PRESENTATION ON COAL

HANDLING SYSTEMS

PREPARED BY:-

ARNAB CHAKRABORTY

MBA-PM

INTRODUCTION

• Coal handling system or coal handling plant (CHS or CHP) are plants used for handling coal from wagon trippler or from stock pile to feed it to the boiler (main objective).

Contd.....

Coal handling

• Coal needs to be stored at various stages of thepreparation process, and conveyed around the CPPfacilities. Coal handling is part of the larger field of bulkmaterial handling, and is a complex and vital part of theCPP.

Contd...

Stockpiles

• Stockpiles provide surge capacity to various parts of the CPP. ROM coal is delivered with large variations in production rate of tonnes per hour (tph). A ROM stockpile is used to allow the washplant to be fed coal at lower, constant rate.

• A simple stockpile is formed by machinery dumping coal into a pile, either from dump trucks, pushed into heaps with bulldozers or from conveyor booms. More controlled stockpiles are formed using stackers to form piles along the length of a conveyor, and reclaimers to retrieve the coal when required for product loading, etc.

• Taller and wider stockpiles reduce the land area required to store a set tonnage of coal. Larger coal stockpiles have a reduced rate of heat loss, leading to a higher risk of spontaneous combustion.

Stacker/Reclaimer

• Stacker/ reclaimer is used to stack coal in the stock pile for future use and reclaimer is used to reclaim the same coal whenever it is required.

• We often do reclaiming when the coal coming from the belt feeder is not of the quality to be feed in boilers.

Belt feeder

• It is a conveyor use in carrying coal from the coal crusher to respective conveyors.

• Crushers:- are used to crush big coals into small pieces of coal or into standard size (i.e. 50mm specifically in KSK MAHANADI POWER PLANT).

Coal crushing system

Ring granulator

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Interlocking for safety

• In case of any belt trip, entire system behind except crusher will stop

• Any other belt of pair will not start on the same discharge belt except 1A&1B

• Corresponding feeder will trip if any belt trips

Cond.....

• Belt & following system except crusher will trip in case of operation of BSS

• In case of excessive belt slipage, low speed due to over load or otherwise, belt not running although motor running, belt snapped than belt and following system will stop through zeero speed switch

• Overloading of more than 600T/hr• Motors are protected against over load, short circuit,

single phasing

OPERATION OF CHP

• Check if all the belts are healthy and the indication is green in SCADA.

• Secondly, check for all possible pull chords manually by sending field operators.

• Take clearance from them and start the siren.

• After 1 min of the siren give start command.

SCADA USED IN CHS

OPERATION OF PADDLE FEEDER

• The Paddle Feeders feed the coal on the conveyor belt from the Track hopper at a controlled rate. The paddle blades projected in the hopper slot scoop the coal from hoppers and discharge it on the conveyor belt running below.

• The following points need to be checked before taking any paddle feeder into service.

• a) The paddle arms are free from any obstruction.

• b) There is no leakage at gearboxes and fluid couplings and the oil levels are correct.

• c) There is no leakage of hydraulic oil, in the case of hydraulically driven paddle feeders, and the oil levels are correct.

• d) The cable reeling drums for correct winding and unwinding.

• e) The paddle feeder is operating only in interlock mode.

OPERATION OF CONVEYOR

• Various conveyors are provided for transporting the coal from Track hopper to Bunkers.

• The following precautions are to be taken before taking any conveyor into service:

• a) There is no oil leakage at gearboxes / fluid couplings and the oil levels are correct.

• b) The Discharge and Receiving chutes are free from jamming and choking.

• c) The Flap Gates are in correct positions.

• d) All inspection doors are in the closed position.

• e) All pull-cords are reset and the EPB is released and ensure that all protections are healthy.

• f) The Alarm Siren is in working order.

• g) Communication facility is available.

• h) The lighting is adequate.

• i) No Permit To Work (Isolation) is pending against that conveyor.

OPERATION OF STACKER/RECLAIMER

• The Stacker Reclaimer is provided to stack the excess coal received from the mines and to reclaim the coal, as and when required.

• The following points need to be checked before returning Stacker Reclaimer into service:

• a) The track is clear of obstructions.

• b) There is no leakage from gearboxes, fluid couplings & hydraulic system. The oil levels are correct.

• c) The availability of power supply is checked.

• d) All operations e.g. travel; slewing, luffing etc. are available.

• e) Brakes are clean and functioning correctly.

• f) CRD cable is free from damage and any obstruction and is tensioned correctly.

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THANKS

TYPICAL CHP