Trinidad and Tobago (TT) is seeking to develop more economical methods of enhanced oil recovery to arrest the decline in crude oil production and to meet the current and future energy demand. The utilization of alkaline-polymer flooding to enhance oil recovery in TT requires key studies to be conducted to obtain critical information of the flooding system (soil type, additive type, pH, adsorption characteristics and rheological (flow) characteristics). Understanding the role of, interplay and optimizing of these variables will provide key input data for the required simulations to produce near realistic projections of the required EOR efficiencies. The parameters of various wells in TT were compared to the screening criteria for alkali-polymer flooding, and the EOR 4 well was found to be suitable and thus selected for evaluation. Laboratory adsorption studies showed that the 1000 ppm xanthan gum flooding solution containing 0.25% NaOH exhibited the lowest absorption capacity for the gravel packed sand and exhibited the lowest viscosity at all the tested shear rates. The lowest adsorption was 2.27 × 10⁻⁷ lbmole/ft³ which occurred with the 1000 ppm xanthan gum polymer containing 0.25% NaOH, and the evidence showed that the polymer was adsorbed on the other side of the faults, indicating that it has moved further and closer to the producing well. Implementation of an alkali polymer flooding resulted in an incremental increase in the recovery factors (~ 3%) compared to polymer flooding; however, a change in the oil recovery as a function of the alkaline concentration was not observed. The simulated economic analysis clearly shows that all the analysed EOR scenarios resulted in economically feasible outcomes of net present value (NPV), Internal Rate of Return (IRR) and payback period for oil price variations between $35 and $60 USD per barrel of oil. A comparison of the individual strategies shows that the alkali-polymer flood system utilizing 0.25% sodium hydroxide with 1000 ppm xanthan gum is the best option in terms of cumulative production, recovery factor, NPV, IRR and time to payback.

特立尼达和多巴哥（TT）正在寻求开发更经济的方法来提高石油采收率，以遏制原油产量的下降并满足当前和未来的能源需求。利用碱性聚合物驱油以提高TT中的油采收率，需要进行关键研究以获取驱油系统的关键信息（土壤类型，添加剂类型，pH，吸附特性和流变（流动）特性）。了解这些变量的作用，相互影响和优化将为所需的模拟提供关键的输入数据，以产生所需的EOR效率的接近实际的预测。将TT中各井的参数与碱聚合物驱的筛选标准进行了比较，发现EOR 4井是合适的，因此选择进行评估。实验室吸附研究表明，含有0.25％NaOH的1000 ppm黄原胶注浆溶液对砾石填充的砂表现出最低的吸收能力，并且在所有测试的剪切速率下表现出最低的粘度。最低吸附量为2.27×10^-7磅摩尔/英尺³这是由含有0.25％NaOH的1000 ppm黄原胶聚合物产生的，证据表明该聚合物被吸附在断层的另一侧，表明它已经向生产井移动得越来越近。与聚合物驱相比，碱性聚合物驱的实施导致采收率的增加（〜3％）。然而，未观察到油回收率随碱浓度的变化。模拟的经济分析清楚地表明，所有分析的EOR情景均导致在经济上可行的净现值（NPV），内部收益率（IRR）和投资回收期，油价在每桶35美元至60美元之间波动。对各个策略的比较表明，碱聚合物驱体系使用的是0。