HR: 1330h
AN: GC32A-0205    [PDF]
TI: CIRF.B Reaction-Transport-Mechanical Simulator: Applications to CO2 Injection and Reservoir Integrity Prediction
AU: * Park, A J
EM: ajpark@rtm-geodynamics.com
AF: Geo-Chemical Research Assoc., Inc., POBox 894, Bloomington, IN 47403 United States
AU: Tuncay, K
EM: ktuncay@indiana.edu
AF: Dept. of Chemistry, Indiana University, Bloomington, IN 47405 United States
AU: Ortoleva, P J
EM: ortoleva@indiana.edu
AF: Geo-Chemical Research Assoc., Inc., POBox 894, Bloomington, IN 47403 United States
AU: Ortoleva, P J
EM: ortoleva@indiana.edu
AF: Dept. of Chemistry, Indiana University, Bloomington, IN 47405 United States
AB: An important component of CO2 sequestration in geologic formations is the reactions between the injected fluid and the resident geologic material. In particular, carbonate mineral reaction rates are several orders of magnitude faster than those of siliciclastic minerals. The reactions between resident and injected components can create complex flow regime modifications, and potentially undermine the reservoir integrity by changing their mineralogic and textural compositions on engineering time scale. This process can be further enhanced due to differences in pH and temperature of the injectant from the resident sediments and fluids. CIRF.B is a multi-process simulator originally developed for basin simulations. Implemented processes include kinetic and thermodynamic reactions between minerals and fluid, fluid flow, mass-transfer, composite-media approach to sediment textural description and dynamics, elasto-visco-plastic rheology, and fracturing dynamics. To test the feasibility of applying CIRF.B to CO2 sequestration, a number of engineering scale simulations are carried out to delineate the effects of changing injectant chemistry and injection rates on both carbonate and siliciclastic sediments. Initial findings indicate that even moderate amounts of CO2 introduced into sediments can create low pH environments, which affects feldspar-clay interactions. While the amount of feldspars reacting in engineering time scale may be small, its consequence to clay alteration and permeability modfication can be significant. Results also demonstrate that diffusion-imported H+ can affect sealing properties of both siliciclastic and carbonate formations. In carbonate systems significant mass transfer can occur due to dissolution and reprecipitation. The resulting shifts in in-situ stresses can be sufficient to initiate fracturing. These simulations allow characterization of injectant fluids, thus assisting in the implementation of effective sequestration procedures.
DE: 1000 GEOCHEMISTRY (New field, replaces Rock Chemistry)
DE: 1010 Chemical evolution
DE: 1020 Composition of the crust
DE: 1045 Low-temperature geochemistry
SC: Global Climate Change [GC]
MN: 2003 Fall Meeting