View
221
Download
2
Category
Tags:
Preview:
Citation preview
Optimization Approach to Produced Water Management
Dan Tormey, Ph.D., P.G.Cardno Ltd.
What is the Produced Water “Problem”?
• 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?
AustraliaMost states define
produced water as a waste
Queensland redefinition: Beneficial if “no harm” can be demonstrated
United StatesALL produced water
considered a waste
Prohibition on surface discharge unless benefits to wildlife or agriculture can be demonstrated
A New Source of Water
Treated produced water used for:
Australia:• Crop irrigation• Golf course
irrigation• Stock watering• Industrial uses• Stream
discharge
Ecuador, Columbia, Indonesia:
• Encouraging beneficial reuse as a component of the social license to operate
Displaces demand on public potable water supplies
USA:• Crop irrigation• Stock watering• Groundwater
recharge • Wildlife habitat
support
Variable:• Salinities• Temperatures• Other compounds• Volume and change
over time
Produced waters not created equal
Beneficial uses intensely site-specific• Agriculture• Industrial• Ornamental plants
NO ONE SOLUTION
How to Optimize for a Site-Specific Solution?
FOUR STEPS1. Understand the
source
2. Understand the potential use
3. Understand the available treatment technologies
4. Have backup plans
Step 1: Understand the Source
• 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• Ion exchange• Membranes (including RO)• Mechanical vapor recompression• Air stripping• Precipitation• Dilution
Characterize Source Water
Identify Beneficial Uses and Water Quality Requirements
Pair Beneficial Uses with Treatment - Reverse Osmosis
- Mechanical Vapor Recompression
- Dilution
- I/X; Organic Removal
- Other Options
Compare Treatment
Technologies and their Cost Effectiveness
Diluted/Moderately Treated- Limited Agricultural
- Private Use
Untreated- Aquifer Injection
- Industrial Uses
- Limited Ag
Fully Treated- Unrestricted Agricultural Use
- Discharge to surface waters
OPTIMIZATION• 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
• Receiving water and upland studies
• Designed and completed entire approval process
• Coordinate with equipment vendors for performance standards
Optimization Model indicated that:
• Reverse Osmosis Treatment was needed to sell or discharge the produced water
• Brine could be reinjected to producing formation
Australia Example
Optimization Model used to determine menu of Beneficial Reuses
No Treatment: • Stock watering• Industrial
washdown• Dilution/discharge
Treated: – 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
Recommended