CN101265406A - Pad acid liquid and pad acid sand fracturing method - Google Patents
Pad acid liquid and pad acid sand fracturing method Download PDFInfo
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- CN101265406A CN101265406A CNA2008101062298A CN200810106229A CN101265406A CN 101265406 A CN101265406 A CN 101265406A CN A2008101062298 A CNA2008101062298 A CN A2008101062298A CN 200810106229 A CN200810106229 A CN 200810106229A CN 101265406 A CN101265406 A CN 101265406A
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Abstract
The invention relates to a front acid liquid, which is applied to the oil well front acid sand fracturing. The invention is characterized in that the front acid liquid comprises the components by the weight percentages as follows: chlorhydric acid 1.0 to 2.0 percent; acetic acid 4.0 to 8.0 percent; formic acid 1.0 to 2.0 percent; CF-5C 0.4 to 0.7 percent; citric acid 0.08 to 0.12 percent; HJF-94 0.95 to 1.15 percent; COP-1 0.3 to 0.5 percent; clean water for the other. Through the front acid sand fracturing processing of the invention, the connectedness between the container rock and the crevasse and between the inner parts of the crevasses can be improved, therefore the connectedness between the container rock and the mineshaft, and the fracturing can be enhanced to improve the effect of the oil well.
Description
Technical field
The present invention relates to oil-field development borehole operation technical field, particularly a kind of wellfracturing technology is the preposition sour sandfrac technology that improves per-well production.
Background technology
At present, oil well adopts matrix acidifying can remove the immediate vicinity of wellbore pollution, improves reservoir and pit shaft connectedness, is an important immediate vicinity of wellbore de-plugging and well stimulation of sandstone oil reservoir.Because the even corrosion rock of acid solution is difficult to form effective flow conductivity after the crack closure, the transformation that sandstone reservoir enforcement acid fracturing pressure technology is used for the low infiltration sandrock oil reservoir is difficult to obtain to improve the effect of per-well production.Therefore, the sandstone acidizing acid fracturing generally is used for the immediate vicinity of wellbore de-plugging, and the single employing acidifying of low infiltration sandrock oil reservoir ACID FRACTURING TECHNOLOGY effect of increasing production is not obvious.
For the low infiltration sandrock oil reservoir, the waterpower sandfrac can form long supporting crack, has high flow conductivity, is conventional at present renovation technique.But the broken glue effect of the crosslinked guanidine glue of waterfrac treatment is not thorough, and the fracturing liquid filter cake of formation has lowered the percolation ability between stratum and the supporting crack, and the cull in the supporting crack has reduced fissured flow conductivity, thereby has influenced production capacity.
In recent years, reduce various to stratum, supporting crack injury that fracturing liquid cull and residue cause, the connectedness between raising stratum and the crack becomes an important research direction of tackling key problems in the hydraulic fracturing technology field.
Summary of the invention
The objective of the invention is: a kind of preposition sour sandfrac method is provided,, improves near the perviousness on stratum, reservoir crack by sour karst erosion reaction; Preposition acid solution effectively suppresses swelling clay mineral; Residual acid is at the row's of returning stage dissolving part fracturing liquid filter cake and crack wall cull; The Degradation of residual acid of fracturing fluid recovery (backflow) stage improves broken glue degree; The fracturing fluid recovery (backflow) stage, supporting crack was cleaned in residual acid.By preposition sour corrosion and Degradation improve in the supporting crack and and reservoir between connectedness, thereby reach the raising per-well production.
The technical solution used in the present invention is: preposition sour sandfrac method is that matrix acidifying and sandfrac are gathered a technology that forms, creatively proposed to add earlier the technical thought of acid back pressure break, utilize the corrosion of preposition acid and Degradation improve in the supporting crack and and reservoir between connectedness, improve per-well production.
The gordian technique of preposition sour sandfrac method:
1. preposition sour acid fluid system is preferred: acid fluid system preferably can not be identical with acidifying acid fracturing in the past, because preposition sour SAND FRACTURING TECHNOLOGY not only will be considered acid solution and rock level of response factor, also will consider the influence to factors such as later stage pressure break, discharge opeings.Given this, at present domestic do not have codes and standards to use, and the method for preposition sour formula optimization needs research.
2. preposition acid solution consumption, the optimization of injecting discharge capacity: this research is the same, and at present domestic some theoretical and methods that do not form can be used for reference, and preposition acid solution consumption, the isoparametric optimization of injection discharge capacity need be considered more multifactor.
Preposition acid solution formulation components:
Each weight percentages of components of preposition acid solution: hydrochloric acid, 1.0～2.0%; Acetate, 4.0～8.0%; Formic acid, 1.0～2.0%; CF-5C, 0.4～0.7%; Citric acid, 0.08～0.12%; HJF-94,0.95～1.15%; COP-1,0.3～0.5%; All the other are clear water.
CF-5C is that a kind of compound helping squeezed, and major ingredient is a tensio-active agent.CF-5C not only has good reduction oil water interfacial tension ability, and has stronger anti-newborn breakdown of emulsion ability, is mainly used in oil field compression fracture, the acidizing treatment and reaches anti-newborn breakdown of emulsion to reduce oil water interfacial tension, significantly improves drain age velocity, reduces reservoir damage.The long celebrating oilfield chemical production and sales CF-5C of Group Co.,Ltd product.
HJF-94 can be by forming the absorption protective membrane at the metallic surface oriented adsorption; also can suppress acid and intermetallic electrode reaction simultaneously; be applicable to the interaction of multiple corrosive medium, the unidirectional corrosion of ionic and multielement and comprehensive corrosion that produces and the corrosive environment of depositing, the corrosive environment of concentrated hydrochloric acid is had good against corrosion, resistance erosion, corrosion inhibition.The inhibition that is applicable to industrial equipmentss such as acidification of oil gas well operation, refinery, power station, boiler and pipe network is anticorrosion.The long celebrating oilfield chemical production and sales HJF-94 of Group Co.,Ltd product.
COP-1 is a kind of molecular weight at 300～800 oligopolymer, surface of clay is had high affinity, has overcome the shortcoming that macrocation stops up pore throat, and the hole injury is little, and anti-swollen effect is obvious.Be suitable for hyposmosis, extra-low permeability hydrocarbon zone.The long celebrating oilfield chemical production and sales COP-1 of Group Co.,Ltd product.
Preposition sour sandfrac method is achieved in that
A, preposition acid solution process for preparation:
Prepare acidproof jar and clear water, in acidproof jar, add the configuration material by weight percentage, under the normal temperature and pressure situation, stir, obtain preposition acid solution.
B, preposition sour SAND FRACTURING TECHNOLOGY process are:
Base fluid low for → preposition acid is low replace → to set → preposition acid fracturing splits → spacer pad → frozen glue sandfrac → closing well, open flow.Preposition sour SAND FRACTURING TECHNOLOGY process and existing SAND FRACTURING TECHNOLOGY process are basic identical, difference be base fluid is low replace after, before setting, the low process of replacing of preposition acid is arranged.
The first step: base fluid is low to be replaced: start pump, inject melon matrix liquid 3～4m by oil pipe
3, replace original liquid in the pit shaft with melon matrix liquid.Pump duty is at 0.5m
3/ min.
Second step: preposition acid is low to be replaced: inject preposition acid solution 3～4m by oil pipe
3, discharge capacity is at 0.5m
3/ min.Melon matrix liquid returns to the pkr bottom, can not cause the pkr acid etching.
The 3rd step: improve the discharge capacity packer setting: improve pumping rate, reach pumping rate between 0.5～1.0, down-hole packer is set.
The 4th step: preposition acid fracturing splits: improve discharge capacity, reach 1.4～1.6m
3Between/the min.Preposition acid solution is injected 15～20m
3Between.
The 5th step: inject spacer pad: inject spacer pad 2m
3Spacer pad adopts melon matrix liquid.
The 6th step: injection adds sand frozen glue: injection adds sand frozen glue 100～150m
3Between.Pump pressure is 25～35) between.Between time 60～90min.
The 7th step: closing well, open flow: after closing well built the pressure 0.5 hour, open flow drove a well.Big discharge capacity open flow discharge opeing makes full use of the Degradation and the cleanup action of the residual acid of the row of returning.
Optimize the acid solution consumption and annotate sour discharge capacity, should be economical, abundant again sour rock reaction enlarges the pore throat radius, and guarantees that residual acid concentration returns row's dissolving etc. of degrading in the stage.
Beneficial effect of the present invention: preposition sour sandfrac technology is by improving the connectedness between reservoir and crack and the inside, crack, thereby improved the connectedness between reservoir and the pit shaft, improved the fracturing reform effect.
This technology thoroughly or has significantly been degraded on the rock wall, the fracturing liquid cull in the supporting crack, dissolved impurity in fracturing liquid filter cake and the crack largely, and rock pore throat radius has reduced trigger pressure near having enlarged the crack, thereby improved the connectedness between stratum and crack and the inside, crack, reduce the crude oil flow resistance, improved per-well production.
Embodiment
Embodiment 1: with white 216 districts, the preposition sour sandfrac of Yuan25-20Jing is an example, is elaborated.
White 216 districts, Yuan25-20Jing carry out each weight percentages of components of preposition acid solution of preposition sour sandfrac: hydrochloric acid, 1.0%; Acetate, 6.0%; Formic acid, 2.0%; CF-5C, 0.5%; Citric acid, 0.1%; HJF-94,1.0%; COP-1,0.3%; All the other are clear water.Prepared 21m
3Standby.
White 216 districts, Yuan25-20Jing use preposition acid solution and carry out preposition sour sandfrac process:
A, preposition acid solution process for preparation:
Prepare acidproof jar and clear water, in acidproof jar, add the configuration material by weight percentage, under the normal temperature and pressure situation, stir, obtain preposition acid solution.
B, preposition sour SAND FRACTURING TECHNOLOGY process are:
Base fluid low for → preposition acid is low replace → to set → preposition acid fracturing splits → spacer pad → frozen glue sandfrac → closing well, open flow
The first step: base fluid is low to be replaced: start pump, inject melon matrix liquid 3.5m3 by oil pipe, replace original liquid in the pit shaft with melon matrix liquid.Pump duty is at 0.5m3/min.Melon matrix liquid is prior art.
Second step: preposition acid is low to be replaced: inject preposition acid solution 3.5m by oil pipe
3, discharge capacity is at 0.5m
3/ min.Melon matrix liquid returns to the pkr bottom, can not cause the pkr acid etching.
The 3rd step: improve the discharge capacity packer setting: improve pumping rate, reaching pumping rate is 0.8m
3/ min sets down-hole packer.
The 4th step: preposition acid fracturing splits: improve discharge capacity, reach 1.5m
3/ min.Preposition acid solution is injected 18m
3
The 5th step: inject spacer pad: inject spacer pad 2m
3Spacer pad adopts melon matrix liquid.
The 6th step: injection adds sand frozen glue: injection adds sand frozen glue 120m
3Pump pressure is at 33MPa.Time 70min.
The 7th step: closing well, open flow: after closing well built the pressure 0.5 hour, open flow drove a well.
In nearly 2 years test, improving and apply, selected 9 blocks such as town 53, west 205, main road ditch, Ma Jiashan, fort gulf, white 209, white 216, Hou Bei and Bai 157 to carry out 160 mouthfuls of wells of test in place, integral body has obtained tests effect of increasing production preferably.The operation initial stage, town's 53 long 8 test pit individual wells increase that oily 1.9t/d, west 205 long 8 test pit individual wells increase oily 0.6t/d, the long 6 test pit individual wells of main road ditch increase oily 0.4t/d, white 216 long 6 test pit individual wells increase oily 0.42t/d by nearly 1 year trace analysis, about 5,000 ten thousand yuan of 160 mouthfuls of well cumulative rises profits.This technology has become the important technology that oil-field development improves per-well production, and chink content height, reservoir reconstruction that throat radius is little are had certain reference.
Embodiment 2: embodiment 2 with the difference of embodiment 1 is: each weight percentages of components of preposition acid solution: hydrochloric acid, 1.4%; Acetate, 7.0%; Formic acid, 1.5%; CF-5C, 0.6%; Citric acid, 0.11%; HJF-94,1.1%; COP-1,0.3%; All the other are clear water.
Preposition acid solution preparation and the preposition sour SAND FRACTURING TECHNOLOGY process of embodiment 2 are substantially the same manner as Example 1.
Embodiment 3: embodiment 3 with the difference of embodiment 1 is: each weight percentages of components of preposition acid solution of preposition sour sandfrac: hydrochloric acid, 1.5%; Acetate, 5.0%; Formic acid, 1.8%; CF-5C, 0.6%; Citric acid, 0.11%; HJF-94,0.95%; COP-1,0.3%; All the other are clear water.
Preposition acid solution preparation and the preposition sour SAND FRACTURING TECHNOLOGY process of embodiment 3 are substantially the same manner as Example 1.
Each weight percentages of components of embodiment 4-7
| Component | Embodiment 4 % | Embodiment 5 % | Embodiment 6 % | Embodiment 7 % |
| Hydrochloric acid | 1 | 2 | 2 | 1.5 |
| Acetate | 7.5 | 4.5 | 6 | 8 |
| Formic acid | 1.2 | 2 | 2 | 1 |
| CF-5C | 0.4 | 0.5 | 0.55 | 0.45 |
| Citric acid | 0.09 | 0.11 | 0.1 | 0.095 |
| HJF-94 | 0.96 | 0.11 | 1.05 | 1.0 |
| COP-1 | 0.4 | 0.42 | 0.35 | 0.45 |
| Clear water | Surplus | Surplus | Surplus | Surplus |
Effect of increasing production
16 mouthfuls of wells of the preposition sour sandfrac test in white 216 wellblocks, test pit spreads all over whole wellblock, compares with contiguous conventional sandfrac well, the results are shown in following table.
White 216 long 6 preposition sour sandfrac test pit and offset well data sheet
By contrast as can be seen, under the close situation of reservoir condition, preposition sour sandfrac well examination row output is higher than conventional sandfrac well.
Preposition sour SAND FRACTURING TECHNOLOGY effect of increasing production is obvious, and operation initial test well individual well daily output innage goes out conventional well 0.42t.
Claims (2)
1, a kind of preposition acid solution that is used for preposition sour sandfrac is characterized in that: each weight percentages of components: hydrochloric acid, 1.0～2.0%; Acetate, 4.0～8.0%; Formic acid, 1.0～2.0%; CF-5C, 0.4～0.7%; Citric acid, 0.08～0.12%; HJF-94,0.95～1.15%; COP-1,0.3～0.5%; All the other are clear water.
2, a kind of preposition sour sandfrac method is characterized in that:
A, preposition acid solution process for preparation:
Prepare acidproof jar, in acidproof jar, press claim 1 described preposition acid solution each component weight percent and add material, under the normal temperature and pressure situation, stir, obtain preposition acid solution;
B, preposition sour SAND FRACTURING TECHNOLOGY process are:
Base fluid low for → preposition acid is low replace → to set → preposition acid fracturing splits → spacer pad → frozen glue sandfrac → closing well, open flow
The first step: base fluid is low to be replaced: start pump, inject melon matrix liquid 3～4m by oil pipe
3, replacing original liquid in the pit shaft with melon matrix liquid, pump duty is at 0.5m
3/ min;
Second step: preposition acid is low to be replaced: inject preposition acid solution 3～4m by oil pipe
3, discharge capacity is at 0.5m
3/ min, melon matrix liquid returns to the pkr bottom, can not cause the pkr acid etching;
The 3rd step: improve the discharge capacity packer setting: improve pumping rate, reach pumping rate at 0.5～1.0m
3Between/the min, down-hole packer is set;
The 4th step: preposition acid fracturing splits: improve discharge capacity, reach 1.4～1.6m
3Between/the min; Preposition acid solution is injected 15～20m
3Between;
The 5th step: inject spacer pad: inject spacer pad 2m
3, spacer pad adopts melon matrix liquid;
The 6th step: injection adds sand frozen glue: injection adds sand frozen glue 100～150m
3Between, pump pressure is between 25～35MPa, between time 60～90min;
The 7th step: closing well, open flow: after closing well built the pressure 0.5 hour, the open flow that drives a well, big discharge capacity open flow discharge opeing makes full use of the Degradation and the cleanup action of the residual acid of the row of returning.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2008101062298A CN100549126C (en) | 2008-05-09 | 2008-05-09 | Preposition acid solution and preposition sour sandfrac method |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2008101062298A CN100549126C (en) | 2008-05-09 | 2008-05-09 | Preposition acid solution and preposition sour sandfrac method |
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| Publication Number | Publication Date |
|---|---|
| CN101265406A true CN101265406A (en) | 2008-09-17 |
| CN100549126C CN100549126C (en) | 2009-10-14 |
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| CN102220861A (en) * | 2011-05-06 | 2011-10-19 | 中国石油天然气股份有限公司 | Acid esters coordination directional glue crushing method |
| CN102321458A (en) * | 2011-06-01 | 2012-01-18 | 西南石油大学 | Isolating liquid for front acid sand fracturing and preparation method thereof |
| CN102877820A (en) * | 2011-07-15 | 2013-01-16 | 中国石油天然气股份有限公司 | Method for reducing water injection pressure of reservoir well |
| CN103982169A (en) * | 2014-04-29 | 2014-08-13 | 惠建龙 | Polybasic jelly acid sand carrying seam-adjustable acid fracturing method |
| CN104263339A (en) * | 2014-10-10 | 2015-01-07 | 克拉玛依市金鑫科技有限公司 | Oil-based drilling fluid shaft completion cleaning fluid and preparation method thereof |
| CN104747158A (en) * | 2015-02-05 | 2015-07-01 | 中国石油集团川庆钻探工程有限公司长庆井下技术作业公司 | Method for improving highly argillaceous sandstone layer |
| CN105715242A (en) * | 2014-08-12 | 2016-06-29 | 成都能生材科技开发有限责任公司 | Nanometer fracturing technology characterized by sand-free ultralow-temperature supercooling cold-shrinkage and thermal-expansion fracture generation |
| CN105822279A (en) * | 2015-01-05 | 2016-08-03 | 中国石油天然气股份有限公司 | Fracturing method and system |
| CN112983386A (en) * | 2021-02-25 | 2021-06-18 | 中国石油天然气股份有限公司 | Method and device for determining dosage of pad fluid |
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| CN102220861A (en) * | 2011-05-06 | 2011-10-19 | 中国石油天然气股份有限公司 | Acid esters coordination directional glue crushing method |
| CN102321458A (en) * | 2011-06-01 | 2012-01-18 | 西南石油大学 | Isolating liquid for front acid sand fracturing and preparation method thereof |
| CN102321458B (en) * | 2011-06-01 | 2013-11-13 | 西南石油大学 | Isolating liquid for front acid sand fracturing and preparation method thereof |
| CN102877820A (en) * | 2011-07-15 | 2013-01-16 | 中国石油天然气股份有限公司 | Method for reducing water injection pressure of reservoir well |
| CN103982169A (en) * | 2014-04-29 | 2014-08-13 | 惠建龙 | Polybasic jelly acid sand carrying seam-adjustable acid fracturing method |
| CN103982169B (en) * | 2014-04-29 | 2016-08-31 | 惠建龙 | Sand adjustable slit height acidifying fracturing process is taken in polynary frozen glue acid |
| CN105715242A (en) * | 2014-08-12 | 2016-06-29 | 成都能生材科技开发有限责任公司 | Nanometer fracturing technology characterized by sand-free ultralow-temperature supercooling cold-shrinkage and thermal-expansion fracture generation |
| CN105715242B (en) * | 2014-08-12 | 2019-01-29 | 成都能生材科技开发有限责任公司仁寿分公司 | Sand ultralow temperature supercooling cold shrinkage and thermal expansion seam nanometer fracturing technique is not added |
| CN104263339A (en) * | 2014-10-10 | 2015-01-07 | 克拉玛依市金鑫科技有限公司 | Oil-based drilling fluid shaft completion cleaning fluid and preparation method thereof |
| CN105822279A (en) * | 2015-01-05 | 2016-08-03 | 中国石油天然气股份有限公司 | Fracturing method and system |
| CN104747158A (en) * | 2015-02-05 | 2015-07-01 | 中国石油集团川庆钻探工程有限公司长庆井下技术作业公司 | Method for improving highly argillaceous sandstone layer |
| CN112983386A (en) * | 2021-02-25 | 2021-06-18 | 中国石油天然气股份有限公司 | Method and device for determining dosage of pad fluid |
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