Estimation of Oil Recovery and CO2 Storage Capacity in CO2 EOR Incorporating the Effect of Underlying Aquifers

Abstract

TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractAtmospheric concentrations of CO 2 have risen since the beginning of the industrial revolution, primarily as a consequence of fossil fuel combustion for energy production and other industrial activities. Recognizing the challenge imposed by the potential for climate change, recent initiatives by various governments and by energy producers target a significant reduction in the intensity of CO 2 emissions into the atmosphere. A major mitigation strategy for reducing the intensity and amount of CO 2 emissions into the atmosphere is CO 2 capture and sequestration, of which geological sequestration is a major component. Although enhanced oil recovery operations have the lowest capacity of all options for geological CO 2 sequestration, they are most likely to be implemented first because of the additional economic benefit that will help offset the cost of CO 2 sequestration.Assuming that the pore space previously occupied by the produced oil can be backfilled with CO 2 , a methodology has been developed for the identification and screening of oil reservoirs that are suitable for CO 2 flooding and for estimating their CO 2 sequestration capacity at depletion, as well as under enhanced oil recovery.

Economic evaluation on CO2-EOR of onshore oil fields in China

“…If good production data are unavailable, volumetric-based CO 2 storage resource may be preferred (Goodman et al, 2011). The methods suggested by Bachu et al (2004) were used to estimate CO 2 storage resource for a series of assumed slug sizes (hydrocarbon pore volume, HCPV) under a five-spot WAG strategy. This method predicted the fraction of oil produced, as well as the actual fraction of pore volumes of solvent or CO 2 injected at breakthrough and at any other fraction of HCPV.…”

Assessment of CO2 storage capacity in oil reservoirs associated with large lateral/underlying aquifers: Case studies from China

“…Reservoir simulation can be used for relatively precise capacity assessment if detailed reservoir data are available, while mass balance methods are mostly used to calculate the storage capacity for the preliminary site screening purpose (Shaw and Bachu, 2002;Shaw, 2003, 2005;Bachu et al, 2004Bachu et al, , 2007Goodfield and Woods, 2001;Hendriks et al, 2004). Generally, voided pore space caused by production process is mainly considered for CO 2 storage in oil reservoirs, while only structural or stratigraphical trap or small part of aquifer is used for the calculation of CO 2 storage capacity in saline aquifers.…”

CO2 mobility control and sweep efficiency improvement using starch gel or ethylenediamine in ultra-low permeability oil layers with different types of heterogeneity

“…The miscibility can decrease the interfacial tension by injecting supercritical CO 2 , which can dramatically enhance oil recovery. Field applications present miscible CO 2 flooding can enhance oil recovery by 8-15% (Winter and Jean, 2001;Espie, 2003;Pyo et al, 2003;Bachu and Shaw, 2004).…”