EOS Component Lumping Optimization

Author: Arnaud Hoffmann To reduce CPU time in compositional petroleum simulation models (e.g. compositional reservoir simulations), a minimum number of components should be used in the equation of state (EOS) to describe the fluid phase and volumetric behavior. A ″detailed” EOS model often contains from 20 to 40 components, with the first 10 components representing […]

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Answers to Questions at SPE IOR 2020

SPE-200396: Gas EOR Processes in Tight Unconventionals Q1) Why did you select the “minimum dimension” instead of “surface to volume ratio” to explain the dependence of the oil-recovery results on sample size. Hassan Dehghanpour (University of Alberta) We believe that the minimum dimension is easier to understand and relate to than the surface-to-volume ratio (S/V). […]

Black-Oil and Compositional Reservoir Simulation of Gas-Based EOR in Tight Unconventionals

Author: Stian Mydland *This is a short-version of URTEC-2020-2765-MS presented at Unconventional Resources Technology Conference (URTeC) 2020. Paper can be downloaded in the end of this article. Reservoir simulation requires a fluid model to describe the volumetric behavior of gas and oil. When initiating a reservoir simulation study, we have to choose whether to use […]

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Single Phase Labeling in Compositional Simulators

Author: Bilal Younus The term “single phase labeling” means to determine whether the given total composition zi (in a specific grid cell in the model) exists as single-phase “oil” or single-phase “gas” when the grid cell pressure is higher than the saturation pressure ps = f(zi,T), where T is the temperature in the model. A […]

Collaborating with ResFrac on Advanced Black Oil PVT

Author: Mathias Carlsen Most reservoir engineering analysis in the petroleum industry is performed utilizing black oil tables. In general, there are three different types of black oil tables: (1) traditional, (2) modified and (3) extrapolated. These are visually presented in the figure above and becomes more “sophisticated” as we move from left to right. Traditional […]

Condensate Blockage – a short introduction to gas condensate well modeling

Author: Erlend Torheim It is important to understand and model the reduction in well deliverability due to condensate blockage in gas condensate wells. Failing to do so can lead to inappropriate design of (a) well completion, (b) number of wells required for development, and (c) compression requirements – all having a significant bottom-line impact on […]

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What is an Equation of State?

Author: Markus Hays Nielsen Most petroleum engineers understand that engineering calculations require the properties of fluids. “Fluid” is a term used to describe gases and liquids. An equation of state (EOS) is nothing more than a fluid model. Specifically, an EOS is a fluid model that takes a molar composition (z) and predicts the phase […]

Gas EOR Processes in Tight Unconventionals

Author: Stian Mydland *This is a short-version of SPE-200396-MS to be presented at SPE Increased Oil Recovery Conference 2020, Tulsa, OK, USA. Gas-Based EOR in Tight Unconventionals Gas-based EOR is currently being pilot-tested extensively in liquid-rich North-American tight unconventionals with the majority of projects using the Huff-n-Puff (HnP) method. This method differs from conventional displacement […]

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CGR Normalization – Convert Rates to a Common Surface Process

Author: Mathias Lia Carlsen * This is a short-version of SPE-199982-MS that will be presented on the SPE Canada Unconventional Resources Conference 18 March 2020 in Calgary, Canada. The manuscript can be found attached to this blog post. CGR Normalization – What is it?Black oil tables are generated assuming a fixed surface process, but in […]

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