超稠油蒸汽驱先导试验效果分析

杜229块兴隆台油藏为中厚互层状超稠油油藏,单层厚度薄、储层物性好、原油黏度高,已进入蒸汽吞吐末期,综合含水率快速上升,产量递减严重,亟需实施开发方式转换。针对该区块蒸汽吞吐后期的特点,运用开发机理研究、数值模拟研究等方法,论证了超稠油蒸汽驱的可行性,并于2007年规划了7个70m井距"反九点"井组,开展蒸汽驱先导试验。经过8年的探索与实践,先导试验取得成功,井组年产油由转驱前的4.1×104t上升至5×104t左右,油汽比为0.17,采注比为1.09,采出程度达到53.8%,各项指标达到国际先进水平。通过对历史生产资料及监测资料分析研究,初步形成了超稠油蒸汽驱"先连通、再驱替"的驱油机理,掌握了影响生产效果的各项主要因素,总结了汽驱阶段的动态调控理念及方法。该试验的成功实施,突破了超稠油不能实施蒸汽驱的认识禁区。

Effect Analysis on the Pilot Test of Steam Flooding for Super Heavy Oil

Xinglongtai oil reservoir of block Du229 is a super heavy oil one with medium thickness interbed.Its single layer is thin and it owns a good physical property and high viscosity of crude oil.After years of development,it has stepped into the last phase of steam stimulation.It is ttrgent for this reservoir to transform development method to enhance the oil recovery since composite water cut is rising fast and the production is declining fast.Based on the research of development mechanism and numerical simulation,the feasibility of the steam flooding for the super heavy oil has been discussed according to the characteristics of the last phase of steam stimulation in this block.Since the pilot test was carried out in 2007,seven inverted nine-spot well groups with well space of 70 meters have been planned by now.After exploration and practice for eight years,this pilot test has achieved success.Yearly oil production of well group has risen from 41 thousand tons before to 50 thousand tons,the oil-steam rate is 0.17,the production-injection ratio is 1.09 and the degree After historical placement of recovery has reached to 53.8%.Each index has reached the international advanced level production data and monitoring data are analyzed through the steam flooding and researched ,the mechanism of oil disfor the super heavy oil has been formed：connecting first and then displacing.Main factors that influence the development effect are known.Dynamic control thinking and method during the steam flooding are summarized.The successful implementation of this experiment is the breakthrough of the steam flooding for the super heavy oil reservoir.