Last month’s Technical Forum concluded with the following closing comments: “A sufficient supply of oxygen to the kiln is critical. Any limitations on the drawing of oxygen into the kiln or exhausting the gases from the kiln are also a common cause of such problems.” Therefore, this month’s Technical Forum considers the need for aspiration to help increase oxygen supply to the kiln and improve burning conditions.
Getting sufficient oxygen into the kiln is critical to maintain oxidising combustion conditions for the fuel burnt in the kiln. If insufficient oxygen is provided then the fuel is not burnt completely to carbon dioxide and water vapour, and its full calorific value is not released. In reducing burning conditions the volatility of sulphate in the kiln is increased and this can lead to problems of build-up in the preheater and ring formation in the kiln, as discussed in last month’s Technical Forum.
