Applying technology and prefabrication “avoids damaging shutdowns” for natural refrigeration retrofits, according to case studies presented by Mark Stencel, Director of Refrigeration Product Solutions at industrial contractor Bassett Mechanical at the ATMOsphere America Summit 2023, held June 12–13 in Washington, D.C.
“Well-planned retrofits do not need to be disruptive or seen as gutting the entire infrastructure when upgrading systems to gain the benefits of sustainable, efficient natural refrigeration,” said Stencel, speaking about industrial retrofits with ammonia (R717) refrigeration and the emerging use of CO2 (R744) in industrial applications during a contractors panel discussion at the conference. ATMO America was organized by ATMOsphere, publisher of R744.com.
Kaukauna, Wisconsin (U.S.)-based Bassett Mechanical “simplifies” natural refrigeration installations and retrofits by using virtual design and construction for prefab production, linking field laser measurements with 3D design and computer numerically controlled (CNC) equipment processing.
For a retrofit, a laser scanner measures, within 0.25in (6.35mm) accuracy, the location and size of existing piping and equipment in a 30ft (9.1m) radius. Each scan takes roughly two minutes to complete. “In a short time, we can create a full 3D image of an engine room, installation or construction,” Stencel said.
With the pipes accurately measured, the operating components are separated, and the new design is formed using CNC processing.
Inside its 268,000ft2 (24,898m2) manufacturing/fabrication facility, Bassett Mechanical performs roughly 80% of project welds, giving the company the ability to prefabricate up to 40ft (12.2m) sections of pipe and equipment for just-in-time site location deliveries.
“It is a very structured, pre-determined, pre-planned approach, which in a retrofit or replacement simplifies the installation,” Stencel said.
No disruption at paper plant
In one case study presented by Stencel, a paper production facility wanted to remove two R22 chillers that used a water-cooled tower system, requiring “tremendous” amounts of water, he said. The R22 system was replaced with skidded CO2 chillers, using adiabatic condensing.
Benefits to the retrofit included a prefab solution that was not disruptive to the facility, with CO2 as a future-proof, efficient and cost-effective refrigerant, Stencel said. Voluntary carbon credits financially supported the industrial R22 system replacement, and the paper company realized “a measurable water conservation in the millions of gallons magnitude on an annual basis,” he added.
In another case study, a food production facility sought an ammonia system upgrade and asked Bassett to replace eight condensers over its Christmas shutdown. The ammonia system required new stainless-steel piping, so replacing the entire system in that time was “impossible,” according to Stencel.
Instead, Bassett used the laser scanner and CNC to develop a virtual design for a parallel system of pipes and large prefabricated sections. Over the Christmas shutdown, Bassett structurally put everything into place for the new system, installing the prefab components with the structural steel to enable replacing the condensers one at a time with the system running.
“People producing food products are every bit as sensitive as our supermarkets to avoiding shutdowns for any sort of time,” Stencel said. The company never incurred a long window of time without operating the system during the condenser replacements, he added.
“Well-planned retrofits do not need to be disruptive or seen as gutting the entire infrastructure when upgrading systems to gain the benefits of sustainable, efficient natural refrigeration.”Mark Stencel, Director of Refrigeration Product Solutions at Bassett Mechanical
A simple solution
Having worked in the natural refrigeration industry since 1989, Stencel chairs the International Institute of Ammonia Refrigeration (IIAR) Education Committee and is on the National Retail Federation Board. Part of his message at the summit was the need for the natural refrigeration industry to simplify solutions and to “intently listen to end users.”
“We have a simple and elegant solution to the carbon transmissions associated with refrigeration systems; that solution is natural refrigerants,” Stencel said.
“Those that are opposed to natural refrigeration will seize upon the perceived complexity,” he said. globalFACT, a nonprofit organization of synthetic refrigeration manufacturers, is a “well-financed group” spending advertising dollars to portray the message that CO2 and ammonia installations are too complex, disruptive and costly, he noted.
The natural refrigerants industry does not have the same advertising ability, according to Stencel. “What we have to do is stress the truth, use technology to simplify solutions and train and bring people forward, especially given that it is hard to tell much difference in complexity or jumble of components between natural refrigeration and synthetic systems.”
End users want to store and process food, not become refrigeration experts. “We, in the natural refrigeration industry, using our internal jargon contribute to the perception of complexity,” he added. Instead, “we need to get into the arena of where our customers live” by contributing to their understanding and providing straightforward, cost-effective natural refrigeration solutions.
Founded in 1936, Bassett Mechanical is an ISO certified, full-service refrigeration contractor offering design/build, installation, service, vessel/skid production, hygienic duct production and process safety management services.
The company is a third-generation mechanical contractor and metal fabricator with over 500 employees.
“We have a simple and elegant solution to the carbon transmissions associated with refrigeration systems; that solution is natural refrigerants.”Mark Stencel, Director of Refrigeration Product Solutions at Bassett Mechanical