Optimization Approach to
Produced Water Management
Dan Tormey, Ph.D., P.G.
Cardno Ltd.
What is the Produced Water
“Problem”?
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Large volumes of water produced by oil and gas
Typically saline
May contain other contaminants
Volumes typically greater than can be
accommodated by injection
• Source of Public Concern
Waste or Resource?
United States
Australia
ALL produced water
considered a waste
Most states define
produced water as a
waste
Prohibition on surface
discharge unless
benefits to wildlife or
agriculture can be
demonstrated
Queensland
redefinition: Beneficial
if “no harm” can be
demonstrated
A New Source of Water
Treated produced water used for:
• Crop irrigation
• Stock watering
• Groundwater
recharge
• Wildlife habitat
support
• Crop irrigation
• Golf course
irrigation
• Stock watering
• Industrial uses
• Stream
discharge
• Encouraging
beneficial reuse
as a component
of the social
license to operate
Displaces demand on public potable water supplies
Produced waters
not created equal
Variable:
• Salinities
• Temperatures
• Other compounds
• Volume and change
over time
Beneficial uses
intensely site-specific
• Agriculture
• Industrial
• Ornamental plants
NO ONE
SOLUTION
How to Optimize for a
Site-Specific Solution?
FOUR STEPS
1. Understand the
source
2. Understand the
potential use
3. Understand the
available treatment
technologies
4. Have backup plans
Step 1: Understand the Source
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How much water produced over time?
What is the quality over time?
What is the temperature over time?
How much can be injected without
undermining resource recovery?
Step 2: Understand the
Beneficial Uses
Survey of local
opportunities
• Local water
users/needs?
• Ocean outfall?
• Stream
discharge?
• Geothermal?
Evaluate compatibilities
• Water quality
requirements
• Compatibility of
produced water
(treated or untreated)
with the use
Step 3: Understand Treatment Technologies
Untreated
• Compatibility and reliability
assessments
Injection
• Compatibility assessment
• Affect on other groundwater
resources
Variety of Treatment Options
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Ion exchange
Membranes (including RO)
Mechanical vapor recompression
Air stripping
Precipitation
Dilution
Characterize Source
Water
OPTIMIZATION
Identify Beneficial Uses and Water Quality
Requirements
Untreated
- Aquifer
Injection
- Industrial
Uses
- Limited Ag
Diluted/Moderately
Treated
- Limited
Agricultural
- Private Use
Fully Treated
- Unrestricted
Agricultural
Use
- Discharge to
surface waters
Pair Beneficial Uses with Treatment
- Reverse Osmosis
- Mechanical Vapor Recompression
- Dilution
- I/X; Organic Removal
- Other Options
Compare
Treatment
Technologies
and their
Cost
Effectiveness
• Balance cost and
reliability
• Create a menu of
uses that
– Support full time
operation
– Consider
potential loss of
some uses
• Understand
changes over
time
• Create backup
plans to enhance
system reliability
California Example
Optimization
Model indicated
that:
• Receiving
water and
upland studies
• Reverse
Osmosis
Treatment was
needed to sell
or discharge the
produced water
• Designed and
completed
entire approval
process
• Brine could be
reinjected to
producing
formation
• Coordinate
with equipment
vendors for
performance
standards
Australia Example
Optimization Model used to determine menu of
Beneficial Reuses
No Treatment:
Treated:
• Stock watering
• Industrial
washdown
• Dilution/discharge
– Irrigation
– Stream discharge
– Limited
opportunity for
injection
– Mechanical Vapor
Recompression
selected for
treatment
Ecuador/Columbia/Indonesia
• Large volumes of
produced water with
limited beneficial
reuse
• Growing concern over
Social License to
Operate
• Fact-Finding and
Benchmarking
• Optimization Model
applied over a national
territory
• Establish stakeholder
relationships
• Opportunity to learn from USA
and Australia experience
Summary
• A new view of produced
water: New resource, not a
waste
• Regulatory hurdles easing
as the beneficial uses are
demonstrated
• Regulatory uncertainty and
urgent need together create a
confusing marketplace
• Local solutions needed
• Optimization approach to
balancing source, end users,
and treatment technologies