Experimental study of high liquid viscosity oil-gas flows using ect and gamma radiation methods

Electrical capacitance tomography (ECT) and gamma ray densitometry have found applications in multiphase flows as both have been used to visualize flow patterns in the process, nuclear, chemical and oil-gas industries. However, liquid viscosity is often limited to about 10 cP in most of these applications. This study evaluates the suitability of ECT in the monitoring of multiphase flow consisting of heavy-oil (up to 7500 cP) and gas. Heavy-oil is of interest because of its huge reserves, increasing world energy demand, dwindling conventional-oil reserves, etc. The results obtained showed that ECT performed well in flow visualization and measurement of high-viscous oil/gas flows. Flow patterns identified included plug, slug, pseudo-slug (blow-through-slug) and annular flows. Liquid holdup measurements were found to be within ±10% and ±5% error in the static stratified and static annular test, respectively, based on the LBP algorithm while in dynamic test, it was considerably dependent on flow patterns and the LBP. Comparatively, high definition video recordings, pictures and gamma rays densitometer were used to validate the flow patterns identified by ECT.