摘要
报道了为大庆油田南二区试验区筛选井间示踪剂的结果。初选非分配性示踪剂为硫氰酸钾,分配性示踪剂为正戊醇、异戊醇（3-甲基丁醇）、正丁醇,在地层水（回注污水）中背景浓度均为零;与地层水配伍;3个浓度的3组示踪剂回注污水溶液在50℃放置10天后,各剂浓度保留率大于80%,其中正丁醇的浓度保留率大于90%;硫氰酸钾在回注污水中的溶液在50℃老化28天,浓度仅减小1%。正戊醇在油中的分配系数最大,异戊醇次之,正丁醇最小,均符合要求。50℃下醇在油砂上的吸附大于硫氰酸钾,正丁醇的吸附最大,使用NaOH为牺牲剂使硫氢酸钾和正丁醇的吸附率急剧下降至1.0%-0.1%。在4.4×4.4×78（cm））的人造岩心和φ2.5×50（cm）非均质储层岩心上进行的流动实验中,出现硫氰酸钾和正戊醇浓度峰的时间差分别为133、472 min,但醇浓度峰较平坦,出现硫氰酸钾和正丁醇浓度峰的时间差分别为1201、25 min,两峰均十分尖锐,由浓度峰时间差计算的岩心剩余油饱和度误差,分别为7.14%、7.12%和4.44%、4.48%。所选示踪剂为硫氰酸钾＋正丁醇,已投入现场应用。图4表6参6。
The results of experimentally screening interwell tracers for use in a trial area of southern district IT of Daqing are presented. The non-distributive candidate is potassium thiocyanate, KSCN, and the distributive-alcohols n- and iso-pentanol and n-butanol. They are all compatible with the formation water [recycled produced water （RPW）], in which their background concentration is zero. The 0.05,0.5, and 5.0 g/L RPW solution of 3 KSCN/alcohol sets after ageing at 50℃ in 10 days keeps 〉 80 % original viscosity for every chemical and 〉90%-for n-butanol; the KSCN solution in RPW losses only 1% viscosity after ageing at 50℃ in 28 days. The partition coefficient of the alcohols in oil phase, being satisfactory, is the largest for n-pentanol, intermediate fro iso-pentanol, and the smallest for n-butanol. The adsorption of the alcohols from mixed KSCN/alcohol solution on reservoir cores at 50℃ is larger than that of KSCN, being the largest for n-butanol and the adsorption rate of n-butanol and KSCN from mixed solution is decreased significantly to 1.0-0.1% by using NaOH as sasrificial agent. In core flow experiments on artificial homogeneos cores of 4.4 × 4.4 × 78 （cm） and heterogeneous reservoir cores of φ02.5 × 50（cm）, the time lag of n-pentanol to KSCN producing peaks is of 133 and 125 minutes, respectively, with the former peak being rather flat, and of n-butanol to KSCN producing peaks is of 120 and 125 minutes, respectively, with the former peak being distinct and sharp; in calculating residual oil saturation values in these cores from the time lag, errors of 7.14 % and 7.12 % are obtained in the case of KSCN ＋ n-pentanol and of 4.44 % and 4.48 %-in the case of KSCN ＋ n-butanol. KSCN ＋ n-butanol are selected and have been put into field used.
出处
《油田化学》
CAS
CSCD
北大核心
2007年第1期12-16,共5页
Oilfield Chemistry
基金
国家自然科学基金重点项目"低渗透油层提高驱油效率的机理研究"(项目编号50634020)部分研究成果
关键词
示踪剂
实验筛选
硫氰酸钾/醇组合
正丁醇
井间示踪剂测试
剩余油饱和度
大庆油田
tracers
experimental selection
potassium thiocyanate /alcohol combination
n-butyl alcohol
interwell tracer test
residual oil saturation
Daqing oil fields
