Residue after burning of fossil fuelsFly AshBottom AshClinker

CONSTITUENTS OF ASHASH FUSION CHARACTERSTICS

SiO260%Al2O310%Fe2O314%CaO8%MgO2%SO35%OthersRest

IDP1250OCBP1350OCFDP1400OC

EQUIPMENT USED FOR REMOVING ASH AND CLEANING BOILERS FURNACE SIDE AFTER BURNING GRATES SUBMERGED SCRAPPER CONVEYOR. STEAM SOOT BLOWERS. WATER LANCES

ASH HOPPER

ABG VIEW FROM LEFT WALL`

To take up the combustion chamber ash To minimise the unburnt residue. To absorb the kinetic energy of falling slag chunks. To attain an eveness of ash discharge. To store the combustion chamber ash. To attain an air tight seal to the surrounding. To create a surface under boiler for inspections. To minimise the steam explosions.

Traveling Grates2 per boilerAsh rate5.4 t/h (min) & 8.1 t/h( max)Ash collecting time on grates4 hrsMax.Ash loads on grates20 hrsUnder grate air temp.250oC(normal)/310oC(max)Under grate air pressure15 mbarUnder grate air quantity2.1 t/hGrate Width2.1 mGrate length, axle distance / usable 6.4 m / 5.5 mGrate area, total / usable13.44 m2 / 11.55 m2Grate drive motor power4 kw

Sifting De Ashers2 per boilerSifting deasher width1.8 mSifting deasher length6.4 mSifting deasher, driving power1.5 kw

Air tight sealing for the bottom of the furnace. Systematic cooling down of the furnace ash. Quenching of the ash. Ash discharge and conveyance.

Material ConveyedBottom AshDistance between centers15,400 mmCapacity8.1 t/hrConveying Speed0.02 m/secTrough Width1600 mmMotor Installed1.5 kwMotor Speed1500 rpmWater temperature55oC (for normal opn.)60oC (when conveying maximum ash 25t/h)

WORKING OF ABG & SSC

SLAGGINGDEPOSITION OF MOLTEN OR PARITIALLY FUSED ASH PARTICLES ON FURNACE TUBE SURFACES IS CALLED SLAGGING.SLAGGING MAINLY OCCURS ON WATER WALL TUBES.WATER LANCES ARE USED FOR CLEANING THE WATER WALLS.

ARRANGEMENT OF WATER LANCE

WATER LANCES 8 NOS. INSTALLED 2 NOS. PER WATER WALL. 30.360M LEVEL& 34.700M LEVEL (PROVISION AVAILABLE AT 17.2M) PROVIDED WITH TWO PUMPS AT 0M LEVEL TO BOOST SERVICE

WATER PRESSURE. OPERATING WATER PRESSURE 10-12 BAR. WATER FLOW 25-27 T/HR MAXIMUM ANGLE OF JET HEAD IS 90O.

AREA COVERED BY WATER LANCE

FOULINGCONDENSATION OF VOLATILE INORGANICS ON HEAT TRANSFER AREA IS CALLED FOULING.FOULING MAINLY OCCURS ON CONVECTIVE HEAT TRANSFER SURFACES LIKE SUPEHEATERS, REHEATERS & ECONOMISERS.STEAM SOOT BLOWERS ARE PROVIDED IN THE BOILER FOR CLEANING THESE DEPOSITION.

ARRANGEMENT OF STEAM SOOT BLOWERS

24 STEAM SOOT BLOWERS ARE INSTALLED.

6 FOR SH36 FOR RH26 FOR SH26 FOR ECO18 SPACES FOR FUTURE ADDITION ARE PROVIDED6 STEAM SOOT BLOWERS FOR RSDs PROVIDED.4 STEAM SOOT BLOWERS FOR RAPHs PROVIDED.