Chemical Mass Balances

11. Combustion reactions:

A combustion reaction is a rapid reaction of oxygen with fuel or can be defined as: the sequence of exothermic chemical reactions between a fuel and an oxidant accompanied by the production of heat and conversion of chemical species for more information click this link http://en.wikipedia.org/wiki/Combustion_reaction

When fuel is burned, carbon in the fuel reacts to form either CO₂ or CO, hydrogen’s form H₂O and sulfur form SO₂.

If CO is formed the combustion reaction is referred to as a partial combustion

Examples:

C + CO₂  CO₂ (Complete combustion of carbon)

C₃H₈ + O₂  3O + 4H₂O (Partial Combustion of propane) 

In these kind of calculations we accept the composition to 79% N₂, 21% O 79 moles N₂/21 moles O₂ = 3.76 moles N₂/mole O₂.

A composition on wet basis is a term used to denote the component mole fraction of a gas that contains water. The product gas that leaves the furnace is referred to as stack gas or flue gas. http://en.wikipedia.org/wiki/Flue-gas_stack (more about flue gas)

Composition on wet and dry bases can be calculated

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