SaskPower captured 792,533 metric tons of CO2 in 2016 at its Boundary Dam power plant Unit 3 carbon capture and storage project, just 7,467 metric tons shy of its goal for the year. That total could be made up in three days of typical operation at the plant, according to Jonathan Tremblay, spokesman for the Saskatchewan, Canada, utility. “Throughout the year we had several unanticipated issues at the CCS [plant] that took us offline and that had an overall effect on our carbon dioxide capture totals,” Tremblay told GHG Weekly by email.
Still, the plant successfully captured 800,000 metric tons of C02 in the 12-month span from November 2015 to October 2016, proving the goal is feasible. The captured CO2 is sold to Canadian oil-producer Cenovus for use in enhanced oil recovery.
SaskPower released its year-end update Thursday, announcing the plant was operational 84.8 percent of 2016, just shy of the 85 percent goal. Coming into December, it appeared the facility would reach its targets, but Mother Nature intervened. “In December, we took the process down for cleaning. During that time, extreme winter conditions moved into the area and some of our water pipelines froze, which extended our maintenance period. This and other examples throughout the year have given SaskPower and the Boundary Dam operators important operational knowledge and experience on how the capture process best performs and reacts in different situations,” according to the update.
The necessary cleaning that required the system to shut down early in the month was not expected and hadn’t been completed during the last maintenance outage in November. “There is a cycle of cleaning operations for various sub-systems that we have developed – the whole plant is not cleaned every outage,” Tremblay explained.
During the unplanned shutdown temperatures plummeted to negative 4 degrees Fahrenheit, causing some wastewater pipes to freeze up and thus extending the shutdown by four days. “This should not have occurred and corrective steps have been initiated. However, the learnings involved included taking additional care with such piping infrastructure during the winter. The temperatures involved are quite typical and the system should have been able to handle it,” Tremblay said. SaskPower does not anticipate a repeat of the problem.
Moving forward, the plant will be cleaned every 8-12 weeks. “In the Spring/Summer of 2017 we are planning a significant outage to clean and inspect the process,” Tremblay said, adding that SaskPower hopes this maintenance will put the plant on a 12-week cleaning schedule.