Department of Civil and Environmental Engineering, School of Engineering and Digital Sciences, Nazarbayev University, Nur-Sultan 010000, Republic of Kazakhstan.
Department of Mechanical and Aerospace Engineering, School of Engineering and Digital Sciences, Nazarbayev University, Nur-Sultan 010000, Republic of Kazakhstan.
Environ Sci Technol. 2022 Jun 21;56(12):8571-8580. doi: 10.1021/acs.est.1c06834. Epub 2022 Jun 2.
CO-enhanced oil recovery (EOR) can have less GHG emissions compared to conventional oil production methods. The economy of CO-EOR can significantly benefit from the recent rise of carbon prices in carbon markets due to its greenhouse gas (GHG) emission savings. This study conducted a life cycle assessment (LCA) of CO-EOR in major hydrocarbon provinces of the world. Estimated net GHG emissions of CO-EOR were compared with GHG emissions of average produced oil in the given country. When sourcing CO from coal-fired power plants, Kazakhstan and China have net GHG emissions of CO-EOR of 276 and 380 kg CO eq/bbl, respectively, which are lower than the GHG emission factor of average oil produced in each of them. Significantly lower GHG emissions of CO-EOR are observed in other hydrocarbon provinces (Iraq, Saudi Arabia, Kuwait, etc.), where CO could be delivered from Natural Gas Combined Cycle (NGCC) power plants. However, the cost of CO capture is higher at NGCC power plants than at coal-fired power plants. Further, we developed a techno-economic assessment (TEA) model of the CO-EOR and integrated it with LCA to thoroughly consider carbon credits in its economy. The model was built based upon previous investigations and used statistics from a large industrial data set of CO-EOR to produce accurate estimates of the CO-EOR economy. The technical model iteratively estimated the balance of three fluids (crude oil, CO, and water) in the CO-EOR system with a 25 year operational lifespan and obtained actual data for the LCA and TEA models. The model was simulated for the Kazakhstan case with its oil market conditions for a demonstration purpose. TEA results showed that, with the available low-cost CO capture source or high CO cost in carbon trading, CO-EOR can compete with current upstream projects in Kazakhstan by simultaneously increasing oil production and reducing GHG emissions.
二氧化碳强化采油(EOR)的温室气体(GHG)排放量比传统采油方法要低。由于其温室气体减排量,二氧化碳强化采油的经济可以从碳市场中碳价格的近期上涨中获得显著收益。本研究对世界主要含油气省的二氧化碳强化采油进行了生命周期评估(LCA)。估计的二氧化碳强化采油净温室气体排放量与给定国家生产的平均石油的温室气体排放量进行了比较。当从燃煤电厂获取二氧化碳时,哈萨克斯坦和中国的二氧化碳强化采油净温室气体排放量分别为 276 和 380 千克二氧化碳当量/桶,低于两国各自生产的平均石油的温室气体排放因子。在其他含油气省(伊拉克、沙特阿拉伯、科威特等),二氧化碳可以从联合循环燃气轮机(NGCC)电厂供应,因此可以观察到二氧化碳强化采油的温室气体排放量显著降低。然而,与燃煤电厂相比,NGCC 电厂的二氧化碳捕集成本更高。此外,我们还开发了二氧化碳强化采油的技术经济评估(TEA)模型,并将其与 LCA 集成,以在其经济中全面考虑碳信用额。该模型是基于以前的研究建立的,并使用了二氧化碳强化采油的大型工业数据集的统计数据,以准确估计二氧化碳强化采油的经济情况。该技术模型对具有 25 年运营寿命的二氧化碳强化采油系统中的三种流体(原油、二氧化碳和水)的平衡进行了迭代估计,并为 LCA 和 TEA 模型提供了实际数据。为了演示目的,该模型针对哈萨克斯坦的情况及其石油市场条件进行了模拟。TEA 结果表明,在有低成本二氧化碳捕集源或碳交易中二氧化碳成本较高的情况下,二氧化碳强化采油可以通过增加石油产量和减少温室气体排放,与哈萨克斯坦目前的上游项目竞争。