Oil-foam interactions in a micromodel

This report presents results of a pore-level visualization study of foam stability in the presence of oil. Many laboratory investigations have been carried out in the absence of oil, but comparatively few have been carried out in the presence of oil. For a field application, where the residual oil saturation may vary from as low as 0 to as high as 40% depending on the recovery method applied, any effect of the oil on foam stability becomes a crucial matter. Sandstone patterns were used in this study. The micromodels used are two-dimensional replicas of the flow path of Berea sandstone etched on to a silicon wafer to a prescribed depth, adapting fabrication techniques from the computer chip industry. After flooding the models up to connate water and residual oil saturations, surfactant flood followed by gas injection to generate foam was done. Visual observations were made using a high resolution microscope and pictures were recorded on videotape before being processed as they appear in this report

Heavy and Thermal Oil Recovery Production Mechanisms Progress Report

The Stanford University Petroleum Research Institute (SUPRI-A) conducts a broad spectrum of research intended to help improve the recovery efficiency from difficult to produce reservoirs including heavy oil and fractured low permeability systems. Our scope of work is relevant across near-, mid-, and long-term time frames. The primary functions of the group are to conduct direction-setting research, transfer research results to industry, and educate and train students for careers in industry. Presently, research in SUPRI-A is divided into 5 main project areas. These projects and their goals include: (1) Multiphase flow and rock properties--to develop better understanding of the physics of displacement in porous media through experiment and theory. This category includes work on imbibition, flow in fractured media, and the effect of temperature on relative permeability and capillary pressure. (2) Hot fluid injection--to improve the application of nonconventional wells for enhanced oil recovery and elucidate the mechanisms of steamdrive in low permeability, fractured porous media. (3) Mechanisms of primary heavy oil recovery--to develop a mechanistic understanding of so-called ''foamy oil'' and its associated physical chemistry. (4) In-situ combustion--to evaluate the effect of different reservoir parameters on the insitu combustion process. (5) Reservoir definition--to develop and improve techniques for evaluating formation properties from production information. What follows is a report on activities for the past year. Significant progress was made in all areas

Kinetics Oxidation of Heavy Oil. 2. Application of Genetic Algorithm for Evaluation of Kinetic Parameters

In-situ combustion (ISC) is the process of injecting air into oil reservoirs to oxidize part of the crude-oil and has been utilized for both light and heavy oil. The viscosity of the remaining crude-oil is reduced by the significant heat generated from combustion reactions, that contributes to enhanced oil recovery. In [give citation full out], we developed a new method to interpret Ramped Temperature Oxidation (RTO) experiments using a reactor model based on a compositional and full equation of state approach. In this work, we use this RTO reactor model coupled with an optimization tool in order to determine the optimal kinetic parameters for an extra heavy oil reservoir. Kinetic parameters are commonly determined using analytical methods and limited data. Typically only one type of observational data, for example oxygen consumption, is used from one experiment. Here, we use two series of experiments data, namely CO2 and O2 concentrations and a multi objective approach to obtain kinetic parameters for the different combustion reactions. We obtain finally a set of possible kinetic schemes, accouting for all mechanisms like reactions, phase changes and transport processes

Techno-economic and risk evaluation of a thermal recovery project

Field production data were studied, to derive an overall energy balance for the steamflood, to calculate the steamflood capture efficiency and predict future steamflood performance. Heat-losses due to produced fluids were also calculated. Predicted production schedules from the model were history-matched with field production data The reservoir parameters (porosity, {phi}, net thickness, h{sub n}, initial oil saturation, S{sub oi}, and residual oil saturation, S{sub or}) were evaluated statistically using both Gaussian and triangular distributions. These resulted in distributed recovery predictions. The Gaussian distributions behaved as predicted; but of great importance, the skewed triangular distributions also behaved in much the same manner. The results fit closely with predictions using logical formulas to predict expected values, peak values and standard variations of recoveries. This result is important, for it indicates that complete Monte-Carlo simulations may not be necessary. All steamflood calculations were carried out using a PC-based spreadsheet program. The major results were as follows: The capture efficiency of the Wilmington steamflood was calculated at 60%. This is an acceptable value, taking into account the reservoir geometry and history. The calculated heat balance showed high heat-loss to adjacent formations and through produced fluids. Of the cumulative heat injected at the time of the study, 21% had been lost to vertical conduction and 21% through produced fluids. Predicted production schedules indicated that up to 43% of the oil in place (at steamflood initiation) could be recovered by the steamflood

CT imaging techniques for two-phase and three-phase in-situ saturation measurements

The aim of this research is to use the SUPRI 3D steam injection laboratory model to establish a reliable method for 3-phase in-situ saturation measurements, and thereafter investigate the mechanism of steamflood at residual oil saturation. Demiral et al. designed and constructed a three dimensional laboratory model that can be used to measure temperature, pressure and heat loss data. The model is also designed so that its construction materials are not a limiting factor for CT scanning. We have used this model for our study. In this study, we saturated the model with mineral oil, and carried out waterflood until residual oil saturation. Steamflood was then carried out. A leak appeared at the bottom of the model. Despite this problem, the saturation results, obtained by using 2-phase and 3-phase saturation equations and obtained from the Cat scanner, were compared with the saturations obtained from material balance. The errors thus obtained were compared with those obtained by an error analysis carried out on the saturation equations. This report gives details of the experimental procedures, the data acquisition and data processing computer programs, and the analysis of a steamflood experiment carried out at residual oil saturation

Risks management and cobots. Identifying critical variables

Trabajo presentado en: 29th European Safety and Reliability Conference (ESREL), 22–26 September 2019, HannoverA collaborative robot or a "Cobot" is the name of a robot that can share a workspace with operators in the absence of a protective fence or with only partial protection. They represent a new and expanding sector of industrial robotics. This investigation draws from the latest international rules and safety parameters related to work with collaborative robots. Its detailed research is motivated by the design of a collaborative industrial robot system, hazard elimination, risk reduction, and different collaborative operations, such as power and force limiting, collaborative operation design, and end-effector safety requirements, among others. The purpose of our study is to analyze the most important variables that must be controlled in accordance with the desired use of the Cobot, according to ISO / TS 15066, ISO / TR 20218-1and some other generic safety regulations on machines and industrial robots. A series of observations and appreciations on the use of the Cobot will also be presented

CT measurements of two-phase flow in fractured porous media

The simulation of flow in naturally fractured reservoirs commonly divides the reservoir into two continua - the matrix system and the fracture system. Flow equations are written presuming that the primary flow between grid blocks occurs through the fracture system and that the primary fluid storage is in the matrix system. The dual porosity formulation of the equations assumes that there is no flow between matrix blocks while the dual permeability formulation allows fluid movement between matrix blocks. Since most of the fluid storage is contained in the matrix, recovery is dominated by the transfer of fluid from the matrix to the high conductivity fractures. The physical mechanisms influencing this transfer have been evaluated primarily through numerical studies. Relatively few experimental studies have investigated the transfer mechanisms. Early studies focused on the prediction of reservoir recoveries from the results of scaled experiments on single reservoir blocks. Recent experiments have investigated some of the mechanisms that are dominant in gravity drainage situations and in small block imbibition displacements. The mechanisms active in multiphase flow in fractured media need to be further illuminated, since some of the experimental results appear to be contradictory. This report describes the design, construction, and preliminary results of an experiment that studies imbibition displacement in two fracture blocks. Multiphase (oil/water) displacements will be conducted at the same rate on three core configurations. The configurations are a compact core, a two-block system with a 1 mm spacer between the blocks, and a two-block system with no spacer. The blocks are sealed in epoxy so that saturation measurements can be made throughout the displacement experiments using a Computed Tomography (CT) scanner

A degradation test plan for a non-homogeneous gamma process

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An adaptive condition-based maintenance planning approach: An offshore wind turbine case study

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