摘要 |
<p>A combination coal- crushing/drying and coal-firing process in which the volume of primary air is minimised, wherein the proportion of mill exhaust air laden with coal dust and not required as primary air is used for heating the secondary air and/or cooling the hot material. Preferably the process is used for the burning or roasting of cement clinker, lime or expanded clay using a rotary-kiln system having connected at the outlet side a planetary cooler, tubular cooler, shaft cooler or fluidised-bed cooler.</p> |