Search Results

Experimental Investigation and High Resolution Simulator of in-Situ Combustion Processes Quarterly Report

Description: Accurate simulation of in-situ combustion processes is computationally very challenging because the spatial and temporal scales over which the combustion process takes place are very small. In this fifth quarterly report of our DoE funded research, we continue the discussion of the design of a new simulation tool based on an efficient Cartesian Adaptive Mesh Refinement technique that allows much higher grid densities to be used near typical fronts than current simulators. We have now developed an appropriate upscaling technique for our grids, based on the local-global upscaling approach. We show preliminary results on two-dimensional test cases. On the experimental side, we continued experiments to measure the rates and kinetics of combustion in the presence and absence of metallic additives. In this quarter, we developed a better understanding of the cation replacing power of the various additives that affect combustion performance positively, and obtained a preliminary reactivity series. We also resumed our experimental investigation into the cyclic solvent-combustion process using crude oil from the Hamaca Region of Venezuela. Various measurements were made including oxygen consumption as a function of temperature. Preliminary results show that the temperatures for the onset of combustion are a function of the solvent injected.
Date: February 1, 2005
Creator: Gerritsen, Margot & Kovscek, Anthony R.

Experimental Investigation and High Resolution Simulator of in-Situ Combustion Processes Quarterly Report

Description: Accurate simulation of in-situ combustion processes is computationally very challenging because the spatial and temporal scales over which the combustion process takes place are very small. In this third quarterly report of our DoE funded research, we continue the discussion of the design of a new simulation tool based on an efficient Cartesian Adaptive Mesh Refinement technique that allows much higher grid densities to be used near typical fronts than current simulators. Also, we discuss the possibility of using Strang splitting for handling the large disparity in time-scales between the kinetics and transport in the in-situ combustion process. On the experimental side, we show results of experiments with our scanning electron microscope (SEM) to investigate the sand-clay-salt mixtures that are used for combustion in which we focus on grain sizes, shapes, orientations, characteristic inter-structures, and element analysis. SEM is shown to be a very effective tool in studying these mixtures.
Date: October 1, 2004
Creator: Gerritsen, Margot & Kovscek, Anthony R.

Experimental Investigation and High Resolution Simulator of in-Situ Combustion Processes Quarterly Report

Description: Accurate simulation of in-situ combustion processes is computationally very challenging because the spatial and temporal scales over which the combustion process takes place are very small. In this sixth quarter of our DoE funded research, we continued the development of our new simulation tool which is based on an efficient Cartesian Adaptive Mesh Refinement technique. This methodology allows much higher grid densities to be used near typical fronts than current simulators. We improved the upscaling strategy on these grids, and derived an effective way to generate upscaled permeabilities that preserve local fluxes. We have started more in-depth research into splitting methods for stiff PDEs such as those found in in-situ combustion simulation. We will report on these new developments extensively in the next quarterly report. This quarterly report, we focus on experimental work. On the experimental side, we have fleshed out a mechanism of improved in-situ combustion with aqueous metallic salts using scanning electron microscopy (SEM) and the transport phenomenon of such additives through porous media. Based on the observations from SEM analysis, we propose cation exchange of metallic salts with clay as a mechanism to create activated sites that enhance combustion reactions between oil and oxygen. Moreover, the empirical ranking of the success of metallic ions as catalytic additives for in-situ combustion is interpreted as originating from three factors: cation replacing power, distribution of metallic additive adsorption sites, and cation catalytic power for oxidation and cracking of hydrocarbon.
Date: April 1, 2005
Creator: Gerritsen, Margot & Kovscek, Anthony R.
Back to Top of Screen