Application of material balance methods to CO ₂ storage capacity estimation within selected depleted gas reservoirs

Abstract

Depleted gas reservoirs are potential sites for CO 2 storage; therefore, it is important to evaluate their storage capacity. Historically, there have been difficulties in identifying the reservoir drive mechanism of gas reservoirs using traditional P / z plots, having direct impacts for the estimation of the original gas in place (OGIP) and dependent parameters for both theoretical and effective CO 2 storage capacity estimation. Cole plots have previously provided an alternative method of characterization, being derived from the gas material balance equation. We use production data to evaluate the reservoir drive mechanism in four depleted gas reservoirs (Hewett Lower Bunter, Hewett Upper Bunter, and North and South Morecambe) on the UK Continental Shelf. Cole plots suggest that the North Morecambe and Hewett Upper Bunter reservoirs experience moderate water drive. Accounting for cumulative water influx into these reservoirs, the OGIP decreases by up to 20% compared with estimates from P / z plots. The revised OGIP values increase recovery factors within these reservoirs; hence, geometrically based theoretical storage capacity estimates for the North Morecambe and Hewett Upper Bunter reservoirs increase by 4 and 30%, respectively. Material balance approaches yield more conservative estimates. Effective storage capacity estimates are between 64 and 86% of theoretical estimates within the depletion drive reservoirs, and are 53 – 79% within the water drive reservoirs. Supplementary material: A more detailed description of the aquifer modelling is available at https://doi.org/10.6084/m9.figshare.c.3803770.v1

国内減退油ガス田のCO₂貯留可能量評価とその開発の可能性について

“…Fig.3Comparison between the estimated CO 2 storage capacities of Japanese depleted gas fields obtained in this work and these of depleted gas fields found in the literature(Akai et al, 2021;Clarke et al, 2017;Shell, 2015; JAPEX, 2016) .Note that these values found in the literature were obtained using a numerical model calibrated with historical gas production data. The estimated CO 2 storage capacities by RITE (2006) included saline aquifer formations potentially existing below and/or above the hydrocarbon bearing formations and that connecting to the hydrocarbon bearing formations.…”

“…Note that RITE (2006) estimated the storage capacity of these fields including saline aquifer formations potentially existing below and/or above the hydrocarbon bearing formations and that connecting to the hydrocarbon bearing formations. 3 Comparison between the estimated CO 2 storage capacities of Japanese depleted gas fields obtained in this work and these of depleted gas fields found in the literature (Akai et al, 2021;Clarke et al, 2017;Shell, 2015;JAPEX, 2016) .…”

“…Gas (Shell, 2015) ，既往研究における英国 4 ガス田の評価 結果 (Clarke et al, 2017) ，既往研究における減退ガス田 Table 3 Result of CO 2 storage capacity evaluated for the 11 depleted oil fields in Japan. Because RITE (2006) reported the storage capacities of the following fields as the capacity of oil and gas fields, these are presented in Table 2 as the capacity of gas fields: 1) Higashi-Niigata, 2) Kubiki, and 3) Aga-Oki fields.…”

Archives of Mining Sciences

“…Moreover, the hO (havlena-Odeh [24][25][26]) diagnostic plots were implemented. They can be used to assess the energy conditions of a reservoir (cole plot) and verify the accuracy of the parameters describing an aquifer and the ogiP, which were obtained via optimisation [14,27].…”