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INDUSTRIAL TRAINING REPORT BY SHISANU SEN

Email Id- shisanu.sen@gmail.com

BUFFER HOPPER

NO.- 16 in number(4 for each unit 2 working 2 standby)

Capacity 35 cu. m up to high level

Volume of air lock tank 1.41 cu. m (2 no. below each buffer hopper)

Bag filters 81 in each hopper

material- nomex

150 mm dia*2750mm long (each)

The function of buffer hopper is to collect the dry ash from ESP & APH through vacuum line &

separate the ash air mixture where ash accumulated in buffer hopper & air been discharges

through vacuum pump discharge line & then transfers the ash to transport air through air locktanks by vacuum to pressure equalizing method through equalizing valves, upper gates & lower

gates.

INSTRUMENT AIR COMPRESSOR

NO.- 3 in number(2 working , 1 standby)

Flow rate.- 14 cub. m/min(each)

Discharge/pressure.- stage1:: 1.8 kg/sq.cm. stage 2:: 8 kg/sq.cm.

Motor in air drying plant capacity:: 1800 N cub. m/hr.

The function of instrument air compressor is to deliver 6 kg/sq. cm. air for pneumatic operated

actuators operation, pulsating air for bag filters & fluidizing air for buffer hoppers.

DRY ASH SILO

NO.- 5 (1-2-3 FOR UNIT 1 & 2 & 3-4-5 FOR UNIT 3 & 4) silo no. 3 is for

saleable purpose.

Capacity.- 2949 cu.m

The function is to store the dry ash coming from buffer hoppers through pneumatic conveying

system through transport line. Two types of unloading system ::

1. unloading in belt conveyors through hydro mix dust conditioners in moist form

2. unloaded in closed tankers through rotary feeders in dry form.

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P a g e |

INDUSTRIAL TRAINING REPORT BY SHISANU SEN

Email Id- shisanu.sen@gmail.com

PIPELINES

NO.- 8 LINES (2 in each unit) total 4 unit.

Length:- 1 km each

The function of the pipelines is to transport ash air mixture from buffer hoppers to silo storage

tanks.

BOTTOM ASH HANDLING SYSTEM

The bottom ash impounded into bottom ash hopper (194 cu. m.) & feed into clinker grinder

through bottom ash hopper discharge gate. After clinker grinder the slurry line is evacuated by

hydro ejector (inlet pressure 20 kg/sq.cm. & outlet pressure 4 kg/sq.cm) & sent to hydro bin (650

cu.m) through slurry line (1 km long).

Fly ash collected in silos & bottom ash decanted in hydro bins transported to ash moundarea by a series of belt conveyor system & ash is dumped in systematic manner.

Normally ash is dumped in permanent ash mound area through spreader 1 & 2. During rainy season or system non availability, ash is being dumped in temporary stock

yard through stacker from where it is reclaimed to the permanent ash mound through re

claimer.

When permanent & temporary stock yards are not available ash is being dumped inemergency stock yard, from where ash transported to permanent ash mounds through

mobile equipments.

Each silo is provided with 3 hydro mix dust conditioner, 2 operating 1 standby for removal &conditioning of fly ash in moist state.

Each silo is provided with 3 more outlets for removal of fly ash as an alternativearrangement. Each outlet is having one manual isolating valve, one solenoid operating

valve, one rotary feeder & one telescopic chute.

Each silo have capacity 2500 MT whereas hydrobin capacity is 650 M CU.