The economic and technical evaluation of heavy oil upgrading technologies has been the subject of many studies conducted by the Alberta Oil Sands Technology and Research Authority (AOSTRA). Based on the findings of these studies, major pilot plant demonstrations of four high conversion hydrogen addition processes, using Alberta feedstock, were undertaken by AOSTRA and the process developers.
This paper gives the results of a recent detailed study conducted by AOSTRA to compare the economics of one of these high conversion hydrogen addition processes, based on its test achievements, with the economics of upgrading processes representative of those currently in commercial use in Alberta.
In this study capital and operating cost estimates were developed for an upgrader complex, centrally located in Alberta, utilizing the following three alternative upgrading schemes:
Flexicoking with separate hydrotrealing.
Low conversion LC-Fining combined with delayed coking of unconverted bottoms and separate hydrotreating.
VEBA Combi-Cracker (VCC) - High conversion hydrogen addition with integrated hydrotreating.
Each scheme was designed to process 60,000 barrels per calendar day of Cold Lake bitumen and produce a synthetic crude oil that could be substituted for conventional crude oil.
With the capital and operating cost estimates as the base, detailed economic and sensitivity analyses were performed. The results of these analyses, as measured by the "Price Available for the Bitumen", indicated that high conversion hydrogen addition processes with integrated hydrotreating, such as VCC, offer a significant economic advantage over the currently employed coking processes combined with separate hydrotreating and over the low conversion hydrogen addition processes combined with separate hydrotreating and coking of unconverted bottoms. Technology does have an impact.
By far, the majority ot Canada's petroleum resources exist as heavy oil and bitumen. The development of these bitumen and heavy oil resources has the potential of playing a major role in supplying Canada's future energy demands.
The mandate of Alberta Oil Sands Technology and Research Authority (AOSTRA) is to support research and development which may promote development of these heavy oil and bitumen resources. One of the major areas of interest is upgrading, since the high cost of upgraders to partially refine or "upgrade" the heavy oil and bitumen has been one of the restrictions in Ihe development of these resources. Many extensive studies have been done in the past by AOSTRA to address the economics of upgrading heavy oil and bitumen. The most extensive and indepth study, "The AOSTRA Industry Upgrading Study (1983)", commissioned by AOSTRA and its industrial partners, had generally indicated that high conversion(>90%) hydrogen addition processes have a significant economic advantage over processes currently in use. The findings Of follow-up studies, done by AOSTRA, had further indicated that integration of hydrotreating with primary conversion further improved the economics of upgrading. These high conversion hydrocracking processes, however, have not been proven in commercial operation and therefore their use in a commercial venture represents a high technical and economic risk.
In order to accelerate the development and to demonstrate commercial viability of these high conversion technologies, AOSTRA, in conjunction with process developers undertook the following major demonstration programs: