Abstract
The current situation with green gas emission requires the development of low-carbon energy solutions. However, a significant part of the modern energy industry still relies on fossil fuels. To combine these two contradictory targets, we investigate a strategy based on a combination of CO2 sequestration with enhanced oil recovery (EOR) in the hydrocarbon reservoirs. In such technology, the development of miscibility is the most attractive strategy from both technological and economic aspects. Modeling of this process involves solving complex nonlinear problem describing compositional flow and transport in highly heterogeneous porous media. An accurate capture of the miscibility development usually requires an extensive number of components to be present in the compositional problem which makes simulation run-time prohibitive for optimization. Here, we apply a multi-scale reconstructing of compositional transport to the optimization of CO2 injection. In this approach, a prolongation operator, based on the parametrization of injection and production tie-lines, is constructed following the fractional flow theory. This operator is tabulated as a function of pressure and pseudo-composition which then is used in the operator-based linearization (OBL) framework for simulation. As a result, a pseudo two-component solution of the multidimensional problem will match the position of trailing and leading shocks of the original problem which helps to accurately predict phase distribution. The reconstructed multicomponent solution can be used then as an effective proxy-model mimicking the behavior of the original multicomponent system. Next, we use this proxy-model in the optimization procedure which helps to improve the performance of the process several fold. An additional benefit of the proposed methodology is based on the fact that important technological features of CO2 injection process can be captured with lower degrees of freedom which makes the optimization solution more feasible.
Highlights
Greenhouse gas emission together with a high demand of energy has long been a concern of contemporary society
We extend the multi-scale reconstruction in physics (MSRP) approach for the equation of state (EoS)-based gas injection problems
The obtained proxy model can accurately predict the boundaries of the two-phase region and has been utilized in this work for production optimization in a simplified physical assumptions of the forward problem
Summary
Greenhouse gas emission together with a high demand of energy has long been a concern of contemporary society. Coupling with chemical reactions requires a combination of thermodynamic and chemical equilibria [17, 24] This can significantly increase the cost of phase-behavior computations in compositional simulation [34]. On the basis of these ideas, an MSRP method for reconstruction of the compositional transport problem with an arbitrary number of components was developed in [6] This approach suggests a two-stage reconstruction, where, at the first stage, the boundary of a two-phase region is recovered, and the detailed solution in the two-phase region is reconstructed in the second stage. The state-dependent operators are adaptively discretized in the parameter space of the problem, and multi-linear interpolation is applied for continuous representation [13] This formulation helps to avoid the performance issues associated with an accurate phase-split evaluation and reduces the nonlinearity of the problem. A concise simulation framework based on [36] is presented
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
