Treating Produced Water from Remote Natural Gas Operations with Zero Liquid Discharge at the Well Field and Compressor Stations Utilizing Adiabatic Concentration Principles - History of a Joint Development Project
Terry A. Beasy¹, Craig T. Clerkin¹, Jim Davis², and Bernard F. Duesel¹
¹Heartland Technology Partners, LLC, St. Louis MO, [email protected], [email protected], [email protected]
²Waste Management, Inc., Newtown, PA, [email protected]
Heartland Technology Partners, LLC (Heartland) and Seneca Resources Company (Seneca), Division of National Fuel Gas Company (NYSE: NFG) began a cooperative research and development program in February 2011 to evaluate performance of an adiabatic concentration process as applied to achieving zero liquid discharge (ZLD) when managing produced water from Marcellus Shale natural gas wells. Equipment installed at Pad F of Seneca’s Detwieler Well Field in Covington, PA was designed to confirm simple, reliable and effective means to continuously reduce produced water to stable solids that could be managed within conventional landfills that are permitted to accept well field waste streams. To meet these goals, solids produced in the concentration process would have to pass TCLP, Paint Filter and radiological testing protocol to be accepted for receipt at approved landfills.
Success would mean well head gas could serve as the sole source of electrical and thermal energy input to the concentration process, or waste heat from engines or turbines at compressor stations would be sole sources of thermal energy, which would be supplemented by electrical energy. In either case, major reductions in truck traffic for hauling produced water off-site for treatment and disposal would be achieved while water vapor could be discharged to atmosphere or be condensed for reuse in well field operations. Thus, concerns and liability for multi-media pollution associated with handling produced water on-site and within tank wagons would be mitigated.
The choice of Pad F as the R&D site had special meaning as produced water from horizontal shale bed wells in the area were recognized among the most difficult to manage compared to most all natural gas shale plays. This factor is punctuated by concentrations of barium and calcium as high as 8,000 and 18,000 ppm, respectively, and Total Dissolved Solids in the range of 128,000 to 195,000 ppm at the Detwieler gas field.
The presentation details positive results achieved in 2011 that include development of continuous in-line processes seamlessly integrated with a rugged and reliable adiabatic concentration process that: 1) sequester barium found within produced water to an insoluble, highly immobile form; 2) convert dewatered cakes of precipitated solids to solid mass that is transported in roll-off boxes to permitted landfills; 3) reduce truck traffic by 72+%; 4) emit clean stack gases that are saturated with distilled water vapor, which can be either discharged to atmosphere or recovered in conventional condensing systems; and 5) achieve ZLD as supernatant and filtrate liquid from solids/liquid separation equipment is returned directly to the concentration process.
AAPG Search and Discovery Article #90154©2012 AAPG Eastern Section Meeting, Cleveland, Ohio, 22-26 September 2012