The objectives of this project are to evaluate the feasibility of carbon dioxide (CO{sub 2}) sequestration in Texas low-rank coals and to determine the potential for enhanced coalbed methane (CBM) recovery as an added benefit of sequestration. The primary objectives for this reporting period were to construct a coal geological model for reservoir analysis and to continue modeling studies of CO{sub 2} sequestration performance in coalbed methane reservoirs under various operational conditions. Detailed correlation of coal zones is important for reservoir analysis and modeling. Therefore, we interpreted and created isopleth maps of coal occurrences, and correlated individual coal seams within the coal bearing subdivisions of the Wilcox Group--the Hooper, Simsboro and Calvert Bluff formations. Preliminary modeling studies were run to determine if gravity effects would affect the performance of CO{sub 2} sequestration in coalbed methane reservoirs. Results indicated that gravity could adversely affect sweep efficiency and, thus, volumes of CO{sub 2} sequestered and methane produced in thick, vertically continuous coals. Preliminary modeling studies were also run to determine the effect of injection gas composition on sequestration in low-rank coalbeds. Injected gas composition was varied from pure CO{sub 2} to pure N{sub 2}, and results show that increasing N{sub 2} content …

The objectives of this project are to evaluate the feasibility of carbon dioxide (CO{sub 2}) sequestration in Texas low-rank coals and to determine the potential for enhanced coalbed methane (CBM) recovery as an added benefit of sequestration. The main tasks for this reporting period were to correlate well logs and refine coal property maps, evaluate methane content and gas composition of Wilcox Group coals, and initiate discussions concerning collection of additional, essential data with Anadarko. To assess the volume of CO{sub 2} that may be sequestered and volume of methane that can be produced in the vicinity of the proposed Sam Seymour sequestration site, we used approximately 200 additional wells logs from Anadarko Petroleum Corp. to correlate and map coal properties of the 3 coal-bearing intervals of Wilcox group. Among the maps we are making are maps of the number of coal beds, number of coal beds greater than 5 ft thick, and cumulative coal thickness for each coal interval. This stratigraphic analysis validates the presence of abundant coal for CO{sub 2} sequestration in the Wilcox Group in the vicinity of Sam Seymour power plant. A typical wellbore in this region may penetrate 20 to 40 coal beds with cumulative …