Study And Application Of Cyclic Waterflooding In The Waterflood Development Of Sabei

Extra high water-cut stage of the development area of Sabei, strengthenedresearch and application of hydrodynamic method, achieved good results in practice.Cyclic water injection is through changing water injection timing and manner, createan unstable dynamic in the oil change, improving the develop ment effects of oilfields.Daqing Oilfield Sabei has entered into the extra high water-cut stage production, watercut rise slowed, but with progressive reduction of the recoverable reserves, oil goodeffects of conventional oil wells measures getting worse, potential effects is far betterthan the initial, and subject to technical and economic conditions, to further improvethe ground swept volume of water injection is very difficult. Therefore, in thissituation how to further control water rise increase in recoverable reserves, slowingproduction decline, indicating improving development effectiveness, improveingdevelopment effectiveness, improve economic efficiency a top priority, and the cyclicwater injection was proved at this stage is a very cost effective means.Sabei three layer series of development is central part of Daqing Placentia lineoil-bearing SI, higher oil, grape floral developmeng of large river, reservoir, part of theSaertu reserve with good vonnectivity, great thickness, as well as major reservoirs, allthe others were for non-mainliners, in order to develop this adjustment. Group belongmainly in these three sets of reservoirs in Northern songliaobasin depositional systems of large leaf-like Delta, part belongs to the flood plains of large rivers and rawmaterials deposits. Structure is relatively stable the region, lakes cover morespacious areas.Cyclic water injection mechanism is by changing the injection system, workinghours, in different vertically formed between the upper section attached to a pressuredifference, and generate sadditional chennling. The additional channeling can play arole in homogeneous reservoir vertical waterflooded, can improve developmentefficiency, and stability conditions between lower permeability and saturationvariances greater contradictions more prominent, cyclic water injection effect moreobvious. With penetration rate and saturated degrees differences of increases, layersegment between produced of additional pressure poor on more big, so in cycleinjection a cycle within by good layer to poor layer penetration flow of water on moremore, reverse flow of oil volume also on more more, reflect to indicators Shang iscontaining water of rose speed slowed even containing water declined, reduced loweffect invalid cycle, improved development effect.Plain transition zone and different development approaches make experimentnumericalsimulations, concluded that the most reasonable cycle time and way. Stopped layerkept wells way, especially stopped note good layer segment, keep even strengthenedpoor layer injection, actually good layer of high by cycle injection of effect, remainingoil get drive seeping, and poor reservoir is improved sucking water profile, originallynot sucking water of layer segment began sucking water, layer between contradictionsget ease, to this control has containing water of rose speed, reduced low effect invalidcycle. Pure oil province and there are province and there are some differences in thetransition zone, especially in the transition zone, especially in transition zone of fourbands, more development. Cyclic water injection in oil-pure embodiments ofmothods and in the transition zone of four different method on the corresponding layer.Experiment and numerical simulation analysis of reasonable water injection cycle, technical parameters injection cycle, technical parameters such as water pressurelimits, improving oil recovery in block, slowing water velocity.This papers eventually obtained conclusions, in oilfield in the low containingwater Republic cycle injection of stopped note time should control in3months within,in the high containing water period is should control in2months within in40daysaround for most suitable, and actual application in the found, for containing water highof transition with,, can appropriate will stopped layer kept wells this week note way ofimplementation half cycle plus long, its on produced oil of effects in60days aboveShi only gradually obviously, full wells stopped is control in50days within effect best.Using layers synchronized cyclic water injection method, oil remains water injection,avoiding the pressure flutuations, making oil field development situation has remainedstable, is the later stage of high water-cut effective ways to improve waterfloodingdevelopment effectiveness. Cyclic water injection mode and working system ofdetermining, in conjunction with the combination of block with the with thecombination of block geologica characteristics and development conditions, to takefully into account the vertical plane conflicts, combined with reservoir with reservoirdevelopment, injection-production relationship and interaction between the layers.Development of oilfields in the current conditions, should fully use existing layers andpatterns, through cyclic water injection pressure, improve the injection pressure,improve the utilization of water, crude oil stranded in State use. Reserve measures in apressure adjustment, increase the use of reservoirs in all aspects.