| In order to increase heavy oil recovery many methods of in situ upgrading of heavy oil are being investigated around the world. These methods include physical separations (steam distillation or de-asphalting), underground thermal cracking or hydro-cracking, cold cracking, etc. There is a need for substantial heat energy in steam distillation and underground thermal cracking or hydro-cracking (at least 300°C). However, cold cracking (between room temperature to around 80°C) requires less energy while producing the same results. In recent years, much research has been conducted on in situ cold cracking of heavy oil in oil reservoirs.;These laboratory experiments indicate that upgrading of bitumen did occur in the emulsion experiment. Also, electrochemical reactions occurred in the sand pack experiment, but the radicals generated after the cleavage of macromolecular hydrocarbon appear to trigger further polymerization reaction. Thus, in the sand pack experiment, the viscosity of after-experiment oil is higher than that of the original bitumen. In addition, as expected, the organic acids were reduced to hydrocarbon. This would benefit the oil production equipment and the downstream refining equipment because the acidity of the oil is decreased.;The current research investigates in situ upgrading of bitumen in oil reservoirs using DC electricity (cold cracking). Heavy crude oil properties were measured using conventional techniques. Experiments were performed during which DC electricity was applied to emulsion (bitumen and brine emulsion) and artificial oil sand (made of brine, bitumen, and sand) using different voltages and water-cut. After the experiments, changes in properties of oil were observed and compared with those of the original bitumen. Understanding the effect of the laboratory experiments will help predict and explain the effects of on-site large scale experiments. |
