Enhanced oil recovery by CO₂injection in carbonate reservoirs

Abstract

The majority of carbonate reservoirs have low porosity and permeability in general because of having a high amount of matrixes that make a heterogeneous reservoir, however high permeable layers are fractured. This study shows the effect of carbon dioxide injection on the oil recovery factor using an ECLIPSE 300 compositional reservoir simulator for 3D modelling and the change of carbonate components reaction during CO 2 injection in experimental work. In addition, a high recovery factor has been recorded during miscible CO 2 injection compared to immiscible injection. Water alternative gas (WAG) has been used as an enhanced oil recovery (EOR) method to overcome an unfavourable mobility ratio of CO 2 flooding. Miscible CO 2 injection with the aid of WAG has also had a great impact on the dissolution of carbonate components in dissolving calcite and dolomite components. Consequently, CO 2 flooding has a relatively low recovery factor without any EOR techniques such as gravity stable displacement, WAG or mobility control. CO 2 injection below minimum miscibility pressure (MMP) reduces CO 2 emission, while it takes too long time to maintain reservoir pressure. On the other hand, CO 2 flooding above MMP improves pressure maintenance; causes oil swelling, and increases the oil density.

Perspectives of CO2 Injection Strategies for Enhanced Oil Recovery and Storage in Indian Oilfields

“…In such scenarios, the capillary pressure can significantly enhance gas saturation as a result of the non-wetting phase (gas) acting as the displacing fluid. 80 The ultimate gas saturation is significantly impacted by the pressure drop. As a result of the minor density differences between both the liquid and gas phases in the horizontal fluid flow instance, the influence of the pressure drop is not particularly noticeable, while the impact of the pressure drop in vertical cases is more complicated.…”

“…Because of the lack of natural CO 2 sources in India, they used anthropogenic CO 2 collected from thermal power plants for conceptualization. 80 It is essential for a CO 2 EOR project to match a large point source of carbon dioxide to its prospective sink in an aged oilfield. The Cambay Basin in western India is one of the oldest oil-producing basins in the country, and the region is also among the most urbanized in the country.…”

Study of the impact of injection parameters on the performance of miscible sour gas injection for enhanced oil recovery

“…The most common technique is the Claus reaction process where gases containing H 2 S are catalytically converted to elemental sulfur (Bennion et al 1999). Also, a viable alternative is the reinjection of the produced gas into the reservoir as an enhanced recovery technique or for storage (Abou-Sayed et al 2004;Bhatti et al 2019;Ceragioli and Gianelli 2008;Ghoodjani and Bolouri 2011;Hawez and Ahmed 2014;Nwidee et al 2016). However, concerns have been raised as to possible leakages to the surfaces through faults or unsealing traps.…”

“…This research work seeks to provide insight into the impact of injection parameters on the viability of miscible flooding of a light oil reservoir by the reinjection of sour gas (Abou-Sayed et al 2004;Benham et al 1960;Christiansen and Haines 1987;Eakin 1988;Elsharkawy et al 1992;Green and Willhite 1998;Haynes et al 2008;Holm and Josendal 1974;Khan et al 2013;Lake 1989;Orr and Silva 1987;Orr et al 1982). The reinjection of a rich waste acid gas stream directly into the producing light oil reservoir for the purpose of miscible flooding enhanced oil recovery using numerical simulation was studied putting into consideration the impact of certain injection parameters on the overall performance of the recovery process.…”

Efficiency of enhanced oil recovery by injection of low-salinity water in barium-containing carbonate reservoirs

“…More than 80% of carbonate reservoirs have oil-wet or mixed wettability characteristics (Hawez and Ahmed 2014;Dong et al 2017). Oil-wet systems typically have water breakthrough and high water production rates, which may result in high residual oil saturation.…”