Originally Posted by vivekcshekar

Hello,

I am trying to develop an automation program for coal bunker sizing calculation.

What are the parameters & configurations that need to be considered. Can someone suggest a book / design guide / code which i can refer to ?

Also, what is the significance of ventilation system in coal bunkers ?

Originally Posted by Roland Heilmann

Dear vivekcshekar,

if coal is stored indoors, there's gases that exit the coal lumps and which need to be exhausted in order to avoid an explosive or venomous athmosphere.

From the drift of your request it is understood that you are new in this field of technology, so perhaps you try to contact some local specialist (technical schoool / university) first, for basic information.

Here in the forum, you may contact Mr. Ishwar G. Mulani, who also wrote a book "Belt Feeder Design And Hopper Bin Silo", and who might after consultation point you towards fitting literature.

Regards

R.

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What Roland has told you is well said and you should heed his advice.

There is no way to size a coal bunker or bunkers unless you know the desired

generating capacity of the power plant whether it is a cogeneration facility or

strictly for electricity generation.

There are many issues as the design of the coal bunker or bunkers is elevated and

also depends on whether it is going to be a pulverized coal boiler with a wet sump

or a coal stoker.

Most pulverized coal power plants have their bunkers refilled each hour on the hour to top off

the bins at the high limit as they must maintain a back up supply as well to allow the boilers to burn

coal in the event of a conveyor or burner failure.

Stokers and pulverized coal boilers have to be fed by a dozer from a stockpile with a belt feeding

system to fill the stockpile on two or more operating shifts per day. ■

Originally Posted by vivekcshekar

Hello,

I am trying to develop an automation program for coal bunker sizing calculation.

What are the parameters & configurations that need to be considered. Can someone suggest a book / design guide / code which i can refer to ?

Also, what is the significance of ventilation system in coal bunkers ?

There is no base design for coal bunker sizing. This is normally tailor-made for each project. Hence, it is very difficult to collate all related parameters unless the specific use of bunker is known. ■

There are two aspects to bulk storage designs; process performance and structural integrity. The former process is outline in item five of the forum section on 'solid sense' whereas structural considerations lie in the province of mechanical design when the container geometry has been specified. A beginner in this field may initially find it useful to study the article on 'Regimes of flow in hoppers'. ■

You need to define bunkers. Once that has been done we can take it further. So far the bunkers under consideration have been assumed to be bins arranged to store coal for boiler fuel.

Heed JPS's reply along with the rest. Bunkers are custom designed whether above or below ground. Get yourself a Kallenborn Handbook or similar and see what we are talking about. There are also various articles covering the design of stapleshaft bunkers, moving bed bunkers and moving car bunkers. I am the last living resource for moving car bunkers by the way.

For those born out of earshot of Bow Bells.....A real Cockney is born within the sound of Bow Bells. Cockneys have a very well known talent for rhyming slang with important omissions. What do you think Bunker means to a Londoner?

For ventilation background you can download Martin Engineering's Encyclopedia called Foundations. Any edition is more than good enough and I don't know why anyone in this business hasn't got a copy hidden down the back of their screen. ■

Hello,

When,

- Bunker storage capacity is known,

- Bunker bottom discharge outlet dimension is fixed (length and width) and

- Bottom discharge outlet height is also fixed,

then, some information concerned with the bunker sizing (dimensioning) is as below:

1) Generally storage capacity implies net (actual) storage of material according to the feeding method to bunker.

2) The capacity is primarily multiplication of cross section area and height. One should select its combination in such a manner that the bunker together with its supporting structure cost plus bunker feeding equipment cost become most economical.

3) While doing exercise for sr. no. 2, one has to also take into consideration the available space and see that it is suitable for the other concerned equipment (boiler complex, etc.).

Ishwar G. Mulani

Author of Book: ‘Engineering Science And Application Design For Belt Conveyors’. Conveyor design basis ISO (thereby book is helpful to design conveyors as per national standards of most of the countries across world). New print Nov., 2012.

Author of Book: ‘Belt Feeder Design And Hopper Bin Silo’

Advisor / Consultant for Bulk Material Handling System & Issues.

Pune, India. Tel.: 0091 (0)20 25871916

Email: conveyor.ishwar.mulani@gmail.com

Website: www.conveyor.ishwarmulani.com ■

Hello,

I am mentioning some general information about coal storages in coal based thermal power stations. This is known by all people concerned with power plant project engineering. This reply does not imply direct guidance to your specific query. This information will be helpful to you to understand overall scenario.

Coal is a continuously consumed item in thermal power stations. One has to continuously feed coal in boilers which are in operation, round the clock without any interruption. To tackle this requirement, CHP has two types of storages.

The power station receives the coal from mine (or some other source). There can be some interruption for coal transport from mine to CHP. To address this issue, CHP will have ready to use crushed coal storage in the form of stockpiles in stockyard. Such storage could be for 2 weeks or 3 weeks or 4 weeks depending upon the reliability of coal supply as committed by coal suppliers (mine or shipping, etc.). So this storage will take care of the possible interruption in coal supply from outside of the plant.

Then the second storage is in coal bunkers near boilers. The power plant project engineering decides about the possible interruption for movement of coal from storage to the bunkers at boiler complex. Often this storage is for about 24 hours coal consumption by power plant. Therefore the conveyor system from stockpile to the bunkers should never be non-working for more than 24 hours. Generally these have 2 stream system, one working and one standby. The plant operation and maintenance department commits that interruption if any shall be rectified within 24 hours.

For specific information in India, you can contact well known companies / organisations such as TCE, DCPL, CEA, NTPC and hundreds of power stations owned by states. Every industrial country will have similar famous names for referring.

Ishwar G. Mulani

Author of Book: ‘Engineering Science And Application Design For Belt Conveyors’. Conveyor design basis is ISO (thereby book is helpful to design conveyors as per national standards of most of the countries across world). New print Nov., 2012.

Author of Book: ‘Belt Feeder Design And Hopper Bin Silo’

Advisor / Consultant for Bulk Material Handling

System & Issues.

Pune, India. Tel.: 0091 (0)20 25871916

Email: conveyor.ishwar.mulani@gmail.com

Website: www.conveyor.ishwarmulani.com ■

I forgot to advise that the ventilation system should not direct methane gas into zones where it cannot be exhausted. If there is a circular stockpile there will be a reclaim tunnel which should not be intentionally contaminated by methane pockets. Methane can be drawn down by a ventilation system which is designed to exhaust towards the tunnel exit. ■