Energy costs are significant for poultry processors. For example, one of Chile’s leading poultry processors relied on boilers to heat up to 350 gallons per minute of well water for their sanitation needs. At the same time, heat was being removed from the poultry being processed and discharged to the environment. As a result, the poultry processor was spending money to buy heat while spending money to waste heat. But, if they could capture the waste heat from processing, they might be able to use it to heat the water.

This poultry processor wanted the highest coefficient of performance (COP) possible and a technology solution with low annual operating and maintenance costs. The system needed to use a non-ozone depleting refrigerant with little global warming impact.

One of the few refrigerants that could meet all of their efficiency and environmental requirements was ammonia—an efficient refrigerant (designated as R-717) most commonly used by the food and beverage industry for process cooling and refrigeration. Ammonia does not contribute to ozone depletion or global warming, and can be used in a heat pump to reduce total energy demand.

Solution
The ammonia heat pump system delivers hot water for sanitation at 126°F using heat extracted from refrigeration, and features Vilter single screw compressors from Emerson Climate Technologies, Inc., Sidney, Ohio. With the new system, heat taken from their 14°F refrigeration load is lifted to 126°F in one stage for heating. Since commissioning in January 2012, the facility is heating 350 gallons of water per minute. And, the hot water is delivered far more efficiently than from their previous boiler. In fact, the ammonia heat pump solution has reduced heat energy cost by 72% and saved 15 million gallons of water per year. By using ammonia, Emerson’s compressor technology solution offers a refrigerant that has a good environmental profile (non-ozone depleting and zero global warming impact) and delivers higher temperatures. In addition, the balanced radial and axial force design of the single screw compressor reduces stress on the unit’s bearings, resulting in very low operating and maintenance costs, while delivering a performance unachievable with any other type of compressor.

Results
• 72% reduction of heat energy cost

• 15,000,000 gallons of water saved annually

• Waste heat recovery of 10.8 MMBtuh (3.2 MW)

• 5.9 coefficient of performance heat pump

• Non-ozone depleting refrigerant with zero global warming impact

• CO2 reduction of 3 million pounds per year

• Vilter single screw compressor with ammonia refrigerant achieves increased performance

• 15% higher efficiency than comparable technologies