Solvent Content Measurements of the Produced Stable Water-in-Oil Emulsions During Solvent-Aided Thermal Recovery Processes

The in situ solvent-aided thermal recovery processesare promisingmethods for recovering unconventional oil resources due to their higherefficiency, lower energy and water consumption, and reduced environmentalimpacts. The produced stream is often a highly stable water-in-oilemulsion, where the oil phase comprises bitumen and solvent. Separatingwater from such a sample is challenging because conventional approachesresult in solvent loss and sample contamination and render the solventcontent measurement techniques currently employed by the industryinvalid. Developing analytical techniques for solvent detection withoutsample dehydration, solvent loss, and contamination is essential forproduction surveillance, monitoring, process optimization, and economicevaluation. Solvent recovery and concentration measurement in producedstreams have been considered the most important issues associatedwith the success and commercialization of solvent-assisted recoveryprocesses. In this work, we implement a comprehensive chromatographictechnique to measure the solvent concentration of the actual bitumen/solvent/wateremulsions produced during a large 3D physical model experiment ofthe solvent-aided recovery process. We used combined gel permeationchromatography (GPC) and gas chromatography (GC) to obtain the fullcharacterization of bitumen/solvent/water systems. After characterizingfour produced emulsion samples, actual and synthetic multicomponentsolvents are used to establish the necessary calibrations for rapidand accurate determination of the organic solvent content in the producedemulsion samples. The results demonstrated that the automated GC/GPCcan be applied to actual minute amount emulsion samples for fast detectionof solvent content in the pilot and field-scale projects of solvent-aidedthermal recovery processes without sample dehydration while solventloss and sample contamination are entirely avoided.