CN1766283A - Fracturing process in oil and water well by means of biological enzyme preparation - Google Patents
Fracturing process in oil and water well by means of biological enzyme preparation Download PDFInfo
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- CN1766283A CN1766283A CN 200510104560 CN200510104560A CN1766283A CN 1766283 A CN1766283 A CN 1766283A CN 200510104560 CN200510104560 CN 200510104560 CN 200510104560 A CN200510104560 A CN 200510104560A CN 1766283 A CN1766283 A CN 1766283A
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- Prior art keywords
- well
- oil
- biological enzyme
- fracturing fluid
- water
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- 102000004190 Enzymes Human genes 0.000 title claims abstract description 38
- 108090000790 Enzymes Proteins 0.000 title claims abstract description 38
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 32
- 238000000034 method Methods 0.000 title claims abstract description 17
- 230000008569 process Effects 0.000 title claims description 13
- 238000002360 preparation method Methods 0.000 title description 4
- 239000012530 fluid Substances 0.000 claims abstract description 42
- 239000003129 oil well Substances 0.000 claims abstract description 21
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 14
- 230000000694 effects Effects 0.000 claims abstract description 13
- 239000003795 chemical substances by application Substances 0.000 claims abstract description 11
- 239000007788 liquid Substances 0.000 claims abstract description 10
- 238000011084 recovery Methods 0.000 claims abstract description 10
- 239000002253 acid Substances 0.000 claims abstract description 9
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 7
- 239000003921 oil Substances 0.000 claims description 36
- 239000000203 mixture Substances 0.000 claims description 34
- 238000009472 formulation Methods 0.000 claims description 33
- 239000010779 crude oil Substances 0.000 claims description 12
- 239000011664 nicotinic acid Substances 0.000 claims description 7
- 230000035699 permeability Effects 0.000 claims description 5
- 239000011148 porous material Substances 0.000 claims description 5
- 239000011800 void material Substances 0.000 claims description 3
- 239000011435 rock Substances 0.000 abstract description 12
- 230000035515 penetration Effects 0.000 abstract 1
- 238000004901 spalling Methods 0.000 abstract 1
- 229940088598 enzyme Drugs 0.000 description 23
- 238000004519 manufacturing process Methods 0.000 description 6
- 238000004140 cleaning Methods 0.000 description 4
- 230000000638 stimulation Effects 0.000 description 4
- 108091005804 Peptidases Proteins 0.000 description 3
- 239000004365 Protease Substances 0.000 description 3
- 102100037486 Reverse transcriptase/ribonuclease H Human genes 0.000 description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 3
- 208000027418 Wounds and injury Diseases 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 3
- 150000001875 compounds Chemical class 0.000 description 3
- 230000006378 damage Effects 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 208000014674 injury Diseases 0.000 description 3
- 230000009467 reduction Effects 0.000 description 3
- 238000009736 wetting Methods 0.000 description 3
- 230000008901 benefit Effects 0.000 description 2
- 238000006073 displacement reaction Methods 0.000 description 2
- 238000000605 extraction Methods 0.000 description 2
- 239000004576 sand Substances 0.000 description 2
- 241000256844 Apis mellifera Species 0.000 description 1
- 241000894006 Bacteria Species 0.000 description 1
- 239000006004 Quartz sand Substances 0.000 description 1
- FEWJPZIEWOKRBE-UHFFFAOYSA-N Tartaric acid Natural products [H+].[H+].[O-]C(=O)C(O)C(O)C([O-])=O FEWJPZIEWOKRBE-UHFFFAOYSA-N 0.000 description 1
- 230000004913 activation Effects 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 238000000855 fermentation Methods 0.000 description 1
- 230000004151 fermentation Effects 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 229940059442 hemicellulase Drugs 0.000 description 1
- 108010002430 hemicellulase Proteins 0.000 description 1
- 238000005213 imbibition Methods 0.000 description 1
- 230000001939 inductive effect Effects 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 239000012528 membrane Substances 0.000 description 1
- 239000002120 nanofilm Substances 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 239000003208 petroleum Substances 0.000 description 1
- 238000012797 qualification Methods 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 238000012216 screening Methods 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 230000002269 spontaneous effect Effects 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
- 235000002906 tartaric acid Nutrition 0.000 description 1
- 239000011975 tartaric acid Substances 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- 230000010148 water-pollination Effects 0.000 description 1
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- Preparation Of Compounds By Using Micro-Organisms (AREA)
Abstract
The invention discloses an oil field oil-water well fracturing craft method of biological enzyme agent, which is characterized by the following: building the mixed biological enzyme agent and water or biological acid or antisludging agent or liquid nitrogen as fracturing fluid; forcing the fracturing fluid into the oil well or water well through the fracturing vehicle; pressing the fracturing fluid into the crack; opening the well after 72 hours. The biological enzyme agent penetrates the hole throat then enters into the microscopic hole gap, which attaches the rock surface and denudes the raw oil to improve the earth penetration factor. The method improves the water wet effect and washes the spalling oil film, which improves the recovery factor of raw oil.
Description
One, technical field
The present invention relates to carry out in the oil field development a kind of method of fracture in oil and water wells, specifically a kind of process of utilizing biological enzyme formulation to carry out the oilfield oil well pressure break.
Two, background technology
At present in order to improve the ultimate recovery in oil field, under developmently take a lot of well stimulations, wherein to improve the degree of porosity and the permeability of oil reservoir be one of main well stimulation to formation fracturing, and fracturing yield increasing method is feasible, but different fracturing technologies has different effects, different defectives is also arranged,, certain effect of increasing production is arranged as fracture acidizing, but it is bigger to the oil well pipe corrosion, reduce the application life of tubing and casing, the stratum has been caused cave in, caused old formation blockage; Pressure break squeeze the sand effect also can, but in quartz sand, have residual fracturing fluid, the time is long easily hardens, cause new obstruction, along with oil recovery pressure reduction increases gradually, crude oil also arrives the shaft bottom to the abrasive band, cause the shaft bottom to stop up, be extracted into ground with oil and cause collection transmission pipe network to stop up and collect the wearing and tearing of transfer device.
Three, summary of the invention
The purpose of this invention is to provide a kind of process of utilizing biological enzyme formulation to carry out the oilfield oil well pressure break.
Technical scheme of the present invention realizes in the following manner:
Biological enzyme formulation and water or bionic acid or antisludging agent or liquid nitrogen mixed be re-dubbed fracturing fluid, compress at normal temperatures in oil well or the well with fracturing unit truck, fracturing fluid presses off the stratum gradually, fracturing fluid progresses in the crack that presses off, drive a well after 72 hours, in the closing up of cracks process, biological enzyme formulation infiltrates pore throat, enters microscopic void, be adsorbed on the core top layer, degrade crude oil, improve in-place permeability, improve the water-wet effect, oil film is peeled off in cleaning, destroy wax molecular network structure, reduce oil water interfacial tension, improve oil recovery factor.
Fracturing fluid is the fracturing fluid that is mixed with by the biological enzyme formulation of 0.5-5% and water.
To be biological enzyme formulation and water add that in the ratio of 0.5-5% the bionic acid of 3-10% is mixed with fracturing fluid to fracturing fluid.
To be biological enzyme formulation and water add 5-30m in the ratio of 0.5-5% to fracturing fluid
3Liquid nitrogen be mixed with fracturing fluid.
To be biological enzyme formulation and water add the fracturing fluid that the 10mg/L-5000mg/L antisludging agent is mixed with in the ratio of 0.5-5% to fracturing fluid.
Utilize biological enzyme formulation to carry out the pressure break oil-water well compared with the prior art following advantage arranged:
(1) inject by high pressure, exciting stratum forms the crack, and medicament infiltrates the rock core pore throat in closing course;
(2) enter the microcosmic duct by inducing, be adsorbed on the rock core top layer, degrade crude oil, improve the hole and shout with spontaneous imbibition effect;
(3) rock wettability changes, and improves seepage flow efficient;
(4) reduce oil water interfacial tension;
(5) diffusion improves the water molecule activation energy;
(6) oil film is peeled off in cleaning, reduces the content of wax of crude oil, reduces viscosity of crude;
(7) improve the hole permeability, reduce displacement pressure, back production pressure;
(8) obvious from demulsification;
(9) high efficiency is not considered the anti-problem of arranging;
(10) stratum no sequel, the cleaning construction;
(11) easy and simple to handle, site operation equipment is simple;
(12) has remarkable advantages at low-permeability oil deposit;
(13) anti-row's biology enzyme solution can be recycled secondary and use the minimizing cost;
(14) needn't consider that clossing pressure is big, the problem that causes support particles to pulverize;
(15) effect is remarkable, and is good in economic efficiency.
Four, description of drawings
No accompanying drawing.
Five, the specific embodiment
For further disclosing technical scheme of the present invention, elaborate below by embodiment:
Process of the present invention is biological enzyme formulation and water or bionic acid or antisludging agent or liquid nitrogen to be mixed be re-dubbed fracturing fluid, compress at normal temperatures in oil well or the well with fracturing unit truck, fracturing fluid presses off the stratum gradually, fracturing fluid progresses in the crack that presses off, drive a well after 72 hours, in the closing up of cracks process, biological enzyme formulation infiltrates pore throat, enters microscopic void, be adsorbed on the core top layer, degrade crude oil, improve in-place permeability, improve the water-wet effect, oil film is peeled off in cleaning, destroy wax molecular network structure, reduce oil water interfacial tension, improve oil recovery factor.
The reservoir rock surface wettability is divided into that oil is wet, water wet and is middle wetting, the wetting state on reservoir rock surface has very big influence to crude oil flow, the oil wettability rock is strong to the adhesion of crude oil, and water membrane is easily formed on the surface of hydrophily rock, has weakened the adhesion to crude oil.
Biological enzyme formulation is as a kind of water-soluble products, it can make the reservoir rock wettability of the surface transform to the wet direction of water from oil is wet, thereby change the wetting state of reservoir rock, reduce the interfacial tension between oil-rock stratum, make crude oil be easy to strip down from rock surface, the agent of biology enzyme volume increase simultaneously also has certain viscosity reduction effect, thereby has reduced the flow resistance of crude oil in formation pore.Under the effect of strata pressure, crude oil easily from around flow to pit shaft, play increase oil effect.
Biological enzyme formulation is when quickening displacement oil stream, form the effective molecular film structure of one deck on the oil reservoir top layer, oil reservoir is played the effect that prevents once more dirt deposition, anti-sealing injury, so comprehensive function improves greatly, effectively raise water injection capacity, recovery ratio is improved.And have the reduction petroleum sand carrying property, reduce the friction of fluid and sandstone, thereby reach stable.
1, biology enzyme fractured well selection principle
(1) selects the well that skin factor is higher, the oil reservoir injury weighs.Skin factor is tried to achieve by build-up analysis.
(2) choose the well lower than liquid-producing capacity.Be meant the ratio of present production fluid amount and honeybee value production fluid amount than liquid-producing capacity, this ratio is low more, and the pressure break measure may be effective more.
(3) choose the lower well of water-oil factor.Water-oil factor is lower, and fractured well is potential more.
(4) choose the well that the individual well recovery ratio is a block overall recovery factor average.If the individual well recovery ratio is very low, illustrate that the oil reservoir grade is very poor; If this value is very high, illustrate that oil well does not need the pressure break measure; If the very approaching oil of this value drives average, the most suitable pressure break of this well.
(5) choose well that never carried out the secondary well stimulation or the well that never carried out well stimulation in 5 years in the past.
2, the qualifications of screening fractured well
(1) block of enforcement pressure break should be in the ripe water drive stage, guarantees to have reached stabilization of fluidized.
(2) reservoir pressure should be on bubble point pressure.Only in this way, in most cases gassiness saturated concentration and gas compressibility factor can be ignored.
(3) fractured well of Xuan Zeing should have stable production history, so that the calculation stability daily oil production.
3, embodiment
(1) if the serious oil well of oil reservoir injury, is pressed onto fracturing fluid in the stratum with fracturing unit truck than being 1% to add that the fracturing fluid that 5% bionic acid is mixed with carries out pressure break with pure biological enzyme formulation and water, closing well normally drove a well after 72 hours after the pressure break, without discharge opeing.
(2) if the lower oil well of water-oil factor is 3% to add 10m with pure biological enzyme formulation and water ratio
3The fracturing fluid of liquid nitrogen preparation carry out pressure break, with fracturing unit truck fracturing fluid is pressed onto in the stratum, the intact back of pressure break closing well normally drove a well after 72 hours, without discharge opeing.
(3) if than the low oil well of liquid-producing capacity, with biological enzyme formulation and water ratio is that 2% fracturing fluid of preparing carries out pressure break, with fracturing unit truck fracturing fluid is pressed onto in the stratum, after pressure break is intact, the fracturing fluid of closing well anti-oil extraction tubing string after 72 hours, counter being discharged in the jar in order to using again next time.
(4) if high-water-cut oil-producing well or well add that in 5% ratio the fracturing fluid of 100mg/L preparation carries out pressure break with biological enzyme formulation and water, with fracturing unit truck fracturing fluid is pressed onto in the stratum, closing well drove a well after 72 hours after the pressure break, fracturing fluid that need not anti-oil extraction tubing string.
Bionic acid: the acid that utilizes bioprocess technology to refine, as the tartaric acid of fermentation generation.
Biological enzyme formulation: contain preparation with the biology enzyme composition.As: protease, hemicellulase compound formulation; Protease, bacterium, bioactivator compound formulation; Protease, biological antisludging agent compound formulation.
Claims (5)
1, a kind of process of utilizing biological enzyme formulation to carry out the oilfield oil well pressure break, biological enzyme formulation and water or bionic acid or antisludging agent or liquid nitrogen mixed be re-dubbed fracturing fluid, compress at normal temperatures in oil well or the well with fracturing unit truck, fracturing fluid presses off the stratum gradually, fracturing fluid progresses in the crack that presses off, and drives a well after 72 hours, in the closing up of cracks process, biological enzyme formulation infiltrates pore throat, enter microscopic void, be adsorbed on the core top layer, degrade crude oil, improve in-place permeability, improve the water-wet effect, clean and peel off oil film, destroy wax molecular network structure, reduce oil water interfacial tension, improve oil recovery factor.
2, the process of utilizing biological enzyme formulation to carry out the oilfield oil well pressure break according to claim 1, it is characterized in that described fracturing fluid is the fracturing fluid that biological enzyme formulation and water by 0.5-5% are mixed with, compress at normal temperatures in oil well or the well with fracturing unit truck, drive a well after 72 hours.
3, the process of utilizing biological enzyme formulation to carry out the oilfield oil well pressure break according to claim 1, it is characterized in that described fracturing fluid is biological enzyme formulation and water and adds that in the ratio of 0.5-5% the bionic acid of 3-10% is mixed with fracturing fluid, compress at normal temperatures in oil well or the well with fracturing unit truck, drive a well after 72 hours.
4, the process of utilizing biological enzyme formulation to carry out the oilfield oil well pressure break according to claim 1 is characterized in that described fracturing fluid is biological enzyme formulation and water and adds 5-30m in the ratio of 0.5-5%
3Liquid nitrogen be mixed with fracturing fluid, compress at normal temperatures in oil well or the well with fracturing unit truck, drive a well after 72 hours.
5, the process of utilizing biological enzyme formulation to carry out the oilfield oil well pressure break according to claim 1, it is characterized in that described fracturing fluid is biological enzyme formulation and water and adds the fracturing fluid that the 10mg/L-5000mg/L antisludging agent is mixed with in the ratio of 0.5-5%, compress at normal temperatures in oil well or the well with fracturing unit truck, drive a well after 72 hours.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200510104560 CN1766283A (en) | 2005-11-12 | 2005-11-12 | Fracturing process in oil and water well by means of biological enzyme preparation |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200510104560 CN1766283A (en) | 2005-11-12 | 2005-11-12 | Fracturing process in oil and water well by means of biological enzyme preparation |
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| Publication Number | Publication Date |
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| CN1766283A true CN1766283A (en) | 2006-05-03 |
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| CN 200510104560 Pending CN1766283A (en) | 2005-11-12 | 2005-11-12 | Fracturing process in oil and water well by means of biological enzyme preparation |
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101629074A (en) * | 2009-06-30 | 2010-01-20 | 东营盛世石油科技有限责任公司 | Formulation for preparing fracturing fluid from biological enzyme preparation |
| CN101629486A (en) * | 2009-06-30 | 2010-01-20 | 东营盛世石油科技有限责任公司 | Clean fracturing flowback fluid recovery, oil displacement and blockage removal process |
| CN101638981A (en) * | 2009-06-30 | 2010-02-03 | 东营盛世石油科技有限责任公司 | Bio-enzyme fracturing outlet liquid recovering, oil-displacing and de-plugging process |
| CN101838620B (en) * | 2009-03-17 | 2012-04-18 | 大连百奥泰科技有限公司 | A strain of Bacillus subtilis and an alkali-resistant and salt-resistant oilfield fracturing enzyme and its application |
| CN102493795A (en) * | 2011-11-15 | 2012-06-13 | 燕山大学 | Method for gasification fracturing of liquid nitrogen in hydrocarbon reservoirs |
| CN105973679A (en) * | 2016-07-19 | 2016-09-28 | 东北石油大学 | Method for manufacturing artificial fracture core |
| CN110219629A (en) * | 2010-06-23 | 2019-09-10 | 伊科普罗有限责任公司 | Hydraulic fracturing |
| CN112324418A (en) * | 2020-11-30 | 2021-02-05 | 中国石油集团渤海钻探工程有限公司 | Hydraulic breaking process for underground rock |
-
2005
- 2005-11-12 CN CN 200510104560 patent/CN1766283A/en active Pending
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101838620B (en) * | 2009-03-17 | 2012-04-18 | 大连百奥泰科技有限公司 | A strain of Bacillus subtilis and an alkali-resistant and salt-resistant oilfield fracturing enzyme and its application |
| CN101629074A (en) * | 2009-06-30 | 2010-01-20 | 东营盛世石油科技有限责任公司 | Formulation for preparing fracturing fluid from biological enzyme preparation |
| CN101629486A (en) * | 2009-06-30 | 2010-01-20 | 东营盛世石油科技有限责任公司 | Clean fracturing flowback fluid recovery, oil displacement and blockage removal process |
| CN101638981A (en) * | 2009-06-30 | 2010-02-03 | 东营盛世石油科技有限责任公司 | Bio-enzyme fracturing outlet liquid recovering, oil-displacing and de-plugging process |
| CN110219629A (en) * | 2010-06-23 | 2019-09-10 | 伊科普罗有限责任公司 | Hydraulic fracturing |
| CN110219629B (en) * | 2010-06-23 | 2021-12-03 | 伊科普罗有限责任公司 | Hydraulic fracturing |
| CN102493795A (en) * | 2011-11-15 | 2012-06-13 | 燕山大学 | Method for gasification fracturing of liquid nitrogen in hydrocarbon reservoirs |
| CN105973679A (en) * | 2016-07-19 | 2016-09-28 | 东北石油大学 | Method for manufacturing artificial fracture core |
| CN105973679B (en) * | 2016-07-19 | 2018-11-16 | 东北石油大学 | A kind of man-made fracture Corestone manufacture method |
| CN112324418A (en) * | 2020-11-30 | 2021-02-05 | 中国石油集团渤海钻探工程有限公司 | Hydraulic breaking process for underground rock |
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