低温低渗透砂岩油藏窜流大孔道深部封堵技术研究

Plugging Indepth Macroporous Flowage Channels in Low Permeability and Low Temperature Sandstone Reservoirs

所用堵剂为高强度的淀粉接枝聚丙烯酰胺交联凝胶SAMG-1,由<6%淀粉、4.5%-5.5%丙烯酰胺、0.003%-0.006%交联剂组成,35℃成胶时间受淀粉和交联剂用量控制,为18-20小时以上,成胶前黏度-100 mPa.s。该堵剂具有长期稳定性,在储层岩心中注入深度15 cm的堵剂,在35℃候凝48小时后及老化90天后,封堵强度分别为0.61和0.59 MPa/cm,封堵率分别为98.6%和98.1%。该堵剂优先进入高渗层,注入0.5 PV并成胶后,2组双填砂管组成的模型低、高渗管渗透率保留率分别为68.4%、0.7%和69.4%、0.0%。吉林扶余油田西一区+15-8.2区块有水井6口,油井13口,含水率达91.5%,注入水最快在5天内到达油井。报道了该区块整体深部调剖封堵窜流通道的情况,详细叙述了+15-9.2井施工中通过注入压力和井底回压控制注入流量,使堵剂陆续进入原生和次生孔道的工艺作业,该井设计注入堵剂92 m3。6口水井整体调剖后,油井产液量差别减小,产油量增加,有效期已超过了9个月,共增油843 t,含水平均下降3.87%。图7表1参8。

The plugging/sealing agent(P/SA) SAMG-1 is composed of <6% starch,4.5—5.5% acrylamide,and 0.003—0.006% crosslinker,has an initial viscosity ～100 mPa·s,gelates at 35℃ in 18—20 hrs or more controllably by adjusting the amount of starch and crosslinker used to form a strong gel.This P/SA possesses long term stability and the breakthrough pressure and the plugging rate for a reservoir core with the P/SA injected to 15 cm deep and gelated at 35℃ in 48 hrs are of 0.61 MPa/cm and 98.6% and after aging at 35℃ in...