Heat Recovery Systems
Heat Recovery Systems can provide significant energy and cost savings as well as environmental benefits.
Heat recovery systems are used to recover heat energy that would otherwise be lost, and use it for plant heating. For example, consider a 3500 kW power supply and two 4 metric ton furnaces with a total of 1,251 kW (4,266,250 BTU/hr) of heat rejection. Fuel oil has a heat content of 139,000 BTU’s per gallon. In one hour the heat rejection is equivalent to 30.5 gallons of fuel oil.
Heat recovery is typically accomplished with either an air handler or a heat exchanger.
Heat Recovery with an Air Handler
Similar to dry air coolers, air handlers have finned radiator coils with a fan to direct airflow through the tube bank. The air flow is contained inside ductwork and can be directed inside the building for heating and air make up during the winter, or directed outside the building for heat rejection in the summer. The unit can still be used for air make up in the summer by diverting the water flow to an external cooler outside the building.
| Heat Recovery System with Air Handler |
|---|
| No water consumption, or discharge |
| Low maintenance |
| Also functions as building air makeup |
| Closed loop system maintains clean water |
| Standard copper coils are suitable for use with de-ionized water |
Heat Recovery with a Heat Exchanger
Water to water heat exchangers can also be used for heat recovery applications. In this case, the heat exchanger is used to warm a secondary fluid for use in radiant heating systems.
| Heat Recovery System with Heat Exchanger |
|---|
| Can be readily added to most existing systems |
| Low maintenance |
| Closed loop system maintains clean water |
| Standard stainless steel plates are suitable for use with de-ionized water |
| Expandable for future increased capacity |
Options
| Heat Recovery System with Air Handler |
|---|
| Air intake filters to keep coil clean and to clean makeup air supply |
| May be coupled with a trim cooler for additional thermal capacity |
| Floor or ceiling mounting options |
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