The query is related to a number of power stations facing shortage of coal from linked mines. In order to make up for the shortfall, there is proposal to import coal. These stations receive coal by captive railway system and the imported coal would come by the state railway system.
The calorific value of the coal coming from the linked mines is in the range of 3000-3500 Kcal/ kg. Imported coal is likely to have calorific value of 5800-6000 Kcal/kg. Hence the imported coal cannot be fed to boilers directly since system is not designed for such high calorific value coal. There is need to blend. But these stations were not desgned with coal handling plants suitable for blending.
Each of the station has minimum two(2) cantilevered bucket wheel stacker cum reclaimer operating over yard conveyor with two trapezoidal stockpiles( cross section of stockpile) of 400-600 metre length and 10 m high on either side of each yard conveyor. Boom length is 29 m and trapezoidal stock base is 37 m wide.
It is proposed to stock the indigenous coal in three piles and imported in one pile (total 4 piles available) and use both the S/R in reclaiming mode, the one reclaiming imported coal in a lower TPH and the other one reclaiming indigenous coal in a higher TPH (the TPHs and their ratio being decided to get the required blend/ carofic value), with both yard conveyors discharging coal on common reclaim conveyor ie forming layer of imported coal over indigenous coal or vice versa on the reclaim conveyor belt. A minimum of three transfer houses would be encountered by the reclaimed coal before it reaches the boiler bunker and hopefully it would get mixed up in the chutes to get a reasonable blend.
It is pertinent to mention that coal once reclaimed from stockyard cannot go back to the stockyard and has to go only to the boiler bunker. Coal received in the trackhopper can be sent either to boilerbunker or to stock yard. There are minimum two(2) trackhoppers at each of the stations to separately receive the two types of coal.
It is proposed to send all imported coal to stockyard and reclaimed as and when needed with the blending as described above.
Blending coal in power station
Hello,
The query is related to a number of power stations facing shortage of coal from linked mines. In order to make up for the shortfall, there is proposal to import coal. These stations receive coal by captive railway system and the imported coal would come by the state railway system.
The calorific value of the coal coming from the linked mines is in the range of 3000-3500 Kcal/ kg. Imported coal is likely to have calorific value of 5800-6000 Kcal/kg. Hence the imported coal cannot be fed to boilers directly since system is not designed for such high calorific value coal. There is need to blend. But these stations were not desgned with coal handling plants suitable for blending.
Each of the station has minimum two(2) cantilevered bucket wheel stacker cum reclaimer operating over yard conveyor with two trapezoidal stockpiles( cross section of stockpile) of 400-600 metre length and 10 m high on either side of each yard conveyor. Boom length is 29 m and trapezoidal stock base is 37 m wide.
It is proposed to stock the indigenous coal in three piles and imported in one pile (total 4 piles available) and use both the S/R in reclaiming mode, the one reclaiming imported coal in a lower TPH and the other one reclaiming indigenous coal in a higher TPH (the TPHs and their ratio being decided to get the required blend/ carofic value), with both yard conveyors discharging coal on common reclaim conveyor ie forming layer of imported coal over indigenous coal or vice versa on the reclaim conveyor belt. A minimum of three transfer houses would be encountered by the reclaimed coal before it reaches the boiler bunker and hopefully it would get mixed up in the chutes to get a reasonable blend.
It is pertinent to mention that coal once reclaimed from stockyard cannot go back to the stockyard and has to go only to the boiler bunker. Coal received in the trackhopper can be sent either to boilerbunker or to stock yard. There are minimum two(2) trackhoppers at each of the stations to separately receive the two types of coal.
It is proposed to send all imported coal to stockyard and reclaimed as and when needed with the blending as described above.
Will it work/
Any suggestions?
G. Ravindra ■