CARBON DIOXIDE SEQUESTRATION AND ENHANCED OIL RECOVERY CO-OPTIMIZATION
二氧化碳埋存与提高石油采收率协同优化
摘要：
世界范围内工业的蓬勃发展导致人类向大气中排放的 CO2 量不断增加，从而在全世界引起温室效应，引起大气升温，改变全球气候。另一方面，以提高采 收率(CO2-EOR)为目的将二氧化碳注入油藏已经商业化近 50 年。由于二氧化碳的购买成本问题，石油行业的生产作业以最大化油气采收率为目标，同时将 CO2注入量保持在最低水平。为了克服提采期间 CO2 封存的经济限制，有必要使用特定的工程方法同时最大化油气藏经济采收率和注入油藏的 CO2 量。这个过程被称为协同优化。为此，针对不同开发方案进行了多次模拟，以找到 CO2 最大封存量、可产出的最大石油量以及同时最大化这两个数值的最佳点及最佳开发方案。结果表明，使用反 5 点井网并实施水气交替注入(WAG)可以显著促进协同优化，而其他参数，如井网面积和注入速率需要根据具体情况进行评估，同时要考虑经济因素。
关键词: 气候变化，二氧化碳，储存，封存，提高采收率，协同优化
Abstract: The worldwide growth of industry leads to continuous rise of anthropogenic emission amount into the atmosphere, which causes greenhouse effect all over the world, that is heating up the atmosphere and changing the global climate. On the other hand, carbon dioxide injection into oil reservoirs for the purpose of enhancement of oil recovery (CO2-EOR) has been commercially used for nearly 50 years. The operations in petroleum sector are being carried out in a way to maximize the recovered oil while keeping the amount of CO2 injected at its minimum due to the purchase cost of carbon dioxide. To overcome the economic restrictions for CO2 sequestration during EOR, it is necessary to simultaneously maximize economic oil recovery and the volumes of CO2 injected in oil reservoirs using an engineering approach. This process is named as co-optimization. For this purpose, several simulations for different scenarios are being carried out to find the maximum amount of CO2 that can be stored, maximum amount of oil that can be produced, and an optimal point for simultaneous maximization of both numbers.
Results show, that using inverted 5 spot pattern and implementing water-alternating gas (WAG) injection can significantly contribute to the co-optimization, while other parameters, such as pattern area and injection rate need to be evaluated on case by case basis, considering economical factors as well.
Keywords: Climate Change, CO2, Storage, Sequestration, Enhanced Oil Recovery, Co-Optimization
