Initial Operating Experiences and Overall Enhancements at the Chilean Coke Fired Petropower Cogeneration Facility

Abstract

On November 1, 1998 the Petropower Energia Limitada Project, located adjacent to Petrox’s 84,000 barrel per day (bpd) refinery in Talcahuano, Chile, entered into Commercial Operations. In addition to being the first public/private industrial partnership in Chile, it also was the first to combine petroleum coking technology with cogeneration technology in a single project financing. The project consists of a Delayed Coker Facility, which includes a 12,000 bpd Delayed Coker Unit and a 7,000 bpd Hydrotreating Unit, and a 74 MW (nominal, gross) Cogeneration Facility. The coke produced fuels a Foster Wheeler Circulating Fluidized Bed Boiler (CFB), and the energy produced provides electric power for the Petrox Refinery, the Delayed Coker Facility, and third parties, and high pressure steam for the refinery. The Cogeneration Facility, which consumes 24.8 Tonnes Per Hour of green coke, produces high-pressure steam, demineralized water and electricity for export to the refinery. The cogeneration unit also exports electricity, boiler feedwater and plant air to the Delayed Coker Facility. This leaves approximately 42 MW which is being exported to local third parties and the national grid. Environmentally, the overall project has resulted in a decrease in sulfur dioxide and particulate emissions from the refinery because of emission controls in the CFB, and elimination of burning fuel oil in the old utility system. Overall, the Delayed Coker Facility has permitted Petrox to refine heavier, less costly crudes, and the Hydrotreater Unit produces cleaner gasoline and diesel products. Petrox obtained these benefits without the expenditure of capital on the project, other than a small equity investment. The Cogeneration Facility has, and will continue to provide a long term, environmentally friendly solution to disposal of the high sulfur content coke produced by the coker, and maximizes its value as a high BTU (kilojoule - kJ) fuel for the Cogeneration Facility. The Cogeneration Facility has supplied all the refinery’s utility needs reliably and consistent with its expansion plans. After briefly describing the overall project, this paper places emphasis on the cogeneration plant with a focus on the operational experiences, including fouling, and the reliability improvements undertaken during the plant’s last three years of commercial operation. In addition, O&M costs and an overview of project economics are discussed.