a whole, including a front cover plate A, a plurality of hot medium plates B, a plurality of cold medium plates C, and a rear cover plate D which are connected as a whole by vacuum diffusion welding from front to back, the hot medium plates B and the cold medium plates C are plates with microchannels etched on the metal plate surface, and the hot medium plates B and the cold medium plates C are distributed at intervals;

The same positions of the hot medium plate B and the cold medium plate C are all provided with a CO2 hot side inlet 1, a CO2 cold side outlet 2, a CO2 cold side outlet return port 3, a cooling water inlet 4, a CO2 hot side outlet return port 6, a CO2 hot side outlet 7, a CO2 cold side inlet 8, a cooling water outlet return port 9 and a cooling water outlet 10; the same positions of the hot medium plate B and the cold medium plate C on the front cover plate A are provided with a CO2 hot side inlet 1, a CO2 cold side outlet return port 3, a cooling water inlet 4, a CO2 hot side outlet return port 6, a CO2 cold side inlet 8 and a cooling water outlet return port 9; the same positions of the hot medium plate B and the cold medium plate C on the rear cover plate D are provided with a CO2 cold side outlet 2, a CO2 cold side outlet return port 3, a CO2 hot side outlet return port 6, a CO2 hot side outlet 7, a cooling water outlet return port 9 and a cooling water outlet 10;

The heat exchanger has a total of six external interfaces, all of which are arranged on one side of the front cover A. The CO2 hot side inlet 1 on the front cover A is connected to the CO2 hot side inlet pipe outside the heat exchanger, the CO2 cold side outlet return port 3 is connected to the external CO2 cold side outlet pipe, the cooling water inlet 4 is connected to the external cooling water inlet pipe, the CO2 hot side outlet return port 6 is connected to the external CO2 hot side outlet pipe, the CO2 cold side inlet 8 is connected to the external CO2 cold side inlet pipe, and the cooling water outlet return port 9 is connected to the external cooling water outlet pipe.

Three deflector heads E are welded on the rear cover plate D, and the three deflector heads E respectively connect the CO2 hot side outlet 7 with the CO2 hot side outlet return port 6, connect the cooling water outlet 10 with the cooling water outlet return port 9, and connect the CO2 cold side outlet 2 with the CO2 cold side outlet return port 3.

The front cover plate A, the plurality of hot medium plates B, the plurality of cold medium plates C and the rear cover plate D are all provided with heat insulation and weight reduction holes 5 at the same position along the axial direction.

The heat exchange method of the PCHE heat exchanger in series with a cylindrical arrangement is described, wherein the high-temperature CO2 flows into the heat exchanger from the CO2 hot side inlet 1 of the front cover plate A, is dispersed in each heat medium plate B, flows along the microchannel in the heat medium plate B, and then flows out from the CO2 hot side outlet 7 of the heat medium plate B, flows to the baffle head E of the rear cover plate D, and is turned in the baffle head E to flow from the CO2 hot side outlet return port 6 from the back to the front to the CO2 hot side outlet external pipeline connected to the front cover plate A;

Low-temperature CO2 flows into the heat exchanger from the CO2 cold side inlet 8 of the front cover plate A, is dispersed in the CO2 channels of each cold medium plate C, flows along the microchannels in the cold medium plate C, and then flows out from the CO2 cold side outlet 2 of the cold medium plate C, flows to the baffle head E of the rear cover plate D, turns in the baffle head E and flows from the CO2 cold side outlet return port 3 from back to front to the CO2 cold side outlet external pipeline connected to the front cover plate A;

The cooling water flows into the heat exchanger from the cooling water inlet 4 of the front cover plate A, is dispersed in the microchannels of each cold medium plate C, flows along the microchannels in the cold medium plate C, and then flows out from the cooling water side outlet 10 of the cold medium plate micro, flows to the deflector head E of the rear cover plate D, turns in the deflector head E, and flows from the cooling water outlet return port 9 from back to front to the cooling water outlet external pipeline connected to the front cover plate A, thereby achieving heat exchange.

The present invention has the following beneficial effects:

(1) Combining the regenerator and the precooler into one: The present invention integrates the two heat exchangers, the regenerator and the precooler, into one cylindrical heat exchanger. The CO2 hot side outlet of the regenerator and the CO2 side inlet of the precooler are the heat medium plate channels of the heat exchanger, and there is no separate inlet and outlet. Such an arrangement makes maximum use of the cylindrical space and meets the special requirements of the cylindrical space arrangement.

(2) All inlets and outlets of the heat exchanger are gathered on the front cover of the heat exchanger. There are no inlets and outlets on the cylindrical side and the rear cover. Therefore, no pipes are required around the heat exchanger, which saves space to the maximum extent.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a schematic diagram of a supercritical CO2 power generation system.

Among them, 1-1 is the generator, 2-1 is the compressor, 3-1 is the turbine, 4-1 is the regenerator, 5-1 is the precooler, 6-1 is the cooling water outlet pipe, 7-1 is the CO2 cold side outlet pipe, 8-1 is the CO2 hot side inlet pipe, 9-1 is the CO2 cold side inlet pipe, 10-1 is the CO2 hot side outlet pipe, and 11-1 is the cooling water inlet pipe.

Figure 2 is a schematic diagram of the heat exchanger plate structure.

Among them, A is a hollow cylinder, B is a front cover, C is a hot medium plate, D is a cold medium plate, and E is a rear cover.

FIG3 is a schematic diagram of the cold medium plate channel and inlet and outlet.

Figure 4 is a schematic diagram of the heat medium plate channel. Figure 5 is a schematic diagram of the rear cover plate and the baffle head.

Figure 6 is a schematic diagram of the front cover pipe opening.

Figure 7 is a schematic diagram of the rear cover pipe opening.

Among them, 1 is the CO2 hot side inlet, 2 is the CO2 cold side outlet, 3 is the CO2 cold side outlet return port, 4 is the cooling water inlet, 5 is the insulation and weight reduction hole, 6 is the CO2 hot side outlet return port, 7 is the CO2 hot side outlet, 8 is the CO2 cold side inlet, 9 is the cooling water outlet return port, and 10 is the cooling water outlet.

DETAILED DESCRIPTION

The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

As shown in the schematic diagram 1 of the supercritical CO2 system, the heat exchanger of the present invention can realize the functions of the regenerator 4-1 and the precooler 5-1 in the supercritical CO2 power generation system. In the system, the CO2 on the hot side of the regenerator 4-1 comes from the exhaust gas of the turbine 3-1, and is discharged from the hot side of the precooler after releasing heat through the regenerator 4-1 and the precooler 5-1, and enters the compressor 2-1. The CO2 at the outlet of the compressor 2-1 enters the cold side inlet of the regenerator 4-1, and is discharged from the cold side outlet after absorbing heat. The water side inlet and outlet of the precooler 5-1 are connected to the cooling water supply and drainage outside the system.

As shown in FIG2 , the present invention is a series PCHE heat exchanger suitable for cylindrical arrangement, which is cylindrical as a whole and includes a front cover plate A, a plurality of hot medium plates B, a plurality of cold medium plates C and a rear cover plate D which are connected as a whole by vacuum diffusion welding from front to back. The hot medium plates B and the cold medium plates C are both plates with microchannels etched on the metal plate surface, and the hot medium plates B and the cold medium plates C are distributed at intervals.

As shown in Figures 3 and 4, the same positions of the hot medium plate B and the cold medium plate C are distributed with a CO2 hot side inlet 1, a CO2 cold side outlet 2, a CO2 cold side outlet return port 3, a cooling water inlet 4, a CO2 hot side outlet return port 6, a CO2 hot side outlet 7, a CO2 cold side inlet 8, a cooling water outlet return port 9 and a cooling water outlet 10.

As shown in FIG6 , at the same position on the front cover plate A as the hot medium plate B and the cold medium plate C, there are a CO2 hot side inlet 1, a CO2 cold side outlet return port 3, a cooling water inlet 4, a CO2 hot side outlet return port 6, a CO2 cold side inlet 8 and a cooling water outlet return port 9.

As shown in FIG7 , at the same positions on the rear cover plate D as the hot medium plate B and the cold medium plate C, there are a CO2 cold side outlet 2, a CO2 cold side outlet return port 3, a CO2 hot side outlet return port 6, a CO2 hot side outlet 7, a cooling water outlet return port 9 and a cooling water outlet 10.

The heat exchanger has a total of six external interfaces, as shown in Figures 2 and 6, all of which are arranged on one side of the front cover A. The CO2 hot side inlet 1 on the front cover A is connected to the CO2 hot side inlet pipe outside the heat exchanger, the CO2 cold side outlet return port 3 is connected to the external CO2 cold side outlet pipe, the cooling water inlet 4 is connected to the external cooling water inlet pipe, the CO2 hot side outlet return port 6 is connected to the external CO2 hot side outlet pipe, the CO2 cold side inlet 8 is connected to the external CO2 cold side inlet pipe, and the cooling water outlet return port 9 is connected to the external cooling water outlet pipe.

As shown in Figures 5 and 7, as a preferred embodiment of the present invention, three deflection heads E are welded on the rear cover plate D, and the three deflection heads E respectively connect the CO2 hot side outlet 7 with the CO2 hot side outlet return port 6, connect the cooling water outlet 10 with the cooling water outlet return port 9, and connect the CO2 cold side outlet 2 with the CO2 cold side outlet return port 3.

As a preferred embodiment of the present invention, the front cover plate A, the plurality of hot medium plates B, the plurality of cold medium plates C and the rear cover plate D are all provided with heat insulation and weight reduction holes 5 at the same position along the axial direction.

As shown in FIG2 , the present invention discloses a heat exchange method for a series PCHE heat exchanger suitable for a cylindrical arrangement, wherein high-temperature CO2 flows into the heat exchanger from the CO2 hot side inlet 1 of the front cover plate A, is dispersed in each heat medium plate B, flows along the microchannel in the heat medium plate B, and then flows out from the CO2 hot side outlet 7 of the heat medium plate B, flows to the deflection head E of the rear cover plate D, deflects in the deflection head E, flows from the CO2 hot side outlet return port 6 from back to front to the CO2 hot side outlet external pipeline connected to the front cover plate A; low-temperature CO2 flows into the heat exchanger from the CO2 cold side inlet 8 of the front cover plate A, is dispersed in the CO2 channels of each cold medium plate C, flows along the microchannel in the cold medium plate C, and ... to the CO2 hot side outlet external pipeline connected to the front cover plate A. The cooling water flows through the microchannels, and then flows out from the CO2 cold side outlet 2 of the cold medium plate C, flows to the baffle head E of the rear cover plate D, turns in the baffle head E to flow from the CO2 cold side outlet return port 3 from back to front to the CO2 cold side outlet external pipeline connected to the front cover plate A; the cooling water flows into the heat exchanger from the cooling water inlet 4 of the front cover plate A, is dispersed in the microchannels of each cold medium plate C, flows along the microchannels in the cold medium plate C, and then flows out from the cooling water side outlet 10 of the cold medium plate micro, flows to the baffle head E of the rear cover plate D, turns in the baffle head E to flow from the cooling water outlet return port 9 from back to front to the cooling water outlet external pipeline connected to the front cover plate A, and heat exchange is realized.

The above detailed description is only a preferred embodiment of the present invention. If the supply direction of the external pipeline of the heat exchanger is changed, for example, the cooling water inlet and outlet are at the rear of the heat exchanger, it is only necessary to adjust the position of the head on the front and rear cover plates and the position of the connecting pipe. This cannot limit the scope of the present invention. That is, all equivalent changes and modifications made according to the scope of the patent application of the present invention should fall within the scope covered by the patent of the present invention.

Claims (2)

1. The series PCHE heat exchanger is suitable for cylindrical arrangement, and is characterized in that the heat exchanger can realize the functions of a heat regenerator and a precooler in a supercritical CO2 power generation system, is cylindrical as a whole, and comprises a front cover plate (A), a plurality of heat medium plates (B), a plurality of cold medium plates (C) and a rear cover plate (D) which are connected into a whole sequentially from front to back through vacuum diffusion welding, wherein the heat medium plates (B) and the cold medium plates (C) are plates with micro channels etched on a metal plate surface, and the heat medium plates (B) and the cold medium plates (C) are distributed at intervals;

The same positions of the heat medium sheet (B) and the cold medium sheet (C) are respectively provided with a CO2 hot side inlet (1), a CO2 cold side outlet (2), a CO2 cold side outlet return port (3), a cooling water inlet (4), a CO2 hot side outlet return port (6), a CO2 hot side outlet (7), a CO2 cold side inlet (8), a cooling water outlet return port (9) and a cooling water outlet (10); the front cover plate (A) is provided with a CO2 hot side inlet (1), a CO2 cold side outlet return port (3), a cooling water inlet (4), a CO2 hot side outlet return port (6), a CO2 cold side inlet (8) and a cooling water outlet return port (9) at the same position as the hot medium plate (B) and the cold medium plate (C); the back cover plate (D) is provided with a CO2 cold side outlet (2), a CO2 cold side outlet return port (3), a CO2 hot side outlet return port (6), a CO2 hot side outlet (7), a cooling water outlet return port (9) and a cooling water outlet (10) at the same position as the heat medium plate (B) and the cooling medium plate (C);

Six external interfaces of the heat exchanger are arranged on one side of a front cover plate (A), a CO2 hot side inlet (1) on the front cover plate (A) is connected with a CO2 hot side inlet pipeline outside the heat exchanger, a CO2 cold side outlet return port (3) is connected with an external CO2 cold side outlet pipeline, a cooling water inlet (4) is connected with an external cooling water inlet pipeline, a CO2 hot side outlet return port (6) is connected with an external CO2 hot side outlet pipeline, a CO2 cold side inlet (8) is connected with an external CO2 cold side inlet pipeline, and a cooling water outlet return port (9) is connected with an external cooling water outlet pipeline;

Three baffling seal heads (E) are welded on the rear cover plate (D), the three baffling seal heads (E) are respectively communicated with the CO2 hot side outlet (7) and the CO2 hot side outlet return port (6), the cooling water outlet (10) and the cooling water outlet return port (9) and the CO2 cold side outlet (2) and the CO2 cold side outlet return port (3);

And the front cover plate (A), the plurality of heat medium plates (B), the plurality of cold medium plates (C) and the rear cover plate (D) are all provided with heat insulation lightening holes (5) at the same position along the axial direction.

2. A heat exchange method of a series-connected PCHE heat exchanger adapted to a cylindrical arrangement according to claim 1, characterized in that high temperature CO2 flows into the heat exchanger from the CO2 hot side inlet (1) of the front cover plate (a), is dispersed in each heat medium plate (B), flows along the micro-channels in the heat medium plates (B), and then flows out from the CO2 hot side outlet (7) of the heat medium plates (B) in a converging manner, flows to the baffle head (E) of the rear cover plate (D), and is folded in the baffle head (E) to the external pipe of the CO2 hot side outlet communicating from the CO2 hot side outlet return port (6) flowing from back to front cover plate (a);

The low-temperature CO2 flows into the heat exchanger from a CO2 cold side inlet (8) of the front cover plate (A), is dispersed in CO2 channels of each cold medium plate (C), flows along micro channels in the cold medium plates (C), then flows out from a CO2 cold side outlet (2) of the cold medium plates (C) in a converging way, flows to a baffling seal head (E) of the rear cover plate (D), and is folded into a CO2 cold side outlet external pipeline communicated with the front cover plate (A) from a CO2 cold side outlet return port (3) from back to front in the baffling seal head (E);

Cooling water flows into the heat exchanger from the cooling water inlet (4) of the front cover plate (A), is dispersed in the micro-channels of each cooling medium sheet (C), flows along the micro-channels in the cooling medium sheet (C), flows out from the micro-cooling water side outlet (10) of the cooling medium sheet in a converging way, flows to the baffling seal head (E) of the rear cover plate (D), and is folded into a cooling water outlet external pipeline communicated with the front cover plate (A) from the cooling water outlet return port (9) from back to front in the baffling seal head (E); realizing heat exchange.