Energy consumption and CO2 content in the flue gas of normal shaft kilns | Part 1: Influence of the air excess number
Balances were used to determine the effect of the contents of CaCO3, MgCO3, water and inert matter in limestone, the air excess number, the kiln wall losses and the residual CO2 content on energy consumption and CO2 content in the flue gas.
1 Introduction
The so-called multi-fuel-fired normal shaft kiln (NSK) is one of the oldest types of lime shaft kiln, in which burnt lime is produced from limestone by expelling the carbon dioxide gas. This type of kiln is fired with lumpy solid fuels. Due to this mode of firing, operation of the kiln has special characteristics that result in complex process technology. This kiln type is used in the lime industry in order to manufacture so-called medium to hard-burnt lime. It is also the main type of kiln to be found in the sugar and soda industries, only with the difference that two products...
