Coal Efficiency

[karalahana]

Hi, I wonder what is needed to do as extra if we do give up using 400 kcal/kg coal to use a 300 kcal/kg one in a 250 Mwatt coal plant?

 

[Marmite]

Burn more coal.
Regards
Marmite

 

[karalahana]

so u need to have bigger boilers maybe?

 

[alehman]

That's what you need. The design of the boiler may need to be changed to handle the lower heat content. That discussion is probably better suited to the boiler forum.

Alan
“The engineer's first problem in any design situation is to discover what the problem really is.” Unk.

 

[waross]

The reason that the coal is a lower heat value may be more important than the heat content. The handling properties may be completely different. You may have jamming problems with your coal handling system.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[burnt2x]

For the same heat requirement, you need to feed more kg of 300kcal/kg coal compared with using 400kcal/kg coal! The freeboard area being the same, you will have combustion problems as you'll have more coal inside your boiler than it used to.
Still, I can't be very sure since you haven't told us what type of coal boiler you have there! Maybe it will work with your boiler setup or it won't! Best to have help from a boiler specialist.