GCS-YR油溶性降黏剂的研制与应用

Development and application of GCS-YR oil-soluble viscosity reducer

河南油田稠油属于特、超稠油,采用蒸汽吞吐辅助注降黏剂技术可实现经济有效开采,但在开采初期,地层中含水较少,水溶性降黏剂对油包水型乳状原油难以起到降黏效果,为此,研制了耐高温油溶性降黏剂。利用正交实验方法进行了GCSYR油溶性降黏剂的配方实验,确定了基本配方为:3%乙酸乙烯酯共聚物ZJ-3+2%脂肪胺聚氧乙烯聚氧丙烯醚ZJ-4+1%酯化改性聚醚ZJ-5+20%四氢萘ZZJ-6+74%溶剂油RJ-5,通过室内实验确定了最佳加药质量分数为3%。室内实验表明,该配方耐温350℃,对低含水原油降黏率可达80%以上,并且与油田用AR型集输破乳剂具有良好的配伍性。该降黏剂在井楼油田进行6井次现场试验,平均单井产量提高41 t,平均油气比提高0.03。GCS-YR型油溶性降黏剂适用于河南油田蒸汽吞吐后的稠油开采,可提高河南油田稠油油藏采收率。

Heavy oil produced in the Henan Oilfield can be classified as extremely or super heavy oil, which can be developed economically and efficiently by using viscosity reducer with assistance of steam huff-and-puff. In earlier stage of development, formation contains less water, and water-soluble viscosity reducer can hardly reduce viscosity of water-in-oil emulsion. Accordingly, a temperature-resistant oil-soluble viscosity reducer was developed. Orthogonal test was conducted to determine formula of the GCS-YR oil-soluble viscosity reducer, namely, 3% vinyl acetate copolymer ZJ-3＋2% fatty amine polyoxyethylene polyoxy propylene ether ZJ-4＋1% esterified modified polyether ZJ-5＋20% tetralin ZZJ-6＋74% solvent naphtha RJ-5. Through laboratory tests, optimal mass fraction of agent was determined to be 3%. Test results show that the formula system can endure temperatures up to 350 ℃ with capacities to reduce viscosity of low-water crude oil over 80%. In addition, the system displayed satisfactory compatibility with de-emulsifier of AR type for oil gathering and transmission in oilfields. Field tests of the viscosity reducer were performed in 6 wells in the Jinglou Oilfield with single-well productivity enhanced by 47 t and OGR enhanced by 0.03 on average. The GCS-YR oil-soluble viscosity reducer can be used for development of heavy oil after steam huff-and-puff to enhance recovery of heavy-oil reservoirs in the Henan Oilfield.