CN105756644A - Preheating method before oil extraction of double horizontal wells and oil extraction method of double horizontal wells - Google Patents
Preheating method before oil extraction of double horizontal wells and oil extraction method of double horizontal wells Download PDFInfo
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- CN105756644A CN105756644A CN201410790805.0A CN201410790805A CN105756644A CN 105756644 A CN105756644 A CN 105756644A CN 201410790805 A CN201410790805 A CN 201410790805A CN 105756644 A CN105756644 A CN 105756644A
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- 238000000034 method Methods 0.000 title claims abstract description 11
- 238000000605 extraction Methods 0.000 title abstract description 9
- 238000010793 Steam injection (oil industry) Methods 0.000 claims abstract description 92
- 238000004519 manufacturing process Methods 0.000 claims abstract description 22
- 238000007599 discharging Methods 0.000 claims abstract description 20
- 239000007788 liquid Substances 0.000 claims abstract description 9
- 230000009977 dual effect Effects 0.000 claims description 44
- 238000010438 heat treatment Methods 0.000 claims description 33
- 238000011084 recovery Methods 0.000 claims description 29
- 239000003921 oil Substances 0.000 abstract description 65
- 239000010779 crude oil Substances 0.000 abstract description 9
- 238000004891 communication Methods 0.000 abstract description 3
- 238000002360 preparation method Methods 0.000 abstract description 3
- 238000001514 detection method Methods 0.000 description 4
- 230000001351 cycling effect Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
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- 238000005516 engineering process Methods 0.000 description 2
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Abstract
The invention provides a preheating method before oil extraction by double horizontal wells and an oil extraction method by double horizontal wells, wherein the preheating method before oil extraction by double horizontal wells comprises the following steps: and injecting steam into a first steam injection pipe and a second steam injection pipe which are respectively arranged in the steam injection well and in the production well, and discharging underground liquid through a first liquid discharge pipe arranged in the steam injection well and a second liquid discharge pipe arranged in the production well, so that the communication degree between the steam injection well and the production well reaches a preset value. The preheating method before oil extraction of the double horizontal wells comprises the steps of simultaneously injecting steam into an oil layer by utilizing a first steam injection pipe arranged in a steam injection well and a second steam injection pipe arranged in a production well so as to heat the oil layer, determining whether production preparation is made for the double horizontal wells or not by detecting the communication degree between the steam injection well and the production well, fully preheating the oil layer by the double horizontal wells so that the oil layer has good production conditions, and then performing oil extraction production so as to obtain higher crude oil yield.
Description
Technical field
The present invention relates to oil exploitation technology, in particular to the pre-heating mean before the oil recovery of a kind of dual horizontal well and dual horizontal well oil production method.
Background technology
Dual horizontal well oil production method is the oil-extraction method of a kind of applicable heavy crude producing, the method can be passed through steam injection well and discharge steam with heating in crude oil layer to crude oil layer, make crude oil fluidization gradually, again through being arranged on the producing well of steam injection downhole by the oil extraction of fluidization out, thus realizing the high-efficiency mining to viscous crude.
Before dual horizontal well recovers the oil, need to first pass through steam injection well and oil reservoir is preheated by producing well, to improve the connectedness between steam injection well and producing well, so that steam can form vapor chamber smoothly crude oil presses to producing well with heating in crude oil layer, but in carrying out actual production, the effect of this preheating is also bad, and after preheating, the connected ratio between steam injection well and producing well is lower than 35%, and after therefore proceeding to production stage, crude oil yield becomes negatively affected.
Summary of the invention
Present invention is primarily targeted at the pre-heating mean before providing a kind of dual horizontal well to recover the oil and dual horizontal well oil production method, bad to solve the warm effect before carrying out dual horizontal well oil recovery of the prior art, that connected ratio between steam injection well and producing well is low problem.
To achieve these goals, according to an aspect of the present invention, provide the pre-heating mean before a kind of dual horizontal well recovers the oil, including: inject steam to the first steam injection pipe being separately positioned in steam injection well and the second steam injection pipe being arranged in producing well, and the liquid of down-hole is gone out by the first discharging tube being arranged in steam injection well and the second discharge opeing bank of tubes being arranged in producing well so that the connecting degree between steam injection well and producing well reaches preset value.
Further, the connecting degree between steam injection well and producing well is more than or equal to 70%.
Further, the down-hole pressure of steam injection well and producing well is controlled lower than oil reservoir fracture pressure 0.5MPa to 1.0MPa.
Further, the pre-heating mean before dual horizontal well oil recovery includes: S01: injects steam to the first steam injection pipe and the second steam injection pipe, and is gone out the liquid of down-hole by the first discharging tube and the second discharge opeing bank of tubes；S02: simultaneously raise the down-hole pressure of steam injection well and producing well, and control the down-hole pressure of steam injection well and producing well lower than oil reservoir fracture pressure 0.5MPa to 1.0MPa；S03: make the down-hole pressure down-hole pressure more than producing well of steam injection well, the connecting degree between detection steam injection well and producing well, stops preheating and starts to produce when connecting degree reaches preset value.
Further, in S02 step, control the down-hole pressure difference of steam injection well and producing well less than or equal to 0.2MPa.
Further, in S03 step, the down-hole pressure controlling steam injection well is between 0.2MPa to 0.3MPa more than the pressure differential of the down-hole pressure of producing well.
Further, in S03 step, close the first discharging tube.
Further, in the process carrying out S01 step, when the end that steam arrives steam injection well and producing well being detected, stop S01 step, start S02 step.
Further, in the process carrying out S02 step, when linkage change occurs in the pressure detected between steam injection well and producing well, stop S02 step, start S03 step.
According to another aspect of the present invention, additionally providing a kind of dual horizontal well oil production method, including before carrying out oil recovery and producing, oil reservoir is preheated, oil reservoir is preheated by the pre-heating mean before the dual horizontal well oil recovery that the employing of dual horizontal well oil production method is above-mentioned.
Application technical scheme, pre-heating mean before dual horizontal well oil recovery utilizes the first steam injection pipe being arranged in steam injection well and the second steam injection pipe being arranged in producing well to inject steam in oil reservoir simultaneously, to heat oil reservoir, and by the connecting degree between detection steam injection well and producing well to determine whether dual horizontal well has carried out Operational preparation, oil reservoir has been carried out preheating fully by dual horizontal well, oil reservoir is made to have possessed good working condition, now carry out again recovering the oil producing, it becomes possible to obtain higher crude output.
Accompanying drawing explanation
The Figure of description constituting the part of the application is used for providing a further understanding of the present invention, and the schematic description and description of the present invention is used for explaining the present invention, is not intended that inappropriate limitation of the present invention.In the accompanying drawings:
Fig. 1 illustrates the schematic diagram of the pipeline break-make situation in the pit shaft warm-up phase of the embodiment of the pre-heating mean before the dual horizontal well oil recovery according to the present invention, balanced pressure-raising stage or Steady pressure cycling stage；And
Fig. 2 illustrates the schematic diagram of the pipeline break-make situation in the minute-pressure draining stage of the embodiment of the pre-heating mean before the dual horizontal well oil recovery according to the present invention.
Accompanying drawing labelling in figure: 10, steam injection well；11, the first steam injection pipe；12, the first discharging tube；20, producing well；21, the second steam injection pipe；22, the second discharging tube.
Detailed description of the invention
It should be noted that when not conflicting, the embodiment in the application and the feature in embodiment can be mutually combined.Describe the present invention below with reference to the accompanying drawings and in conjunction with the embodiments in detail.
According to an aspect of the present invention, provide the pre-heating mean before a kind of dual horizontal well recovers the oil, including: inject steam to the first steam injection pipe 11 being separately positioned in steam injection well 10 and the second steam injection pipe 21 being arranged in producing well 20, and the liquid of down-hole is discharged by the first discharging tube 12 being arranged in steam injection well 10 and the second discharging tube 22 being arranged in producing well 20 so that the connecting degree of steam injection well 10 and producing well 20 reaches preset value.
Pre-heating mean before the dual horizontal well oil recovery of the present invention utilizes the first steam injection pipe 11 being arranged in steam injection well 10 and the second steam injection pipe 21 being arranged in producing well 20 to inject steam in oil reservoir simultaneously, to heat oil reservoir, and by the connecting degree between detection steam injection well 10 and producing well 20 to determine whether dual horizontal well has carried out Operational preparation, such as, when the connected ratio when between steam injection well 10 and producing well 20 reaches 75%, represent dual horizontal well to have carried out preheating fully to oil reservoir, oil reservoir is made to have possessed good working condition, now carry out again recovering the oil producing, just it is obtained in that higher crude output.
The structure of the dual horizontal well of the pre-heating mean of the application present invention is as depicted in figs. 1 and 2, steam injection well 10 is arranged on the top of producing well 20, it is provided with the first steam injection pipe 11 being positioned below and the first discharging tube 12 above in steam injection well 10, in producing well 20, is provided with the second steam injection pipe 21 being positioned below and the second discharging tube 22 above.It should be noted that the first steam injection pipe 11 and the second steam injection pipe 21 extend to steam injection well 10 and the end of producing well 20 respectively, the length of the first discharging tube 12 and the second discharging tube 22 is then shorter than the first steam injection pipe 11 and the second steam injection pipe 21.
Preferably, the connecting degree between steam injection well 10 and producing well 20 is more than or equal to 70%.Steam injection well 10 offers multiple vapor opening, same producing well 20 also offers multiple inlet opening accordingly, and linkage between connecting degree and each inlet opening and the corresponding vapor opening between steam injection well 10 and producing well 20, can be formed, namely vapor opening discharges steam, then inlet opening begins with crude oil entrance.Namely connecting degree represents more than or equal to 70% and has more than between the inlet opening of 70% and corresponding vapor opening and define linkage.
Preferably, the down-hole pressure of steam injection well 10 and producing well 20 is controlled lower than oil reservoir fracture pressure 0.5MPa to 1.0MPa.In order to avoid in warm, down-hole pressure is excessive and destroy oil reservoir, it is therefore desirable to down-hole pressure is controlled accordingly.
Preferably, the pre-heating mean before dual horizontal well oil recovery includes: S01: injects steam to the first steam injection pipe 11 and the second steam injection pipe 21, and is discharged the liquid of down-hole by the first discharging tube 12 and the second discharging tube 22；S02: simultaneously raise the down-hole pressure of steam injection well 10 and producing well 20, and control the down-hole pressure of steam injection well 10 and producing well 20 lower than oil reservoir fracture pressure 0.5MPa to 1.0MPa；S03: make the down-hole pressure down-hole pressure more than producing well 20 of steam injection well 10, the connecting degree between detection steam injection well 10 and producing well 20, stops preheating and starts to produce when connecting degree reaches preset value.
S01 step is pit shaft warm-up phase, and the break-make situation of this stage each pipeline is as it is shown in figure 1, its object is to preheating pit shaft, it is achieved Uniform Horizontal Well heating oil reservoir.In the process carrying out S01 step, when the end that steam arrives steam injection well 10 and producing well 20 being detected, stop S01 step, start S02 step.
S02 step is the balanced pressure-raising stage, and the break-make situation of this stage each pipeline, as it is shown in figure 1, its object is to improve the down-hole pressure of steam injection well 10 and producing well 20 simultaneously, improves downhole temperature, expands heating radius, shorten preheating time.In S02 step, control the down-hole pressure difference of steam injection well 10 and producing well 20 less than or equal to 0.2MPa.
After the process carrying out S02 step, after down-hole pressure is raised to preset value, for instance during lower than oil reservoir fracture pressure 0.5MPa, keep this pressure, oil reservoir is carried out continuous heating, and now pre-heating mean enters the Steady pressure cycling stage, and the break-make situation of this stage each pipeline is as shown in Figure 1.When linkage change occurs in the pressure detected between steam injection well 10 and producing well 20, stop Steady pressure cycling, start S03 step.
S03 step is the minute-pressure draining stage, and namely the break-make situation of this stage each pipeline as in figure 2 it is shown, promote crude oil circulation between well, to test the step of connecting degree.In S03 step, the down-hole pressure controlling steam injection well 10 is between 0.2MPa to 0.3MPa more than the pressure differential of the down-hole pressure of producing well 20.It is highly preferred that in S03 step, the down-hole pressure controlling steam injection well 10 is 0.3MPa more than the pressure differential of the down-hole pressure of producing well 20.If detecting, interwell communication rate reaches 70%, namely proceeds by oil recovery and produces.
Preferably, in S03 step, close the first discharging tube 12.To obtain the connected ratio data of more elegant.
Adopting the pre-heating mean before the dual horizontal well oil recovery of the present invention, the connected ratio that preheating terminates between rear well on average can reach more than 85%, and ratio improves nearly 51% in prior art, therefore improve the yield of subsequent manufacturing steps.
According to another aspect of the present invention, additionally providing a kind of dual horizontal well oil production method, including before carrying out oil recovery and producing, oil reservoir is preheated, oil reservoir is preheated by the pre-heating mean before the dual horizontal well oil recovery that the employing of dual horizontal well oil production method is above-mentioned.
Because the connected ratio that the pre-heating mean before the dual horizontal well oil recovery of the present invention enables between steam injection well 10 and producing well 20 significantly raises, therefore oil recovery process can be more smooth, and produce well yield also to be improved, adopt the dual horizontal well oil production method of the present invention, the yield at oil recovery initial stage can reach every day 15 tons, and ratio improves more than 5 tons in prior art.
The foregoing is only the preferred embodiments of the present invention, be not limited to the present invention, for a person skilled in the art, the present invention can have various modifications and variations.All within the spirit and principles in the present invention, any amendment of making, equivalent replacement, improvement etc., should be included within protection scope of the present invention.
Claims (10)
1. the pre-heating mean before a dual horizontal well oil recovery, it is characterized in that, including: inject steam to the first steam injection pipe (11) being separately positioned in steam injection well (10) and the second steam injection pipe (21) being arranged in producing well (20), and by be arranged on the first discharging tube (12) in described steam injection well (10) and be arranged in described producing well (20) the second discharging tube (22) discharge down-hole liquid so that the connecting degree between described steam injection well (10) and described producing well (20) reaches preset value.
2. the pre-heating mean before dual horizontal well according to claim 1 oil recovery, it is characterised in that the connecting degree between described steam injection well (10) and described producing well (20) is more than or equal to 70%.
3. the pre-heating mean before dual horizontal well according to claim 1 oil recovery, it is characterised in that control the down-hole pressure of described steam injection well (10) and described producing well (20) lower than oil reservoir fracture pressure 0.5MPa to 1.0MPa.
4. the pre-heating mean before dual horizontal well according to claim 1 oil recovery, it is characterised in that the pre-heating mean before the oil recovery of described dual horizontal well includes:
S01: inject steam to described first steam injection pipe (11) and described second steam injection pipe (21), and discharged the liquid of down-hole by described first discharging tube (12) and described second discharging tube (22)；
S02: simultaneously raise described steam injection well (10) and the down-hole pressure of described producing well (20), and control the down-hole pressure of described steam injection well (10) and described producing well (20) lower than oil reservoir fracture pressure 0.5MPa to 1.0MPa；
S03: make the down-hole pressure down-hole pressure more than described producing well (20) of described steam injection well (10), detect the connecting degree between described steam injection well (10) and described producing well (20), stop preheating when described connecting degree reaches preset value and start to produce.
5. the pre-heating mean before dual horizontal well according to claim 4 oil recovery, it is characterised in that in S02 step, control the down-hole pressure difference of described steam injection well (10) and described producing well (20) less than or equal to 0.2MPa.
6. the pre-heating mean before dual horizontal well according to claim 4 oil recovery, it is characterized in that, in S03 step, the down-hole pressure controlling described steam injection well (10) is between 0.2MPa to 0.3MPa more than the pressure differential of the down-hole pressure of described producing well (20).
7. the pre-heating mean before dual horizontal well according to claim 4 oil recovery, it is characterised in that in S03 step, close described first discharging tube (12).
8. the pre-heating mean before dual horizontal well according to claim 4 oil recovery, it is characterized in that, in the process carrying out S01 step, when the end that steam arrives described steam injection well (10) and described producing well (20) being detected, stop S01 step, start S02 step.
9. the pre-heating mean before dual horizontal well according to claim 4 oil recovery, it is characterized in that, in the process carrying out S02 step, when there is linkage change in the pressure detected between described steam injection well (10) and described producing well (20), stop S02 step, start S03 step.
10. a dual horizontal well oil production method, including before carrying out oil recovery and producing, oil reservoir is preheated, it is characterised in that described oil reservoir is preheated by the pre-heating mean before described dual horizontal well oil production method employing dual horizontal well oil recovery according to any one of claim 1 to 9.
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| CN201410790805.0A CN105756644B (en) | 2014-12-17 | 2014-12-17 | Preheating method before oil extraction of double horizontal wells and oil extraction method of double horizontal wells |
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| CN201410790805.0A CN105756644B (en) | 2014-12-17 | 2014-12-17 | Preheating method before oil extraction of double horizontal wells and oil extraction method of double horizontal wells |
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| CN105756644B CN105756644B (en) | 2018-09-04 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN106593376A (en) * | 2016-12-15 | 2017-04-26 | 中国石油天然气股份有限公司 | Artificial foam oil hair promoter and heavy oil reservoir displacement exploitation method after steam flooding |
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| CN103615225A (en) * | 2013-11-28 | 2014-03-05 | 中国石油天然气股份有限公司 | Double-horizontal-well isothermal difference forced steam circulation preheating method for middle-deep layer oil reservoir |
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2014
- 2014-12-17 CN CN201410790805.0A patent/CN105756644B/en active Active
Patent Citations (6)
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| US20050082067A1 (en) * | 1999-10-26 | 2005-04-21 | Good William K. | Process for sequentially applying SAGD to adjacent sections of a petroleum reservoir |
| US20070175638A1 (en) * | 2006-02-01 | 2007-08-02 | Crichlow Henry B | Petroleum Extraction from Hydrocarbon Formations |
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| CN103615225A (en) * | 2013-11-28 | 2014-03-05 | 中国石油天然气股份有限公司 | Double-horizontal-well isothermal difference forced steam circulation preheating method for middle-deep layer oil reservoir |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106593376A (en) * | 2016-12-15 | 2017-04-26 | 中国石油天然气股份有限公司 | Artificial foam oil hair promoter and heavy oil reservoir displacement exploitation method after steam flooding |
| CN106593376B (en) * | 2016-12-15 | 2019-06-11 | 中国石油天然气股份有限公司 | Artificial foam oil hair promoter and heavy oil reservoir displacement exploitation method after steam flooding |
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