Buenos Aires, 7 al 10 de agosto de 2012 Friction Reducers and the Challenge of High TDS Waters P. Watson, H. Kolla, A. Patel, R. Robinson, L. Jackson, and M. Nair

 Shale formations need to be hydraulically fractured before they can produce oil and gas  Fracturing requires pumping up to 150,000 m 3 water downhole at high velocity  Operators must consider water, energy, and environmental costs  Proper friction reducer selection can reduce costs US Energy Information Administration (accessed 5 July 2012).

Turbulent Flow Re > 4,000 Laminar Flow Re < 2,300 Flow Rate and Reynolds Number

Power Savings Virk, P. S. “Drag reduction fundamentals.” AIChE J. 1975, 21, 625–656. Pump at same flowrate using less power Pump faster with same amount of power

Paktinat, J.; O’Neil, B.; Tulissi, M. SPE , presented at the Canadian Unconventional Resources Conference, Calgary, November Find fresh water sources Transport fresh water Dispose flowback and produced water Reuse flowback and produced water Water Stress

Designing an Effective FR High molecular weight Linear structure Flexible backbone MW million Daltons Linear Aliphatic backbone Does not interfere with other additives Anionic Dissolves rapidlyInverse emulsion polymer Stable in solution Soluble in water with TDS > 236,000 ppm Tolerates high and low temperatures Stable from -35 to 50 °C

Inverse Emulsion Polymers Polymer A  Conventional anionic friction reducer  Resists freezing to -20 °C Polymer B  Anionic friction reducer for low to moderate brines  Resists freezing to -35 °C Polymer C  Anionic friction reducer for high brines  Resists freezing to -15 °C Polymer D  Anionic friction reducer for high brines  Resists freezing to -30 °C

33,541 ppm TDS Brine Compositions 104,975 ppm TDS

Laboratory-scale Friction Loop Volume: 20 L Test Section: 1.5 m of 12.7-mm diameter tubing Centrifugal Pump: 60 – 100 L/min Re 80,000 – 150,000 Triplex Pump: 30 – 120 L/min Re 40,000 – 160,000 Temperature: 2 – 80 °C

Friction Loop Data PsPs PpPp

Friction Reduction in Different TDS Waters

Time to Max FR in Different TDS Waters

Effect of Temperature on FR Performance in Surface Water

Effect of Temperature on FR Performance in Flowback Water

Summary  Hydraulic fracturing is needed for production of oil and gas from shale  Friction reducers allow operators to pump faster at the same power input, or pump at the same speed with a lower power input  Using high TDS water for frac fluid can save fresh water and reduce operating costs  Friction reducers have been developed that  Deliver 65 – 46% FR in water with TDS 33,541 – 236,840 ppm  Dissolve in 60 seconds or less  Perform across a variety of temperatures

Questions?