Combustion gas flow modulation for ceramics - by periodic change between extreme values to give temp. adjustment in firing zone of tunnel kiln.

摘要

Modulation of mass flow of combustion gas to a discontinuously operated burner e.g. in a tunnel kiln for a ceramic industry comprises constantly changing flow mass of the combustion gas to the burner (3) periodically between two extreme values. This overlays the mean flow mass (M) with a time-based rising and/or falling tendency. The amplitude (A) and/or the amplitude density of the overlaid flow mass can be varied. Pref. (A) and/or the amplitude density of the overlaid flow mass is adjusted w.r.t. temp. distribution in the tunnel kiln (1) and/or the nature of the charge to be fired, to eliminate effect on the temp. distribution through the charge and/or the kiln capacity. The frequency of the overlaid flow mass modulation is higher than the passage frequency of the open temp. control circuit. The modulation frequency of the overlaid flow mass is equal to or a multiple of the monitoring frequency of the control circuit to establish the temp. ADVANTAGE - System is simple in operation, to adjust the temp. in the firing zone of the tunnel kiln w.r.t. various operating conditions.