Chemical Enhanced Oil Recovery and the Dilemma of More and Cleaner Energy

We develop a method based on concept of exergy-return on exergy-investment (ERoEI) to determine the energy efficiency and CO₂ footprint of polymer and surfactant enhanced oil recovery (EOR). This integrated approach considers main surface and subsurface elements of the chemical EOR methods. The main energy investment in oil...

CO₂Foam Behavior in Carbonate Rock: Effect of Surfactant Type and Concentration

An understanding of how CO2 foam flows through a reservoir rock is useful for many subsurface applications, including enhanced oil recovery and CO2 storage. There are economic and environmental benefits in identifying surfactants that exhibit good foaming behavior with CO2 at both low concentrations and high foam qualities. Core flood...

Chemical enhanced oil recovery and the dilemma of more and cleaner energy

A method based on the concept of exergy-return on exergy-investment is developed to determine the energy efficiency and CO₂ intensity of polymer and surfactant enhanced oil recovery techniques. Exergy is the useful work obtained from a system at a given thermodynamics state. The main exergy investment in oil recovery by water...

Insights into Effects of Surfactant Concentration on Foam Behavior in Porous Media

A potential solution to mitigate the adverse effects of viscous fingering, gravity override, and reservoir heterogeneity on the efficiency of gas injection in porous media is to inject the gas with a solution containing surface-active agents such as surfactants or nanoparticles. The efficiency of these processes largely depends on the generation...

Life-cycle production optimization of hydrocarbon fields: Thermoeconomics perspective

We suggest alternative objective functions based on the concept of thermoeconomics (or exergoeconomics) that could be used for simultaneous maximization of economics and energy efficiency of oil-production systems. The suggested functions are evaluated for an oil reservoir, where water is injected to improve its recovery factor. We find that...

Insights into Effects of Surfactant Concentration on Foam Behavior in Porous Media

A potential solution to mitigate the adverse effects of viscous fingering, gravity override, and reservoir heterogeneity on the efficiency of gas injection in porous media is to inject the gas with a solution containing surface-active agents such as surfactants or nanoparticles. The efficiency of these processes largely depends on the generation...

Experimental Study of Hysteresis behavior of Foam Generation in Porous Media

Foam can be used for gas mobility control in different subsurface applications. The success of foam-injection process depends on foam-generation and propagation rate inside the porous medium. In some cases, foam properties depend on the history of the flow or concentration of the surfactant, i.e., the hysteresis effect. Foam may show...

Determination of lower and upper bounds of predicted production from history-matched models

We present a method to determine lower and upper bounds to the predicted production or any other economic objective from history-matched reservoir models. The method consists of two steps: 1) performing a traditional computer-assisted history match of a reservoir model with the objective to minimize the mismatch between predicted and observed...

Identification of flow-relevant structural features in history matching

Identifiability of location and magnitude of flow barriers in slightly compressible flow

Classic identifiability analysis of flow barriers in incompressible single-phase flow reveals that it is not possible to identify the location and permeability of low-permeability barriers from production data (wellbore pressures and rates), and that only averaged reservoir properties in between wells can be identified. We extend the classic...

Quantification of the impact of ensemble size on the quality of an ensemble gradient using principles of hypothesis testing

With an increase in the number of applications of ensemble optimization (EnOpt) for production optimization, the theoretical understanding of the gradient quality has received little attention. An important factor that influences the quality of the gradient estimate is the number of samples. In this study we use principles from statistical...

The egg model - A geological ensemble for reservoir simulation

The ‘Egg Model’ is a synthetic reservoir model consisting of an ensemble of 101 relatively small three-dimensional realizations of a channelized oil reservoir produced under water flooding conditions with eight water injectors and four oil producers. It has been used in numerous publications to demonstrate a variety of aspects related to...

Hidden information in ill-posed inverse problems

It is well known that parameter updating of large-scale numerical reservoir flow models (a.k.a. ‘computer assisted history matching’) is an ill-posed inverse problem. Typically the number of uncertain parameters in a reservoir flow model is very large whereas the available information for estimating these parameters is limited. The classic...

The Egg model

The "Egg Model" is a synthetic reservoir model consisting of an ensemble of 101 relatively small three-dimensional realizations of a channelized reservoir produced under water flooding conditions with eight water injectors and four producers. It has been used in numerous publications to demonstrate a variety of aspects related to computer...