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# How to Calculate Heat Loss Due to Incomplete Combustion?

Calculating percentage heat loss due to incomplete combustion to determine boiler efficiency.

## % Heat Loss Due to Partial Conversion of C to CO

Chemical products such as carbon monoxide and hydrogen and various hydrocarbons are usually present in the flue gas of the boilers. These products under incomplete combustion mix with oxygen present and burns again to release further energy. This causes certain loss which is one of the factors to determine the boiler loss. Below given the formula to calculate the loss occured due to incomplete combustion process.

Formula:
L5 = {(%CO x C) / (%CO + %CO2)} x (5744 / GCV of Fuel) x 100
Where,
L5 = % Heat loss due to partial conversion of C to CO
CO = Volume of CO in flue gas leaving economizer (%)
CO2 = Actual volume of CO2 in flue gas (%)
C = Carbon content kg / kg of fuel
GCV = Gross Calorific Value

Let us consider an example to calculate the percentage heat loss due to incomplete combustion of C to CO with the given values.
Step 1: Given that,
Volume of CO in flue gas leaving economizer (%) = 20
Actual volume of CO2 in flue gas (%) = 50
Carbon content kg / kg of fuel = 15
GCV of Fuel = 9000 kJ/kg

Step 2: Applying the values in the formula,
L5 = {(%CO x C) / (%CO + %CO2)} x (5744 / GCV of Fuel) x 100
L5 = {(20 x 15) / (20 + 50)} x (5744 / 9000) x 100
L5 = 273.52%

Result: % Heat Loss Due to Incomplete Combustion = 273.52%