Calculation of Energy Available from Flue Gases

Calculation of Energy Available from Flue Gases

Specific heat of exhaust gases / m³ for 800-900⁰C = 0.308 kcal/m³/c⁰

Temperature of exhaust gas available from the existing Rotary kiln    -    850⁰C

Temperature of exhaust gas after vertical drier                                   -    250⁰C

                                                                    -------------

Usable heat                                                            -      600⁰C

 Hence, heat available = 0.308 X 600⁰C

= 184.8 kcal.

Quantity of heat available per hour = 24,000 m³/hour

Total heat available = 184.8 X 24,000 = 4,435,200 kcal / hour

Capacity of Vertical drier = 20 tons per hour

Water evaporation per hour = 1,600 kgs (based on 8% moisture)

Energy needed per kg of water evaporation   -  625 kcal

Total heat spent on water evaporation  - 10,00,000 kcal/hour

Remaining heat available for pre-heating – 3,435,200 kcal/hour