Dual-system cascade explosion-proof heat pump

Abstract

The utility model relates to a dual-system cascade explosion-proof heat pump which comprises a frame, and a plurality of heating units are arranged in the frame. The heating unit comprises a plate heat exchanger fixedly installed on the inner bottom wall of the frame, a gas-liquid separator is fixedly installed on the inner bottom wall of the frame, and liquid storage tanks are fixedly installed on the inner bottom wall of the frame and located on the two sides of the plate heat exchanger. The system has the advantages that the high-temperature measuring unit is provided with two heat sources, when the environment temperature is high, the low-temperature side unit is stopped, the high-temperature side evaporator channel is switched, and the two high-temperature side units are used for directly supplying heat, and when the environment temperature is low, the high-temperature measuring plate heat exchanger channel is switched, the low-temperature side unit is used for absorbing heat in air and transferring the heat to the plate heat exchanger; and then the heat in the plate heat exchanger is absorbed by the high-temperature side unit, high heat is prepared and transmitted to the built-in condenser, and the system can keep high operation efficiency under different working conditions through the flexible adjusting mechanism.

Description

Technical Field

[0001] The utility model relates to the technical field of heat pumps, and particularly relates to a dual-system cascade explosion-proof heat pump. Background Technique

[0002] In oil and gas exploitation, due to the high wax content, low freezing point, poor fluidity of the produced oilfield fluid, and easy wall sticking, pipeline condensation and blockage are caused, which is directly reflected as the increase of the wellhead back pressure, affecting the single-well production and the stable production operation of the whole block. Therefore, cascade heat pump units are generally used at the wellhead and metering station to heat the pipeline.

[0003] Since some oilfields are located in the northwest region, and the northwest region is hot in summer and extremely cold in winter. At the same time, the heat pump unit needs to heat the water temperature to more than 70 °C. However, the frequency converter of the low-temperature side variable-frequency compressor of the ordinary cascade heat pump generates a large amount of heat in summer. Therefore, it is necessary to stop the low-temperature side variable-frequency compressor when the room temperature is above 20 °C, and only the high-temperature side fixed-frequency compressor works, which leads to a reduction in system efficiency or unstable heat pump performance, and easily affects the overall heating effect of the system. Content of the Utility Model

[0004] The purpose of the utility model is to provide a dual-system cascade explosion-proof heat pump to solve the above problems existing in the prior art.

[0005] The technical solution of the utility model to solve the above technical problems is as follows:

[0006] A dual-system cascade explosion-proof heat pump includes a frame, and a plurality of heating units are arranged inside the frame;

[0007] The heating unit includes a plate heat exchanger fixedly installed on the inner bottom wall of the frame, a gas-liquid separator fixedly installed on the inner bottom wall of the frame, liquid storage tanks fixedly installed on both sides of the plate heat exchanger on the inner bottom wall of the frame. The plate heat exchanger is connected to the liquid storage tank through a pipeline. A plurality of evaporators are fixedly installed above the plate heat exchanger on the inner top wall of the frame, and a high-temperature side unit and a low-temperature side unit are arranged inside the frame;

[0008] The heating unit also includes a fixing frame fixedly mounted on the inner bottom wall of the frame and located on both sides of the plate heat exchanger; the high-temperature side unit includes a high-temperature compressor fixedly mounted on the inner bottom wall of the frame, the return air port of the high-temperature compressor is connected to the gas-liquid separator through a pipeline, a high-temperature four-way reversing valve is fixedly mounted on the surface of the fixing frame on one side, the exhaust port of the high-temperature compressor is connected to one port of the high-temperature four-way reversing valve through a pipeline, an oil separator is fixedly mounted on the inner bottom wall of the frame, and the other three ports of the high-temperature four-way reversing valve are respectively connected to the oil separator, the evaporator and the plate heat exchanger through pipelines;

[0009] The low-temperature side unit includes a low-temperature compressor fixedly mounted on the inner bottom wall of the frame, the return air port of the low-temperature compressor is connected to the gas-liquid separator through a pipeline, a low-temperature four-way reversing valve is fixedly mounted on the surface of the fixed frame on the other side, four ports of the low-temperature four-way reversing valve are respectively connected to the evaporator, the exhaust port of the low-temperature compressor, the low-temperature four-way reversing valve and the plate heat exchanger through pipelines, an economizer is fixedly mounted on the inner bottom wall of the frame and on one side of the gas-liquid separator, and both ends of the economizer are respectively connected to the evaporator and the liquid storage tank through pipelines.

[0010] The beneficial effects of the utility model are as follows: the evaporator adopts a microchannel structure with two layers, the inner layer is connected to the high temperature side unit, and directly absorbs heat for the high temperature side unit, and the outer layer is connected to the low temperature side unit, and absorbs heat for the low temperature side unit. The plate heat exchanger is used as the low temperature side to supply heat to the high temperature side. The high temperature side unit has two heat sources. When the ambient temperature is high, the low temperature side unit is stopped, and the high temperature side evaporator channel is switched to directly heat the two units on the high temperature side. When the ambient temperature is low, the high temperature plate heat exchanger channel is switched to absorb heat in the air with the low temperature side unit to transfer To the plate heat exchanger, and then the high-temperature side unit absorbs the heat in the plate heat exchanger, and produces high heat to transfer to the built-in condenser. When the heating load demand is large, two groups of heat pump units are used to work at the same time, among which the high-temperature and low-temperature sides are coupled into a group through a plate heat exchanger. When the heating load demand is small, only one of the coupled units of the high-temperature side unit and the low-temperature side unit is started separately. The ambient temperature only cuts off the heating mode of the low-temperature compressor, and uses the high-temperature side to directly absorb heat from the air. This flexible adjustment mechanism enables the system to maintain a high operating efficiency under different working conditions.

[0011] On the basis of the above technical solution, the present invention can also be improved as follows.

[0012] Furthermore, a plurality of fans are fixedly mounted on the upper surface of the frame.

[0013] Furthermore, wind and sand protection covers are provided on the four side surfaces of the frame.

[0014] Further, the wind and sand protection cover includes a protection cover with a triangular side surface and a front surface inclined outward, which is fixedly installed on the surface of the frame, and sand protection nets are fixedly installed at the bottoms of the protection covers.

[0015] Further, sealing plates are detachably installed on the four side surfaces of the frame and below the protection cover.

[0016] Further, a plurality of strip-shaped support legs are fixedly installed at the bottom of the frame. Description of the Drawings

[0017] Figure 1 Schematic diagram of the internal structure of the present utility model Figure 1 ;

[0018] Figure 2 Schematic diagram of the internal structure of the present utility model Figure 2 ;

[0019] Figure 3 Schematic diagram of the internal structure of the present utility model Figure 3 ;

[0020] Figure 4 Schematic diagram of the overall structure of the present utility model;

[0021] Figure 5 Of the present utility model Figure 2 Enlarged view of part A;

[0022] Figure 6 Of the present utility model Figure 2 Enlarged view of part B.

[0023] In the drawings, the list of components represented by each reference numeral is as follows:

[0024] 1. Frame; 2. Heating unit; 21. Plate heat exchanger; 22. Gas-liquid separator; 23. Liquid storage tank; 24. Evaporator; 25. High-temperature side unit; 251. High-temperature compressor; 252. High-temperature four-way reversing valve; 253. Oil separator; 26. Low-temperature side unit; 261. Low-temperature compressor; 262. Low-temperature four-way reversing valve; 263. Economizer; 27. Fixed frame; 3. Fan; 4. Wind and sand protection cover; 41. Protection cover; 42. Sand protection net; 5. Support leg; 6. Sealing plate. Detailed Embodiment

[0025] The principles and features of the present utility model are described below with reference to the drawings. The examples given are only used to explain the present utility model and are not intended to limit the scope of the present utility model.

[0026] As Figures 1 to 6As shown in the figure, Embodiment 1 of the utility model is a dual-system cascade explosion-proof heat pump, which includes a frame 1, and several heating units 2 are arranged inside the frame 1;

[0027] The heating unit 2 includes a plate heat exchanger 21 fixedly installed on the inner bottom wall of the frame 1. A gas-liquid separator 22 is fixedly installed on the inner bottom wall of the frame 1. Liquid storage tanks 23 are fixedly installed on both sides of the plate heat exchanger 21 on the inner bottom wall of the frame 1. The plate heat exchanger 21 is connected to the liquid storage tank 23 through a pipeline. Several evaporators 24 are fixedly installed on the inner top wall of the frame 1 and above the plate heat exchanger 21. A high-temperature side unit 25 and a low-temperature side unit 26 are arranged inside the frame 1;

[0028] The heating unit 2 further includes fixing frames 27 fixedly installed on the inner bottom wall of the frame 1 and on both sides of the plate heat exchanger 21. The high-temperature side unit 25 includes a high-temperature compressor 251 fixedly installed on the inner bottom wall of the frame 1. The suction port of the high-temperature compressor 251 is connected to the gas-liquid separator 22 through a pipeline. A high-temperature four-way reversing valve 252 is fixedly installed on the surface of one side fixing frame 27. The discharge port of the high-temperature compressor 251 is connected to one port of the high-temperature four-way reversing valve 252 through a pipeline. An oil separator 253 is fixedly installed on the inner bottom wall of the frame 1. The other three ports of the high-temperature four-way reversing valve 252 are respectively connected to the oil separator 253, the evaporator 24, and the plate heat exchanger 21 through pipelines;

[0029] The low-temperature side unit 26 includes a low-temperature compressor 261 fixedly installed on the inner bottom wall of the frame 1. The suction port of the low-temperature compressor 261 is connected to the gas-liquid separator 22 through a pipeline. A low-temperature four-way reversing valve 262 is fixedly installed on the surface of the other side fixing frame 27. The four ports of the low-temperature four-way reversing valve 262 are respectively connected to the evaporator 24, the discharge port of the low-temperature compressor 261, the low-temperature four-way reversing valve 262 itself, and the plate heat exchanger 21 through pipelines. An economizer 263 is fixedly installed on the inner bottom wall of the frame 1 and on one side of the gas-liquid separator 22. Both ends of the economizer 263 are respectively connected to the evaporator 24 and the liquid storage tank 23 through pipelines.

[0030] The evaporator 24 adopts a microchannel structure with two layers. The inner layer is connected to the high-temperature side unit 25 to directly absorb heat supply for the high-temperature side unit 25. The outer layer is connected to the low-temperature side unit 26 to absorb heat for the low-temperature side unit 26. The plate heat exchanger 21 supplies heat from the low-temperature side to the high-temperature side. The high-temperature side unit 25 has two heat source supplies. When the ambient temperature is high, the low-temperature side unit 26 is shut down, and the channels of the high-temperature side evaporator 24 are switched to directly supply heat with the two high-temperature side units. When the ambient temperature is low, the channels of the high-temperature side plate heat exchanger 21 are switched. The low-temperature side unit 26 absorbs heat from the air, transfers it to the plate heat exchanger 21, and then the high-temperature side unit 25 absorbs the heat in the plate heat exchanger 21 to produce high-temperature heat and transfer it to the built-in condenser. When the heating load demand is large, two sets of heat pump units work simultaneously. Among them, the high-temperature side and the low-temperature side are coupled as a group through the plate heat exchanger 21. When the heating load demand is small, only one of the high-temperature side unit 25 and the low-temperature side unit 26 is started separately. The ambient temperature only cuts off the heating method of the low-temperature compressor 261, and the high-temperature side directly absorbs heat from the air. This flexible adjustment mechanism enables the system to maintain a high operating efficiency under different working conditions.

[0031] In specific implementation, a pressure sensor is arranged inside the frame 1. Both ends of the pressure sensor are provided with long capillary copper tubes. The other ends of the two long capillary copper tubes are respectively connected to the pipelines near the inlet and outlet of the compressor and the pipelines on the plate heat exchanger 21. By setting the pressure sensor and the long capillary copper tubes, the refrigerant flowing in the pipeline can be cooled, reducing the damage of high temperature to each component. At the same time, when the plate heat exchanger 21 conducts heat exchange coupling, instead of sensing the temperature through the temperature sensor probe, the pressure of the low-temperature side unit is detected by the pressure sensor, and the evaporation temperature is calculated through the pressure, which is more accurate.

[0032] In Embodiment 2 of the present utility model, a double-system cascade explosion-proof heat pump, on the basis of Embodiment 1, several fans 3 are fixedly installed on the upper surface of the frame 1.

[0033] The presence of the fans 3 can accelerate the air flow around the evaporator 24, so that when the air flows through the evaporator 24, the evaporation process can more effectively absorb the heat in the air and reduce the temperature.

[0034] In Embodiment 3 of the present utility model, a double-system cascade explosion-proof heat pump, on the basis of Embodiment 1 or 2, wind and sand shields 4 are arranged on the four side surfaces of the frame 1.

[0035] By setting the wind and sand shields 4, the wind and sand in the air are blocked, preventing the wind and sand in the air from entering the inside of the frame 1.

[0036] Embodiment 4 of the present utility model is a dual-system cascade explosion-proof heat pump. On the basis of Embodiment 3, the wind and sand shield 4 includes a protective cover 41 with a triangular side surface and an inclined front surface fixed and installed on the upper side of the surface of the frame 1. Sand screens 42 are fixedly installed at the bottom of the protective cover 41.

[0037] For the external protective cover 41, the air inlet is directly fixed downward, which can prevent wind and sand, and by using gravity, the sand can fall off, avoiding the accumulation of wind and sand. At the same time, it can better gather the air volume, enable the evaporator 24 to absorb heat evenly, avoid regional frosting affecting the heating capacity. Meanwhile, by setting the sand screens 42, small airborne sand particles are prevented from entering the interior of the frame 1.

[0038] Embodiment 5 of the present utility model is a dual-system cascade explosion-proof heat pump. On the basis of Embodiment 4, sealing plates 6 are detachably installed on the four side surfaces of the frame 1 and below the protective cover 41.

[0039] In specific implementation, the sealing plates 6 are fixedly installed on the frame 1 by bolts.

[0040] By installing the sealing plates 6 in a detachable manner, the staff can perform maintenance on the components inside the frame 1 at any time.

[0041] Embodiment 6 of the present utility model is a dual-system cascade explosion-proof heat pump. On the basis of any one of Embodiments 1 to 5, a plurality of strip-shaped support legs 5 are fixedly installed at the bottom of the frame 1.

[0042] The frame 1 is supported by the support legs 5, so that the bottom of the frame 1 is suspended. The suspended design allows air to freely flow below the frame 1, which helps with heat dissipation and prevents dampness.

[0043] The above are only the preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A dual-system cascade explosion-proof heat pump, characterized in that: It comprises a frame (1), wherein a plurality of heating units (2) are arranged inside the frame (1); The heating unit (2) comprises a plate heat exchanger (21) fixedly mounted on the inner bottom wall of the frame (1); a gas-liquid separator (22) is fixedly mounted on the inner bottom wall of the frame (1); liquid storage tanks (23) are fixedly mounted on the inner bottom wall of the frame (1) and located on both sides of the plate heat exchanger (21); the plate heat exchanger (21) is connected to the liquid storage tank (23) via a pipeline; a plurality of evaporators (24) are fixedly mounted on the inner top wall of the frame (1) and located above the plate heat exchanger (21); and a high-temperature side unit (25) and a low-temperature side unit (26) are arranged inside the frame (1); The heating unit (2) further comprises a fixing frame (27) fixedly mounted on the inner bottom wall of the frame (1) and located on both sides of the plate heat exchanger (21); the high-temperature side unit (25) comprises a high-temperature compressor (251) fixedly mounted on the inner bottom wall of the frame (1); the return air port of the high-temperature compressor (251) is connected to the gas-liquid separator (22) via a pipeline; a high-temperature four-way reversing valve (252) is fixedly mounted on the surface of one side of the fixing frame (27); the exhaust port of the high-temperature compressor (251) is connected to one port of the high-temperature four-way reversing valve (252) via a pipeline; an oil separator (253) is fixedly mounted on the inner bottom wall of the frame (1); the other three ports of the high-temperature four-way reversing valve (252) are respectively connected to the oil separator (253), the evaporator (24) and the plate heat exchanger (21) via pipelines; The low-temperature side unit (26) comprises a low-temperature compressor (261) fixedly mounted on the inner bottom wall of the frame (1); the return air port of the low-temperature compressor (261) is connected to the gas-liquid separator (22) through a pipeline; a low-temperature four-way reversing valve (262) is fixedly mounted on the surface of the fixed frame (27) on the other side; four ports of the low-temperature four-way reversing valve (262) are respectively connected to the evaporator (24), the exhaust port of the low-temperature compressor (261), the low-temperature four-way reversing valve (262) and the plate heat exchanger (21) through pipelines; an economizer (263) is fixedly mounted on the inner bottom wall of the frame (1) and located on one side of the gas-liquid separator (22); two ends of the economizer (263) are respectively connected to the evaporator (24) and the liquid storage tank (23) through pipelines.

2. A dual-system cascade explosion-proof heat pump according to claim 1, characterized in that: A plurality of fans (3) are fixedly mounted on the upper surface of the frame (1).

3. A dual-system cascade explosion-proof heat pump according to claim 1, characterized in that: The four side surfaces of the frame (1) are provided with wind and sand protection covers (4).

4. A dual-system cascade explosion-proof heat pump according to claim 3, characterized in that: The wind and sand protection cover (4) comprises a protection cover (41) which is fixedly mounted on the surface of the frame (1) and has a triangular side surface and a front face inclined outward, and a sand protection net (42) is fixedly mounted on the bottom of the protection cover (41).

5. A dual-system cascade explosion-proof heat pump according to claim 4, characterized in that: Sealing plates (6) are detachably mounted on the four side surfaces of the frame (1) and below the protective cover (41).

6. A dual-system cascade explosion-proof heat pump according to claim 1, characterized in that: A plurality of strip-shaped supporting legs (5) are fixedly mounted on the bottom of the frame (1).

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