Summary: | It has previously been shown that in situ upgrading of heavy oil by Toe-to-Heel Air Injection (THAI) can be augmented by surrounding the horizontal production well with an annulus of pelleted catalyst. Despite the further upgrading achieved with this configuration, the accumulation of coke and metals deposits on the catalyst and pore sites, resulting from cracking of the heavy oil, have a detrimental effect on the catalyst activity, life span and process. An alternative contacting pattern between the oil and transition metal dispersed catalysts was investigated using a stirred batch reactor, to mitigate the above mentioned challenges. The effects of different dispersed catalysts, hydrogen sources and tetralin hydrogen donor solvent were also investigated. The Taguchi method was applied to optimize the effect of reaction factors and select the optimum values that maximize level of heavy oil upgrading while suppressing coke yield. Detailed optimization of the reaction conditions for in situ catalytic upgrading of heavy oil was carried out over the following ranges of operating variables; temperature 355 – 425 \(^o\)C, reaction time 20 – 80 min, agitation 200 – 900 rpm, initial hydrogen pressure 10 – 50 bar, and iron metal loading 0.03 – 0.4 wt%.
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