摘要 |
<p>This invention relates to a countercurrent combustion method and apparatus for the production of calcined lime in a furnace which contains, in sequence, at least one preheating zone, combustion zone, and a cooling zone. The entire combustion air is passed through the cooling zone thereby to preheat the same. A portion of the thus preheated air is withdrawn from the furnace and heated in a recuperation zone which may be within or outside the vertical shaft furnace but is located between the preheating zone and the combustion zone. In the recuperation zone, the air is heated to approximately the deacidification temperature and then is supplied to the combustion zone.</p> |