Cryogenic CO2 capture in natural gas.

Abstract: Increasing world energy demand and pricing trends have encouraged oil and gas companies to look at developing contaminated natural gas fields previously deemed uneconomic. At the same time, world wide perceptions on climate change are pressuring energy companies to adopt global best practices to reduce carbon emissions. Developing currently unviable contaminated natural gas fields requires developing new technologies for high CO₂ gas treatment. Current technologies available in the market for natural gas treating may not be ideally suitable for treating highly contaminated natural gas where CO₂ geo-sequestration is required. Use of physical and chemical absorption solvents have been the most popular method for treating natural gas with high CO₂, and to a lesser extent, membranes and adsorption methods. These technologies remove CO₂ at near ambient pressures thus requiring substantial amount of compression to levels needed for geo-sequestration. Cryogenic CO₂ removal methods can capture CO₂ in a liquid form thus making it relatively easy to pump underground for storage or send for enhanced oil recovery. This new cryogenic CO₂ removal method has been researched and tested in a demonstration plant and is soon to be implemented in commercial field applications. This paper intends to share recent field experience and test results from Cool Energy’s CryoCell^® demonstration plant in Western Australia. The CryoCell^® process was developed by Cool Energy Ltd and tested in collaboration with other industrial partners including Shell Global Solutions. This presentation will also discuss and compare existing CO₂ treatment technologies for developing high CO₂ natural gas fields requiring CO₂ geo-sequestration with the CryoCell^® CO₂ capture process. Basic economic comparisons between the CryoCell^® process and an amine based process including CO₂ geo-sequestration will be presented. [Copyright &y& Elsevier]