ULTRAPYROLYSIS OF COLD LAKE BITUMEN

Abstract

Several pyrolysis experiments were conducted on a heavy oil (bitumen) feedstock to determine the product distributions which could be obtained using the Ultrapyrolysis process developed at the University of Western Ontario. Experiments were conducted at 650°C, at reaction residence times ranging from 133 to 448 ms. Solid residue formation of less than 8 wt% of the feed was observed. A condensible liquid was the major constituent of the product fractions. Its yield ranged from 58 to 73 wt% of the feed, decreasing at the longer reaction residence times. In addition, a non-condensible gas product fraction was formed. Its yield increased with reaction residence time from 17 to 34 wt% of the feed. The major gas components were C5-C6, ethylene, propylene, methane and butene-1. Formation of hydrogen sulphide gas amounted to less than 1 wt% of the feed. Experiments were also conducted at 100°C intervals between 550 and 850°C, at reaction residence times of around 145 ms. Solid residue formation of less than 10 wt% of the feed was observed over the complete temperature range studied. The total condensible liquid yield decreased with increasing temperature from 93 to 34 wt% of the feed. As the temperature was increased, the total gas yield increased from 3.5 to 50 wt% of the feed. There was a linear variation with temperature of the total liquid, total gas and solid residue yields. At higher temperatures, ethylene was the major gas component, with a yield of nearly 17 wt% of the feed. Preliminary analyses of the liquid products indicated reductions in viscosity, sulphur and nitrogen contents and nickel and vanadium contents. It was concluded that the Ultrapyrolysis process was effective in converting the bitumen feed into a favourable product distribution which included valuable chemical intermediates.