Meat wholesaler dehumidifies to cut ice and cost

In South Africa, Durban’s moist and warm climate is an attraction for tourists but caused problems at Chester Wholesale Meat. The moist tropical air kept moving inwards from the truck loading area and condensing in the holding dispatch section, which is kept at 10°C. In addition to blinding mist, large amounts of condensation on the meat product, walls and floor caused a slippery build-up of water and provided a potential hazard for the workforce. This became so problematic that the area earned the nickname ‘the fish tank’.

The clean and dry 10°C holding area, previously nicknamed ‘The Fish Tank’ because of the condensation and mist.

Beyond the holding area, moist air made its way to the cold store, which, at -25°C, caused it to cool and flow downwards to the store floor. The result was considerable formation of frost on the freezer coils as well as the freezer entrance, walls, floors and on product. Not only was this energy-inefficient, requiring multiple defrost cycles per day and high refrigeration plant load, but the formation of frost was destructive to product packaging and to the Chester product itself.

For the client to be more efficient and successful, a moisture-free holding area and frost-free cold stores were needed.

Controlled climate - key to success

In order to alleviate the problem, Chester Wholesale Meat contacted Munters, with whom they had a four-year working partnership. Munters recommended the installation of IceDry MX2700 Desiccant dehumidifiers - one to be used in the holding area and one in the cold store.

Payback was immediate. By means of the dehumidification process, the IceDry application enabled Chester Wholesale Meat to reduce the refrigeration plant load 11 times more effectively by using the MX2700 units, rather than allowing the plant itself to dehumidify the air. This resulted in significant savings and an environmentally friendly reduction in power usage.Because of the insulation barrier formed by the build-up of ice in the past, refrigeration had had to run longer in order to obtain heat transfer through the ice. Defrosting was necessary on a more regular basis - which utilised more expensive energy.

Ice also caused forklifts to slip, resulting in repair to fridge panels, shelving and racking systems and damage to the forklifts themselves. The dangers of water or ice slippage and injury provided a significant occupational safety concern.

In addition, temperature fluctuations affected the longevity of the product. Frozen moisture in and on the product caused damage to product packaging, thus affecting product presentation.

Chester Wholesale Meat improved the safety and efficiency of its cold storage and holding area using Munters IceDry technology.

What does the dehumidifier do?

Munters IceDry application uses desiccant drying technology to absorb moisture from the air on a molecular level, using high-performance silica gel in a patented rotor technology. Because moisture is removed using the sorption process, the energy consumption is fractional. Typically the energy used for a Munters MX system to remove moisture is 11 times cheaper than for the ammonia plant to remove the same moisture at -25°C.

Range of dehumidification products

The MX2700 (2700 m³ of air/hour) unit used at Chester Wholesale Meat removes as much as 25 kg of water/hour in this cold environment, with an extremely small energy footprint. The MX2700 is the smallest of the MX range of units, ranging from 2700 to 9000 m³/hour. The MXs are the largest stand-alone dehumidifiers in the Munters range, while the MDU, Modular Dehumidification Units, process as much as 80,000 m³/hour.

Chester’s Operations Manager Steven Shrewsbury says that while he had had great expectations before the Munters system was installed, the impact of the system has actually exceeded his expectations.

He says the cleanliness of the plant now, with the absence of water and ice, is great for hygiene and provides a good working environment. Corrosion and maintenance costs have come down, which has had a positive effect on the attitude to housekeeping. The maintenance costs on forklifts in the plant have been reduced, while the shelf life of product and packaging in the freezers has increased.

Benefits of dehumidification at Chester Wholesale Meat

• Reduced energy consumption
• No frost and ice build-up at cold store entrances
• No or very few defrost cycles
• Dry floor in the holding area
• Prevention of ice build-up on coils
• Guaranteed meat product temperature and quality prior to transportation
• Improved staff and equipment safety (no slippery floors, no mist)
• Reduced refrigeration load up to 11 times