Abstract: A method for improved prediction and enhancement of hydrocarbon recovery from ultra-tight/unconventional reservoirs for both the primary production and any subsequent solvent huff‘n’puff periods based on facilitating the diffusion process may include steps of defining one or more initial properties of a reservoir and integrating characterization data of the reservoir; defining a wellbore trajectory for each of at least one well and one or more parameters associated with a completion/reservoir stimulation design; specifying operating conditions for a current development cycle; performing diffusion-based dynamic fracture/reservoir simulation for calculating hydrocarbon recovery and efficiency of a hydrocarbon process; and; determining whether to commence or continue enhanced oil recovery (EOR) or enhanced gas recovery (EGR) cycles.

Abstract: A method for improved prediction and enhancement of hydrocarbon recovery from ultra-tight/unconventional reservoirs for both the primary production and any subsequent solvent huff'n'puff periods based on facilitating the diffusion process may include steps of defining one or more initial properties of a reservoir and integrating characterization data of the reservoir; defining a wellbore trajectory for each of at least one well and one or more parameters associated with a completion/reservoir stimulation design; specifying operating conditions for a current development cycle; performing diffusion-based dynamic fracture/reservoir simulation for calculating hydrocarbon recovery and efficiency of a hydrocarbon process; and; determining whether to commence or continue enhanced oil recovery (EOR) or enhanced gas recovery (EGR) cycles.

Abstract: The technology extends hyperbolic-lipophilic difference and net average curvature (HLD-NAC) to a robust algorithm for predicting the phase behavior of microemulsions at different conditions away from experimental results. The HLD-NAC equations are modified to ensure consistency over the entire composition space including type II? and II+ regions. The algorithm converges and provides continuous estimates with any formation variable of tie lines and triangles for all Winsor types. The algorithm is configured such that discontinuities are eliminated and limiting tie lines near critical points are determined analytically. The algorithm is tuned using several sets of experimental data and provides for predictability of tie lines and tie triangles, and solubilization ratios.

Abstract: A compositional simulator that is fully compositional and more robust and accurate is disclosed. Relative permeability (kr) and capillary pressure (Pc) are modeled as state functions, making them unique for a given set of inputs, which can include Euler characteristic, wettability, pore connectivity, saturation, and capillary number. All of these are made to be a function of composition, T, and P or rock properties. These state function kr-Pc models are fully compositional and can fit experimental data, including complex processes such as hysteresis. The models can be tuned to measured relative permeability data, and then give consistent predictions away from that measured data set. Phase labeling problems are eliminated. Flux calculations from one grid block to another are based on phase compositions. Simulations for three or four-phase hydrocarbon phases are possible. Time-step sizes increase to stability limits of implicit-explicit methods.

Abstract: The HLD-NAC model was recently modified to match and predict microemulsion phase behavior experimental data for Winsor type III regions. Until now, the HLD-NAC model cannot generate realistic phase behavior for type II? and type II+ two-phase regions, leading to significant saturation and composition discontinuities when catastrophe theory is applied. These discontinuities lead to significant failures in modeling surfactant applications. The HLD-NAC equations are modified to ensure consistency over the entire composition space including type II? and II+ regions. A robust and efficient algorithm is developed that always converges and provides continuous estimates with any formation variable of tie lines and triangles for all Winsor types. Discontinuities are eliminated and limiting tie lines near critical points are determined analytically. The tuning procedure is demonstrated using several sets of experimental data. Excellent predictability of tie lines and tie triangles, and solubilization ratios are shown.