Gas Hydrates: Energy and the Environment A Rice Initiative Walter G. Chapman Chemical Engineering Dept. Rice University RICE www.gashydate.de/images/hand.jpg US UNIVERSITY Geological Survey 1 What are Gas Hydrates? Self-assembled nano-structures formed by the cooperative hydrogen bonding of water molecules to create polyhedron cages around small molecules. Methane trapped in a single Pentagonal Dodecahedra Cage From US Geological Survey. Comparison of ice and hydrate structures. One of the hydrate cages is shown to contain a methane molecule. From the Naval Research Laboratory RICE http://dusk.geo.orst.edu/oceans/lec14.html UNIVERSITY 2 Why are Hydrates Interesting? • Pipeline Plugging • Preventing Gas Hydrate formation accounts for • 10-15% of the production costs • $500 Million per year for inhibitors alone RICE www.spe.org/cda/images/ hydrate.jpg UNIVERSITY 3 Where Else Do Hydrates Form? • In sediments below the ocean floor http://marine.usgs.gov/fact-sheets/gas-hydrates/title.html RICE UNIVERSITY 4 Seismic and Photo Evidence Seafloor BSR RICE Images: Trehu et al., 2002 UNIVERSITY 5 RICE UNIVERSITY 6 Why are Hydrates Interesting? • Potential Fuel Source • Methane Hydrate is stable on land in polar regions and at sea in water deeper than a few hundred meters, and likely exists on all continental margins. The triangles here show actual discoveries (updated from Kvenvolden, 1988). (From Naval Research Lab) RICE UNIVERSITY 7 Distribution of organic carbon in Earth reservoirs (excluding dispersed carbon in rocks and sediments). Numbers in gigatons (1015 tons) of carbon Ocean 983 (e.g., dissolved organics, and biota Atmosphere 3.6 Land 2790 (Includes soil, biota, peat and detritus 1 Fossil Fuels 5,000 Data from USGS 2 Gas hydrates 3 4 10,000 5 RICE UNIVERSITY 8 Why are Hydrates Interesting? • Climate Change and Seafloor Stability Potential Release of Greenhouse Gases hydrate.eas.gatech.edu/gthydrates/ schemclimate.gif RICE UNIVERSITY 9 Why are Hydrates Interesting? • Gas Hydrate Applications • • • • • • • Flow Assurance Energy Production Seafloor Stability Global Climate Change Transport and Storage of Natural Gas Gas Separations and Materials Handling Templates for Nano-Materials RICE UNIVERSITY 10 Rice Hydrates Team Organized Under the Shell Center for Sustainability, Exec. Director Chris Holmes • • • • • Energy Production from Gas Hydrates Flow Assurance Seafloor Stability Global Climate Change Public Policy with the Baker Institute RICE UNIVERSITY 11 Molecular to Global Scale Molecular Mechanisms and Dynamics • NMR/MRI Mechanisms and Dynamics – Chapman (Chem. E.) and House (Texas Tech) • Molecular Simulation – Chapman (Chem. E.) • Properties at High Pressure – Chapman (Chem. E.) • X-ray Crystal Structure – Billups (Chemistry) • Gas Hydrate Kinetics – Bishnoi (Calgary) • Applications to • Hydrate Inhibition for Flow Assurance • Hydrate Dynamics for Resource Modeling RICE UNIVERSITY 12 Molecular to Global Scale Hydrate Resource Characterization • Core and Species Analysis – Dickens (Earth Science) • NMR Well Logging – Hirasaki and Chapman (Chem. E.) and House (Texas Tech) • Seismic Interpretation – Zelt and Sain (Earth Science) • Geologic Scale Simulation – Hirasaki and Chapman (Chem. E.) • Resource Interpretation – Dugan (Earth Science) • Applications to • Locating High Concentrations of Hydrates • Characterizing the Hydrate Resource RICE UNIVERSITY 13 Molecular to Global Scale Hydrate Resource Dynamics • Species Analysis and Interpretation – Dickens (Earth Science) • Production Technology – Hirasaki (Chem. E.) • Heat Transfer – Bayazitoglu (Mech. E.) • Reservoir Simulation for Production – Mohanty (Univ. of Houston) • Slope Failure – Spanos (Mech. E.) • Applications to • Energy Production and Seafloor Stability • Global Climate Change RICE UNIVERSITY 14 Hydrate Research at Rice Rice Team Members Yildiz Bayazitoglu (Mech. Engr.) Ed Billups (Chemistry) Walter G. Chapman (Chem. Engr.) Jillene Connors (Baker Institute) Jerry Dickens (Earth Science) Brandon Dugan (Earth Science) George Hirasaki (Chem. Engr.) Chris Holmes (Shell Center for Sustainability) Amy Jaffe (Baker Institute) Paul Spanos (Mech. Engr.) Colin Zelt (Earth Science) Other Team Members Raj Bishnoi (Univ. of Calgary) Waylon House (Texas Tech) Kalachand Sain (Nat. Geophys. Res. Inst., India) Kishore Mohanty (Univ. of Houston) RICE UNIVERSITY 15 Business Opportunities • Flow Assurance Strategies and Detecting Hydrates • Seafloor Stability • Near Wellbore Failure • Slope Failure • Energy Production • Global Climate Change RICE UNIVERSITY 16 Rice University RICE UNIVERSITY 17 Production Issues • High Concentration of Hydrates • Production Strategy Depends on Accumulation Process • Seafloor Stability • Reservoir Model (Accumulation and Production) • • • • • Reservoir Heterogeneity Lithology and Permeability of the formation Brine Flux Heat Effects and Thermal Conductivity Mechanism and Rate of Dissociation RICE UNIVERSITY 18 Production Response • Possible Production from Messoyakha Field • Possibly 36% of the production (5 billion m3) from hydrates (Makogan, 1981) • Nankai Trough – Southeastern Coast of Japan • Mallik Production Test (Northern Coast of Canada) • Hot Ice 1 – North Slope of Alaska – Anadarko in Collaboration with DOE RICE UNIVERSITY 19 Production Technologies • Pressure Depletion • Free Gas Production Produced Gas Sea floor Hydrate Containing Sediment “Free” Gas RICE UNIVERSITY 20 Why are Hydrates Interesting? • Seafloor Stability Model for seafloor stability at the gas hydrate stability limit from Booth, J.S., Winters, W.J. and Dillon, W.P., 1994. http://www.nrlssc.navy.mil/~hydrates/Research.htm RICE UNIVERSITY 21 Why are Hydrates Interesting? • Seafloor Stability http://www.nrlssc.navy.mil/~hydrates/Research.htm RICE UNIVERSITY 22