CN108843281A - A kind of calculation method of column plunger lift drain efficiency - Google Patents
A kind of calculation method of column plunger lift drain efficiency Download PDFInfo
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- CN108843281A CN108843281A CN201810564941.6A CN201810564941A CN108843281A CN 108843281 A CN108843281 A CN 108843281A CN 201810564941 A CN201810564941 A CN 201810564941A CN 108843281 A CN108843281 A CN 108843281A
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- 238000004364 calculation method Methods 0.000 title claims abstract description 16
- 239000007788 liquid Substances 0.000 claims abstract description 34
- 241000521257 Hydrops Species 0.000 claims abstract description 25
- 206010030113 Oedema Diseases 0.000 claims abstract description 25
- 238000000034 method Methods 0.000 claims abstract description 21
- 238000005259 measurement Methods 0.000 claims abstract description 9
- 239000012530 fluid Substances 0.000 claims description 9
- 230000001133 acceleration Effects 0.000 claims description 3
- 238000004458 analytical method Methods 0.000 claims description 3
- 230000005484 gravity Effects 0.000 claims description 3
- 239000007789 gas Substances 0.000 description 22
- 238000011084 recovery Methods 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 238000005457 optimization Methods 0.000 description 2
- 238000005086 pumping Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 230000007423 decrease Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 230000002045 lasting effect Effects 0.000 description 1
- 239000003345 natural gas Substances 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
- E21B43/12—Methods or apparatus for controlling the flow of the obtained fluid to or in wells
- E21B43/121—Lifting well fluids
- E21B43/122—Gas lift
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B47/00—Survey of boreholes or wells
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B47/00—Survey of boreholes or wells
- E21B47/007—Measuring stresses in a pipe string or casing
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B47/00—Survey of boreholes or wells
- E21B47/06—Measuring temperature or pressure
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B51/00—Testing machines, pumps, or pumping installations
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06Q—INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR
- G06Q50/00—Information and communication technology [ICT] specially adapted for implementation of business processes of specific business sectors, e.g. utilities or tourism
- G06Q50/02—Agriculture; Fishing; Forestry; Mining
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Abstract
The invention discloses a kind of calculation methods of column plunger lift drain efficiency, include the following steps：1) the well mouth oil pipe pressure P to be driven a well when lifting by wellhead pressure sensor measurementtubAnd casing pressure Pcas, and device depth L is located according to shaft bottom and calculates hydrops liquid-column height h in the preceding oil pipe of lifting；2) the driving pressure differential deltap P of plunger starting moment is calculated；3) measurement plunger is run to time t used in ground；4) the average speed v of Plunger Lift is calculatedp；5) plunger lift leaking liquid amount computation model is established, the average leaked flow Q of lifting process liquid is then calculatedleak；6) the Plunger Lift average speed v that hydrops liquid-column height h, step 4) obtain in oil pipe before the lifting obtained according to step 1)pAnd the average leaked flow Q of lifting process liquid that step 5) obtainsleakPlunger lift drain efficiency eta is calculated, this method can be realized accurately calculating for plunger lift drain efficiency.
Description
Technical field
The invention belongs to plunger lift drainage gas recovery fields, are related to a kind of calculating of column plunger lift drain efficiency
Method.
Background technique
In the lasting recovery process of natural gas resource, with the reduction of gas reservoir pressure, gas cannot be by the liquid in pit shaft
Body continuously carries out well head, forms shaft bottom hydrops, and the increase of shaft bottom hydrops can reduce gas well yield or even make the complete stop-spraying of gas well.
Technique of plunger gas lift is as the higher water pumping gas production method of economy, using movable plunger in shape between gas and liquid two phases in pit shaft
At solid interface, to enhance gas-liquid sealing, water pumping gas production efficiency is improved.For column plunger, to guarantee column plunger in well
The flexibility moved in cylinder, certainly exists gap between column plunger and tube inner wall face, can flow through gap by lifting hydrops and produce
Raw liquid is fallen after rise, to cause the decline of plunger lift drain efficiency.Also, different column piston structures and operation controlling party
Method will affect plunger lift drain efficiency.But since condition limits, most of oil gas field scenes are difficult to realize to individual well hydrops
The metering of amount and lifting lifting rate, so that plunger lift drain efficiency is difficult to accurately calculate.Therefore, it is necessary to a kind of column plunger gas
The calculation method of drain efficiency is lifted, is also piston structure choosing to realize the quantitative calculating to column plunger lift drain efficiency
Type and method of controlling operation thereof optimization provide reference frame.
Summary of the invention
It is an object of the invention to overcome the above-mentioned prior art, a kind of column plunger lift drain efficiency is provided
Calculation method, this method can be realized accurately calculating for plunger lift drain efficiency.
In order to achieve the above objectives, the calculation method of column plunger lift drain efficiency of the present invention includes following step
Suddenly：
1) the well mouth oil pipe pressure P to be driven a well when lifting by wellhead pressure sensor measurementtubAnd casing pressure Pcas, and root
Device depth L, which is located, according to shaft bottom calculates hydrops liquid-column height h in the preceding oil pipe of lifting；
2) well mouth oil pipe pressure P when being lifted according to driving a well of obtaining of step 1)tub, casing pressure Pcas, lift before in oil pipe
Hydrops liquid-column height h and shaft bottom are located the driving pressure differential deltap P that device depth L calculates plunger starting moment；
3) measurement plunger is run to time t used in ground；
4) device depth L is located according to shaft bottom and plunger that step 3) obtains runs to time t used in ground and calculates plunger
The average speed v of liftingp；
5) it chooses plunger and fluid column is that control volume carries out force analysis, establish plunger lift leaking liquid amount computation model, then
The driving pressure differential deltap P of the plunger starting moment obtained according to plunger lift leaking liquid amount computation model and step 2) calculates lifting process
The average leaked flow Q of liquidleak；
6) Plunger Lift that hydrops liquid-column height h, step 4) obtain in oil pipe before the lifting obtained according to step 1) is average
Speed vpAnd the average leaked flow Q of lifting process liquid that step 5) obtainsleakCalculate plunger lift drain efficiency eta.
Hydrops liquid-column height h is in oil pipe in step 1)：
Wherein, ρlFor hydrops density, g is acceleration of gravity.
The driving pressure differential deltap P of plunger starting moment is in step 2)：
Δ P=Pcas(1+1.879×10-6L1.5)-Ptub[1+1.879×10-6(L-h)1.5] (2)。
The average speed v of Plunger Lift in step 4)pFor：
The average leaked flow Q of lifting process liquids in step 5)leakFor：
Wherein, D is pipe aperture, FrleakFor leakage froude number.
Leakage froude number FrleakFor：
Wherein, FrlFor fluid column froude number, RelFor liquid Reynolds number, Eu is starting Euler's numbers, FrgFor gas Fu Lude
Number, ρgGas density at device is located for shaft bottom.
Fluid column froude number FrlFor：
Liquid reynolds number RelFor：
Starting Euler's numbers Eu is：
Gas froude number FrgFor：
Wherein, μlFor hydrops viscosity, MgGas mass flow is produced for gas well.
Plunger gas lift liquid drainage efficiency eta is in step 6)：
The invention has the advantages that：
The calculation method of column plunger lift drain efficiency of the present invention need to only utilize gas well well when specific operation
Mouthful pressure sensor measurement drives a well well mouth oil pipe pressure and casing pressure when lifting, then according to this based on calculate separately plunger and open
Move the driving pressure differential deltap P of moment, the average speed v of Plunger LiftpAnd the average leaked flow Q of lifting process liquidleak, then
Plunger lift drain efficiency eta is calculated according to the above-mentioned parameter being calculated, it is simple, convenient, to realize plunger lift drain
Efficiency eta accurately calculates, and in actual operation, when η is closer to 1, then column plunger lift process liquids leakage rate is smaller, from well
Discharge hydrops is more in cylinder, and drain efficiency is higher, evaluation and optimization tool to plunger lift drainage gas recovery in industrial practice
There is important directive significance.
Detailed description of the invention
Fig. 1 is the distribution map of pressure sensor in the present invention；
Fig. 2 is plunger lift parameter schematic diagram in the present invention.
Specific embodiment
The invention will be described in further detail with reference to the accompanying drawing：
With reference to Fig. 1, the calculation method of column plunger lift drain efficiency, which is characterized in that include the following steps：
1) the well mouth oil pipe pressure P to be driven a well when lifting by wellhead pressure sensor measurementtubAnd casing pressure Pcas, and root
Device depth L is located according to shaft bottom and calculates hydrops liquid-column height h in the preceding oil pipe of lifting, wherein hydrops liquid-column height h is in oil pipe：
Wherein, ρlFor hydrops density, g is acceleration of gravity.
2) well mouth oil pipe pressure P when being lifted according to driving a well of obtaining of step 1)tub, casing pressure Pcas, lift before in oil pipe
Hydrops liquid-column height h and shaft bottom are located the driving pressure differential deltap P that device depth L calculates plunger starting moment, wherein plunger starts moment
Driving pressure differential deltap P be：
Δ P=Pcas(1+1.879×10-6L1.5)-Ptub[1+1.879×10-6(L-h)1.5] (2)。
3) measurement plunger is run to time t used in ground；
4) device depth L is located according to shaft bottom and plunger that step 3) obtains runs to time t used in ground and calculates plunger
The average speed v of liftingp, wherein the average speed v of Plunger LiftpFor：
5) it chooses plunger and fluid column is that control volume carries out force analysis, establish plunger lift leaking liquid amount computation model, then
The driving pressure differential deltap P of the plunger starting moment obtained according to plunger lift leaking liquid amount computation model and step 2) calculates lifting process
The average leaked flow Q of liquidleak, wherein the average leaked flow Q of lifting process liquidleakFor：
Wherein, D is pipe aperture, FrleakFor leakage froude number；
Leakage froude number FrleakFor：
Wherein, FrlFor fluid column froude number, RelFor liquid Reynolds number, Eu is starting Euler's numbers, FrgFor gas Fu Lude
Number, ρgGas density at device is located for shaft bottom.
Fluid column froude number FrlExpression formula be：
Liquid reynolds number RelFor：
Starting Euler's numbers Eu is：
Gas froude number FrgFor：
Wherein, μlFor hydrops viscosity, MgGas mass flow is produced for gas well.
6) Plunger Lift that hydrops liquid-column height h, step 4) obtain in oil pipe before the lifting obtained according to step 1) is average
Speed vpAnd the average leaked flow Q of lifting process liquid that step 5) obtainsleakPlunger lift drain efficiency eta is calculated,
In, plunger lift drain efficiency eta is：
In actual operation, η is closer to 1, then column plunger lift process liquids leakage rate is smaller, and product is discharged from pit shaft
Liquid is more, and drain efficiency is higher.
Claims (8)
1. a kind of calculation method of column plunger lift drain efficiency, which is characterized in that include the following steps：
1) the well mouth oil pipe pressure P to be driven a well when lifting by wellhead pressure sensor measurementtubAnd casing pressure Pcas, and according to well
Bottom is located device depth L and calculates hydrops liquid-column height h in the preceding oil pipe of lifting；
2) well mouth oil pipe pressure P when being lifted according to driving a well of obtaining of step 1)tub, casing pressure Pcas, lift before hydrops in oil pipe
Liquid-column height h and shaft bottom are located the driving pressure differential deltap P that device depth L calculates plunger starting moment；
3) measurement plunger is run to time t used in ground；
4) device depth L is located according to shaft bottom and plunger that step 3) obtains runs to time t used in ground and calculates Plunger Lift
Average speed vp；
5) it chooses plunger and fluid column is that control volume carries out force analysis, establish plunger lift leaking liquid amount computation model, then basis
The driving pressure differential deltap P for the plunger starting moment that plunger lift leaking liquid amount computation model and step 2) obtain calculates lifting process liquid
Average leaked flow Qleak；
6) the Plunger Lift average speed v that hydrops liquid-column height h, step 4) obtain in oil pipe before the lifting obtained according to step 1)p
And the average leaked flow Q of lifting process liquid that step 5) obtainsleakCalculate plunger lift drain efficiency eta.
2. the calculation method of column plunger lift drain efficiency according to claim 1, which is characterized in that oily in step 1)
Hydrops liquid-column height h is in managing：
Wherein, ρlFor hydrops density, g is acceleration of gravity.
3. the calculation method of column plunger lift drain efficiency according to claim 1, which is characterized in that step 2) center pillar
Plug starting moment driving pressure differential deltap P be：
Δ P=Pcas(1+1.879×10-6L1.5)-Ptub[1+1.879×10-6(L-h)1.5] (2)。
4. the calculation method of column plunger lift drain efficiency according to claim 1, which is characterized in that step 4) center pillar
Fill in the average speed v of liftingpFor：
5. the calculation method of column plunger lift drain efficiency according to claim 1, which is characterized in that step 5) is passed the imperial examinations at the provincial level
Rise the average leaked flow Q of process liquidsleakFor：
Wherein, D is pipe aperture, FrleakFor leakage froude number.
6. the calculation method of column plunger lift drain efficiency according to claim 5, which is characterized in that leakage Fu Lude
Number FrleakFor：
Wherein, FrlFor fluid column froude number, RelFor liquid Reynolds number, Eu is starting Euler's numbers, FrgFor gas froude number, ρg
Gas density at device is located for shaft bottom.
7. the calculation method of column plunger lift drain efficiency according to claim 6, which is characterized in that fluid column Fu Lude
Number FrlFor：
Liquid reynolds number RelFor：
Starting Euler's numbers Eu is：
Gas froude number FrgFor：
Wherein, μlFor hydrops viscosity, MgGas mass flow is produced for gas well.
8. the calculation method of column plunger lift drain efficiency according to claim 1, which is characterized in that step 6) center pillar
Filling in gas lift liquid drainage efficiency eta is：
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| CN201810564941.6A CN108843281B (en) | 2018-06-04 | 2018-06-04 | Calculation method for columnar plunger gas lift liquid drainage efficiency |
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| CN201810564941.6A CN108843281B (en) | 2018-06-04 | 2018-06-04 | Calculation method for columnar plunger gas lift liquid drainage efficiency |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114427387A (en) * | 2020-09-25 | 2022-05-03 | 中国石油化工股份有限公司 | Calculation method for gas well plunger gas lift technological parameters |
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2018
- 2018-06-04 CN CN201810564941.6A patent/CN108843281B/en active Active
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| CN202152676U (en) * | 2011-06-01 | 2012-02-29 | 中国石油天然气股份有限公司 | Plunger device for online measurement of gas wells and plunger liquid discharging and gas production system |
| CN202596696U (en) * | 2012-04-05 | 2012-12-12 | 中国石油天然气股份有限公司 | Hollow rod one-way air lifting drainage gas production device |
| US20150167434A1 (en) * | 2013-12-18 | 2015-06-18 | Shell Oil Company | Downhole device for gas well deliquification |
| CN106570273A (en) * | 2016-11-04 | 2017-04-19 | 中国石油天然气股份有限公司 | Building method and application of three parameter-gas well drainage gas recovery technology optimizing model |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114427387A (en) * | 2020-09-25 | 2022-05-03 | 中国石油化工股份有限公司 | Calculation method for gas well plunger gas lift technological parameters |
| CN114427387B (en) * | 2020-09-25 | 2023-10-13 | 中国石油化工股份有限公司 | Calculation method of gas well plunger gas lift process parameters |
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