The specific embodiment:
Specifically describe the present invention below in conjunction with practical operation.
In practical operation and implementing, the inventor realizes what bottom water reservoir was administered as follows, that is:
1. the classification of oil well
Initial water content according to oil well can be divided three classes oil well:
I class oil well: the initial stage moisture low (moisture content is less than 30%), and moisture content rose to production time of 80% greater than 150 days.Such oil well is typical bottom water reservoir development well, also is to have the oil well of administering potentiality most.The improvement of such oil well can be adopted the method for setting up dividing plate, setting-out awl and the water awl that disappears.
II class oil well: the initial aqueous rate is between 30%-80%, and moisture content rises to production time of 90% greater than 100 days, or the initial stage moisture content is less than 30% but moisture content rose to for 90% production time less than 150 days.Such oil well is generally the bottom water reservoir development well of penetrating out the part water layer, and dividing plate is heavily penetrated or set up to the improvement method after based on shutoff.
III class oil well: the initial aqueous rate be higher than 80% or the initial stage moisture content less than 80% but moisture content rose to for 90% time less than 100 days, such oil well penetrate out part mainly below oil-water interfaces, the improvement method is heavily penetrated after based on shutoff.
2. the evaluation of oil reservoir water flooding degree
Calculate the bottom water coning height according to the bottom water coning forecast model, the water cone height greater than or near effective pay thickiness, strong water logging, ultra-high water-containing; The water cone height is greater than not penetrating out effective pay thickiness, less than effective pay thickiness, and moderate water logging, the water heavy wool is few during actual production, and is high moisture; The water cone height is not less than penetrating out effective pay thickiness, and oil reservoir is water logging or weak water logging not.
3. oil reservoir remaining oil potentiality are analyzed
Do not consider the size of water to oil area, it is long-pending that the waterflood volume equals the water cone.Calculate the water logging volume of every mouthful of well till when decision-making according to the bottom water coning forecast model, the water logging volume of every mouthful of well is added up can obtain total water logging volume in oil field, and calculates total water logging percentage by volume kw, it has reacted the volumetric sweep efficiency of bottom water reservoir, can judge the size of remaining oil potentiality according to this value.Think kw≤ 0.2 o'clock, not water logging or weak water logging; 0.2＜kw＜0.5 o'clock, moderate water logging; kw〉=0.5 o'clock, strong water logging.
The variation trend of bottom water reservoir oil-water interfaces has the most directly reflected the propelling situation of oil field subterranean oil water termination and the quality of oil field development trend.The variation of oil-water interfaces comprises two parts, and one is the variation for the average oil water termination of whole block, and it has reacted the remaining oil potentiality of whole oil reservoir; Another then is the variation of individual well oil-water interfaces, and it has reacted the ability of taping the latent power of individual well.The reacting condition of oil-water interfaces the height of water flooding degree, it is more little that oil-water interfaces change, water flooding degree is low more, the remaining oil enrichment degree is big more.
4. the selection principle of end water tackling method
4.1 that sets up artificial dividing plate selects the well principle
The best approach that suppresses the water awl is to set up artificial dividing plate.But the effect that artificial dividing plate will be obtained must satisfy following condition:
(1) oil reservoir has clear and definite oil-water interfaces, and the oil reservoir water saturation is low;
(2) perforation exploitation position is more than oil-water interfaces;
(3) the oil reservoir inclination angle is less than 3 °;
(4) dividing plate should be set up at initial stage of development, and moisture content is greater than the DeGrain of 80% rear bulkhead;
(5) end water water body is more little, the low more effect of active degree is good more.
4.2 oil well setting-out awl method select the well principle
(1) natural setting-out awl method selects the well principle
(1) the fractured carbonate rock bottom water reservoir in low Water-cut Period, carry out many wells nature same period setting-out awl, can obviously improve the oil reservoir recoverable reserves, improved development effectiveness;
(2) the moisture lower effect of oil reservoir significantly shows that early pressure ratio presses evening;
(3) cut down output and press the awl amplitude to want suitably, rate of oil production needs control rationally, makes that the reservoir oil water termination is balanced to rise, thus can be greatly in the oil well amplitude at top, and the well of limit waist can be smaller, can obtain better effects;
(4), when improving recovery ratio, need suitably to reduce rate of oil production although cut down output and press awl effective in Water-cut Period of the middle end;
(5) belong to crack or high infiltration oil reservoir;
(6) underground viscosity of crude low (less than 10mPa.s).
(2) artificial setting-out awl method selects the well principle
(1) oil reservoir has clear and definite oil-water interfaces, and the oil reservoir water saturation is low;
(2) water ratio in oil well is less than 80%;
(3) it is better to be in the oil well effect of high-order bit;
(4) the oil well effect that reservoir buried depth is little, strata pressure is low is better;
(5) belong to crack or high infiltration oil reservoir;
(6) underground viscosity of crude low (less than 10mPa.s).
4.3 that adopts that water disappears the awl method selects the well principle
(1) moisture content is less than 60% oil well;
When (2) oil reservoir is positive rhythm, the oleophylic stratum, effective, anti-rhythm oil reservoir, wetability is hydrophilic, effective;
(3) vertical permeability is poor more with the more little effect of ratio of horizontal permeability;
(4) end water water body is more little, the low more effect of active degree is good more.
5. end water is administered the alternative condition of well
5.1 end water is administered the necessary condition that well is selected
(1) initial stage low moisture (moisture content is less than 40%);
(2) to high water-cut well, by time of low moisture rising paramount moisture (moisture content is more than or equal to 90%) greater than 150 days;
(3) oil reservoir penetrate Kai Ding circle to the distance of original oil-water level greater than 4m;
(4) original oil-water level is clear and definite.
5.2 end water is administered the adequate condition that well is selected
(1) penetrates Kai Dijie and be higher than original oil-water level;
(2) initial oil saturation is greater than 50%;
(3) vertical permeability is less than horizontal permeability;
(4) ratio of bottom water coning volume and oil reservoir volume is less than 0.3;
(5) well water is less than 80%;
(6) end water water body is more little, active degree is low more.
5.3 end water is administered the geology principle of selecting well
(1) because the oil well of bottom water cone and then water logging is positioned at the structure high-order bit;
(2) core intersection is big, rerum natura good;
(3) initial oil saturation is higher;
(4) the initial production ability is stronger;
(5) accumulative total extraction oil mass is less, the wellblock remaining oil enrichment.
6. definite principle of artificial baffle method partition position
(1) to new brought in well, partition position generally should be in the position of oil-water interfaces top 1m-2m.If partition position can be at the oil-water interfaces place or the position of oil-water interfaces bottom 1m-2m during less than 6m for core intersection.
(2) penetrate out layer when circle, bottom water cone top rises to, and water ratio in oil well is less than 80% o'clock, partition position should be in the position of oil-water interfaces upper water bevel radius less than 8m.
(3) rise to when penetrating out circle, layer top as end Shui Ding circle, partition position should be in the position of penetrating out below the 3m-5m of circle of layer top.
7. set up screening and the combination standard of dividing plate with sealing agent
7.1 blocking agent screening criteria
(1) be the globality blocking agent, promptly blocking agent is integrally curing or gelling;
(2) employed water shutoff agent is preferably the form of molecule or ion dispersion, and the reaction time is answered long enough;
(3) blocking agent should be combined, the blocking agent intensity height of should trying one's best;
(4) blocking agent used of nearly well must guarantee under big producing pressure differential not output;
(5) configuration of water shutoff agent and construction should be simple to operation, and construction is dangerous little;
(6) cost of blocking agent is low, the source is wide.
7.2 blocking agent combination principle
(1) when the distance between the circle, partition position and producing zone top during, should inject diverting agent (foam or reactive resin) simultaneously at producing zone when setting up dividing plate less than 0.8 times blocking radius.
(2) but set up the weak blocking agent of blocking agent well working strength far away of dividing plate, the nearly high blocking agent of well working strength.
8. plug agent amount computational methods when setting up dividing plate
Plug agent amount when setting up dividing plate can be calculated as follows:
q＝π(2r)2hφ
In the formula: total consumption of q-blocking agent, m3The r-blocking radius, m; φ-oil reservoir degree of porosity, decimal; H-baffle design thickness (getting 2m), m.
9. estimate the effect that end water is administered
9.1 set up the effect assessment of artificial dividing plate
Production curve (day production fluid, comprehensive water cut, day produce oil) by oil well and block carries out effect assessment.The reduction value of the increase of daily oil production and comprehensive water cut is big more, and effect is good more.
9.2 oil well is pressed the effect assessment of awl method
Water breakthrough well (moisture March under production) is pressed awl Evaluation on effect index: newly-increased water-free oil production period and the anhydrous oil production of volume increase; Contain well and press the awl effect assessment, be i.e. the increment of total cumulative recovery of oil well mainly with the sign that increases to of oil well oil recoverable.
9.3 adopt the disappear effect assessment of awl method of water
Water breakthrough well (moisture March under production) is pressed awl Evaluation on effect index: newly-increased water-free oil production period and the anhydrous oil production of volume increase; Contain well and press the awl effect assessment, be i.e. the increment of total cumulative recovery of oil well mainly with the sign that increases to of oil well oil recoverable.