Permeability Manipulation and Fluid Control Pillar DOE SubTER Briefing Nov 17, 2015

Multi-Lab Working Group: Co-Leads: Earl Mattson (INL) and Rajesh Pawar (LANL)

Timothy Kneafsey (LBL), Susan Altman (SNL), Joe Morris (LLNL)

Permeability Manipulation Motivation Motivation • Developing methodologies to control fluid flow pathways is critical to achieve Adaptive Control of the Subsurface – Increased fossil/geothermal energy production – Minimization nuclear waste transport – Improving fluids injectivity – Sealing of fractures in the confining layer to prevent fluid leakage

Limited ability to control fluid pathways in heterogeneous media Large permeability contrasts result in: • premature breakthrough of injected fluids, • low resource recovery, • bypassed zones in the subsurface • leakage through cap layers

If fluid pathways can be controlled, benefits to : • Unconventional FE • Improve recovery efficiency • Conventional FE • Improve recovery • Geothermal • Optimize heat extract • Minimize short circuits • NE disposal • Minimize permeability in ‘damage’ zone • CO2 sequestration • Enhance injectivity • Sealing fracture leakage pathways

Creating and Sustaining Uniform Flow Pathways in EGS is critical for Long-term Energy Extraction ”Many of the key energy challenges of the

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future will require not only that we can understand and manipulate complex materials in the laboratory, but also in their geologic context, typically at elevated temperatures and pressures and large length and time scales, and commonly in remote locations kilometers below the Earth’s surface” Controlling Subsurface Fractures and Fluid Flow: A Basic Research Agenda, 2015

An Engineered Geothermal System will require 30 years of sustained high temperature and flow rate – The injected flow must be divided evenly between the fractures – The flow must be uniform within each fracture – These conditions must be maintained for 30 years.

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Solving this problem will require a cross-cut effort between all pillars: – Wellbore technology – Stress control to create uniform fractures – Permeability manipulation of the fractures – New signal to understand flow pathways

Manipulating Permeability: State-of-the-Art develop the scientific basis and technologies to quantify, characterize and manipulate subsurface flow through an integration of physical alterations, physicochemical fluid/rock interaction processes, and novel stimulation methods implemented at the field scale

Pillar Objective State of Art • Current permeability enhancement methods have also created unintended consequences. • Hydraulic fracturing to create permeability in low permeable reservoirs has been wildly successful, yet our knowledge is limited: • Controls on fracture initiation & growth • Spatial distribution, extent of fractures • Engineering lifetime of stimulated fractures • Controls on the distribution of flow within and between fractures and rock/fluid interactions • Technologies to enhancing and/or reducing fluid flow have been deployed with mixed success in both porous and fracture media: • Limited success on predicting and controlling • Our ability to effectively deliver materials at target locations is limited •

Alternate hydraulic fracturing technologies have shown limited success

(Duenckel, R, et.al, 2011)

Permeability Manipulation and Fluid Control

10 Year Element Goals

Manipulating Physicochemical Fluid-Rock Interactions

 Manipulate field scale fluid flow using improved understanding of coupled THMCB processes and quantitative modeling to predict how to change fluid flux magnitude and flow pathways to meet subsurface engineering objectives.

Manipulating Flow Paths to Enhance/Restrict Fluid Flow

 Manipulate fluid fluxes and pathways at the fracture scale that affect subsurface engineering objectives.

Characterizing Fracture, Dynamics and Fluid Flow

Novel Stimulation Technologies

 Provide methodologies to determine fracture/flow characteristics in the field and potential signals to improve fracture/flow mapping

 Deploy a method other than hydraulic fracturing to industry for an engineering extraction application. .

Manipulating Physicochemical Fluid-Rock Interactions’ Element Well controlled laboratory experiments to field

2 year goals

5 year goals

10 year goal

Predict rock/fluid/fracture interactions for well constrained laboratory tests

Demonstrated the ability to predict and manipulate flow in laboratory-scale fine-grained rock experiments

Up-scaling of laboratory observations to field scale

Demonstrate applicability of novel upscaling approaches for laboratory observations

Design a field-scale test of flow manipulation

Manipulate field scale fluid flow using coupled THMCB processes

Metric of success – 10% improvement of engineering performance over current practices

Example FY16-FY18 Activity, Physiochemical Element:

Characterize key physicochemical/mechanical /biological controls on flow in fractured rocks. Quantitatively describe relationships between the injected fluid chemistry, geochemistry and subsurface mechanical response in fractured crystalline and fine grained sedimentary rocks.

• Fundamental understanding at; – molecular level, – pore scale, – to laboratory scale

• Apply understanding to engineering scale

‘Characterizing Fracture, Dynamics and Fluid Flow’ Element Characterizing Fracture Flow

2 year goals

5 year goal

10 year goal

Improve performance of existing fracture flow characterization approaches through integrated laboratory and field experiments and numerical modeling.

Developing New Detection Methods Identify new signals for 1) fracture dynamics characteristics and 2) characterization technologies through integrated laboratory characterization and field testing coupled with numerical modeling

Develop and demonstrate methodologies to: 1) determine flow in fractures, 2) quantify fractures and 3) predict fracture dynamics at pilot scale field scale demonstrations

Provide methodologies to determine fracture/flow characteristics in the field and potential signals to improve fracture/flow mapping.

Metric of success - Improve the accuracy and sensitivity of fracture/flow characterization technologies by 50 % over existing technologies

Example FY16-FY18 Activity, Characterizing Fractures, Dynamics and Fluid Flow Element

Development of micro-sensors, reactive tracers, and phase-changing tracers that provide new fracture characterization capabilities • Understanding tracer characteristics in the subsurface • Designing new thermally degrading tracers to optimize sensitivity to geothermal conditions • Novel application methods

Example FY16-FY18 Activity, Characterizing Fractures, Dynamics and Fluid Flow Element

Development and validation of fracture network/fluid flow reservoir simulators that a mechanistic representations of hydrocarbon production, CO2 leakage, heat extraction and radionuclide transport allowing for predictive capability

• New numerical methods to simulate fracture propagation • New methods to describe reservoir/fracture flow • Laboratory/Pilot scale testing facilities to validate network/flow models

SPH-Proppant Transport

Permeability Manipulation and Fluid Control Important for Success of Other Pillars Element

Wellbore Stress

New Signals

Manipulating Physicochemical FluidRock Interactions

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Manipulating Flow Paths to Enhance/Restrict Fluid Flow

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Characterizing Fracture, Dynamics and Fluid Flow

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Novel Stimulation Technologies

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Sapling Project Associated with Pillar kISMET (Deep Mine Fracture & Flow) kISMET = permeability (k) and Induced Seismicity Management for Energy Technologies

• Stress measurements and modeling of the stress state in crystalline rock • Small to intermediate-scale stimulation (hydraulic fracturing) • Permeability and tracer transport flow testing • Active seismic and electrical monitoring experiments • Integrated laboratory studies • Hydro-geomechanical modeling of the stress field and fracture generation

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Summary • Our ability to engineer permeable pathways in the subsurface has surpassed our scientific understanding of how to maximize the benefits. • ‘Adaptive control’ of the subsurface requires developing the scientific underpinning to manipulate permeability and control fluid pathways • Scaling this fundamental understanding to field-scale solutions is critical to maximize engineering objectives while minimizing the environmental impact

• Extra slides

‘Manipulating Flow Path to Enhance/Reduce Flow’ Element

2 year goals

5 year goals

10 year goal

Demonstrate relationship between fracture characteristics and fluid flow in fine-grained rock at laboratory scale

Demonstrate adaptive control of enhanced and reduced fluid flow in fractured fine-grained rocks at laboratory scale

Evaluate effectiveness of chemical, geochemical & hydrodynamic strategies for improving and/or sustaining useful fracture permeability

Demonstrate predictive capability for behavior of permeability reducing/enhancing materials and methods against field observations

Manipulate fluid fluxes and pathways at the fracture scale that affect subsurface engineering objectives.

Metric of success – Demonstrate 10% enhancement in production in pilot test, Demonstrate 50% reduction in permeability in pilot test

Example FY16-FY18 Activity, Manipulating Flow Paths Element:

Validate predictive capabilities for fracture initiation, propagation, branching and flow against laboratory observations • Laboratory experiments (multi-scale, multi-rock types) on rock fracturing • Novel predictive approaches for fracture initiation, propagation, branching and flow • Link from laboratory results to larger field scale

Experimental observations of shale fracturing

Numerical simulation of fracturing

‘Novel Stimulation Technologies’ Element Water-less fracturing Demonstrate effectiveness of one waterless fracturing method at laboratory scale

2 year goals

5 year goal

10 year goal

Develop novel, fluid-less fracturing methods (e.g., explosives, energetics, electro-fracturing) and assess effectiveness

Better hydraulic fracturing Identify novel approaches to improve effectiveness of traditional hydraulic fracturing technique Identify novel fluid based stimulation methods

Demonstrate in the field application of water-less and fluid-less fracturing fluids. Investigate new methods to “design” fracture networks.

Deploy a method other than hydraulic fracturing to industry for an engineering extraction application.

Metric of success – Demonstrate improve engineering performance of a novel stimulation technology over conventional hydraulic fracturing

Metrics for success • Validated simulation capabilities of fracture initiation, propagation and resulting permeability against laboratory observations in shale samples • Demonstration of 50% flow reduction by chemical manipulation in the laboratory • Demonstration of chemical methods for fracture surface area characterization in laboratory • Develop a laboratory method to control fracture initiation and growth

Pillar Objective and Elements Permeability Manipulation and Fluid Control Manipulating Physicochemical Fluid-Rock Interactions

Manipulating Flow Paths to Enhance/Restrict Fluid Flow

Characterizing Fracture, Dynamics and Fluid Flow

Novel Stimulation Technologies

Fundamental understanding of the THMCB interactions between the injected fluid, pore fluids and minerals Manipulate fracture-scale fluid fluxes and flow pathways

Characterizing fracture/flow and identifying potential signals to improve fracture/flow mapping

Alternative waterless hydraulic fracturing methods