US 9,809,495 B2
Method for the closed-cell expansion of mineral material
Ernst Erwin Brunnmair, A-Graz (AT)
Assigned to BINDER + CO AG, Gleisdorf (AT)
Appl. No. 14/349,984
Filed by Binder + Co AG, Gleisdorf (AT)
PCT Filed Oct. 4, 2012, PCT No. PCT/EP2012/069653
§ 371(c)(1), (2) Date Apr. 4, 2014,
PCT Pub. No. WO2013/053635, PCT Pub. Date Apr. 18, 2013.
Claims priority of application No. 555/2011 U (AT), filed on Oct. 10, 2011.
Prior Publication US 2014/0291582 A1, Oct. 2, 2014
Int. Cl. F27B 1/22 (2006.01); C04B 20/06 (2006.01); C04B 38/00 (2006.01); F27B 1/00 (2006.01); F27B 1/14 (2006.01); F27B 1/24 (2006.01); F27B 1/26 (2006.01)
CPC C04B 20/066 (2013.01) [C04B 20/068 (2013.01); C04B 38/009 (2013.01); F27B 1/00 (2013.01); F27B 1/14 (2013.01); F27B 1/22 (2013.01); F27B 1/24 (2013.01); F27B 1/26 (2013.01)] 33 Claims
OG exemplary drawing
 
1. A method for producing an expanded granulate from a sand grain-shaped mineral material comprising a propellant, the method comprising:
feeding the sand grain-shaped mineral material-into a vertically upright furnace from above such that said sand grain-shaped mineral material falls along a drop section through multiple heating zones separated vertically from each other in a furnace shaft of the vertically upright furnace, wherein each of the multiple heating zones is outfitted with at least one independently controllable heating element;
heating the sand grain-shaped mineral material to a critical temperature at which surfaces of sand grains plasticize and the sand grains are expanded by the propellant in an isenthalpic manner, thereby forming an expanded sand grain-shaped mineral material; and
discharging the expanded sand grain-shaped mineral material at a bottom end of the vertically upright furnace, wherein upon detection of a first reduction in a temperature of the sand grain-shaped mineral material between two successive positions along the drop section, the at least one independently controllable heating element is controlled in the drop section after the two successive positions depending on the critical temperature.