Fishermen's News - The Advocate for the Commercial Fisherman

A Cold, Cold World


March 1, 2019

With the hatch system, pioneered by Seattle-based IMS Refrigeration/Wescold Systems, the top part of the unit sits on deck, while the bottom portion, which is in the fish hold, blasts the product with freezing cold air.

More and more when it comes to fish, consumers have additional concern about what they eat and where their food comes from. The trend toward healthier consumption has led to an increasing desire by harvesters for their fish to be as fresh as possible before heading to market and prior to consumption.

This need for better product has led to an evolution in the commercial fishing world, with one change being how fish are refrigerated after they're caught. This has led to advancements in the refrigeration industry that are still happening, insiders told Fishermen's News, as technology aims to keep pace with the needs of the industry and consumers.

One innovation that has expanded over the past year-and-a-half is the hatch-mounted blast system, a way of cooling the catch once it's stored aboard a vessel. With the hatch system, the top part of the unit sits on deck, while the bottom portion, which is in the fish hold, blasts the product with freezing cold air.

The innovation was pioneered by Seattle-based IMS Refrigeration/Wescold Systems, the company's operations director, Kurt Ness, said. The system's mobility is one of the keys to its increasing popularity, he said.

"At the end of the season, if that tuna boat is in a different market, say doing salmon or crab, you simply lift the hatch-mounted blast system off the deck, store it, and then you can go do your other fishery," Ness explained. "Say you have a refrigerated seawater system that circulates water inside that same fish hold, but you're doing Dungeness crab or salmon, for example. It's a way to get that blast frozen product and price without having a permanently mounted piece of equipment on your boat, it just kind of pops on and pops off."

"We also do that for refrigerated seawater systems, it's very common for larger tenders that say, might be doing king crab during part of the year and then they're doing tendering say in the summer, and we have deck mounted RSW (refrigerated sea water) systems where everything's in one footprint – the chillers, the condenser, the compressor; everything's on one skid, enclosed in a shroud. There's plumbing that comes to the unit, there's electrical that comes to the unit."

"So then that boat can essentially chill and be a tender in Bristol Bay and then at the end of the season, pop that unit off, store it and then have that deck space open for other equipment when they're going king crabbing, for example," Ness said.

He said that IMS has had the technology for years, but that it's becoming more popular as people see the appeal of having a smaller footprint piece of equipment that's not permanently mounted.

"I would say that the trend is not necessarily in new technology, it's just that more fisheries, more people are getting involved in the whole push for quality. And that quality starts with best handling practices, and with immediately refrigerating your catch," he said. "The industry in general is making a real concerted effort to have the highest quality product available, and with that comes a really robust, sturdy, dependable refrigerated seawater system, brine freezing system or blast freezing system."

Diesel-Driven RSW

In the past, it was usually hydraulically driven refrigerated seawater systems that led the commercial fishing industry, but things have changed, Ness said.

"We're seeing a big push towards diesel drive RSW (refrigerated sea water) systems," he remarked. "That's like a fully self-contained RSW system where you're not using the vessel's main engine, you have a dedicated power pack."

"We use a diesel engine and that drives the RSW system, so you're not having to run the main engine, there's no hydraulics involved; it's really more of a plug-and-play self-contained system that's become very popular in certain markets, specifically Bristol Bay," he explained.

Ness said that his company has had a diesel drive option for a number of years, and over the past year-and-a-half, IMS has developed an electric drive unit that's designed for the small boat market on Bristol Bay in Southwest Alaska.

"You can use a small nine- or 10-kw single phase generator to power the refrigerated seawater system," he explained. "With neither of those options are you using the main engine of the boat, so you can shut off your vessel and still chill seawater, still chill your salmon or whatever product you're delivering, and save on fuel consumption."

"It's a very efficient way of doing things," he continued. "It used to be 90 percent of the units were driven hydraulically, so we're seeing a real shift in focus in how to refrigerate fish."

The technology, he said, is driven by a trend in which more consumers want fish that's not highly processed.

"Less of the salmon's going in the can, more of it's being processed frozen or for the fresh market," Ness commented. "And in order to do that, you need a really high-quality fish. Fishermen are delivering a much better product when they're using refrigerated seawater systems."

Ness said the electric drive unit, which is specifically designed for boats that don't have the power to run the units hydraulically and is relatively new to the market, has been very successful so far.

"The main engine maybe doesn't have the capability to do so, and perhaps the boat is also too small to have a direct drive diesel-driven RSW unit," he explained. "So this is a much smaller footprint, small RSW package with a small single-phase generator."

The units, he said, are hitting a small boat segment that in the past would never have been able to put refrigerated systems on their vessel.

"I think it's helped open the market for a lot of people that otherwise wouldn't necessarily have had a market for their fish," he said.

Cutting Hydrofluorocarbons

There are other developing market trends, according to Wally McDonald, owner of southeast Alaska-based Fleet Refrigeration, some of which have to do with the phasing out of the refrigerant R-22 by the Environmental Protection Agency due to it being an ozone-depleting substance. Production and import of such refrigerants is being eliminated by the feds starting in 2020.

"As R-22 has been phased out, there's still a lot of R-22 equipment out there, but we've gone over primarily to a couple of other refrigerants – R-507 and R-404A – which are chemically about interchangeable," McDonald said.

There's been of a gradual transition to the use of the non-R-22 refrigerants, McDonald said, and it involves installing new equipment to handle the different refrigerant. But eventually, he said he expects R-507 and R-404A to be banned by the EPA as well.

"We'll go from HFC (hydrofluorocarbon) refrigerants to HFO alternative refrigerants," he said. HFOs, or hydrofluro-olefins, are a new class of refrigerants that have much less global warming potential than HFCs. They're not in widespread usage yet, partially because of the cost.

"The development of HFO will probably follow the course of where the current refrigerants will go up and the price of the replacement refrigerant will come down until we get to that critical point where it becomes financially feasible," McDonald predicted.

One advancement that Fleet Refrigeration has been working on, McDonald said, is designing reefer systems that can make more out of less.

"Basically, sizing the condenser so it'll hold an additional refrigerant charge without eliminating some of the other components," he explained. "We've designed more efficient systems that use a smaller charge."

The innovation, he said, was borne out of a financial necessity.

"When refrigerant was cheap, it was no big deal if a system took a couple hundred pounds of refrigerant," McDonald explained. "Well, that 200 pounds of refrigerant, if its R-22, you're talking several thousand dollars now, where it was a couple hundred before."

C02 Usage

At Seattle-based Highland Refrigeration, company President Lars Matthiesen, a mechanical engineer, told Fishermen's News that one of his company's biggest accomplishments in recent months is being the first to use carbon dioxide as a secondary refrigerant.

In the Highland system, a two-stage or an economized ammonia chiller is operated at -48F, with a chilled carbon dioxide (CO2) temperature of -40F. The CO2 liquid refrigerant is pumped out to the freezers where it is evaporated and returned to the chiller.

Over the past year-and-a-half, IMS has developed an electric drive unit that's designed for the small boat market on Bristol Bay.

"We do it without allowing any compression on the second side, so we save a lot of energy in part-load conditions, and so on," Matthiesen explained. "It's a simplified system that is mainly for very large systems for freezing 100-plus tons a day."

The company's first CO2-based RSW system on a US fishing vessel was installed on the F/V Northern Defender, in June 2018. It was designed and built in Seattle by Highland Refrigeration.

The system is capable of cooling 1,500 gpm of seawater down to 32ºF.

"We are the only ones that have come up with the solution so far," Matthiesen said, remarking that production is expected to ramp up this year.

"There will be new boats coming out in the next year or so," he said, "that will have that system onboard."


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