Good evening, hockey fans. Before we drop the puck for tonight’s game, let’s take a look at some numbers. The International Ice Hockey Federation (FIH, thanks to its French Canadian name of Fédération Internationale de Hockey) estimates there are 2,800 ice rinks in the U.S., of which 1,800 are indoor and therefore dependent on refrigeration (and not cold weather) for their ice. The FIH estimates that approximately 3,250 ice rinks are currently operational in Canada.
New ice rinks generally use ammonia as a refrigerant, but R-22 was the choice for many years, and the ice making systems in older rinks can contain several thousand pounds of R-22. In the approaching cold, hard reality of a post-R-22 world, how will rinks keep their ice cold and hard?
The U.S. Environmental Protection Agency (EPA) notes that change is on the horizon. Starting Jan. 1, 2020, U.S. production and import of HCFC-22 will end. However, this does not mean the use of R-22 must stop at that time.
“Since a significant inventory of virgin HCFC-22 exists, and recovered and reclaimed material will be available, the EPA expects use of HCFC-22 to continue well into the future,” the EPA said in a fact sheet on ice rinks.
However, planning for the future is still important.
The EPA noted that even though there is no immediate need for change, supply of HCFC-22 will decline over the next few years, and prices may rise. For existing HCFC-22 systems, this makes tightening leaks and performing preventive maintenance even more important to keep refrigerant emissions down and reduce the need to purchase additional HCFC-22.
When the time does come to replace or retrofit an existing system, the EPA has approved a number of alternatives that are safer for the environment for use both in new rinks and existing systems that require retrofit. For a full list of approved alternatives under the EPA’s Significant New Alternatives Policy (SNAP) program, visit http://bit.ly/SNAP-ICERINKS.
APPLYING CLIMATE-FRIENDLY TECHNOLOGIES
As ice rink operators and refrigeration contractors prepare for a post R-22 world, retrofits at R-22 rinks have been completed or are underway in a number of communities.
The Brooklyn Park Community Activity Center (CAC) in Brooklyn Park, Minnesota, is a city-operated recreational facility that is home to two 85-by-200-foot (regulation size) ice arenas. The rinks provide 6,700 hours of indoor ice time to approximately 100,000 patrons each year. The original arena, with a direct R-22 system, was constructed in 1983. The second arena, which uses an indirect ammonia/glycol system, was built in 1997.
The direct R-22 system consisted of two eight-cylinder reciprocating compressors, a low-pressure receiver, two pumper drums, an evaporative condenser, and a waste heat recovery system. The total heat extraction capacity of this system was approximately 136 ton (1.63 MMBtuh).
After 27 years of operation, the aging direct R-22 system began experiencing issues, such as corrosion in the vessels and rink floor piping. Eventually, three major leak events in the ice rink floor necessitated either significant repairs or replacement of the system.
In 2009, the City of Brooklyn Park began working with an engineering company to design an indirect ammonia/calcium chloride system to replace both rink refrigeration systems.
The new indirect ammonia/calcium chloride system has a refrigeration charge size of 387 pounds of NH3, which replaces the 6,000 pounds of R-22 and 1,200 pounds of NH3 used in the previous systems. Brooklyn Park expanded the ice equipment room in rink two to accommodate the NH3/CaCl2 system. The renovated equipment room now houses three compressors on concrete pads, an above-ground NH3 containment tank, a chiller, a leak-detection system, heat exchangers, and a combination of welded steel and high-density polyethylene piping.
According to the city of Brooklyn Park, the new system requires half the energy of the previous systems to perform at the same capacity. The incorporation of the heat pump system allows the recovery and reuse of 95 percent of the waste heat that is generated from the refrigeration system. The Brooklyn Park CAC ice rink is also achieving additional energy-efficiency gains due to the integration of a geothermal exchange system, which lowers the condensing temperature from a typical 96°F for NH3 to approximately 52–57°F, which resuls in increased operational efficiency.
The ice rink retrofit is one part of the city’s overall energy-efficiency project to reduce annual electric and natural gas consumption, a project that the city says is reducing emissions by more than 1.7 million pounds of CO2 equivalent annually. The ice arena upgrades account for nearly 30 percent of the project’s total carbon reductions.
HIGH-QUALITY ICE, LOW ENERGY CONSUMPTION
Another Minnesota arena, Bernick’s Arena in Sartell, recently completed a retrofit from R-22 to Honeywell’s Genetron Performax® LT (R-407F).
Built in 2003, Bernick’s Ice Arena recently completed a number of projects to make the building and its 30,000-square-foot arena floor more energy efficient. In the process, the decision was made to switch to a low-GWP (global warming potential) refrigerant product. Bernick’s and St. Cloud Refrigeration found an eager partner in Honeywell.
“It’s exciting to be among the first in the industry to switch to Performax LT,” said Jon Erickson, facilities manager at Bernick’s Ice Arena. “We need reliable products that produce high-quality ice and reduce our energy consumption. Ultimately, Performax LT will get us even closer to being the facility we want to be.”
According to Erickson, R-407F fit the requirements of the arena’s existing indirect refrigeration system and has staying power thanks to its listing under the EPA SNAP program.
“Since we wanted to retrofit our system instead of replace it, Performax LT was the perfect choice,” Erickson said. “It works very well and requires an amount of refrigerant similar to the R-22 we were already using.”
The retrofit was complete within a week, as planned. The contractor for the project, Mark Fitch of St. Cloud Refrigeration, doing business as SCR, said, “SCR enjoyed working with Honeywell, Bernick’s Arena, and Sartell Youth Hockey on this R-407F conversion. Now, Bernick’s Arena doesn’t have to worry about the R-22 phaseout and has a more environmentally friendly refrigerant in R-407F. Overall, I was impressed with how easily the system was installed and how smoothly the project ran while working with Honeywell.”
With the project complete, Bernick’s built up the ice to achieve a usable surface. The steps to building the arena floor included cooling it, flooding it, and allowing it to freeze; painting the base and lines; and then flooding it again. Bernick’s reported that with the R-407F, the floor only took six days to cool as opposed to seven with the R-22 system, and the rink only required half as many floods as it did with R-22.
The floor now cools faster, resulting in the water on top freezing faster. Previously, the floor temperature was set at 18°F to keep the ice at an ideal temperature for customers. Now, Bernick’s achieves the same results while keeping the floor set 3° degrees higher at 21°. This can mean the compressors don’t have to work as hard, which can lengthen their lives and contribute to energy savings.
“We definitely recommend other arenas make the change,” Erickson said. “The performance and energy savings are there, and we believe they will continue to be evident over time.”
Bernick’s added that choosing a retrofit over an entire system replacement saved more than $100,000, and those savings allowed them to make additional improvements to the facility.
Another EPA-approved option for ice rink operators is R-434a. R-434a is an R-22 replacement refrigerant that can be used in flooded, R-22 liquid overfeed ice rink systems without changing components or oil, according to ComStar Intl., which manufactures R-434a and markets it under the name RS-45. According to ComStar, RS-45 is a true drop-in replacement for R-22 as it blends with any remaining R-22 and has low glide.
“We’re proud to offer an affordable solution to ice rink managers who are stuck in a tough situation,” said Steve Mella, CEO, ComStar. He noted that the EPA’s 2020 ban on the new production and import of most R-22 will leave ice rink managers facing depleted supplies and rising costs. “Our RS-45 refrigerant has all the qualities to make a conversion seamless,” Mella said.
The Brownstown Sports Center in Brownstown Charter Township, Michigan, recently converted an R-22 rink to R-434a.
Brownstown Sports Center is a 40-year-old sports complex with two full-size ice sheets. The rink had a direct-liquid overfeed refrigeration system with approximately 11,000 pounds of R-22 operating with mineral oil. The system has two reciprocating compressors — a York Series G compressor and an Emerson Vilter 450 XL, a coalescing oil separator, and a manual expansion valve.
“I did a fair amount of research and concluded the easiest and least expensive fix was to change out the R-22 to ComStar’s RS-45 drop-in replacement refrigerant,” said Ron Zimmers, vice president of operations at the complex.
ComStar supplied the new R-434a along with empty cylinders for the R-22 that was removed from the system and subsequently purchased by ComStar. Serv-Ice Refrigeration of Northville, Michigan, evacuated the R-22 and recharged the system with R-434a for the two rinks over a four-day period in August. No maintenance was performed on the system before or during the replacement of refrigerant.
Zimmers monitored the sequence of events and said, “We charged the first ice sheet system with approximately 5,000 pounds of RS-45 and the ice was good to go the next morning. The results were much better than I imagined.”
The second ice sheet conversion began with no ice, just concrete. After observing the performance of the first sheet for two days, the crew charged the second rink with R-434a in the afternoon and flooded the rink with water during the night. The next morning the ice was solid, ready to be painted, and then re-flooded. Hockey players were skating on it the next day — a 36-hour turnaround.
“I’ve never seen ice freeze that fast,” Zimmers said. “The system actually runs more efficiently and smoother now.”
Mella added, “The Brownstown conversion to RS-45 proves that a sheet of ice can be changed out and become operational in 24 hours or less. We’re excited to make this happen for rinks all around the country.”
A similar R-434a conversion success story took place a few months later and 200 miles to the west at the Lakeshore Sports Centre in Muskegon, Michigan.
Lakeshore Sports Centre is a 41-year-old sports complex with two full-size ice sheets cooled by an overfeed ice rink refrigeration system containing approximately 10,000 pounds of R-22 operating with mineral oil. The compressor system, built in 1997, has two Vilter 440 reciprocating compressors with 75-horsepower belt-driven electric motors.
Following the discovery of a leak in one of the ice sheets, Sean Rekeny, manager, Lakeshore, conferred with the rinks’ decision-makers and determined they needed a second option to restore function rather than merely adding more R-22. After weighing the options, the Lakeshore team decided to convert to R-434a.
Initially, a full charge of R-22 was 5,000 pounds for each ice sheet. Lakeshore evacuated the R-22, transferred it to the other sheet, and recharged the sheet with 4,000 pounds of R-434a.
Rekeny said worries of problems associated with installing a different refrigerant other than R-22 proved to be unfounded.
“We had no detectable issues with oil return after a week of operating, which was our concern running mineral oil with a HFC blend,” he said. “In fact, the only modifications we did were adjusting a few liquid valves. Nothing else was needed. At the end of the day, we are very satisfied with the changeover and are excited for the future.”
“As a father of two hockey-playing sons, I am very pleased that we at ComStar can offer ice rinks an affordable and sustainable alternative to R-22,” Mella concluded.
Publication date: 2/6/2017
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