Reservoir Modeling and Simulation of the Devonian Gas Shale of Eastern Kentucky for Enhanced Gas Recovery and CO2 Storage

Abstract

Shale gas and other unconventional gas plays have become an important factor in the United States energy market and are often referred to as statistical plays due to their high heterogeneity. They present real engineering challenges for characterization and exploitation, and their productivity depends upon an inter-related set of reservoir, completion and production characteristics.The Devonian Ohio shale of eastern Kentucky is the State's most prolific gas producer. The gas shale underlies approximately two-thirds of the state, cropping out around the Bluegrass Region of central Kentucky and having a sub crop beneath the Mississippi Embayment in western Kentucky. This paper describes the reservoir modeling and history matching of a Devonian Gas Shale Play, eastern Kentucky, its potential for CO 2 enhanced gas recovery and storage.A geologic model of the shale has been compiled from mineralogical, petrographic, core, production, and wireline data. The COMET3 multi-phase, dual porosity simulator is being used to investigate CO 2 injection into the shale for enhanced gas recovery. To accomplish this, a subset of wells surrounding the potential injection site has been selected for further study. These eight wells cover approximately 5,300 acres of productive shale. The reservoir was subdivided into the Upper Ohio and Lower Huron members. To capture geological heterogeneity, gas production rates for these wells served as a proxy to characterize fracture permeability using geostatistical methods. Well production was history matched applying an automated process. Finally, several CO 2 injection scenarios spanning huff-n-puff to continuous injection were reviewed to evaluate the enhanced gas recovery potential and assess the CO 2 storage capacity of these shale reservoirs.

Worldwide Status of CCUS Technologies and Their Development and Challenges in China

“…Encouraged by the successful application of CO 2 in oil and gas recovery, its application in aiding the production of shale gas began in recent years [76][77][78][79][80][81]. There has also been progress in replacing water by supercritical CO 2 as the injection fluid in the fracturing technology [82][83][84][85][86].…”

Mechanisms for CO2 Sequestration in Geological Formations and Enhanced Gas Recovery

“…Recently some studies have illustrated that CO2 injection can be considered as a method of EGR [93][94][95][96].…”

“…The injection of CO 2 may increase the rate and the volume of natural gas recovered from a reservoir [95,97] as CO 2 can be trapped in shale gas through sorption onto organic materials and clay minerals as a sorbed gas with the parallel displacement of natural gas. Nuttall et al [95] showed that continuous CO2 injection (300 tons) over a period of 45 days can lead to significant improvement in recovery.…”

“…Nuttall et al [95] showed that continuous CO2 injection (300 tons) over a period of 45 days can lead to significant improvement in recovery. As previously discussed, shale gas formations include organic materials.…”

Data-driven proxy at hydraulic fracture cluster level: A technique for efficient CO2- enhanced gas recovery and storage assessment in shale reservoir

“…Organic black shale reservoirs may behave similarly to coalbed methane by having high affinity to adsorb CO 2 and displace methane at a ratio of two to one, or more. If this is the case, organic shales may serve as an excellent sink for CO 2 and have the added benefit of serving to enhance natural gas production (Nuttal et al, 2005;Schepers et al, 2009).…”