喇嘛甸油田水驱注采调整技术指标的再确定

REDETERMINATION OF THE TECHNICAL INDEXES OF THE INJECTION-PRODUCTION ADJUSTMENTS OF WATERFLOODED LAMADIAN OILFIELD

喇嘛甸油田进入特高含水期,无效循环加剧,剩余油更加零散,开发调整难度进一步加大。为满足水驱开发调整需求,结合油田开发实际,对油田特高含水后期原有水驱注采调整标准进行完善研究。利用渗透率级差、变异系数与吸水砂岩厚度比例关系,建立层内和层间细分注水调整新界限。实施后,单层砂岩厚度由3.9 m调整到3.0 m,渗透率级差由4.5调整到4.1,变异系数由0.57调整到0.53,细分后砂岩吸水厚度比例达到86.6%;层间渗透率级差由3.8调整到3.3,变异系数由0.49调整到0.42,细分后砂岩吸水厚度比例达到85.7%。利用数值模拟方法,分析采收率、产出投入比与注采强度(产液强度)之间的关系,确定合理的注水强度(产液强度)界限,完善平面调整标准。精细调整后,累计控制无效注水167.46×10~4m^3,控制无效产液252.74×10~4t,增加有效注水88.61×10~4m^3,增加有效产液171.96×10~4t。

After entering into the extra-high watercut stage for Lamadian Oilfield,the ineffective cycle has become serious,the remained oil has been rather scattered,the difficulty of the development adjustment has been more serious. In order to meet the waterflooding adjusting requirements,integrating with the oilfield development reality,the improved researches were conducted on the original waterflooding injection-production adjusting criteria at the later stage of the extra high watercut of the oilfield. With the help of the relationships between the permeability differential,variation parameter and water absorbed thickness ratio,the new limits are established for the intraformational and interbedded fine classified water-injecting adjustments. After the stimulations,for the individual layer,the sandstone thickness was adjusted from 3. 9 m to 3. 0 m,the differential was reduced from 4. 5 to 4. 1,the variation parameter was decreased from 0. 57 to 0. 53,the finely classified water-absorbed thickness ratio reached 86.6%; for the interbeds,the differential was reduced from 3. 8 to 3. 3,the variation parameter was decreased from0. 49 to 0. 42,the ratio reached 85. 7%. By means of the numerical simulating method and analyses of the relationships between the recovery factor,input-output ratio and injection-production and liquid production intensities,the reasonable intensity limits were determined,so the planar adjusting standards were improved. Since the fine adjustments,the accumulative controlled ineffective water cycle has reached to 167. 46 × 10~4m^3,the dominated invalid liquid has been up to 252. 74 × 10~4 t,the effective injected water has enhanced to 88. 61 × 10~4m^3. the increased valid liquid production has reached to 171. 96 × 10~4 t.