Device for Removing and Preventing Paraffin by Using Electric Heating Generated from Skin Effect-based Natural Gas Electricity and Application thereof

Abstract

A device for removing and preventing paraffin by using electric heating generated from skin effect-based natural gas electricity and an application thereof are disclosed, and the device comprises a natural gas collection portion, a natural gas electricity generation portion and a device for removing and preventing paraffin by using electric heating powered by the natural gas electricity generation portion; the natural gas collection portion is used to collect and separate natural gases discharged from a wellbore; the natural gas electricity generation portion generates electricity with natural gases. The power source required by the electric heating of the steel armored cable of the present invention comes from the natural gas electricity generation portion, and the air source required by the natural gas electricity generation portion can be obtained directly from the associated gases extracted from an oil well.

Claims

1. A device for removing and preventing paraffin by using electric heating generated from skin effect-based natural gas electricity, characterized in that the device comprises a natural gas collection portion, a natural gas electricity generation portion and a device for removing and preventing paraffin by using electric heating powered by the natural gas electricity generation portion; the natural gas collection portion is used to collect and separate natural gas discharged from a wellbore; and the natural gas electricity generation portion generates electricity with the natural gas.

2. The device for removing and preventing paraffin by using electric heating generated from skin effect-based natural gas electricity according to claim 1, characterized in that the natural gas collection portion comprises an oil-gas metering station, a joint processing station and a natural gas purifying station that are successively connected to the wellbore.

3. The device for removing and preventing paraffin by using electric heating generated from skin effect-based natural gas electricity according to claim 2, characterized in that an oil storage tank is arranged to be connected with the joint processing station.

4. The device for removing and preventing paraffin by using electric heating generated from skin effect-based natural gas electricity according to claim 2, characterized in that a gas storage tank is arranged to be connected with the natural gas purifying station.

5. The device for removing and preventing paraffin by using electric heating generated from skin effect-based natural gas electricity according to claim 1, characterized in that the natural gas electricity generation portion comprises a natural gas generator set and a power frequency electric heating control cabinet that are connected; and the power frequency electric heating control cabinet is used to control the device for removing and preventing paraffin by using electric heating.

6. The device for removing and preventing paraffin by using electric heating generated from skin effect-based natural gas electricity according to claim 5, characterized in that the device for removing and preventing paraffin by using electric heating comprises a steel armored cable extending into the wellbore sealedly through a Christmas tree, and the steel armored cable is connected with the power frequency electric heating control cabinet.

7. The device for removing and preventing paraffin by using electric heating generated from skin effect-based natural gas electricity according to claim 6, characterized in that the steel armored cable comprises a steel armored sheath, an insulating material layer, a polytetrafluoroethylene layer and a cable core wire that are successively arranged from outside to inside.

8. The device for removing and preventing paraffin by using electric heating generated from skin effect-based natural gas electricity according to claim 7, characterized in that the steel armored sheath is a contiguously seamless steel tube.

9. The device for removing and preventing paraffin by using electric heating generated from skin effect-based natural gas electricity according to claim 6, characterized in that the device for removing and preventing paraffin by using electric heating further comprises a wellhead high-pressure sealing system arranged on the top of the Christmas tree; and the wellhead high-pressure sealing system comprises a pressing cap, a sealing packing, a spring, a wedge disc and a cable clamping plate that are passed through successively by the steel armored cable.

10. The device for removing and preventing paraffin by using electric heating generated from skin effect-based natural gas electricity according to claim 9, characterized in that a suspension connector is further arranged on the top of the pressing cap.

11. The device for removing and preventing paraffin by using electric heating generated from skin effect-based natural gas electricity according to claim 6, characterized in that the device for removing and preventing paraffin by using electric heating further comprises a centralized heater that is arranged on a tail end of the steel armored cable stretching into the well, the centralized heater comprises a resistance wire connected with the steel armored cable, and a thermal conductive insulating layer is arranged outside of the resistance wire.

12. The device for removing and preventing paraffin by using electric heating generated from skin effect-based natural gas electricity according to claim 11, characterized in that the steel armored cable is connected respectively with the resistance wire and the thermal conductive insulating layer through a double-ferrule fitting.

13. The device for removing and preventing paraffin by using electric heating generated from skin effect-based natural gas electricity according to claim 11, characterized in that the thermal conductive insulating layer is a thermal conductive silica gel layer.

14. The device for removing and preventing paraffin by using electric heating generated from skin effect-based natural gas electricity according to claim 1, characterized in that the natural gas electricity generation portion comprises a natural gas generator set and multiple sets of power frequency electric heating control cabinets; the multiple sets of power frequency electric heating control cabinets are used for correspondingly controlling the devices for removing and preventing paraffin by using electric heating mounted in a plurality of wellbores respectively.

15. A working method of the device for removing and preventing paraffin by using electric heating generated from skin effect-based natural gas electricity according to claim 7, characterized in that the working method comprises the following steps: 1) the natural gas collection portion collects and separates out the natural gas in the wellbore and transmits the natural gas to the natural gas electricity generation portion for electricity generation; 2) the natural gas electricity generation portion supplies variable-frequency power for the device for removing and preventing paraffin by using electric heating: the power frequency electric heating control cabinet outputs variable-frequency power, a live line of the power frequency electric heating control cabinet is connected with the cable core wire of the steel armored cable; and a zero line of the power frequency electric heating control cabinet is connected with the steel armored sheath of the steel armored cable; so that the cable core wire and the steel armored sheath form a loop, and thermal energy can be generated on an outer wall of the steel armored sheath via the skin effect, so as to remove paraffin or prevent paraffin from forming in the wellbore by crude oil.

16. The working method of the device for removing and preventing paraffin by using electric heating generated from skin effect-based natural gas electricity according to claim 15, characterized in that the method further comprises steps of lowering the steel armored cable into the wellbore and lifting the steel armored cable out of the wellbore: 3) when the steel armored cable is lowered into the wellbore, the spring opens the wedge disc, the steel armored cable enters the wellbore, and then the steel armored cable, the pressing cap, the sealing packing, the spring and the wedge disc form a high-pressure wellhead seal, to achieve a high pressure sealing effect in the lowering process and a heating process of the steel armored cable; 4) when the steel armored cable is lifted out of the wellbore, the spring resets to close the wedge disc to prevent oil-gas fluid from spewing out along the wellhead.

17. The working method of the device for removing and preventing paraffin by using electric heating generated from skin effect-based natural gas electricity according to claim 15, characterized in that the method further comprises a step for a condition when the steel armored cable accidentally drops into the wellbore: 5) when the steel armored cable accidentally drops into the wellbore, the spring resets to close the wedge disc to prevent oil-gas fluid from spewing out along the wellhead.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0047] FIG. 1 is a structural schematic view of a device for removing and preventing paraffin by using electric heating generated from skin effect-based natural gas electricity described in the present invention;

[0048] FIG. 2 is a schematic sectional view of a steel armored cable described in the present invention;

[0049] FIG. 3 is a structural schematic view of a centralized heater described in the present invention;

[0050] FIG. 4 is a structural schematic view of a natural gas power generation device for removing and preventing paraffin by using electric heating based on a skin effect of an embodiment 10 of the invention;

[0051] In FIGS. 1 to 4, 1, power transmission line; 2, suspension connector; 3, pressing cap; 4, sealing packing; 5, spring; 6, wedge disc; 7, cable clamping plate; 8, flange; 9, Christmas tree; 10, well cementation cement wall; 11, casing pipe; 12, wellbore; 13, steel armored cable; 14, oil-gas mixing transportation pipeline; 15, oil-gas metering station; 16, oil-gas mixing transportation pipeline; 17, joint processing station; 18, oil transportation pipeline; 19, oil storage tank; 20, natural gas transportation pipeline; 21, natural gas purifying station; 22, natural gas transportation pipeline; 23, gas storage tank; 24, natural gas transportation pipeline; 25, natural gas generator set; 26, power transmission line; 27, power frequency electric heating control cabinet; 28, steel armored sheath; 29, insulating material layer; 30, polytetrafluoroethylene layer; 31, cable core wire; 32, centralized heater; 33, double-ferrule fitting; 34, thermal conductive insulating layer; 35, resistance wire.

[0052] In FIG. 4, 27-1, first power frequency electric heating control cabinet; 27-2, second power frequency electric heating control cabinet; 27-3, third power frequency electric heating control cabinet; 27-4, fourth power frequency electric heating control cabinet;

[0053] 9-1, first Christmas tree; 9-2, second Christmas tree; 9-3, third Christmas tree; 9-4, fourth Christmas tree.

DETAILED DESCRIPTION OF THE INVENTION

[0054] The detailed description of the invention is given herein below by combining with the description and the accompanying drawings, but is not limited to it.

Embodiment 1

[0055] A device for removing and preventing paraffin by using electric heating generated from skin effect-based natural gas electricity comprises a natural gas collection portion, a natural gas electricity generation portion and a device for removing and preventing paraffin by using electric heating powered by the natural gas electricity generation portion;

[0056] the natural gas collection portion is used to collect and separate natural gas discharged from of a wellbore 12;

[0057] the natural gas electricity generation portion utilizes the natural gas to generate electricity.

[0058] The natural gas collection portion comprises an oil-gas metering station 15, a joint processing station 17 and a natural gas purifying station 21 that are successively connected to the wellbore 12.

[0059] The natural gas electricity generation portion comprises a natural gas generator set 25 and a power frequency electric heating control cabinet 27 that are connected; and the power frequency electric heating control cabinet 27 is used to control the device for removing and preventing paraffin by using electric heating.

[0060] The device for removing and preventing paraffin by using electric heating comprises a steel armored cable 13 extending into the wellbore 12 sealedly through a Christmas tree 9, and the steel armored cable 13 is connected with the power frequency electric heating control cabinet 27.

Embodiment 2

[0061] The device for removing and preventing paraffin by using electric heating generated from skin effect-based natural gas electricity described in the embodiment 1, characterized in that the steel armored cable 13 comprises a steel armored sheath 28, an insulating material layer 29, a polytetrafluoroethylene layer 30 and a cable core wire 31 that are successively arranged from outside to inside.

[0062] The steel armored sheath 28 is a contiguously seamless steel tube.

Embodiment 3

[0063] The device for removing and preventing paraffin by using electric heating generated from skin effect-based natural gas electricity described in the embodiment 2, characterized in that the device for removing and preventing paraffin by using electric heating further comprises a wellhead high-pressure sealing system arranged on top of the Christmas tree 9; The wellhead high-pressure sealing system comprises a pressing cap 3, a sealing packing 4, a spring 5, a wedge disc 6 and a cable clamping plate 7 that are passed through successively by the steel armored cable 13.

[0064] A suspension connector 2 is further arranged on the top of the pressing cap 3.

Embodiment 4

[0065] The working method of the device for removing and preventing paraffin by using electric heating generated from skin effect-based natural gas electricity described in the embodiments 1, 2 and 3 comprises the following steps:

[0066] 1) the natural gas collection portion collects and separates out the natural gas in the wellbore and transmits the natural gas to the natural gas electricity generation portion for electricity generation;

[0067] 2) the natural gas electricity generation portion supplies variable-frequency power for the device for removing and preventing paraffin by using electric heating;

[0068] the power frequency electric heating control cabinet 27 outputs variable-frequency power, a live line of the power frequency electric heating control cabinet 27 is connected with the cable core wire 31 of the steel armored cable 13; and

[0069] a zero line of the power frequency electric heating control cabinet 27 is connected with the steel armored sheath 28 of the steel armored cable 13;

[0070] so that the cable core wire 31 and the steel armored sheath 28 form a loop, and thermal energy can be generated on an outer wall of the steel armored sheath 28 via the skin effect, so as to remove paraffin or prevent paraffin from forming in the wellbore 12 by crude oil.

Embodiment 5

[0071] The working method of the device for removing and preventing paraffin by using electric heating generated from skin effect-based natural gas electricity described in embodiment 3 differs from embodiment 4 in that the working method further comprises steps of lowering the steel armored cable into the wellbore and lifting the steel armored cable out of the wellbore:

[0072] 3) when the steel armored cable 13 is lowered into the wellbore 12, the spring 5 opens the wedge disc 6, the steel armored cable 13 enters the wellbore 12, and the steel armored cable 13, the pressing cap 3, the sealing packing 4, the spring 5 and the wedge disc 6 form a high-pressure wellhead seal, to achieve a high pressure sealing effect in the lowering process and a heating process of the steel armored cable;

[0073] 4) when the steel armored cable 13 is lifted out of the wellbore 12, the spring 5 resets to close the wedge disc 6 to prevent oil-gas fluid from spewing out along the wellhead.

Embodiment 6

[0074] The working method of the device for removing and preventing paraffin by using electric heating generated from skin effect-based natural gas electricity described in embodiment 3 differs from embodiment 4 in that the working method further comprises a step for a condition when the steel armored cable accidentally drops into the wellbore:

[0075] 4) when the steel armored cable 13 accidentally drops into the wellbore, the spring 5 resets to close the wedge disc 6 to prevent oil-gas fluid from spewing out along the wellhead.

Embodiment 7

[0076] A device for removing and preventing paraffin by using electric heating generated from skin effect-based natural gas electricity described in embodiment 1 differs in that an oil storage tank 19 is arranged to be connected with the joint processing station 17; and a gas storage tank 19 is arranged to be connected with the natural gas purifying station 21.

Embodiment 8

[0077] When there is severe paraffin precipitation in the wellbore 12 of an oil well and the paraffin cannot be completely removed only by heating of the steel armored cable 13, the device for removing and preventing paraffin by using electric heating generated from skin effect-based natural gas electricity differs from embodiments 1, 2 and 3 in that:

[0078] the device for removing and preventing paraffin by using electric heating further comprises a centralized heater 32 that is arranged on a tail end of the steel armored cable 13 stretching into the well, the centralized heater 32 comprises a resistance wire 35 connected with the steel armored cable 13, and a thermal conductive insulating layer 34 is arranged outside of the resistance wire 35. The thermal conductive insulating layer 34 is a thermal conductive silica gel layer.

[0079] The resistance wire 35 and the thermal conductive insulating layer 34 in the centralized heater 32 are used for centralized heating for those locations where paraffin precipitation is severe, thus realizing paraffin melting at the paraffin blockage locations.

Embodiment 9

[0080] A device for removing and preventing paraffin by using electric heating generated from skin effect-based natural gas electricity described in embodiment 8 differs in that the steel armored cable 13 is connected respectively with the resistance wire 35 and the thermal conductive insulating layer 34 through a double-ferrule fitting 33.

Embodiment 10

[0081] This embodiment is shown in FIG. 4.

[0082] For a plurality of relatively concentrated paraffin deposit oil wellbores, a plurality of oil wells need paraffin removal operation simultaneously or alternately, and an electricity generating capacity of the natural gas generator set 25 can be determined according to the quantity of the oil wells.

[0083] The natural gas electricity generation portion comprises a natural gas generator set 25 and four sets of power frequency electric heating control cabinets that are connected: a first power frequency electric heating control cabinet 27-1, a second power frequency electric heating control cabinet 27-2, a third power frequency electric heating control cabinet 27-3, a fourth power frequency electric heating control cabinet 27-4; the four sets of power frequency electric heating control cabinets are used to correspondingly control the devices for removing and preventing paraffin by using electric heating mounted in four wellbores respectively.