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Large-scale CO injection problems have revived the interest in simple models, like percolation and vertically-averaged models, for simulating fluid flow in reservoirs and aquifers. A series of such models have been collected and implemented together with standard reservoir simulation capabilities in a high-level scripting language as part of the open-source MATLAB Reservoir Simulation Toolbox (MRST) to give a set of simulation methods of increasing computational complexity. Herein, we outline the methods and discuss how they can be combined to create a flexible tool-chain for investigating CO storage on a scale that would have significant impact on European CO emissions. In particular, we discuss geometrical methods for identifying structural traps, percolation-type methods for identifying potential spill paths, and vertical-equilibrium methods that can efficiently simulate structural, residual, and solubility trapping in a thousand-year perspective. The utility of the overall workflow is demonstrated using real-life depth and thickness maps of two geological formations from the recent CO Storage Atlas of the Norwegian North Sea. [ABSTRACT FROM AUTHOR]

Geological carbon storage represents a new and substantial challenge for the subsurface geosciences. To increase understanding and make good engineering decisions, containment processes and large-scale storage operations must be simulated in a thousand year perspective. A hierarchy of models of increasing computational complexity for analysis and simulation of large-scale CO storage has been implemented as a separate module of the open-source Matlab Reservoir Simulation Toolbox (MRST). This paper describes a general family of two-scale models available in this module. The models consist of two-dimensional flow equations formulated in terms of effective quantities obtained from hydrostatic reconstructions of vertical pressure and saturation distributions. The corresponding formulation is fully implicit and is the first to give a mass-conservative treatment and include general (non-linearized) CO properties. In particular, the models account for compressibility, dissolution, and hysteresis effects in the fine-scale capillary and relative permeability functions and can be used to accurately and efficiently study the combined large-scale and long-term effects of structural, residual, and solubility trapping. [ABSTRACT FROM AUTHOR]

Modeling geological carbon storage represents a new and substantial challenge for the subsurface geosciences. To increase understanding and make good engineering decisions, containment processes and large-scale storage operations must be simulated in a thousand-year perspective. Large differences in spatial and temporal scales make it prohibitively expensive to compute the fate of injected CO using traditional 3D simulators. Instead, accurate forecast can be computed using simplified models that are adapted to the specific setting of the bouyancy-driven migration of the light fluid phase. This paper presents a family of vertically integrated models for studying the combined large-scale and long-term effects of structural, residual, and solubility trapping of CO. The models are based on an assumption of a sharp interface separating CO and brine and can provide a detailed inventory of the injected CO volumes over periods of thousands of years within reasonable computational time. To be compatible with simulation tools used in industry, the models are formulated in a black-oil framework. The models are implemented in , which is an open community software developed especially to study and optimize large-scale, long-term geological storage of CO. The resulting simulators are fully implicit and handle input from standard geomodeling tools. [ABSTRACT FROM AUTHOR]