Ayers, Walter B.¹, Jorge L. Garduño², Henri Morand², Duane A. McVay², Rahila I. Ramazanova², Jerry L. Jensen²
(1) Texas A&M University, College Station, TX
(2) Texas A&M University,

ABSTRACT: CO₂ Sequestration Potential Of Texas Low-Rank Coals

CO₂ from energy consumption is a primary greenhouse gas. In 2001, 274 electrical generation plants produced ~2.33x108 short tons (tons) or 55% of the total CO₂ emitted in the Texas. Nearly 1/3 of this CO₂ was emitted by the top 5 power plants. Thus, sequestering CO₂ from a few plants could significantly reduce emissions. Moreover, sequestration of CO₂ in coal beds may have the added benefit of enhanced coalbed methane (CBM) recovery.
To evaluate the feasibility and the environmental and economic impacts of CO2 sequestration in Texas low-rank coals, we assessed the (1) technical feasibility and volume of CO₂ that could be sequestered, (2) locations and quantity of CO₂ sources near coal injection sites, and (3) potential for enhanced CBM recovery.
Three CO₂ emission sources were identified near potential injection sites in low-rank coals less than 4,500 ft deep. Protected waters in major aquifers were mapped to establish the limits of potential injection projects. Based on CO₂ emissions, coal characteristics, and water quality, we selected Gibbons Creek, Sam K. Seymour, and Martin Lake power plants for sequestration evaluation. In 2001, these plants emitted 3.5x106, 12.2x106, and 18.4x106 tons of CO₂, respectively.
Computer simulation models of the 3 sites will be run to model injection of different mixes of CO₂, nitrogen and other gases. Thus, we will determine volumes of CO₂ that can be sequestered, the impact on CBM production, and potential water production volumes to be handled. This technology may be transferable to other low-rank coals in many parts of the USA.

AAPG Search and Discovery Article #90026©2004 AAPG Annual Meeting, Dallas, Texas, April 18-21, 2004