Hot Commissioning operations resumed at the Stuart Project in Queensland, Australia, in November.
Suncor, the operator, conducted 6 weeks of extensive studies, following a malfunction of the shale dryer that occurred on October 2, 1999. These studies involved additional technical experts from Suncor, Southern Pacific Petroleum/Central Pacific Minerals, Bechtel (the contractor) and other external parties.
The work during those 6 weeks confirmed that there was no serious physical damage to the plant during the recent malfunction. These studies resulted in a series of recommendations for the safe and effective resumption of operations. In line with these recommendations, Suncor made modifications to improve equipment reliability and implemented changes to commissioning and operational procedures. None of these changes required any material capital expenditure.
Commissioning recommenced on November 15, subsequent to the completion of the 6-week review program.
In this latest commissioning run, the plant was heated up and ran mainly on inert material for approximately 1 week, which permitted testing of various improvements to procedures and equipment. Shale was introduced on November 23, and after inert feed was displaced, shale feed was increased to 160 tonnes per hour, equivalent to 60 percent of capacity.
The run successfully demonstrated a number of improvements made during the detailed review process. These improvements included changes to the materials handling and dust collection system, and to the reliability and operability of the oil processing and recovery sections. The run extended for 30 hours with the plant operating within environmental parameters for nitrogen and sulfur oxides and particulates, except for one brief period when limits on particulates were exceeded. The amount of product produced demonstrated expected yields and both the raw naphtha and medium shale oil were close to specifications although further commissioning and operational running is required to confirm these results. The operator voluntarily ended the run after odor emissions were reported from the neighboring community, Targinnie, about 3 kilometers away.
Investigations into the cause and composition of air emissions have been intensified following this run. This work has involved the Queensland Department of Mines and Energy (DME), who implemented an Environmental Protection Order requiring certain clarifications and studies into air emissions, after the run. The operator is in the process of implementing those requirements that are necessary before recommencing commissioning. This includes a significant air emissions analysis program, which continued throughout the Christmas/New Year shut-down period. In addition, a longer-term work program into air emissions, characterization for the DME, has commenced.
The companies understand that the next run will be designed solely for the purpose of gathering more detailed data on plant air emissions. This will enable better identification of the source and nature of the emissions and allow adjustments to the process. This test program will be complemented by studies that will be undertaken off-site. Satisfactory analysis of emissions and, if necessary, any plan modifications will be completed before any further commissioning run is undertaken.
During and following the latest run, the operator worked closely with the Targinnie community on air emissions and dust issues. In addition to the work with the Targinnie community, the operator has also taken the opportunity to make some preplanned equipment modifications to improve environmental performance and to conduct maintenance programs.
While the companies say they are encouraged with the improved technical performance of the Stuart Stage 1 plant that was demonstrated in the latest run, they recognize that the emissions performance was not satisfactory. The need has been shown for additional work in a number of areas. While it is premature to predict the outcome of the current investigations and commissioning work, the companies are hopeful of the plant attaining reliable production around mid-2000. It will not be until the completion of the odor emission investigations, that the operator will develop a revised program for reliable oil production.