Use of Real-time Monitoring to Minimize Chemical Incompatibility In Hydraulic Fracturing Fluid

Transcription

1 Use of Real-time Monitoring to Minimize Chemical Incompatibility In Hydraulic Fracturing Fluid Nancy Zakhour Callon Petroleum Company Jinxuan Hu Mark Patton Hydrozonix, LLC 1

2 Outline Problem Statement Gel Compatibility and the Realtime Monitoring Slickwater compatibility and the Realtime Monitoring 2

3 Problem Statement Slickwater Water-Based Fracturing Fluid Gel Fluid High Retained Conductivity Lower Requirement on Water Quality Less Chemical, Lower Cost Larger Water Volume Larger Horsepower Reduced Performance for Larger Proppant May Affect Conductivity Higher Water Quality Requirement More Chemicals, Higher Cost Lower Water Volume Smaller Horsepower Requirement Transport Large Proppants High pump pressure Gel failure Premature crosslinking 3

4 Cross-linked gel fluids Borate or Zirconium Crosslinker TSS, TDS, Chlorides, Hardness and Boron all affect gel compatibility. Once Gel recipe is developed water quality must remain in a narrow range to maintain gel compatibility Control of water quality is paramount 4

5 Gel Compatibility Testing Rheology Testing Viscosity Gel Stability Break Time 5

6 Crosslink Gel Compatibility Slide 1 of 2 Gel Test with Borate Crosslinker No Adjustments made Purely trying to identify compatibility issues Viscosity (cp) at 100/sec Viscosity vs. Time Instantaneous Borate Crosslink System 25ppt Guar 60/40 Fresh / Treated Produced Water 60/40 Fresh / Untreated Produced Water 100% Untreated Produced Water Temperature (F) Temperature (F) Time (min) 6

7 Crosslink Gel Compatibility Slide 2 of 2 Temperature effected stability 70/30 Blend showed significant improvement with temperature No changes in crosslinker concentration for 70/30 blend No ph adjustment for 70/30 blend No Buffers Viscosity (cp) at 100sec Viscosity vs. Time Delayed Borate Crosslinked Fluid at 250 o F and Water Samples 60/40 Untreated Water 60/40 Treated Water 60/40 Treated Water, Lower ph 60/40 Treated Water, Adjusted Caustic Concentration 60/40 Treated Water, Adjusted Crosslinker Concentration 70/30 Treated Water 70/30 Untreated Water Time (Minutes) 7

8 Real Time Water Quality Monitoring for Crosslinked Gel Frac Chloride / TDS Good Indicator of Quality Monitor Blend Consistency For KCl Equivalency Boron To Identify Inhibitor Dose Rate Bacteria Disinfection Monitoring Test Influent/Effluent Test Working Tanks Other Parameters ph / TSS / Hardness etc 8

9 Real Time Water Quality Monitoring Keep Water Quality Consistent Adjust Blend Rate Stage by Stage Fresh Water, bbl Produced Water, bbl % Produced 100% 80% Water volume, bbl % of Produced 60% 40% 20% 0 Pre* Fresh Water, bbl Produced Water, bbl % Produced 26.8% 25.7% 23.8% 27.0% 29.8% 30.2% 28.6% 27.7% 30.8% 30.8% 29.6% 27.1% 26.9% 28.8% 29.3% 26.7% 0% 9

10 Real Time Water Quality Monitoring Keep Water Quality Consistent Chloride, mg/l KCl Equivalent Produced Water Treated Water Pre % 6.0% 5.0% 4.0% 3.0% 2.0% 1.0% 0.0% KCl Equivalent of the Treated Water Stage Number 10

11 Real Time Water Quality Monitoring Keep Water Quality Consistent Boron in Produced Water, mg/l Produced Water Treated Water Boron in Treated Water, mg/l 0 Pre* Stage Number 0 11

12 Bacteria Monitoring How do we confirm disinfection Source Water Bacteria Testing Baseline Testing Influent/Effluent of Treatment System Bacteria Testing Continuous Testing Residual Disinfection / Working Tanks / Blenders Bacteria Testing Continuous Testing Proppant Testing Drillout and Flowback Monitoring Influent & Effluent Source Water Testing Working Tank / Blender Monitoring 12

13 What do we use for Bacteria Testing 13

14 Real-Time Bacteria Treatment Monitoring Untreated Treated % Reduction % 350 ATP, pg/ml Stage# Testing conducted on location, Real-Time confirmation Test the influent and effluent at different stages throughout the frac 80.0% 60.0% 40.0% 20.0% 0.0% % Reduction 14

15 Slickwater Non-ionic Three groups of FR Anionic Reduction of friction by 50% - 60% is possible May degraded by biocides or oxidants May affected by other coexisting chemicals Cationic 15

16 Effect of Ca 2+ on Anionic FR J. Bryant etc, Halliburton 16

17 Selection of Oxidative Biocides Oxidant Hydroxyl Radicals Oxidation Potential, V 20 O C 2.8 < 1 sec Ozone min. Disinfection Hydrogen Peroxide Chlorine Dioxide 1.8 Hours min. Chlorine min. Compatibility

18 Realtime Monitoring for Slickwater Frac Field Friction Loop Test Volumetric Detector Water sample Pressure reducing valve Shut off valve Flow control valve 7 kpa pressure sensor Test section 7 kpa pressure sensor

19 Friction Reducer Compatibility Friction Testing Baseline 2.50 Baseline 0.5 gpt 1 gpt 2.00 Pressure Differential,PSI Time, min

20 Friction Reducer Compatibility Friction Testing Chlorine Dioxide % Friction Reduction Baseline gpt FR ClO2 Treated Water ClO2 Treated Water gpt FR 40% 30% 20% 10% 0% -10% -20% -30% -40% Time, min

21 Friction Reducer Compatibility Friction Testing Ozone 60% Untreated+ 0.5 gpt FR Treated Treated gpt FR 50% % Friction Reduction 40% 30% 20% 10% 0% -10% Time, min

22 Disinfection vs. Compatibility Slickwater: HZO vs. Biocide vs. Chlorine Dioxide Friction Reducer Concentration, % in mass Hydrozonix Biocide ClO /10/ /12/7 2013/1/ /3/ /5/6 2013/6/ /8/ /10/3 2013/11/22 Fracturing Date Water Treatment Technology # of Wells FR Concentration, % in mass Biocide ClO Hydrozonix

23 Friction Reducer Compatibility Case 1: FR / SI Pressure Diff, PSI Untreated + FR Untreated + FR / SI Treated + FR Treated + FR / SI Time, min FR concentration was at 1.0 gpt, SI concentration was at 0.25 gpt. Both of the chemicals were obtained from ProPetro. Test was run at 1.5 L/min, room temperature. Clearly, there is the incompatibility of the FR with the SI. Ozone treatment reduced the friction factor of the water.

24 Friction Reducer Compatibility Case 2: Friction Testing for Two Different FRs Untreated FR1 Untreated FR2 Treated FR 1 Treated FR Time, min FR1 vs FR2. Both FRs were effective. First 20 minutes was baseline test. FR was No significant difference between added at time 20 min, following by the untreated and treated water. addition of breaker (XPA) at time 40 min. Rapid Increase of pressure after XPA addition Pressure Differentiate, PSI

25 Friction Reducer Compatibility Case 2: Friction Testing for Two Different FR Pressure Differentiate, PSI FR1-XPA FR2-XPA FR1-SI FR2-SI Time, min FR1 vs FR2. First 20 minutes was baseline test. FR was added at time 20 min, following by the addition of breaker (XPA) or SI at time 40 min. SI had little impact on the performance of either FR. FR1 might have been interfered by other frac chemicals.

26 Takeaways For Gel Fluid Maintain the water quality in a narrow range Gel compatibility test needs to be conducted to determine proper recipe Monitoring of blend rate, chloride, TDS and boron level is necessary Bacteria monitoring is important For Slickwater Different types of FR have different tolerances on water quality change Proper selection of disinfection technology Field friction loop testing to confirm compatibility 26

27 Thank You 27