Recuperative Furnaces

In recuperative systems, incoming cold air is heated by a continuous flow of the exhaust gases using a heat exchanger. Recuperative burners are mainly used for fiber glass production (Worrell et al., 2008. p.62) or in smaller furnaces. Air preheat temperatures are limited to around 800°C for metallic recuperators, and the heat recovered by this system is thus lower than for the regenerative furnace. The lower direct energy efficiency may be compensated by additional heat recovery systems on the waste gases, either to preheat raw materials or for the production of steam (CII, undated, p.142). Recuperative furnaces, on the other hand, provide better temperature uniformity as they are free from temperature fluctuations in the checker of regenerative furnaces (Worrell et al., 2008. p.62) .

Development Status Products
Commercial
Glass, Fiber glass

Recuperative FurnacesCosts & Benefits

Parent Process: Melting and Refining
Energy Savings Potential

Energy savings up to 30% compared to cold-air furnaces (Worrell et al., 2008. p.62).

CO2 Emission Reduction Potential
Costs

Payback times are estimated between 7 to 14 months [based on a fuel cost of US $ 4.3/GJ] (Worrell et al., 2008. p.62)

Indian flag In an Indian plant a recuperation system was installed for Rs. 0.3 million, and provided savings of Rs. 0.88 million per year - resulting in a payback time of 5 months (CII, undated. p.144). 

Recuperative FurnacesSchematic

Recuperative Furnaces Publications

Page Number: 

62

Page Number: 

142-144