复杂油气藏
複雜油氣藏
복잡유기장
COMPLEX HYDROCARBON RESERVOIRS
2013年
3期
67-70
,共4页
熊健%冯三强%马振昌%王绍平
熊健%馮三彊%馬振昌%王紹平
웅건%풍삼강%마진창%왕소평
酸压井%蚓孔区%启动压力梯度%应力敏感%有效应力%产能方程
痠壓井%蚓孔區%啟動壓力梯度%應力敏感%有效應力%產能方程
산압정%인공구%계동압력제도%응력민감%유효응력%산능방정
acid fracturing well%acid wormholing zone%start-up pressure gradient%stress sensitivity%effective stress%productivity equation
酸压过程中形成的蚓孔区将对酸压井产能产生影响。针对酸压后形成蚓孔区,根据压后流体渗流规律变化,建立了酸压井的物理渗流模型,推导建立了启动压力梯度和应力敏感共同影响下低渗油藏有限导流垂直酸压裂缝井产能预测模型,通过实例分析各因素对产能特征的影响。研究结果表明:油井产量随启动压力梯度增大而呈近似线性下降趋势;基于Terzaghi有效应力的应力敏感对油井产量的影响作用显著,油井产量下降幅度随压差增大而增大;油井产量随裂缝半长增加而增加,但增加幅度随之减小,而在一定裂缝长度下,裂缝导流能力存在一个最佳值;蚓孔区系统中的蚓孔长度和蚓孔区渗透率对油井产量的影响非常小,可忽略不计。
痠壓過程中形成的蚓孔區將對痠壓井產能產生影響。針對痠壓後形成蚓孔區,根據壓後流體滲流規律變化,建立瞭痠壓井的物理滲流模型,推導建立瞭啟動壓力梯度和應力敏感共同影響下低滲油藏有限導流垂直痠壓裂縫井產能預測模型,通過實例分析各因素對產能特徵的影響。研究結果錶明:油井產量隨啟動壓力梯度增大而呈近似線性下降趨勢;基于Terzaghi有效應力的應力敏感對油井產量的影響作用顯著,油井產量下降幅度隨壓差增大而增大;油井產量隨裂縫半長增加而增加,但增加幅度隨之減小,而在一定裂縫長度下,裂縫導流能力存在一箇最佳值;蚓孔區繫統中的蚓孔長度和蚓孔區滲透率對油井產量的影響非常小,可忽略不計。
산압과정중형성적인공구장대산압정산능산생영향。침대산압후형성인공구,근거압후류체삼류규률변화,건립료산압정적물리삼류모형,추도건립료계동압력제도화응력민감공동영향하저삼유장유한도류수직산압렬봉정산능예측모형,통과실례분석각인소대산능특정적영향。연구결과표명:유정산량수계동압력제도증대이정근사선성하강추세;기우Terzaghi유효응력적응력민감대유정산량적영향작용현저,유정산량하강폭도수압차증대이증대;유정산량수렬봉반장증가이증가,단증가폭도수지감소,이재일정렬봉장도하,렬봉도류능력존재일개최가치;인공구계통중적인공장도화인공구삼투솔대유정산량적영향비상소,가홀략불계。
The wormhole zone formed during acid fracturing can affect productivity of acid fracturing well.In view of the wormhole zone,based on change of fluid seepage law after fracturing,a physical seepage model for acid fracturing wells was established.And a productivity prediction model for vertical acid fracturing wells with finite conductivity in low-per-meability reservoirs was set up which is affected by start-up pressure gradient and stress sensitivity.From case analysis, it was studied on effect of various factors on productivity features.Results indicate that oil well productivity decreases with the increase of the start-up pressure gradient in a linear relationship;the stress sensitivity based on the Terzaghi’s effec-tive stress significantly affect the oil well productivity,and decreasing rang of the oil well productivity increases with the in-crease of the production differential pressure;the oil well productivity increases with crack length increase,increasing range of the oil well productivity after certain value decreases,and there is an optimum fracture conductivity under a certain crack length;wormhole length and permeability of acid wormhole zone have very little effect on the oil well productivity.