High-temperature and high-pressure external heat exchange oil field steam injection device

Abstract

The utility model relates to the technical field of oil and gas field thickened oil recovery, in particular to a high-temperature and high-pressure external heat exchange oil field steam injection device which comprises a boiler radiation section, an external sleeve heat exchange device, a steam-water separator and a superheater. A second steam pipeline is communicated between the external sleeve heat exchange device and the steam-water separator, a third steam pipeline is communicated between the steam-water separator and the superheater, a fourth steam pipeline is communicated between the superheater and the external sleeve heat exchange device, and the external sleeve heat exchange device is communicated with a steam injection pipeline. The device is reasonable and compact in structure and convenient to use, salt deposition and scaling of gas injection system equipment can be avoided, energy can be saved, and the heat efficiency of the boiler can be improved.

Description

Technical Field

[0001] The utility model relates to the technical field of heavy oil exploitation in oil and gas fields, and is a high-temperature and high-pressure external heat exchange oil field steam injection device. Background Art

[0002] Oilfield steam injection boilers are widely used in the field of heavy oil extraction, which requires energy saving and improved thermal efficiency. High-temperature purified water is used as feed water for oilfield steam injection boilers. It has high mineralization (≤7000mg / L) and high temperature (50℃ to 150℃).

[0003] Since the steam generated by the steam injection boiler in the oil field has a high salt content and poor steam quality, during the thermal recovery of ultra-heavy oil, the salts in the boiler feed water enter the steam injection system along with the superheated steam. This has two disadvantages. On the one hand, it causes scaling of equipment such as the boiler body, steam injection pipeline network, wellhead valves, and oil pipes, affecting the safe operation of the steam injection system and increasing operating costs. On the other hand, the salts in the water enter the formation and pollute the formation. Summary of the invention

[0004] The utility model provides a high-temperature and high-pressure oilfield steam injection device with external heat exchange, which overcomes the deficiencies of the above-mentioned prior art and can effectively solve the problems of high heat loss, serious salt and scaling of equipment, and high salt content in oilfield steam injection and discharge of high-salt saturated water in the existing oilfield steam injection system.

[0005] The technical solution of the utility model is achieved through the following measures: a high-temperature and high-pressure oilfield steam injection device with external heat exchange, comprising a boiler radiation section, an external casing heat exchange device, a steam-water separator, and a superheater, a first steam pipeline is fixedly connected between the boiler radiation section outlet and the first inlet at the bottom of the external casing heat exchange device, a second steam pipeline is fixedly connected between the first outlet at the top of the external casing heat exchange device and the inlet at the bottom of the steam-water separator, a third steam pipeline is fixedly connected between the top outlet of the steam-water separator and the upper inlet of the superheater, a fourth steam pipeline is fixedly connected between the lower outlet of the superheater and the second inlet at the bottom of the external casing heat exchange device, and a steam injection pipeline is fixedly connected to the second outlet at the top of the external casing heat exchange device.

[0006] The following are further optimizations and / or improvements to the above utility model technical solution:

[0007] The above-mentioned external sleeve heat exchange device includes a plurality of groups of heat exchange tube groups, connecting pipes and fixed brackets arranged at intervals in front and behind. Each heat exchange tube group is fixedly installed on the fixed bracket. The connecting pipes include an outer tube inlet connecting pipe, an outer tube outlet connecting pipe, an inner tube inlet connecting pipe and an inner tube outlet connecting pipe. The first inlets at the bottom of any two adjacent groups of heat exchange tube groups are fixedly connected with an outer tube inlet connecting pipe, the first outlets at the top of any two adjacent groups of heat exchange tube groups are fixedly connected with an outer tube outlet connecting pipe, the second inlets at the bottom of any two adjacent groups of heat exchange tube groups are fixedly connected with an inner tube inlet connecting pipe, and the second outlets at the top of any two adjacent groups of heat exchange tube groups are fixedly connected with an inner tube outlet connecting pipe.

[0008] The above-mentioned heat exchange tube group is a serpentine sleeve, which includes a serpentine inner tube and a serpentine outer tube. The outer part of the serpentine inner tube is sheathed with a serpentine outer tube. The serpentine inner tube is composed of at least two straight inner tubes spaced apart from each other up and down and connected end to end by at least one U-shaped bend inner tube. The serpentine outer tube is composed of at least two straight outer tubes spaced apart from each other up and down and connected end to end by at least one U-shaped bend outer tube. The outer part of the U-shaped bend inner tube is sheathed with a U-shaped bend outer tube. The outer part of the straight inner tube is sheathed with a straight outer tube. A plurality of straight fins are evenly arranged along the circumference between the outside of the straight inner tube and the inside of the straight outer tube.

[0009] An outer tube inlet connecting pipe is fixedly connected between the left end inlets of the straight outer tubes at the bottom of any two adjacent groups of serpentine casings, an outer tube outlet connecting pipe is fixedly connected between the left end outlets of the straight outer tubes at the top of any two adjacent groups of serpentine casings, an inner tube inlet connecting pipe is fixedly connected between the left end inlets of the straight inner tubes at the bottom of any two adjacent groups of serpentine casings, and an inner tube outlet connecting pipe is fixedly connected between the left end outlets of the straight inner tubes at the top of any two adjacent groups of serpentine casings.

[0010] The above-mentioned fixed bracket includes a base, a support group, and a support rod. Two or more support groups are arranged on the left and right sides of the base. Each support group includes a number of supports arranged at intervals in front and behind. Any two adjacent groups of serpentine sleeves are fixed on the supports through the support rod.

[0011] A first steam pipeline is fixedly connected between the outlet of the boiler radiation section and the outer tube inlet connecting pipe, a second steam pipeline is fixedly connected between the outer tube outlet connecting pipe and the bottom inlet of the steam-water separator, a fourth steam pipeline is fixedly connected between the lower outlet of the superheater and the inner tube inlet connecting pipe, and a steam injection pipeline is fixedly connected to the inner tube outlet connecting pipe.

[0012] The left end sewage outlet of the straight outer tube and the left end sewage outlet of the straight inner tube at the bottom of each group of serpentine sleeves are fixedly connected to the first discharge pipe and the second discharge pipe respectively, and the left end sewage outlet of the straight inner tube at the top of each group of serpentine sleeves is fixedly connected to the third discharge pipe.

[0013] The bottom outlet of the steam-water separator is fixedly connected with a fourth discharge pipe.

[0014] Valves are fixedly installed on the first discharge pipe, the second discharge pipe, the third discharge pipe and the fourth discharge pipe.

[0015] The first steam pipeline and the steam injection pipeline are both fixedly installed with valves, pressure gauges and thermometers in sequence along the medium flow direction, and the third steam pipeline and the fourth steam pipeline are both fixedly installed with valves and thermometers in sequence along the medium flow direction.

[0016] The utility model has a reasonable and compact structure and is easy to use. It can improve the thermal efficiency of the boiler in the oil field steam injection system, avoid salt and scaling problems of various equipment, and reduce the salt content in the oil field steam injection and discharge of high-salt saturated water. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Attached Figure 1 This is a schematic diagram of the process flow of the utility model.

[0018] Attached Figure 2 It is a schematic diagram of the cross-sectional structure of the straight inner tube, the straight outer tube and the straight fins in the utility model.

[0019] The codes in the attached drawings are: 1 is the boiler radiation section, 2 is the steam-water separator, 3 is the superheater, 4 is the first steam pipeline, 5 is the second steam pipeline, 6 is the third steam pipeline, 7 is the fourth steam pipeline, 8 is the steam injection pipeline, 9 is the sewage outlet, 13 is the serpentine sleeve, 14 is the serpentine inner tube, 15 is the serpentine outer tube, 16 is the straight inner tube, 17 is the U-shaped bend inner tube, 18 is the straight outer tube, 19 is the U-shaped bend outer tube, 20 is the straight fin, 21 is the base, 22 is the support, 23 is the support rod, 24 is the first discharge pipe, 25 is the second discharge pipe, 26 is the third discharge pipe, 27 is the fourth discharge pipe, 28 is the valve, 29 is the pressure gauge, and 30 is the thermometer. DETAILED DESCRIPTION

[0020] The present invention is not limited by the following embodiments, and specific implementation methods can be determined according to the technical solution of the present invention and actual conditions.

[0021] In the present invention, unless otherwise specified, the equipment and devices used are all the equipment and devices known and used in the art.

[0022] In the present invention, for the convenience of description, the relative position relationship of each component is described according to the attached manual. Figure 1 and 2 The layout is described in detail, such as the positional relationship of front, back, top, bottom, left, right, etc., which is based on the attached manual. Figure 1 and 2 It is determined by the layout direction.

[0023] The present invention is further described below in conjunction with the embodiments and drawings:

[0024] Embodiment 1: As attached Figure 1 As shown, the high-temperature and high-pressure external heat exchange oil field steam injection device comprises a boiler radiation section 1, an external casing heat exchange device, a steam-water separator 2, and a superheater 3. A first steam pipeline 4 is fixedly connected between the outlet of the boiler radiation section 1 and the first inlet at the bottom of the external casing heat exchange device, a second steam pipeline 5 is fixedly connected between the first outlet at the top of the external casing heat exchange device and the bottom inlet of the steam-water separator 2, a third steam pipeline 6 is fixedly connected between the top outlet of the steam-water separator 2 and the upper inlet of the superheater 3, a fourth steam pipeline 7 is fixedly connected between the lower outlet of the superheater 3 and the second inlet at the bottom of the external casing heat exchange device, and a steam injection pipeline 8 is fixedly connected to the second outlet at the top of the external casing heat exchange device.

[0025] According to actual needs, the above-mentioned high temperature and high pressure external heat exchange oil field steam injection device can be further optimized and / or improved:

[0026] Embodiment 2: It is different from Embodiment 1 in that: Figure 1 As shown, the external sleeve heat exchange device includes a plurality of groups of heat exchange tube groups, connecting pipes and fixed brackets arranged at intervals in front and behind, each group of heat exchange tube groups is fixedly installed on the fixed bracket, and the connecting pipes include an outer tube inlet connecting pipe, an outer tube outlet connecting pipe, an inner tube inlet connecting pipe and an inner tube outlet connecting pipe. The first inlets at the bottom of any two adjacent groups of heat exchange tube groups are fixedly connected with an outer tube inlet connecting pipe, the first outlets at the top of any two adjacent groups of heat exchange tube groups are fixedly connected with an outer tube outlet connecting pipe, the second inlets at the bottom of any two adjacent groups of heat exchange tube groups are fixedly connected with an inner tube inlet connecting pipe, and the second outlets at the top of any two adjacent groups of heat exchange tube groups are fixedly connected with an inner tube outlet connecting pipe.

[0027] Embodiment 3: It differs from Embodiment 1 to Embodiment 2 in that: Figure 1 , 2 As shown, the heat exchange tube group is a serpentine sleeve 13, which includes a serpentine inner tube 14 and a serpentine outer tube 15. The outer part of the serpentine inner tube 14 is sheathed with the serpentine outer tube 15. The serpentine inner tube 14 is composed of at least two straight inner tubes 16 spaced apart from each other and connected end to end by at least one U-shaped bend inner tube 17. The serpentine outer tube 15 is composed of at least two straight outer tubes 18 spaced apart from each other and connected end to end by at least one U-shaped bend outer tube 19. The outer part of the U-shaped bend inner tube 17 is sheathed with a U-shaped bend outer tube 19. The outer part of the straight inner tube 16 is sheathed with the straight outer tube 18. A plurality of straight fins 20 are evenly arranged along the circumference between the outer part of the straight inner tube 16 and the inner part of the straight outer tube 18.

[0028] As required, the straight fins 20 can divide the steam in the serpentine outer tube 15 into several channels to prevent the circulating steam in the serpentine outer tube 15 from flowing biasedly, which is beneficial to uniform heat transfer of the medium between the serpentine outer tube 15 and the serpentine inner tube 14.

[0029] Embodiment 4: It differs from Embodiments 1 to 3 in that: Figure 1 As shown, an outer tube inlet connecting pipe is fixedly connected between the left end inlets of the straight outer tubes 18 at the bottom of any two adjacent groups of serpentine sleeves 13, an outer tube outlet connecting pipe is fixedly connected between the left end outlets of the straight outer tubes 18 at the top of any two adjacent groups of serpentine sleeves 13, an inner tube inlet connecting pipe is fixedly connected between the left end inlets of the straight inner tubes 16 at the bottom of any two adjacent groups of serpentine sleeves 13, and an inner tube outlet connecting pipe is fixedly connected between the left end outlets of the straight inner tubes 16 at the top of any two adjacent groups of serpentine sleeves 13.

[0030] Embodiment 5: It differs from Embodiments 1 to 4 in that: Figure 1 As shown, the fixed bracket includes a base 21, a support group, and a support rod 23. Two or more support groups are arranged at intervals on the left and right sides of the base 21. Each support group includes a plurality of supports 22 arranged at intervals in the front and back. Any two adjacent groups of serpentine sleeves 13 are fixed on the supports 22 through the support rods 23.

[0031] Embodiment 6: It differs from Embodiments 1 to 5 in that: Figure 1 As shown, a first steam pipeline 4 is fixedly connected between the outlet of the boiler radiation section 1 and the outer tube inlet connecting pipe, a second steam pipeline 5 is fixedly connected between the outer tube outlet connecting pipe and the bottom inlet of the steam-water separator 2, a fourth steam pipeline 7 is fixedly connected between the lower outlet of the superheater 3 and the inner tube inlet connecting pipe, and a steam injection pipeline 8 is fixedly connected to the inner tube outlet connecting pipe.

[0032] Embodiment 7: It differs from Embodiments 1 to 6 in that: Figure 1 As shown, the left end sewage outlet 9 of the straight outer tube 18 at the bottom of each group of serpentine sleeves 13 and the left end sewage outlet 9 of the straight inner tube 16 are fixedly connected to the first discharge pipe 24 and the second discharge pipe 25 respectively, and the left end sewage outlet 9 of the straight inner tube 16 at the top of each group of serpentine sleeves 13 is fixedly connected to the third discharge pipe 26.

[0033] Embodiment 8: It differs from Embodiments 1 to 7 in that: Figure 1 As shown, the bottom outlet of the steam-water separator 2 is fixedly connected to a fourth discharge pipe 27 .

[0034] Embodiment 9: It differs from Embodiments 1 to 8 in that: Figure 1 As shown, valves 28 are fixedly installed on the first discharge pipe 24 , the second discharge pipe 25 , the third discharge pipe 26 , and the fourth discharge pipe 27 .

[0035] Embodiment 10: It differs from Embodiments 1 to 9 in that: Figure 1As shown, valves 28, pressure gauges 29, and thermometers 30 are fixedly installed in sequence on the first steam pipeline 4 and the steam injection pipeline 8 along the flow direction of the medium, and valves 28 and thermometers 30 are fixedly installed in sequence on the third steam pipeline 6 and the fourth steam pipeline 7 along the flow direction of the medium.

[0036] As required, the pipelines and equipment of the high-temperature and high-pressure external heat exchange oil field steam injection device can also be equipped with conventional valves, thermometers and pressure gauges known in the art according to production needs.

[0037] The implementation effects of the utility model are as follows:

[0038] (1) The device has high heat exchange efficiency and effectively improves the dryness of the wet saturated steam discharged from the boiler radiation section (the dryness is increased to more than 95%).

[0039] (2) The device reduces the salt content in the steam injected into the oil well, reduces the salt content of the small amount of saturated water discharged from the gas-liquid separator and the serpentine casing device, and reduces the discharge of concentrated brine to 5% or less;

[0040] (3) The device reduces the heat loss of the boiler to 2.8% or less, reducing the heat loss and thus improving the thermal efficiency of the boiler;

[0041] (4) The device has good desalination effect and can avoid salt and scaling in the steam injection system equipment;

[0042] (5) The serpentine shell and tube heat exchanger in the device is a skid-mounted structure, which is easy to transport and install, and has safe and reliable operation.

[0043] The above technical features respectively constitute various embodiments of the present invention, which have strong adaptability and implementation effect. Non-essential technical features can be added or reduced according to actual needs to meet the requirements of different situations.

[0044] The use process of the utility model is as follows: first, the wet saturated steam in the boiler radiation section 1 enters the serpentine outer tube 15 through the first steam pipeline 4 to be circulated upward; at the same time, the wet saturated steam circulated to the straight outer tube 18 at the top of the serpentine outer tube 15 enters the steam-water separator 2 through the second steam pipeline 5 to separate steam and water, and obtain dry steam; then, the dry steam enters the superheater 3 through the third steam pipeline 6 to be heated to obtain high-temperature dry steam; then, the high-temperature dry steam enters the serpentine inner tube 14 through the fourth steam pipeline 7 to be circulated upward, the circulating steam in the serpentine outer tube 15 heats and heats the circulating steam in the serpentine inner tube 14, and the steam in the serpentine inner tube 14 expands due to the heat to obtain high-temperature and high-pressure dry steam, and finally, the high-temperature and high-pressure dry steam in the serpentine inner tube 14 enters the oil well steam injection network through the steam injection pipeline 8.

Claims

1. A high temperature and high pressure external heat exchange oil field steam injection device, characterized in that The invention comprises a boiler radiation section, an external casing heat exchange device, a steam-water separator, and a superheater. A first steam pipeline is fixedly connected between the outlet of the boiler radiation section and the first inlet at the bottom of the external casing heat exchange device. A second steam pipeline is fixedly connected between the first outlet at the top of the external casing heat exchange device and the inlet at the bottom of the steam-water separator. A third steam pipeline is fixedly connected between the outlet at the top of the steam-water separator and the upper inlet of the superheater. A fourth steam pipeline is fixedly connected between the lower outlet of the superheater and the second inlet at the bottom of the external casing heat exchange device. A steam injection pipeline is fixedly connected to the second outlet at the top of the external casing heat exchange device. The external casing heat exchange device comprises a front A plurality of heat exchange tube groups, connecting pipes and fixed brackets are arranged at intervals at the rear, each heat exchange tube group is fixedly installed on the fixed bracket, the connecting pipes include an outer tube inlet connecting pipe, an outer tube outlet connecting pipe, an inner tube inlet connecting pipe and an inner tube outlet connecting pipe, the first inlets at the bottom of any two adjacent heat exchange tube groups are fixedly connected with an outer tube inlet connecting pipe, the first outlets at the top of any two adjacent heat exchange tube groups are fixedly connected with an outer tube outlet connecting pipe, the second inlets at the bottom of any two adjacent heat exchange tube groups are fixedly connected with an inner tube inlet connecting pipe, and the second outlets at the top of any two adjacent heat exchange tube groups are fixedly connected with an inner tube outlet connecting pipe.

2. The high temperature and high pressure external heat exchange oil field steam injection device according to claim 1, characterized in that The heat exchange tube group is a serpentine sleeve, which includes a serpentine inner tube and a serpentine outer tube. The outer part of the serpentine inner tube is sheathed with a serpentine outer tube. The serpentine inner tube is composed of at least two straight inner tubes spaced apart from each other and connected end to end by at least one U-shaped bend inner tube. The serpentine outer tube is composed of at least two straight outer tubes spaced apart from each other and connected end to end by at least one U-shaped bend outer tube. The outer part of the U-shaped bend inner tube is sheathed with a U-shaped bend outer tube. The outer part of the straight inner tube is sheathed with a straight outer tube. A plurality of straight fins are evenly arranged along the circumference between the outside of the straight inner tube and the inside of the straight outer tube.

3. The high temperature and high pressure external heat exchange oil field steam injection device according to claim 2, characterized in that An outer tube inlet connecting pipe is fixedly connected between the left end inlets of the straight outer tubes at the bottom of any two adjacent groups of serpentine casings, an outer tube outlet connecting pipe is fixedly connected between the left end outlets of the straight outer tubes at the top of any two adjacent groups of serpentine casings, an inner tube inlet connecting pipe is fixedly connected between the left end inlets of the straight inner tubes at the bottom of any two adjacent groups of serpentine casings, and an inner tube outlet connecting pipe is fixedly connected between the left end outlets of the straight inner tubes at the top of any two adjacent groups of serpentine casings.

4. The high temperature and high pressure external heat exchange oil field steam injection device according to claim 1, 2 or 3, characterized in that The fixed bracket includes a base, a support group, and a support rod. Two or more support groups are arranged on the base at intervals on the left and right. Each support group includes a number of supports arranged at intervals in front and behind. Any two adjacent groups of serpentine sleeves are fixed on the supports through the support rod.

5. The high temperature and high pressure external heat exchange oil field steam injection device according to claim 4, characterized in that A first steam pipeline is fixedly connected between the outlet of the boiler radiation section and the outer tube inlet connecting pipe, a second steam pipeline is fixedly connected between the outer tube outlet connecting pipe and the bottom inlet of the steam-water separator, a fourth steam pipeline is fixedly connected between the lower outlet of the superheater and the inner tube inlet connecting pipe, and a steam injection pipeline is fixedly connected to the inner tube outlet connecting pipe.

6. The high temperature and high pressure external heat exchange oil field steam injection device according to claim 2, 3 or 5, characterized in that The left end sewage outlet of the straight outer tube at the bottom of each group of serpentine sleeves and the left end sewage outlet of the straight inner tube are fixedly connected to the first discharge pipe and the second discharge pipe respectively, and the left end sewage outlet of the straight inner tube at the top of each group of serpentine sleeves is fixedly connected to the third discharge pipe.

7. The high temperature and high pressure external heat exchange oil field steam injection device according to claim 6, characterized in that The bottom outlet of the steam-water separator is fixedly connected with a fourth discharge pipe.

8. The high temperature and high pressure external heat exchange oil field steam injection device according to claim 7, characterized in that Valves are fixedly installed on the first discharge pipe, the second discharge pipe, the third discharge pipe and the fourth discharge pipe.

9. The high temperature and high pressure external heat exchange oil field steam injection device according to claim 8, characterized in that Valves, pressure gauges and thermometers are fixedly installed in sequence on the first steam pipeline and the steam injection pipeline along the medium flow direction. Valves and thermometers are fixedly installed in sequence on the third steam pipeline and the fourth steam pipeline along the medium flow direction.

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