you have not elaborated on the type of generating plant. Is it a pulverised coal plant? Any coal delivery system is regulated by mercury bin level switches in bins, timers to regulate belt start up and bin limit switches to stop the feeder conveyor feeding the bunkers.

You are unable to do this unless you use trial and error to regulate flow from stockpile to bunkers to pulverrisers to blowers to boilers.

Until you have coal going in a bunker above the boiler you have a no sum game. Its not that simple.

In a 100 ton per hour plant coal is fed into the bunkers every hour depending on the bunker needing coal and timers and horns go off to notify plant operators when coal bunkers are low and restart the drawdown belt or belts from the stock pile.

The belts feeding the bunkers start first-dpending on which bunker needs coal as they are typically bidirectional belts feeding X number of bunkers, then the drawdown belt from the stock pile starts and the coal moves, when that bunker is filled the cross conveyor feeding the bunker stops and then the feeder belt from the stock pile stops per the speed switches.

Timing sequences all depend on the amount of drawdown of the coal in the bunkers. no simple equation or fix. Its easy enough to set x and Y factors to determine filling and drawdown but you can not just ask a blanket question like that as it is trial and error. ■

Izaharris is bang on again.

What you need to do is work out the coal requirement, 1lb/kwhour. Then you can work out the conveyor sizes according to whether the system is twin or single line. Select the running options. Calculate the start-up & run down times for each conveyor, laden & empty. Safety demands a 3 minute warning period before a conveyor can actually be restarted. Your bins must be able to clean off a conveyor in some cases. Pay very special attention to any shuttle conveyors in your line.

If I was young enough I would sit down & put all the data on a spreadsheet, link the cells with the appropriate formulae & then be able to play with anything the customer wanted to change.

Your conveying ability should match the boiler units demands. Sometimes while the coal is running into a reasonably full bunker another boiler is working at condition & in danger of running out. The conveyor in you top gallery, tripper or shuttle, should be able to addres such a situation. etc etc ■

John, thank you for the vote of confidence. leonz ■