Engineering Tomorrow makes CO2 the right choice for cranberry processing plant

Tuesday, August 6, 2019

Established in 1996, Canneberges Bécancour is one of the most productive cranberry farms in North America. The farm is located on 450 acres in the Bois Franc region of Quebec, Canada—between Montreal and Quebec City, and, with 80 cranberry bogs, processes about a half-million pounds of cranberries per day during a typical harvest lasting four to six weeks in late fall.

Bob Hampson, one of Canneberges Bécancour’s founding partners, ventured into cranberry farming after selling his cold storage business. Hampson’s family owned Merchant’s Cold Storage in Providence, Rhode Island, and—in what would eventually help to make Hampson so willing to try new things and explore new technologies—were the first to purchase a screw compressor in the United States, install a Frick RWB2 compressor in their facility’s machine room, and utilize an air-supported structure for the chilled storage area of their New Bedford, Massachusetts cold storage facility.

Even though Hampson sold the cranberry business in 2009, Canneberges Bécancour—knowing Hampson’s expertise in both cranberry farming and cold storage—called on him about six years later for help developing a freezing facility that would support and complement the original 17,000-square-foot processing plant.

“Once harvested, cranberries need to be delivered over significant distances in a short time frame,” said Hampson. “Unfrozen cranberries that face long transit times can pose serious challenges and risks to the distributors.”

“If the berries could be frozen at the site of harvest before they are shipped across North America, the logistics become much more manageable and the risk is significantly reduced,” Hampson explained.

Working together with Canneberges Bécancour’s general manager Luc Decubber, Hampson began to decide on what type of refrigeration system the new freezing facility would require to ensure the system’s reliability and also offer positive energy efficiency and environmental benefits.


New freezing facility looks to natural refrigerants

They knew they needed to develop a refrigeration system that considered three things:

  1. The system could not use halocarbons.“We did not feel as though halocarbons were a good choice for the environment or atmosphere,” said Hampson. “Plus, practically speaking, given the global political pressure to eliminate them, it didn’t make good business sense to use them in this new facility.”
  2. The system needed to use CO2 instead of ammonia.“Although ammonia has a good track record in the industry and is a more environmentally-friendly and efficient option, a refrigerant leak could ruin an entire crop of cranberries—which could be as much as 25 million pounds at its peak. Additionally, the town fathers were averse to the construction of a large traditional ammonia facility,” he explained.
  3. The system needed to be able to be run without skilled refrigeration operators. “Initially, we investigated the possibility of using an ammonia/ CO2 system,” Hampson said, “but, in addition to the local restrictions, we found it to be too complex for how we wanted to operate the facility. So, when Luc and I found Carnot Refrigeration, we were pleased to learn they had already constructed two other industrial facilities using CO2 refrigeration systems in Quebec and had good experience with the type of system we were looking to use.”


Based in nearby Trois Rivieres, Quebec, Carnot Refrigeration has deep roots in the food retail industry, but has also broadened its expertise into data center cooling and, most recently, small industrial refrigeration facilities.

The system requirements for the new plant at Canneberges Bécancour included:

  • 100 percent CO2 refrigeration
  • 400 tons of refrigeration (TR), primarily freezers
  • Maximum energy efficiency, including minimal time in supercritical mode and maximized heat recovery
  • Fully automated controls

Plus, the facility needed to be completed within six months.


CO2 provides optimum efficiency

Ultimately, with Carnot’s guidance, the team decided on a CO2 refrigeration system that would be operated in subcritical mode on most cooling days and in the supercritical mode only when necessary. The system design also would enable heat recovery for underfloor heating, space heating, and process water.

Read the full case study here