produced water | session ix - hayes
DESCRIPTION
Shale Gas Water Modeling and Sustainability PlanningTRANSCRIPT
Shale Gas Water Modeling and Sustainability Planning
Atlantic CouncilProduced Water Workshop
Washington D.C.June 24-25, 2013
Tom HayesEnvironmental Engineering Gas Technology Institute
22
An AssertionThe sustainable production of energy from shale gas wells is dependent on the economics and environmental impact of water and solid waste management.
33
Today’s Discussion
Variable and Complex Nature of Shale Gas Industry Operations
Large Opex Expenditures Involved in Movement of Water and Wastes
Life Cycle Modeling Tracks Rollups of Large Mass Flows and Offers Capability to Predict Future Challenges and Solutions
Examples of Year By Year Variable Flows of Water, Salts and Solid Waste
Future Outlook: Life Cycle Analysis Importance to Sustainability Planning
44
Nature of the Shale Gas Industry: Dynamic – Not Steady State
Not like Brick and Mortar Factories
Total Life Cycle of Development Areas: 30 to 50 yrs
Substantial Year-by-year changes: Numbers of wells drilled (ramp up/plateau/ramp down) Perturbations in pace of development (e.g. var rig counts)
Changing Water and Solid Waste Outputs Changing Regional Demands Year by Year
Water Transportation Infrastructure
55
Variable Annual Impacts
Demand for fresh water Water storage footprint Transportation of water
Truck Traffic Air Emissions Carbon Footprint Road Wear & Damage
Noise Wildlife Well Field Air Emissions (Very Transient)
VOC Emissions from hydraulic fracturing sites. MACT Emissions from On-Site Diesels
66
Potential Regional Constraints to Shale Gas Development
Droughts (e.g. Barnett, Eagle Ford, Western Shale Gas Plays)
Need: > 4 MG per horizontal well completion Water sourcing often competes with community
supplies
Lack of Class II well disposal for brines (e.g. Marcellus, Western Shale Gas Plays)
Increases transportation distances and costs
Perceived & Real Environmental Impacts Increased Regulatory Pressures
Watershed allocations of water USEPA: VOC Issues / Fracking Impacts
7
Water Based Life Cycle Model Tracking of a Dynamic System
Brine GenerationSolid Waste OutputSalt OutputEnviron ImpactsWater Demands
Data-Driven Decisions for ImprovedLong Term Planning
Water Based LifeCycle Model
Useful Projections
Flowback and PWGeneration and Characteristics
Well Drilling &HF Schedules
Water ReuseOpportunities
Water Treatment& Disposal
Options
Uncertainties& Real Time Data
Analysis
88
Life Cycle Analysis
• Purpose: Examine long term (30+ years) water management strategies for a development area.
• Approach: Use field data (from more than 25 well locations) and current management practices to project water reuse capacity, water generation, salt generation, solid waste output and salt concentration profiles
• Spreadsheet Model was developed to simulate year by year water and solid waste flows & characteristics through the life cycle of a development area
9
1010
Typical Flowback Water Characteristics
0 10 20 30 40 50 60 70 80 90 1000
50000
100000
150000
200000
Days from Hydraulic Fracture Event
Flowback Water Total Dissolved Solids, mg/l
1000
0
3000
Ave
Flo
w* in
the
Inte
rva
l, Bb
l/d
200014 - 90 DayInterval
•Average Daily Flow of the Flowback Water Output within Each Interval
1111
Example Run of the Model
More than 30 Data Inputs
Base case assumed:• County size development area • 300 Well Fields, 16 Wells/Field 4800 wells, • Completion + 3 refractures per well (3 yr spacing)• 33% Reuse Water/ Total Fracture Volume• Ave PW generation = 7 bbl/d
Results:• Cross Over starts going critical in year 12• Logistical difficulty with reuse in about a decade
1212
Water-based Life Cycle (Marcellus Shale)
CrossoverPoint
Good Level ofWater ReuseOpportunities
DiminishedWater ReuseOpportunities
2/3 of salt output
13
0 5 10 15 20 25 30 35 40 45 500
100
200
300
400
500
600
700
800Flowback + Produced Water (Cumulative Volumes)
3 Refractures
2 Refractures
1 Refracture
0 Refractures
Years
Cu
mu
lati
ve
Ba
rre
ls (
mil
lio
n)
Cumulative Water Output from a Development Area
Shaded Area = Post Crossover
14
0 5 10 15 20 25 30 35 40 45 500
5,000
10,000
15,000
20,000
25,000
30,000
35,000
40,000
45,000Produced Salt
3 Refractures
2 Refractures
1 Refracture
0 Refractures
Years
Cu
mu
lati
ve
Sa
lt,
Mil
lio
ns
Po
un
ds
Cumulative Salt Output from a Development Area
Shaded Area = Post Crossover
Planning Issue?
15
Annual Solid Waste Output from a Development Area
Residential Solid Waste Generation from AvePA County
LF Planning Issue?
1616
GTI Life Cycle Analysis Model Addresses Multiple Dynamic Issues
Flowback and Produced Water Management Timing of Issues and Required Changes in Water
Management Predicting Regional Infrastructure Required to
Support Shale Gas Industry Growth Road Wear / Traffic Landfill Capacity Plans and Alternative Solutions
Regional Environmental Impact in Future Years Wellfield Emissions: VOC / GHG / NOx Transportation Impacts: MACT Other Environmental Impacts
1717
GTI Life Cycle Model Development Continues
Customized Database Management for Flowback and Produced Water Management
GIS Positioning Data Inputs
VOC Data Management, Forecasts of Emissions and Atmospheric Model Interface
Wellfield Gas Generation Data vs. Time
Probabilistic Analysis to Manage Data Limitations, Uncertainties, and Risk.
Multi-client program. Seeking cooperators/supporters.
1818
Summary
Shale Gas: Dynamic - Not Steady State There Are Substantial Year-by-year changes:
Numbers of wells drilled (ramp up/plateau/ramp down) Non-steady pace of development (e.g. var rig counts)
There are Changing Water & Solid Waste Outputs Regional Demands Change from Year to Year
Water / Transportation / Infrastructure / Landfills
GTI’s Life Cycle Model is Data Driven, and an Effective Decision Tool to Improve Planning for Sustainable Shale Gas Development - Valuable to Industry, Policy Makers, and Regional Planners.
Thank You
Tom Hayes Environmental EngineeringGas Technology [email protected]
Trevor Smith Business DevelopmentGas Technology [email protected]