By recovering heat from the hot waste gas exiting a furnace and transferring it to the combustion air feeding the burners, fuel usage can be reduced by an average of twenty-five percent (25%), and in many cases, greater savings are realized. Waste gas temperatures entering convection recuperators are usually in the 1500°F to 2000°F range, and combustion air preheat temperatures are usually in the 800°F to 1200°F range.
For high temperature industrial furnaces, such as steel reheat furnaces, recuperators are valuable tools for increasing furnace efficiency. Up to sixty percent (60%) of the available energy in the fuel may be carried out of the furnace in the waste gas, therefore, heat recovery is essential for fuel conservation and economical operation. With fuel costs rising, recuperation is certain to play a vital role in the future.