A 20-year-old, Sofame direct-contact water heating system continues to deliver optimum performance for a Canadian Hospital.
Twenty years ago, when Sacré-Coeur Hospital in Montreal embarked on a more than $1 million project to upgrade its boiler plant, hospital officials made a bold decision to go with a Sofame direct-contact heat recovery system. At the time, this was relatively new technology. It was a smart decision.
According to Marcel Brabant, head of the hospital's maintenance operations, "Over the past two decades, I doubt if we have spent as much as $1,000 on repairs to the components of our direct-contact, heat recovery equipment."
Sacré-Coeur, a teaching hospital and health center associated with the University of Montreal, sits on a more than one million square feet. The main building dates back to 1925. A major upgrade to the boiler plant was required. The equipment was aging and becoming less efficient while spare parts for repairs were even harder to find. Because of the low-grade oil number 6, the oil heater had to be operated year-round, and pollution was a growing concern. For example, acid (SOx) droplets and soot deposits regularly fell on cars and neighboring houses.
To comply with Province of Quebec power plant regulations, constant supervision of the boiler premises had to be maintained 24 hours per day, requiring a heating plant crew of six boiler house operators.
The consulting engineering firm, Dessau-Soprin-represented by Laurier Nichols, engineer-was retained to work with hospital officials, particularly Brabant.
First, the team identified the specific objectives of the renovation project, placing top priority on:
- Reasonably quick return on investment (ROI)
- Reliability and optimum performance of new equipment purchases
- Minimal long-term maintenance costs
- Minimal equipment supervision costs
- Easy and efficient integration of new equipment into the old plant
- Lower SOx , NOx and CO2 releases into the environment
The key components of the system included a Sofame direct contact stack economizer that was installed on the two new steam boilers' flue gas exhausts and a 20,000,000-BTU/hour water heater to heat the building, replacing previously used steam. The system also included a plate-type heat exchanger for preheating DHW and a plate-type heat exchanger for makeup water. Several pumps were installed for functions that included:
- DHW preheating
- Makeup water for the boilers, air makeup and the laundry room
Twenty years later, Sacré-Coeur's boiler plant is still operating at peak efficiency. Brabant continues to be impressed with the sustainability of the equipment. As for his assessment of the annual savings resulting from the plant upgrade, Brabant points to these statistics:
- Energy: $170,000
- Supervision: $88,000
- Maintenance: $40,000
The ROI on the equipment was 4.5 years in annual savings.