Calculate that 1,300 to 1,500 L of water could be extracted and managed for every metric ton ... managed per year ... Source: CETCO Oilfield Service Company ...
Management of Water Extracted From Carbon Sequestration Projects: Parallels to Produced Water Management John A. Veil, Christopher B. Harto Argonne National Laboratory and Andrea T. McNemar DOE - National Energy Technology Laboratory SPE Americas E&P Health, Safety, Security and Environmental Conference Houston, TX
March 21-23, 2011
Acknowledgments
DOE/NETL provided funding to support the work Coauthors
Outline of Presentation
Why is water extracted? Water extraction issues Options for managing extracted water Economics Challenges
Why Is Water Extracted?
CCS projects are likely to inject huge volumes of CO2 into underground formations with suitable properties Injection of large volumes of material will create a plume and associated pressure front – In large-scale projects, the plume could extend laterally for several kilometers – This creates more opportunity for the plume to intersect conduits to aquifers and/or the surface
The size of the plume can be reduced by extracting the water already present in the injection formation – Presume that the formations will be deep saline formations
Key Water Extraction Issues When – Before, when injection begins, delay then begin
Frequency – Continuous, intermittent
Quantity Where – Near well bore, offset – Single well, multiple wells • Plume steering
– Vertical well, horizontal well
What to do with the water – Focus of our study
Scope of Project
Identify formations proposed by regional partnerships as suitable deep saline formations for receiving CO2 Examine water quality in those formations Identify and evaluate management options for extracted water – – – – –
Minimize water managed at the surface Reuse opportunities Disposal options Treatment technologies prior to reuse or disposal Opportunities for deriving secondary value
Evaluate costs and challenges
Target Formations Visited the websites of each regional partnership to identify key target formations – Found 99 formations or basins identified as potential future sites for carbon sequestration – The total estimated capacity of these saline formations is 1.7 to 20 trillion metric tons
Obtained a large database of historical produced water data from NATCARB – Found geochemical water quality information for 61of the 99 locations
Deep Saline Water Quality Examples of the geochemical data – Formation TDS varies significantly by location – Formation pH ranges from slightly acidic to slightly basic
Management solution must be targeted to unique local brine chemistry
Variation in TDS Between Regions
9
Other Constituents (1)
10
Other Constituents (2)
11
How Much Water Could Be Involved? • Assume a CO2 density of 0.65 to 0.78 g/cm • Calculate that 1,300 to 1,500 L of water could be extracted and managed for every metric ton of CO2 injected • This equals a range of 8.1 to 9.5 bbl of water/metric ton of CO2 and an average of 8.8 bbl/metric ton • U.S. produced water generation volume was 21 billion bbl/year in 2007 • The U.S. emitted 5.9 billion metric tons of CO2 in 2008 • Assuming at some point in the future carbon sequestration is scaled up to be equivalent to 10% of 2008 emissions, and an equivalent volume of water is extracted to the volume of CO2 sequestered, this would require that about 5 billion barrels of water would need to be extracted and managed per year • This is about one-fourth of the water volume currently managed by the oil and gas industry.
Extracted Water Management Options • Follow 3-tier water management/pollution prevention hierarchy – Water minimization – Recycle/reuse – Treatment and disposal
• Use most environmentally friendly option where possible
Minimize Water Managed at the Surface
Inter-formation transfer
Need to ensure that water chemistry is compatible between formations
Reuse of Extracted Water Use as is – Injection for recovering more oil – Injection for hydrological purposes
Use after treatment – Industrial – Agricultural – Drinking
Injection for Recovering More Oil – California • Nearly 25,000 produced water injection wells • 1.8 billion bbl/year total injection – 900 million bbl/year water flood – 560 million bbl/year steam flood – 360 million bbl/year injection for disposal
– Texas • 38,540 wells permitted for enhanced recovery – 5.3 billion bbl/year • 11,988 wells permitted for disposal – 1.2 billion bbl/year
Injection for Hydrological Purposes Subsidence control
Industrial Use Cooling water makeup Use in drilling fluids or hydraulic fracturing fluids Dust control Other
Agricultural Use Irrigation Livestock and wildlife watering Managed wetlands Source: USDA
Source: USFWS
Source: USFWS
Options for Disposal of Extracted Water Discharge – Probably only practical when located near the ocean
Injection to non-hydrocarbon producing formation – Injection of salt water is likely to face less stringent requirements than injection of CO2 – Would need clarification of UIC regulations • Would not automatically qualify for Class II injection well status
Evaporation Offsite commercial disposal
Evaporation Evaporation ponds Mechanical evaporation Freeze-thaw evaporation Source: BC Technologies Ltd.
Source: U.S. Fish and Wildlife Service Source: BC Technologies Ltd.
Offsite Commercial Disposal
http://www.ead.anl.gov/project/dsp_topicdetail.cfm?topicid=18
Treatment Technologies for TDS/Salt Removal
Membrane processes Ion exchange Thermal distillation Others
Membrane Processes
Filtration Reverse osmosis
Ion Exchange
Overflow H2O
D
Loop Valves (Typical) D
Backwash
A
A Pulse Water
Feed Water
Pulse
B
B Adsorption
Displaced Water
Treated Water Spent Brine
C
C Clean Water
Rinse Acid Regen
Regeneration
Ion Exchange Service
Source: Severn Trent Services
Resin Pulsing
Thermal Distillation
Source: Altela Inc.
Source: Altela Inc.
Treatment Technologies for Organics Removal
Physical separation Flotation Adsorption Others
Physical Separation
Separation Hydrocyclone Filtration Centrifuge
Source: Natco Source: USEPA
Flotation
Source: Natco
Adsorption
Organoclay Activated carbon Zeolite
Source: CETCO Oilfield Service Company
Opportunities for Secondary Uses
If hot enough, can generate geothermal energy – RMOTC trial – Borealis Geopower project in Canada
Mineral extraction – Li – others
Produced Water Management Information System Shows More Information on These Technologies
http://www.netl.doe.gov/technologies/PWMIS/
Cost Considerations The cost of managing large volumes of extracted water can be a significant factor in the economic viability of a CCS project The total life-cycle cost includes: – The cost of constructing treatment and disposal facilities, including equipment acquisitions – The cost of operating those facilities, including chemical additives and utilities – Transportation costs , including pumping, piping, and trucking – The cost of managing any residuals or byproducts resulting from the treatment of produced water – Permitting, monitoring, and reporting costs
Costs for managing produced water range from $8.00/bbl Costs for managing extracted water should be comparable or higher, due to a possible lack of infrastructure
Final Remarks Water extraction is not required for CCS programs but may be selected to improve operations or ease permitting When water is extracted, the volume is likely to be quite large Management of extracted water poses significant costs and challenges There are various options available for managing extracted water In a water-short world, extracted water may have a role as a new water resource
QUESTIONS?
