CO2 Utilization for Enhance Oil Recovery with Huff-N-Puff Process in Depleting Heterogeneous Reservoir

Currently, the reduction of carbon dioxide (CO2) emission has been increasingly concerned by many industries because CO2 is recognized as one of the main greenhouse gases. Some oil industries have applied commercial processes to enhance oil recovery and reduce greenhouse gas known as CO2 enhanced oil recovery (CO2-EOR). And one of the effective methods is the cyclic CO2 injection or CO2 Huff-n-Puff. This method is applied CO2 to extract additional oil from depleting reservoir by reducing oil viscosity and maintaining reservoir pressure. Accordingly, CO2 utilization is the key factor to success the CO2 Huff-n-Puff process in depleting oil reservoir. Consequently, it becomes the objective of this research which is to investigate the sensitivity of CO2 utilization and to evaluate the performance of CO2 Huff-n-Puff process in depleting heterogeneous reservoir by using numerical simulation. From the simulation, the results report that the highest sensitive parameter of CO2 utilization is CO2 injection rate, followed by CO2 injection time, and number of cycle. On the other hand, the lowest sensitivity is soaking time due to low pressure buildup rate in depleting reservoir. Moreover, higher CO2 utilization can be obtained by increasing of CO2 injection rate and time. Likewise, the increasing of CO2 Huff-n-Puff cycle can rise CO2 utilization due to the expansion of drainage area and reservoir pressure support. Finally, the carbon capture and storage technologies can help reduce CO2 utilization of Huff-n-Puff process by re-injecting of CO2 in subsequent cycles and storing of CO2 into depleted reservoir after crude oil is not economically produced. (C) 2017 The Authors.Published by Elsevier Ltd.