Coal Belt Weighing Scale Calibration Procedure and Calculation

I would also recommend adding a moisture sensor as the heating value of coal is also highly dependent on surface moisture.

If you know instrumentation, you would have an idea how this is done. Could be from a couple of strain gauges as transducers. --this is if you want to have a little project in academics or technical paper for professional engineer application, but i wont recommend this, industrial wise.

There are already design tested and quality checked for this application on the market. Why not use theirs and exempt yourself from too much liability issue.

A 28MW plant has money to buy such. Anyway, what's your existing system for weighing?

Wouldn't weighing and counting the incoming supply vehicles be easier?

Not all the coal being delivered would be used during a given plant operation time frame. A scale placed under the conveyor platform could record the total weight of the system and by knowing the tare weight of the conveyor and the duration of one cycle of belt delivery, a calculation of the delivered load could be made. If it takes 5 minutes to unload the loaded conveyor, then an hour of operation would deliver 12 times the loaded weight of coal, assuming the operation could be a continuous full conveyor for the hour. If a hamper is used to load the conveyor, then the hamper could be weighed similarly each time it dumped. It seems unnecessary to know the exact weight of coal used if you know the tonnage of the coal purchased during a given time period of operation and the units of power produced.. Whatever tonnage is necessary to maintain the operation would be enough to calculate the efficiency of the power plant for a given period of time. Take the cost of coal for a week or month of operation where the reserves are maintained at the same level and the power generated is also constant. That would yield a dynamic coal/power ratio that could be reported as the efficiency or cost of operation per unit of power generated.

When burning any fuel, its always easier to make adjustments to combustion air if the fuel and air are metered. If a weigh belt is Not used, its really just a guess.

The old days of more fuel add more air are going away.

I like to use the comparison of an automobile.

It used to be carburetor. Now precise fuel injection to maximize efficiency.

You could do the world a favor and covert over to natural gas that comes equipped with a flow volume meter. Much cleaner, not as messy and much easier to calculate

You probably should let the OEM representative do the install, calibrate, and verify part of the procedure, and make arrangements with them to have this checked on a regular basis if at all possible. Otherwise, they should supply you with a complete manual for their product.

This might be a strain gauge belt weighing device, or it might just be based on power draw of the conveyor motor, depending on the base power draw for empty belt, and that when belt is heavily loaded. One would be way more precise and accurate than the other, I suspect.

Most of the good ones use a load cell or a series of load cells sensing the mass of the belt as it travels past. These load cells should only be calibrated by a professional.

The belt weigher must also integrate belt speed with the sensed mass, thereby providing mass transport rate - usually through its own dedicated microprocessor.