CN101949283A - Water reducing, de-plugging and yield increasing integrated process - Google Patents

Abstract

The invention provides a water reducing, de-plugging and yield increasing integrated process. The process comprises the following steps of: (1) washing wells by using diesel or activated water; (2) performing a water plugging process; (3) isolating by using 32 percent of solution of potassium chloride; (4) performing a de-plugging process, and replacing by using clean water; (5) performing a well shutdown reaction for 4 to 24 hours, and opening the wells for drainage; and (6) recovering normal production. The process has the advantages of high process success rate, safe and reliable construction and obvious effect.

Description

A kind of diminishing plugging removal and stimulation integral process

Technical field

The present invention relates to the yield-increasing technique in a kind of oil field development, specifically a kind of diminishing plugging removal and stimulation integral process.

Background technology

China all takes in most of oil fields the mode of waterflooding extraction, oil reservoir type complexity in addition, reservoir heterogeneity is serious, and short, the strata pressure of perforated interval and profit frontier distance reduces in addition, form pressure drop funnel around the straight well pit shaft, cause containing the water surface and rise, waterflood injection rate is excessive, reasons such as cementing quality, make water breakthrough early, rate of water cut increase is fast, and Bian Shui, end water water-coning phenomena appear in some well, produce invalid water filling.

To be end water advance to epicone (ridge) the formation mechanism of water awl mainly is because due to the pressure that produces during oil well production fell, promptly in recovery process, the oil reservoir bottom had formed direction and has been bordering on vertical barometric gradient, so just makes end water move upward.Continue when producing exploitation, oil-water interfaces constantly raise to the height of the vertex of a cone.When the gravitational difference that causes greater than the profit density contrast falls in oil well production formation pressure, bore the life of setting out.Because the density of water is bigger than oil, when water was bored rising, hydrostatic pressure rose, and in certain output scope, the water awl becomes stable, and at this moment appearance is moisture in the oil well, and water is bored and become unstable, and water is just broken through in well, reaches a kind of new pressure balance.Thereby cause well water many, form invalid water filling.

The meaning of profile control and water plugging work is very important, its objective is the output of control oil-field brine, keeps stratum energy.Because of oil reservoir is inhomogeneous, have high permeability zone and in, less permeable layer, when water flood recovery, the water always high permeability zone of longshore current dynamic resistance minimum is charged into oil well, produces higher waterflood recovery efficiency factor, and involve less than in, less permeable layer, so waterflood recovery efficiency factor is not high.As time goes on, water washes away high permeability zone, forms the extra-high-speed permeable formation.At this moment, water invalid circulation in the loop of flood pattern, oil reservoir and sewerage treatment and re-injection system formation, waterflood recovery efficiency factor has just no longer improved.Therefore, must from water injection well or these high permeability zones of oil well plugging and extra-high-speed permeable formation force the water of injection enter oil saturation high, less permeable layer, to reach the purpose that improves oil recovery factor.

It should be noted that transfer drive technology has two key problem in technology, the one, must with the viscosity of the preferred displacing agent of rock core, omit water-front advance velocity according to permeability faster than new water-entering interval to guarantee the profile control agent fltting speed; The 2nd, reduce the injury of enhancement Layer when clamp-oning profile control agent as far as possible, injection pressure must be greater than the startup pressure reduction of profile control interval, less than the startup pressure reduction of strengthening interval.Rock core (or artificial simulation rock core) actual measurement can be used in this two aspect.Oilwell water shutoff also has similar problem, because it is limited to stop up radius, units increased in production and period of validity are all very little, so concerning the porosity oil reservoir, unless holostrome water logging otherwise should not adopt the water blockoff measure to certain interval water outlet in the layer.And,, can only utilize the non-homogeneity in this class oil field to carry out water blockoff at oil well owing to can't adjust at well to block Fractured Reservoir with Bottom Water, begin large fracture is blocked, though like this exhalant canal is blocked, the while also blocks the oil discharge passage of some gaps, so effect is also undesirable.Develop into the blocking agent of infiltrative stifled large fracture later on, effect makes moderate progress.

But because the displacement pressure reduction of sillar system is very big, permeability decrease is very big in the large fracture, and filtrational resistance is bigger, and pressure is suppressed higherly in the large fracture, can not form big displacement pressure reduction, and the oil in the sillar system still can't get out.

Summary of the invention

The objective of the invention is to avoid the deficiencies in the prior art and a kind of diminishing plugging removal and stimulation integral process is provided.

Technical scheme of the present invention is: a kind of diminishing plugging removal and stimulation integral process, and step is: (1) uses diesel oil or active water well-flushing; (2) implement water-plugging technology; (3) use 32% Klorvess Liquid to isolate; (4) carry out de-plugging process, replace clear water; (5) the closing well reaction is 4-24 hour, and anti-row drives a well; (6) return to normal production.

Step (2) water-plugging technology is for adding water shutoff agent in tubing string, water shutoff agent is that percentage is that the setting accelerator of 0.2-0.3%, crosslinking agent, the percentage that percentage is 0.3-0.4% are the gel-type blocking agent or the granular pattern blocking agent of the various ionic type polyacrylamides of 0.1-0.5% or the emulsion polyacrylamide mixing formation that percentage is the various ionic types of 0.1-0.6%.

Step (4) de-plugging process is for adding de-plugging agent, and de-plugging agent is that percentage is that 10% compound acid, sandstone acid or bionic acid and percentage are that 1% depolymerizing agent solution mixes.

Water shutoff agent is the consumption of well treatment radius 1.5m, and 32% potassium chloride insulating liquid is the consumption of well treatment radius 0.5m, and de-plugging agent is the consumption of well treatment radius 1m, and plug water construction needs blocking agent to be calculated as follows:

$V=\mathrm{\π}\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{r}_2\×h_i\×{\mathrm{\φ}}_i$

In the formula: V---water shutoff agent consumption, m ³

Ri---the treatment radius of i interval, m selects 1.5 herein;

Hi---the thickness of i interval, m;

φ i---the effecive porosity of i interval, decimal.

Technical scheme of the present invention also has: before step (1) is implemented, carry out the fixed tubular column construction, carry out sleeve pipe by the completion flow string and instead squeeze.

Technical scheme of the present invention can also be: before step (1) is implemented, trip out down-hole pipe, roofbolt, logical thorn is checked following operating tool string.

Compared with prior art, advantage of the present invention has: technology success rate height, and construction safety is reliable, and effect is remarkable.Can adjust the intake profile on water filling stratum by plugging agent, the exhalant canal that shutoff is big, the sealing ratiod height, simple to operate.Can open the gap of oil flow channel and shutoff by injecting acid and gel breaker, improve water plugging effect, oil well productivity is improved greatly.

It is big that this technology is suitable for interlayer permeability difference, and interlayer or interlayer are thin, and production profile, intake profile are unclear, or cementing quality difference and cause the oil-water well of scurrying groove.But want the consumption of strict control blocking agent and acid solution, the water outlet duct can't block, too much can produce bigger injury to oil reservoir again when plug agent amount was very few, and the very few injury that can't handle blocking agent to less permeable layer of acid solution too much may cause water plugging effect undesirable again.

Description of drawings

Fig. 1 is mechanism of action figure of the present invention.

Wherein a is that the water taper becomes because penetrate in-place permeability difference, strata pressure reduces, and waterflood injection rate is excessive etc., and reason causes that well water rises, water outlet increases, and forms the water awl, forms invalid water filling.

B injects blocking agent, by injecting water shutoff agent the water outlet duct of high permeability zone is blocked, blocking agent progresses into the deep, duct, and progressively forms obstruction near wellbore zone and less permeable layer surface, the fuel-displaced duct of part that might block simultaneously causes not water outlet of oil well also not fuel-displaced.

C injects acid and gel breaker by injecting acid and gel breaker solution, and near wellbore zone and less permeable layer because the obstruction that water blockoff causes is removed, are improved the less permeable layer matrix permeability by acidifying simultaneously, makes the oil flow channel increase, the raising oil production.

D is the anti-row that drives a well.

The specific embodiment

The invention discloses a kind of oilfield diminishing plugging removal and stimulation integral process that is used for, the steps include: (1) use diesel oil or active water well-flushing; (2) implement water-plugging technology; (3) use 32% Klorvess Liquid to isolate; (4) carry out de-plugging process, replace clear water; (5) the closing well reaction is 4-24 hour, and anti-row drives a well; (6) return to normal production.Before step (1) is implemented, carry out the fixed tubular column construction, carry out sleeve pipe by the completion flow string and instead squeeze.Before step (1) is implemented, trip out down-hole pipe, roofbolt, logical thorn is checked following operating tool string.Described step (2) water-plugging technology is for adding water shutoff agent in tubing string, water shutoff agent is that percentage is that the setting accelerator of 0.2-0.3%, crosslinking agent, the percentage that percentage is 0.3-0.4% are the gel-type blocking agent or the granular pattern blocking agent of the various ionic type polyacrylamides of 0.1-0.5% or the emulsion polyacrylamide mixing formation that percentage is the various ionic types of 0.1-0.6%.Described step (4) de-plugging process is for adding de-plugging agent, and de-plugging agent is that percentage is that 10% compound acid, sandstone acid or bionic acid and percentage are that 1% depolymerizing agent solution mixes.Described water shutoff agent is the consumption of well treatment radius 1.5m, and 32% potassium chloride insulating liquid is the consumption of well treatment radius 0.5m, and de-plugging agent is the consumption of well treatment radius 1m, and plug water construction needs blocking agent to be calculated as follows:

$V=\mathrm{\π}\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{r}_2\×h_i\×{\mathrm{\φ}}_i$

In the formula: V---water shutoff agent consumption, m ³

Ri---the treatment radius of i interval, m selects 1.5 herein;

Hi---the thickness of i interval, m;

φ i---the effecive porosity of i interval, decimal.

Technical scheme of the present invention is: at first use diesel oil or active water well-flushing, implement water-plugging technology, use clear water to replace, carry out de-plugging process again, the anti-row that at last de-plugging liquid driven a well returns to normal production.Technology of the present invention is carried out well-flushing by using hot diesel oil or active water, and the organic deposition of removing in the pit shaft stops up, and reduces the pressure of follow-up injection medicament; Inject water shutoff agent and can adjust the intake profile on water filling stratum more fully, the exhalant canal that shutoff is big, eliminate invalid water filling, by a certain amount of de-plugging medicament of follow-up injection, less permeable layer sweep efficiency in the enhancing, improve matrix permeability, improve oil well productivity, reach the effect of oil well production increasing, energy efficiency.

Below in conjunction with embodiment the present invention is done and to be described in detail:

Embodiment one:

Carry out the fixed tubular column construction, carry out sleeve pipe by present completion flow string and instead squeeze, at first use hot diesel oil well-flushing, inject 0.5% PAMA dry powder+0.2% setting accelerator+0.4% cross-linking agent solution 450m ³After, use the 150m32% Klorvess Liquid to isolate, to wherein injecting 10% compound acid+1% oxidant gel breaker solution 300m3, replace clear water 20m again ³, after 8 hours, the anti-row that drives a well returns to normal production.

Embodiment two:

Carry out the fixed tubular column construction, carrying out sleeve pipe by present completion flow string instead squeezes, at first use the active water well-flushing, after injecting 0.6% emulsion polyacrylamide+0.3% setting accelerator+0.3% cross-linking agent solution 600m3, use the 200m32% Klorvess Liquid to isolate, to wherein injecting 10% sandstone acid+1% depolymerizing agent solution 400m3, replace clear water 30m again ³, after 4 hours, the anti-row that drives a well returns to normal production.

Embodiment three:

Carry out the fixed tubular column construction, carry out sleeve pipe by present completion flow string and instead squeeze, at first use hot diesel oil well-flushing, inject granular pattern blocking agent 300m ³After, use the 100m32% Klorvess Liquid to isolate, again to wherein injecting 10% bionic acid+1% oxidant gel breaker solution 200m ³, replace clear water 20m ³, after 12 hours, the anti-row that drives a well returns to normal production.

Embodiment four:

Trip out down-hole pipe, roofbolt, logical thorn checks that following operating tool string at first uses the active water well-flushing, clamp-ons gel-type water shutoff agent 400m from operating tool string ³, use the 150m32% Klorvess Liquid to isolate, again to wherein injecting 10% bionic acid+1% oxidant gel breaker solution 270m ³, replace clear water, closing well reaction 24 hours, anti-row, following flow string returns to normal production.

Claims (6)

1. a diminishing plugging removal and stimulation integral process is characterized in that step is: (1) use diesel oil or active water well-flushing; (2) implement water-plugging technology; (3) use 32% Klorvess Liquid to isolate; (4) carry out de-plugging process, replace clear water; (5) the closing well reaction is 4-24 hour, and anti-row drives a well; (6) return to normal production.

2. a kind of diminishing plugging removal and stimulation integral process according to claim 1, it is characterized in that step (1) is implemented before, carry out the fixed tubular column construction, carry out sleeve pipe by the completion flow string and instead squeeze.

3. a kind of diminishing plugging removal and stimulation integral process according to claim 1, it is characterized in that step (1) is implemented before, trip out down-hole pipe, roofbolt, logical thorn is checked following operating tool string.

4. a kind of diminishing plugging removal and stimulation integral process according to claim 1, it is characterized in that described step (2) water-plugging technology for add water shutoff agent in tubing string, water shutoff agent is that percentage is that the setting accelerator of 0.2-0.3%, crosslinking agent, the percentage that percentage is 0.3-0.4% are the gel-type blocking agent or the granular pattern blocking agent of the various ionic type polyacrylamides of 0.1-0.5% or the emulsion polyacrylamide mixing formation that percentage is the various ionic types of 0.1-0.6%.

5. a kind of diminishing plugging removal and stimulation integral process according to claim 1, it is characterized in that described step (4) de-plugging process for adding de-plugging agent, de-plugging agent is that percentage is that 10% compound acid, sandstone acid or bionic acid and percentage are that 1% depolymerizing agent solution mixes.

6. a kind of diminishing plugging removal and stimulation integral process according to claim 1, it is characterized in that water shutoff agent is the consumption of well treatment radius 1.5m, 32% potassium chloride insulating liquid is the consumption of well treatment radius 0.5m, de-plugging agent is the consumption of well treatment radius 1m, and plug water construction needs blocking agent to be calculated as follows:

$V=\mathrm{\π}\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{r}_2\×h_i\×{\mathrm{\φ}}_i$

In the formula: V---water shutoff agent consumption, m ³

Ri---the treatment radius of i interval, m selects 1.5 herein;

Hi---the thickness of i interval, m;

φ i---the effecive porosity of i interval, decimal.

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