辽河油田杜124井区双北29-37井组MD膜驱矿场试验

Field Pilot on Molecular Deposition Filming/Floodingat Well Group SB-29-37 of Block Dujiatai-124 in Liaohe

辽河油田杜家台124井区油藏埋深～3000m,地层温度110℃,平均渗透率0.029μm3,原油50℃粘度31mPa·s,凝点28.5℃,井区采出程度仅6.17%。该井区双北29 37井组包括1口注水井和3口采油井,驱油试验前注水困难,日注水量降至60m3,注水压力升至19.8MPa,井组日产油7.6t(单井0.9～4.3t),含水82.0%(单井73.0%～85.5%)。根据设计试验方案,从2001 09 30开始,每天从注水井注入有效浓度25%的MD 1工业膜驱剂100kg,15天共注入1.5t,截止2001 12 27,井组累计增产原油157t,注入1t化学剂增产原油105t,驱油试验在经济上是成功的。产油、含水、产液曲线表明,膜驱剂注入开始后10天左右,井组日产油量明显上升,最高达12.4t(37.3t/3d),15天左右井组含水明显下降,最低达73%;注入膜驱剂后井组日产液量增加,最高达53.4t(160.3t/3d),较试验前平均值增加30%。认为油井产液量增加是低渗透油藏MD膜驱见效的现场判据。图5表1参6。

The reservoirs of block Dujiatai-124 in Liaohe are characterized by depth ～3 000 m, temperature 110℃, average permeability 0.029 μm^2, crude viscosity 31 mPa·s(50℃), crude pour point 28.5℃ and very low oil recovery of 6.17%. The well group SB-29-37 of the block consists of 1 water injection and 3 oil production wells and before the field pilot starting its production status was as follows: daily water injection decreased to 60 m^3, injection pressure increased to 19.8 MPa,daily oil production 7.6 t for well group and 0.9—4.3 t for individual wells, water cut 82.0% for well group and 73.0%—85.5% for individual wells. According to a properly designed pilot trial project, 25%-concentated commercial MDFF agent MD-1, an organic diammonium salt, was introduced into the water injection well in amount of 100 kg daily and 1.5 t totally in 15 days starting from Sept 30, 2001 and additional oil production of 157 t was observed for whole well group on Dec 27, 2001, that is, 105 t of additional oil produced per 1 t of the chemical injected. The field pilot trial is successful economically. The curves of liquid and oil productivity and of water cut showed that for whole well group the oil productivity notably raised in 10 days after MD-1 injection beginning and reached a peak value of 12.4 t/d (37.3 t/3 d), the water cut significantly lowered in 15 days and reached a minimum value of 73% and the liquid productivity raised after MD-1 injection finished and reached a peak value of 53.4 t/d(160.3 t/3 d), a value by 30% higher than average value before the pilot trial. It is ascertained that increase in liquid productivily should be considered as the response of low permeable reservoirs to molecular deposition filming/flooding.