Abstract: A successful water shut-off pilot test was carried out at a deep production well with high temperature and bottom water in the Carboniferous reservoir of Shixi Oilfield.After the water shut-off treatment had been made in the reservoir for 189 days,the cumulate liquid production decreased by about 3159 tons,and the cumulate oil increment reached about 570 tons.The liquid production per day gradually reduced from 105 tons to 78 tons after treatment for three months.A new method of three-section plugging was used to deal with the harsh reservoir conditions.The temporary plugging agent,main slug (surfited larch tannin extract) and sealing cement were injected into the reservoir separately.The injected temporary plugging agent could seal the zones for about 15 hours,and then the main slug of water shut-off agent gets into the water zones selectively.The formed gel of plugging agent with the surfited larch tannin extract may resist high temperature at bottom hole and have a good thermal stability.The slug of sealing cement could enhance the strength of the water shut-off agent.

Key words: water shut-off, gel, permeability, surfited larch tannin extract, pilot test, enhanced oil recovery

摘要： 通过室内研究和现场先导性试验,石西油田石炭系深井高温底水封堵首次取得了突破性进展.在堵水处理后189d内,产液量累计减少319t,原油累计增加70t.封堵前的日产液量为10t,处理3个月后逐渐降至78t,并维持了较长时间.针对石炭系深井底水高温的油藏条件,采用暂堵剂-改性栲胶凝胶-水泥封口三段塞技术提高了封堵的成功率.即:先用暂堵剂暂堵油层约1h,使后续注入的主剂段塞选择性地进入水层;形成的改性栲胶凝胶封堵层耐高温、热稳定性好;其后用水泥封口段塞提高封堵层强度.

关键词: 堵水, 凝胶, 渗透率, 改性栲胶, 先导性试验, 提高采收率