1-What are the various coal analysis are carried out in plant lab?
- Surface moisture
- Inherent moisture
- Total moisture
- Volatile matter
- Fixed carbon
- Unburned carbon
- Moisture in ash
- GCV by Bomb calorimeter & by calculation
- Sieve analysis
2-How do you calculate the surface moisture (SM) of coal?
Take 100 gram of coal sample whose size is < 12.5 mm & keep this sample in lab for 24 hours at atmospheric condition.
Then calculate the surface moisture = Loss in weight X 100 / Weight of the sample (100 gram)
For example: After drying the 100 gram coal in lab for 24 hours its total becomes 92 gram then,
Surface moisture = (100-92) X 100 / 100 = 8%
3- How do you calculate the Inherent moisture (IM) of coal?
After analysis of surface moisture, take 5 gram of coal sample & powder it to 212 microns or 0.212 mm & keep it in oven at temperature 108 deg C for 1 Hr
Sample is then cooled & is weighed & IM is calculated as
Inherent Moisture = = Loss in weight X 100 / Weight of the sample (5 gram)
4-What do you mean by Total moisture (TM) of coal? & how do you calculate the Total Moisture of coal?
Coal containing free visible & non visible water is called total moisture of coal. The total moisture of coal is due to rain or coal in contact with water.
TM is calculation:
Take 100 gram of coal sample of size < 12.5mm & keep it in oven for 1 hour at 108 deg C
Sample is then cooled & is weighed & TM is calculated as
Total Moisture = Loss in weight X 100 / Weight of the sample (100 gram)
Total moisture is the sum of IM & SM
5-How do you calculate Volatile matter present in coal?
Take 2 gram of moisture free coal sample & keep it in muffle furnace for 7 minutes at 900 deg C temperature. Then cool it in desiccator for 15 minutes. Then sample is again weighed for final weight.
Volatile matter = Loss in weight X 100 / Weight of the sample (2 gram)
6-How do you calculate the percentage of ash present in coal?
Take 1 gram of coal sample & keep it in muffle furnace for 1 Hr at 900 deg C temperature. Then cool it in desiccator for 15 minutes. Then sample is again weighed for final weight.
Ash % = Residual weight X 100 / Total weight of the sample (1 gram)
7-Write down the formula for calculating Fixed Carbon (FC)
Fixed carbon FC = 100-(TM+VM+Ash)
8-How do you calculate the unburned carbon in ash sample?
Take 1 gram of ash sample & burn it in muffle furnace for 1 hr at temperature 900 deg c. Then cool it in desiccator for 15 minutes. Then sample is again weighed for final weight.
% of unburned carbon = Loss in weight X 100 / Weight of the sample (1 gram)
9-How do you convert GCV of coal from Air dried basis (ADB) to As received basis (ARB) & Vice versa?
GCV ADB to ARB =GCVADB X (100-TM) / (100-IM)
GCV ARB to ADB =GCVARB X (100-IM) / (100-TM)
10-How do you convert coal GCV from ADB to Dried basis?
ADB to DB = GCVADB X 100 / (100-IM)
11-What are the two different types of coal analysis?
Proximate Analysis & Ultimate analysis
12-What parameters of coal are analysed in proximate analysis of coal?
Moisture, Volatile matter, Ash & Fixed carbon
13- What parameters of coal are analysed in Ultimate analysis of coal?
Total Carbon, Hydrogen, Nitrogen, Oxygen & Sulphur
14-How do you convert Higher Calorific value of coal into Lower calorific Value coal?
LCV = HCV - (9 X H2 X 586)
15-A coal sample of HCV 5100 kcal/kg having 3.5% of hydrogen in it, then calculate the LCV
LCV = HCV - (9 X H2 X 586) = 5100 – (9 X 3.5% X 586) = 4915.41 kcal/kg
16-A coal sample of GCV 4800 kcal/kg having total moisture 18%, then calculate the Net calorific value (NCV) of coal
NCV = GCV-(10.02 X Moisture) = 4800 – (10.02 X 18) = 4619.64 kcal/kg
OFIXO Multi-Purpose Laptop Table/Study Table/Bed Table/Foldable and Portable Wooden/Writing Desk (Wooden)BUY NOW