Carbon footprint reduced largely by Ammonia system

Ammonia is one of the most efficient applications out there, with the application range from high to low temperatures. With the ever increasing focus on energy consumption, ammonia systems are a safe and sustainable choice for the future. Typically a flooded ammonia system would be 15-20 % more efficient than a  R404A counterpart.

The Ammonia System Helps Michigan Tech Reduce Carbon Footprint

Michigan Tech’s new ice-making system at the John J. MacInnes Student Ice Arena can make both ice and heat and reduce MichiganTechnologicalUniversity’s carbon footprint while doing so. The ammonia brine-based system not only makes ice for the hockey rink, it heats the rink’s sub-floor, preventing frost from forming under the insulated concrete slab. Heat generated as the ammonia is compressed to be used as a refrigerant heats 100 percent of the hot water used in the arena and maintains a comfortable water temperature for the nearby swimming pool and dive tank.

Michigan Tech replaced its ice-making system last summer, removing the building’s original Freon 22 direct system and installing an ammonia brine indirect system.

The reviews of the ice from rink users have been positive, but the most impressive part of the new system might be its reduced impact on the environment and the University’s budget.

“What you have is the most environmentally-friendly and energy-efficient system available,” said Mark Rodorigo, owner and CEO of Commercial Refrigeration of Virginia, Minn., which did the initial installation of the new system. “We replaced the Freon R-22, which is an ozone-depleting chemical, with anhydrous ammonia, an all-natural substance. Plus, we’re reclaiming the waste heat. You have reduced your carbon footprint tremendously.”

How does an ammonia system work?

A calcium chloride (saltwater) brine is chilled by the anhydrous ammonia refrigerant in a large shell and tube heat exchanger called the “chiller.” The brine leaves the chiller and is pumped through 13 miles of tubing inside the rink’s concrete slab. It leaves the mechanical room at 12 degrees Fahrenheit and returns a few degrees warmer back into the chiller.

Heat is created when the ammonia is compressed to be used as a refrigerant, producing a high-temperature gas that travels to three large water tanks that heat all the hot water used in the arena. The gas also feeds into a titanium-plated heat exchanger that heats the swimming pool and dive tank.

The last step in the ice-making process is the final cooling of the gas by an evaporative condenser. Because going through the water tanks and heat exchanger has already cooled the gas somewhat, the condenser requires less energy, water and chemicals, and this save the University thousands of dollars.

Early estimates put the annual savings at $40,000.

Anhydrous ammonia is a lot cheaper than R-22. And this system also helps saving money by using waste heat and reducing water and chemicals used in the evaporation condenser because less heat is emitted into the atmosphere.

This is a good example about how an ammonia system can help protecting the environment and save energy by reusing of waste heat.

Having emphasized on her responsibilities of protecting the environment, FOCUSUN has been focusing on promoting ammonia ice-making system and produces all kinds of ammonia ice-making systems. FOCUSUN also provides customers with professional tailored solutions to reduce energy consumption and trim budgets.

Source: http://www.mtu.edu/news/stories/2013/january/michigan-tech-ice-rink-goes-green.html