Leakage through Existing Wells: Models, Data Analysis, and Lab Experiments

Transcription

1 Leakage through Existing Wells: Models, Data Analysis, and Lab Experiments Michael A. Celia and George Scherer Department of Civil and Environmental Engineering Peter Jaffe Satish Myneni Catherine Peters Jean Prevost Rob Bruant Andrew Altevogt Mileva Radonjic Andre Duguid Sarah Gasda Li Li

2 Outline Overview of activities in 23 Continue focus on leakage and wells. Refocus effort toward detailed studies of well cements. Brief presentation of selected results Analysis of wells and tools for leakage estimation. Unsaturated zone and responses to elevated CO 2. Cement studies (presented by G. Scherer) New laboratory for cement experiments. Design of experiments and preliminary results. Focused activities for CY 24 including local-scale modeling.

3 Mature Sedimentary Basins: Analysis of Wells Viking Formation: 195, Wells Alberta Basin: 35, Wells Very High-Density (Heavy-oil) High- Density Medium- Density Low-Density (Background) Number of clusters Number of wells [% total] Area [% total] Mean intrinsic density [wells/km 2 ]

4 Number of Wells Impacted by typical Injection Mean Median Range High-density clusters Medium-density clusters Low-density Background (Numbers from Gasda et al., 23)

5 CO 2 Injection and Leakage Pathways Shallow-zone Effects Unsaturated Soils Groundwater Resources Numerical Simulations Analytical Solutions Well-leakage dynamics Flow Dynamics Spatial Locations Well Properties Cement Degradation

6 Overview of Selected Results from 23 Simplified Solutions for CO 2 Transport and Leakage Estimation (3 Papers): Analytical solutions to accommodate many potentially leaky wells and multiple geological layers. Framework for linear equations (eg, hazardous waste injection), showing importance of caprock thickness and storage in layers above injection. Energy minimization arguments yield simple equations for evolution of CO 2 plume and pressure field; solution applies to all practical ranges of densities and viscosities (P,T,S) for CO 2 injection in aquifers. Bounding calculations for leakage of brine and CO 2 through leaky well. Comparisons to Eclipse show excellent match of results. Ongoing extensions: Intersecting CO 2 plumes, variable density along the well, redistribution of CO 2 after cessation of injection. Unsaturated Zone Studies (2 Papers) Modeling studies for CO 2 transport: dominant transport mechanisms. Modeling studies of geochemical response to elevated CO 2 concentrations: evolving redox profiles. Laboratory column study for geochemical tests.

7 New Analytical Solutions

8 New Analytical Solution: Two-Phase Flow Analytical solution (sharp interface) versus Effective Saturation from Eclipse Normalized Depth: z/b b( r, t) B Full Numerical Solution (from Eclipse) Analytical Solution 1 λcλwv = λw λc λ 2 w πbr Solution includes unfavorable mobility ratio and gravity r 2 /t override

9 Leakage Solutions

10 Effect of CO 2 Leakage on the Redox Profile in the Vadose Zone Z(m) Z(m) Z(m) O 2 (mole/l) NO 3 (mole/l) x1-2 Mn(IV) (mole/l) x1-4 Z(m) Y(m) Fe(III) (mole/l) x1-4

11 Ongoing Efforts for 24 Leakage Modeling for specific field site: Apply numerical and analytical models to estimate leakage, coupled with well statistics for spatial locations. Determine threshold statistics for well parameters associated with target leakage amounts. Incorporate transient well parameters based on cement degradation estimates. Unsaturated Zone Studies: Continue with laboratory column study. Test models against laboratory data. Well-cement experiments and analysis will be the major effort for 24.

12 General Overview of 23 Topics Covered Analysis of Well Statistics in Viking Formation, Alberta Basin: Gasda, S.E., S. Bachu, and M.A. Celia, "The Potential for CO2 Leakage from Storage Sites in Geological Media: Analysis of Well Distribution in Mature Sedimentary Basins", submitted to Environmental Geology, December 23. Simplified Solutions for CO 2 Transport and Leakage Estimates: Nordbotten, J.M., M.A. Celia, and S. Bachu, "Analytical Solutions for Leakage Rates through Abandoned Wells", revised version submitted to Water Resources Research, December 23. Nordbotten, J., M.A. Celia, and S. Bachu, "Injection and Storage of CO2 in Deep Saline Aquifers: Analytical Solution for CO2 Plume Evolution during Injection", submitted to Transport in Porous Media, October 23. Nordbotten, J., M.A. Celia, S. Bachu, and H.K. Dahle, "Analytical Solution for CO2 Leakage between Two Aquifers through an Abandoned Well", submitted to Environmental Science and Technology, December 23. Large-scale Compositional Simulations: Prevost, J.H., R. Fuller, A.S. Altevogt, R. Bruant, and G. Scherer, Numerical Modeling of Carbon Dioxide Transport in Deep Saline Aquifers: Equation Development, under review, SPEJ, 23.

13 General Overview of 23 Topics Covered Shallow-zone Transport and Geochemisttry: Altevogt, A. and M.A. Celia, "Modeling Carbon Dioxide Transport in Unsaturated Soils", revised version submitted to Water Resources Research, November 23. Altevogt, A.S. and P.R. Jaffe, "Modeling the Effects of Gas-phase CO 2 Intrusion on the Biogeochemistry of Variably Saturated Soils", to appear, Proc. CMWR 24 Conference, June 24. Wang, S. and P.R. Jaffe, Dissolution of Trace Metals in Potable Aquifers due to CO 2 Release from Deep Formations, to appear, Energy Conversion and Management, 24. Giammar, D.E., R.G. Bruant, and C.A. Peters, "Forsterite Dissolution and Magnesite Precipitation at Conditions relevant for Deep Saline Aquifer Storage and Sequestration of Carbon Dioxide, Submitted to Chemical Geology, 23. Upscaling Studies: Gasda, S.E. and M.A. Celia, "Upscaling Relative Permeabilities in a Structured Porous Medium", to appear, Proc. CMWR 24 Conference, June 24. Li, L., C.A. Peters, and M.A. Celia, "Examination of Upscaling Considerations for Geochemical Reaction Rates using Network Model Simulations of Calcite Dissolution", to appear, Proc. 11 th Int. Sym. Rock-Water Interactions, June 24.