Regenerative Furnaces

Regenerative furnaces have two chambers, each containing refractory material, called the checker. While in one chamber the combustion gases pass through the checker and enter the furnace in the other chamber the checker is heated, or regenerated, with the outgoing hot exhaust gas. The furnace operates in two cycles, where about every 20 minutes, the flow is reversed so that the new combustion air can be heated by the checker. Typical air preheat temperatures (depending on the number of ports) are normally in the range of 1200 – 1350 ºC, sometimes up to º1400 C (IPTS/EC, 2012. p.47). Regenerative furnaces are very common in industry.

Side port (cross-fired) and end port configurations are the main types of regenerative furnaces. Side ports are most common and offer good flexibility for adjusting the furnace temperature profile.  End-port furnaces, on the other hand, are more energy efficient partly due to reduced heat losses through the ports and partly due to increased residence time of the combustion gases (IPTS/EC, 2012. p.48).

Multi-pass regenerators, the application of which will only be possible with the construction of a new furnace with the addition of more refractory bricks, recover the energy in the flue gases more efficiently, and can reduce the energy intensity of the furnace (Worrell et al., 2008. p.63).

Development Status Products
Commercial
Glass

Regenerative FurnacesCosts & Benefits

Parent Process: Melting and Refining
Energy Savings Potential

Regenerative furnaces can have thermal energy efficiency of up to 65% (US DOE, 2002. p.55)

Energy savings are correlated with the preheated combustion gas temperature. For example, with a combustion air temperature of 800 ºC gives energy saving of 35%.

Multi-pass regenerators can reduce the energy intensity of the furnace by 15% (Worrell et al., 2008. p.63).

CO2 Emission Reduction Potential
Costs

Regenerative FurnacesSchematic

Regenerative Furnaces Publications

Page Number: 

63

Page Number: 

46-48

Regenerative Furnaces Reference Documents

Best Available Techniques (BAT) Reference Document for the Manufacture of Glass

As a reference of the EU Industrial Emissions Directive (2010/75 EU) this new version provides extensive information on Best Available Techniques (BATs) applicable to European Glass Manufacturing Industry for reducing environmental impact. The document is prepared by the  Institute for the Prospective Technological Studies of European Commission's Joint Research Center. 

Page Number: 

47-49