Coal handling plant (CHP) consists of ;
Inorder to calculate the coal handling and coal storage bunkercapacity, first we need to know the coal requireent per day for a plant, coal handling maintenance stratergy We shall calculate the coal handling & bunker capacity by taking an example of 25 MW thermal power plant consuming coal of GCV 4900 kcal/kg & having heat rate 3200 kcal/kwh running at 100% PLF. Plant running load = 50 MW X 100/100 = 25 MW We know that coal consumed = Heat rate X Power generation / (Coal GCV) Coal consumed =3200 X 25 / 4900 = 16.32 MT/hour Coal consumed in a day = 16.32 X 24 =391.68 MT take round figure 392 MT/day A-Coal handling capacity calculation Consderations:
Note: Some designer consider operating hour of the plant is 10-12hours
CHP capacity =392/14 =28 Tonnes / hour
Take 50% extra margin on capacity
CHP capacity = 28 X 150% = 42 Tonnes/hour
Power plant Maintenance Calculations
B-Coal yard design
For 25 MW power plants coal can be supplied through truckes & lories .It is sufficient to keeping the stock of 7-8 days coal in coalshed.
Coal shed capacity = Lenght 50 meter X Width 30 meter X Avg Height of coalheap 4 meters X coal density 800 kg/m3 = 4800 MT
Which han hold the coal for 12 days of full load operation days
If the plant is of bigger size, then the coal is supplied through railway & Wagons & stored at yard..
Yard capacity =Length X Width X avg.Height of 6 meter X Coal densitykg/3
Coal from Shed & yard is then shifted & dozed to vibrofeeder hopper through chain & tractor dozers
C-Selection of bunker capacity
Buker capacity is generally designed for 12-14 hours of full load operation Let us calculate with 12 hours of operation hours Coal consumption in 12 hours = 392 X 12 /24 =196 MT Volume of bunker = 196 X 1000/800 = 245 M3 Take 10% of extra margin on bunker as some of coal stucked on bunker wall surface cannot be used for Boiler. Which is unaccountable So total water volume of Bunker = 245 X 110% = 269.5 take round figure =270 M3