| 摘要 |
<p>A tunnel kiln comprising pre-heating, furnace and cooling zones (12 min , 14 min , 16 min ). Exhaust gases from the furnace zone are vented by vents (30a,30b) from regions at or adjacent the upstream and downstream ends of the furnace zone (14 min ). The heat from the vented exhaust gases is recuperated and applied to the kiln burner system (34,39) as preheated combustion air. Unlike conventional kiln practice, there is no depressurisation of the upstream end of the pre-heating zone (12 min ) to promote a flow of exhaust gases counter to the direction of passage of a payload through the kiln.</p> |
