Air Compressor Heat Recovery Systems
Hot Air Utilisation
As self-contained complete systems, modern rotary screw compressors, oil free (dry compression) screw compressors, high pressure boosters and rotary blowers are especially well suited for heat recovery systems as all convert almost 100% of the electrical drive energy supplied to them into heat. The heat flow diagram (please see below) shows how this energy is distributed within the compressor system and how much of it is reusable. Approximately 96% of the energy input can be recovered for reuse, whilst 2% remains in the compressed air and another 2% is dissipated into the ambient surroundings.
In particular, direct usage of the recoverable heat via an exhaust air ducting system enables up to 96% of the total energy input to be recovered and reused as hot air for space or process heating purposes, simply and effectively providing heat to neighbouring spaces or to wherever it is needed free of charge. A ventilation flap in the ducting system allows the heated cooling air to be conveyed outside during summer operation or to the areas that require heating during winter operation.
To learn more about the huge savings that can be achieved using hot air heat recovery compared to fuel oil or natural gas, please refer to our Heat Recovery Systems brochure for further information.
Hot Water – Heating Service and Process Water
By reusing the exhaust heat from the compressor, booster or blower package, heat exchanger systems can recover up to 76% of the heat energy to provide heated water that can then be used in production, in your heating system or as service water on demand at temperatures up to +70°C, or even +90°C if required. For standard applications using heat recovery systems for the production of hot water and service water, PTG platetype heat exchangers are used. This significantly reduces the amount of primary energy required for heating purposes.
Special, fail-safe heat exchangers are used in the case of operations without an interconnected water circuit, or for applications with the highest demands of purity for the heated water, such as with cleaning water in the food industry.
PTG Plate Heat Exchanger System
KAESER rotary screw compressors from the SM Series (from 5.5 kW) upwards can be equipped with PTG systems. Depending on the size of the compressor system, the PTG heat exchanger is either integrated within the unit or is installed externally.
Fields of Application:
- Feeding central heating systems
- Laundry facilities
- General process heat
- Washing water in the food industry
- Swimming pool heating
- Hot water for showers and washrooms
Tube-type Heat Exchanger
In water-cooled systems, integrated plate or tube-type heat exchangers are available, depending on the available water quality. Our specialist engineers can advise you about which design is right for your particular application and requirements.
To learn more about the huge savings that can be achieved using water heating compared to fuel oil or natural gas, please refer to our Heat Recovery Systems brochure for further details and savings calculation examples.
In addition, with the KAESER Heat Recovery Calculator, you can interactively calculate the usable heating energy volume of a rotary screw compressor.