Wasted Heat In food and beverage processing, refrigeration absorbs heat from food products, machinery, personnel, the building envelope, ambient heat gains, and infiltration. Then the absorbed heat is typically rejected through condensers to ambient at temperatures ranging from 24°C to 35°C.
Simultaneously, 12.5°C water is heated to temperatures from 60°C up to 90°C or higher, through the burning and consumption of fossil fuels, for cleaning, scalding and cooking purposes. Since the inception of industrial refrigeration in the 1860's, processors have realised two opposing paths of energy across the boundaries of their facilities: refrigeration heat energy out, fossil fuel heat energy in.
A pressure-temperature relationship exists in refrigeration such that as pressure increases, temperature increases. With ammonia refrigeration, the extent of pressures and temperatures range from 0.35 bara/-50°C up to 13.4 bara/35°C. Generally accepted twin screw technology performs adequately within this range, yet inherent bearing load design limitations restrict the operation of twin screws outside of this range.
The fundamental design of Vilter single screw compressors is not limited to these pressures and temperatures. The internally balanced forces of the Vilter single screw allow it to operate at substantially higher pressures and higher differential pressures than twin screws. Vilter single screw compressors have been regularly used in a variety of high pressure applications including the compression of natural gas from 27.6 bara up to 56.7 bara, such as in landfill waste to energy projects, and are now being specified for use in industrial applications such as food and beverage processing and district heating.
Applied as industrial heat pumps, Vilter single screw compressors capture the heat absorbed by refrigeration and transfer the heat to water for beneficial heating duty, up to 90°C or higher. Single screw compressors renew the use of extracted heat energy from refrigeration, and offset the consumption of fossil fuels in the production of hot water.
Single screw industrial heat pump technology provides processors the ability to substantially reduce their overall operating costs and total cost of ownership. With simple paybacks from 1 to 3 years, users can reap huge financial benefits while contributing to the health of the planet as environmental stewards.
Refrigeration EaseVilter single screw compressors have been regularly applied in industrial refrigeration applications since 1990. The Vilter single screw is so technologically advanced that the same design attributes that enable its operation in high pressure heat pump applications are the same attributes that allow Vilter to offer this compressor with a 15-year bearing warranty when applied in the nearly effortless duty of refrigeration. Many Vilter single screw compressors are operating continously, well beyond 15 years, with their original bearings, saving substantial rebuild costs for their owners over the life of the compressors.