摘要 |
<p>A process for the calcining of limestone or hydrated lime by thermal treatment thereof with hot gases in an oxidizing atmosphere in a rotary kiln through which the kiln atmosphere and the charge are countercurrently passed, which kiln is fed with fuel from shell burners, is described. The invention resides in the use of different fuels which release different quantities of SO2 and SO3 per unit of calorific heat. The fuel which releases the larger quantity of SO2 or SO3 per unit value of calorific heat is supplied to the upper portion of the rotary kiln, and the fuel which releases the smaller quantity of SO2 and SO3 per unit of calorific heat is supplied to the lower portion of the rotary kiln.</p> |