Excess Air
In order to enable complete combustion in an actual process, the amount of oxygen has to exceed the theoretical level by a certain percentage. The amount of air that exceeds the theoretical amount is referred to as excess air. It is in fact impossible to predict an actual combustion and to estimate the excess air needed without measuring the products of the combustion. Excess air is not only important to ensure complete combustion, thereby ensuring that fuel is not wasted, but is also a key factor for safety reasons, for example to minimize the formation of hazardous gases like carbon monoxide (Cengel & Boles, 2006). Excess air and its extensive effects are discussed in greater detail in Section 3.1.3.