A regenerative shaft kiln having at least two vertical shafts and a plurality of lances for introducing fuel into the kiln, with one or more sensor provided proximate a plurality of the lances, each of the sensors producing a first output signal having a magnitude and corresponding to a physical parameter...http://www.google.fr/patents/US6113387?utm_source=gb-gplus-shareBrevet US6113387 - Method and apparatus for controlling kiln
