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在阐明裂缝性储层伤害评价方法基础上,对10 种处理剂作了伤害评价.从实验结果看,基本上可将处理剂分成二类,第一类处理剂(合成聚合物) 对裂缝性储层的伤害程度随裂缝宽度的增加而降低.其伤害机理为处理剂分子的吸附使得裂缝变窄,流动阻力增大,裂缝宽度越大,则因吸附作用产生的吸附膜所减小的流道在整个裂缝宽度中所占比例越小,表现出伤害越小.第二类处理剂( 腐植酸为主要原料)对裂缝性储层的伤害程度随裂缝宽度的增加而增加(在一定的裂缝宽度范围内).其伤害机理为:在裂缝空间内可能滞留有腐植酸与模拟地层流体( 水型为CACL2) 相互接触后,产生腐植酸钙沉淀.当裂缝宽度较小时,随着裂缝宽度的增加,产生的沉淀量越大,表现出伤害率增加;当裂缝宽度远远大于腐植酸钙沉淀颗粒时,伤害率会下降.本项工作为裂缝性储层优选钻井完井液体系提供了一定基础.“,”The evaluation of the damage by ten kinds of additives is made on the basis of expounding the evaluation method for fractured reservoir damage.According to the experimental results,the additives can be basically divided into two categories.The fractured reservoir damage degree by first category of the additives (synthetic polymer) reduces with the increase of fracture width.The damage mechanism is that the adsorption of additives, molecule makes fractures narrow and the flow resistance increase.The larger the fracture width,the smaller the ratio of the flow passage reduced by the adsorbed film formed as a result of adsorption effect in total fracture width,and the smaller the damage also.The fractured reservoir damage degree by second category of the additives (taking humic acid as main raw material) increases with the enlargement of fracture width(within the bounds of a certain fracture width).The damage mechanism is that the humic acid and the fluid in the simulated formation (CaCl 2 type)may be detained in the fractures,and when they contact with each other,the precipitation of calcium humate will occur.For small fracture width,the precipitation increases with the enlargement of fracture width and the damage rate raises;but for the fracture width which is far larger than the precipitated calcium humate particles,the damage rate reduces.This work provides a certain basis for optimizing drilling and completion fluid systems for fractured reservoirs.