Simple, Environmentally Friendly, and Economical
Methods to Maximize the Reuse of Produced Water
for Frac Operations
Barry Donaldson - TETRA Technologies
Agenda
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Challenges
Oilfield Water Cycle
Water Infrastructure & Treatment Planning
Controlled Water Blending
Case Study
Conclusion
Challenges
2000 to 2014 Production and Use Trends*
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Number of Well Stimulated Grew 49K to 600K
Stimulated Wells Accounted for 66% of Gas and 50% of Oil Production
90% of new US wells are hydraulically stimulated
Water volumes for horizontal wells increased from 177K gallons/well to
over 4M gallons/well
• Produced Water amounts to about $60M/day
*EIA and DOE Info
Water Management Cycle
Storage
Transfer
Truck
Treatment
Filtration
Stimulate
Produced
Source
Water
Disposal
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Water Management Cycle
Produced Water Reuse Benefits
• Reduced fresh water for operations
Storage
Transfer
Truck
• Reduced disposal of produced water
Treatment
Filtration
Stimulate
Produced
Source
Water
Disposal
• Reduced truck traffic for transport
and disposal, resulting in lower cost
and less HSE exposure
• Improved community relations due to
less impact on environment through
reduced dust, noise, and emissions
Lower Overall Cost
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Infrastructure Planning
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Estimated produced water volumes
over the life of the field
Estimated frac water volumes required
during the completion phase
Stimulation Fluid Types
Water quality types and treatment
required
Central gathering and storage facility
to support the operation
Water treatment strategy
Permian Infrastructure
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Fresh Water Storage
Produced Water Trunk Lines System
Produced Water Treatment and Gathering
Produced Water Storage and Blending
Frac Locations
Water Treatment Solutions
Treat Water for Frac Reuse
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Removal of residual hydrocarbon
Removal of suspended solids
Partial removal of soluble minerals
Bacteria Control
Blending Fresh/Saline/Waste can minimize treatment costs
Water Treatment Objectives
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Deliver a “clean” frac fluid down hole
– Bacteria, scale and corrosion free
Compatibility with other frac chemicals
Environmentally friendly
– Quick acting, Quick degrading
Real time monitoring and validation of performance
Make feed rate adjustments “on the fly”
Blending and transfer go hand-in-hand
– Any treatment depends on having a continuous
homogeneous water to treat
Cost effective and safe
Page 8
Blending Types
• Batch Process (Known Volumes to Storage)
Not Real Time
Results in the stratification of the fluid in the tank or pit
• Volumetric Mixing (Mix Known Volumes Turbulently)
Real Time
Water Variations Not Controlled
• Parameter Controlled (Controlled Input and Output)
Real Time
Input and Output Water Quality Measured
Volumes Adjusted Real Time
Blending Consistency
Batch and Volumetric Mixing
Parameter Controlled
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No Change for input Water Quality
Variable Output Quality
Adjusts for Water Quality
Consistent output
Blending Study
• Initial Parameters set at 25% produced water ratio
• Raised progressively to over 55% produced water blend
• Chlorides Output Proxy Maintained at 24,000 ppm throughout job
• Frac Fluid Performance remained consistent throughout first completion pad
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Results
• Doubled produced water usage to over 55%
• No impact on stimulation jobs
• Decreased fresh water used by 600,000 bbls
• Savings of $1.5M in water sourcing and disposal costs
• Savings of $15K-$20K per frac event by selling oil recovered from produced water
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Conclusions
• Conserves fresh water by blending reclaimed produced water sources with fresh water
• Provides an optimal fracturing fluid real time that meets water quality specifications
• Consistent fluid minimizes impact on frac, providing cost savings
• Compatible with all water treatment solutions
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Questions?
Barry Donaldson
VP Sales and Marketing
[email protected]
Appendix
Job Planning Questions
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What volume will be treated?
Number and size of tanks holding the water (and connections)?
What are the sources of this water?
Are all the tanks the same water source and specs?
What are in input specs of the water, current analysis of water ?
(TSS, pH, Cations – see specs below as examples)
What output specs are required?
– Solids
– Oil/Hydrocarbons
– pH
– Corrosion Control
– Bacteria
– Cations of Concern
What are treatment rates preferred/required?
Long Term Planning Questions
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What frac type will they be using? Slickwater, linear gel, crosslinked gel, hybrid?
How much completion work are they planning in the future?
– How many rigs?
– How many frac crews?
– Multi-pad wells? Wells per Pad?
– Average Frac volume per well? Average daily use of water per pad?
– Typical # of stages/ well? Wells per month?
How many days will the produced water sit in tankage or in a pit after treatment and prior to reuse?
What are the expected treatment rates (BPD) of flow-back and produced water?
Where will the treatment be added? What type is preferred? How will you measure success or failure? What
monitoring and performance criteria will be expected?
What water quality spec’s will be needed for each frac type? What are the maximum quantities of contaminants?
What contaminants do you think will pose the biggest issues?
Does the treatment need to be mobile? If so, how often does it need to be moved? Time between fracs?
Are there chemical analyses available for each of the water sources?
We will need to collect samples of the flowback, produced water and brackish water for complete water analysis
and lab pilot testing
What sources of water are you planning to use? In what ratio’s?
What is the expected bottom hole temperature and pressure?
What frac rate (bbl/min) expected?
What does the water management process and infrastructure look like? Block flow diagram? Water volumes?
Transfer methods? Storage type and volumes?