Hamada Fluidized Bed
Combustion

Travelling Chaingrate

Coal Specification

Coal Size

0~10 mm

15 ~ 50 mm

Coal Price

Cheaper ( ± 23 % )

More expensive

Ash Content

No Requirement, can use
adaro enviro coal with 1 %
ash content

5 ~ 15 %
Chain Grate need at least 5%
ash content to protect chain
from over heating

Volatile

No Requirement

20 ~ 30 %

Combustion System

Furnace
Temperature

Below 1000 °C

1300 - 1400 °C

SOx Problem ?

With Inject CaCO3 can use
coal with high sulfur
content

Must avoid using Coal
with high sulfur content

NOx Problem ?

No, because low
temperature at the furnace

Yes, Because high temperature at the furnace

Ash Melting
Problem ?

No, Because the combustion
temperature below ash
melting point.

Yes, Because the combustion temperature
is above coal ash melting point ( Indonesian coal is young coal with 1100° ~ 1200° C melting ash temperature ). Melting ash will stick to the chain and Boiler tube, difficult to clean and oiler efficiency become low.

Can Mixed
with other
Solid

Yes, Because fuel that still
can be burn will remain
inside silica sand

No, because chain grate
need fuel with same
size and condition

Combustion
Efficiency

Higher, because fuel can stay long inside the silica sand bed until totally finish combustion

Lower, because bigger coal can not finish burning up to the rear of chain grate and will fall down to ash disposal and fine coal will fly and carried away by the induced draft without burning