Subject:- Applied Chemistry 2.

Topic:- Fuels.

Difficulty:- Medium

A sample of coal has following composition by mass C = 70 %, O = 8 %, H = 10 %, N = 3 %, S = 2%, Ash = 7 %. Calculate H.C.V. and L.C.V. using Dulong formula[Difficulty level-high]

Solution: HCV = 1/100[8080 C+34500(H-O/8) +2240 S] = 1/100[8080 + 70+34500(10-8/8) +2240 X 2] = 1/100 [565600 + 34500 (10-1) X 4480] = 1/100 [565600 + 310500 + 4480] = 1/100 [880580] = 8805.80kcal/kg LCV = [ HCV- 9/100 H X 587] kcal/kg = [8805.80-9/100 x 587] = [8805.80- 528.30] = 8277.80 kcal/kg Aswer: HCV/GCV = 8805.80kcal/kg
LCV/NCV = 8277.80 kcal/kg