适宜高温高盐地层的无机涂层调剖剂室内研究

Profile modification agent with abio-gel coating for high-temperature and high-salinity reservoir

交联聚合物调剖在高温、高地层水矿化度条件下的应用受到限制。为了解决塔里木盆地高温、高矿化度地层水深层油藏的调剖问题,研究了WJSTP无机凝胶涂层调剖剂。该调剖剂与高矿化度地层水反应后形成密度与水相当的无机凝胶,以吸附涂层方式在岩石骨架表面逐渐结垢,形成无机凝胶涂层,使地层中的流动通道逐渐变窄而造成流动阻力,达到使地层流体转向、扩大波及体积的目的。采用瓶试实验和岩心物理模拟方法,研究了该调剖剂与油田水反应的凝胶化性能,以及无机凝胶涂层对多孔介质的封堵性能,并通过管流试验模拟涂层对大孔道的封堵效果。结果表明,WJSTP调剖剂与高矿化度地层水形成的无机凝胶具有极好的耐温、耐盐及热稳定性能,通过多次涂层,可实现多孔介质中不同程度的封堵,在管流模型中获得同样的无机凝胶涂层封堵效果。

Cross-polymer gel has limited application in profile controlling of high-temperature and high-salinity reservoirs. Reservoirs in Tarim Basin, NW China, were geologically developed in marine environment with high temperature and high salinity. To address the problem of deep profile modification in Tarim Basin, profile controlling agent with abio-gel coating (WJSTP) is developed by taking advantage of the multi-valence cations concentrated in both the formation and injection water and injects a compounded silicate to react with the cations to form abio-gel with the same density as water. Beaker test shows that the gel has desirable properties of heat resistance, salinity resistance and long-term stability. Core flood tests verify that, by slug injection, the process can gradually build long lasting residue resistance factor (RRF) for water flow in high permeability streaks, indicating a 'layering' or 'coating' mechanism.