Integrated Electrodialysis Process for Coalbed Methane Produced Water Treatment

Moon, Paula¹, Seth Snyder¹, Thomas Hayes² (1) Argonne National Laboratory, Argonne, IL (2) Gas Technology Institute, Des Plaines,

The Colorado Energy Research Institute (CERI) at the Colorado School of Mines, has brought together a team of scientists and engineers to address many aspects of produced water management from production through treatment and /beneficial use. In support of this project, a collaborative effort between Argonne National Laboratory and the Gas Technology Institute is using an integrated electrodialysis (ED) process for water treatment. The anticipated benefits are enhanced coalbed methane (CBM) produced water quality, extended life of injection wells by 10-fold, reduce treatment cost to 10-15 cents per barrel and use of 90% of the water for beneficial use. If treatment system effluent is to be made available for beneficial use (such as irrigation, livestock operations, groundwater recharge, etc.), the water stream must comply with certain water quality criteria; some of these guidelines are defined by State regulations. Beneficial use criteria that are applicable to CBM produced water mainly focus on three parameters: total dissolved solids (TDS), sodium absorption ratio (SAR) and pH.

The effort to develop ED processing for the conditioning of produced water for beneficial use is currently employing laboratory scale ED prototype equipment. Experimental results with actual CBM produced water using selective and non-selective electrodialysis membranes, long term membrane performance, membrane fouling and power requirements will be discussed. Technical results will highlight degree of desalination of the desalted water as it relates to SAR, pH and TDS values suitable for beneficial use target (livestock drinking and water irrigation in the Power River Basin) as well as an estimate of the upper salt concentration in the rejected stream. Overall performance and economic projections for ED will be compared to available information on RO and will be presented in this poster presentation.

AAPG Search and Discovery Article #90055©2006 AAPG Rocky Mountain Section Meeting, Billings, Montana