Boiler Fuel Consumption

Well, "we" know the rate of consumption of wood, because "we" can weigh it and "we" know the time it takes for that weight to be consumed. If "we" had a flowmeter on the incoming water and a flowmeter on the steam line, "we" could use simple arithmetic to work it out.

None of these things can be seen from here.

As per #1, measure it. It's not rocket science.

Mr. DUCON

I have one observation in the original posting by Mr. Rajnish and in your reply posting.

The original post does not refer the boiler working pressure and steam temp.

Your calculation indicates the boiling point and the latent heat as 100 Deg.C and 540 K.Cal., Latent heat which corresponds to atmospheric pressure.

If the boiler working pressure is say 15 psi or 1.0 Kg/cm^2 (gauge) the latent heat will be less ( 526.86 K.Cal., ) and Saturation temp., will be 120 Deg.C., and boiling point of water will go up from 100 to 120 Deg.C., as indicated in the steam table and degree of super heat is ignored in this case. This will reflect in the steam output quantity. If the pressure is more, the saturation temp., and latent heat will vary which you know.

You have already considered the boiler efficiency, calorific value of fuel and moisture content of fuel etc.

Thanks,

DHAYANANDHAN.S

you can try the following:

weigh wood billets that are being stocked into the boiler each hour and calculate the mass per hour.there is no known standard rate of consumption since firewood densities vary with the m.c level, species and maturity.

for amount of water that will generate 10kgs of steam.

meter the make up water and use the formula to calculate

mass of steam(kg)= densty, (kg/m³)*volume(m³) where density of water is 1000kg/m³

given 10 kg of steam, then Volume=10/1000 (kg/kg*m³)

=0.01 M³ water

from the foregoing discussion you can calculate the efficiency of your boiler

This is also dependent on the density of the wood your are using for fuel. Oak gives off more heat per pound then pine and so. Need to know a little more info here.

"Formula for calculating fuel:

Fuel Consumption = steam quantity* latent heat / Efficiency * Calorific Value

FOR EXAMPLE:

For 1 tph wood fired boiler-

Fuel Consumption = 1000*540 / 0.75 *3500 = 205 kg/ hr"

https://www.quora.com/How-much-fuel-required-for-1TPH-boiler

As is typical of this forum, the questions by the OP are always way too vague...

First, for a wood fired boiler, your most important question should be "What is the moisture content of my fuel?..... I have seen boiler calculations of fuel consumption vary by nearly 100% because the client had no idea about how dry his fuel was. Remember, if a "wet" fuel is used, you are paying lots of money to make that big cloud of evaporation coming out of the stack.

I have seen fuel suppliers lie, cheat and steal and never supply the dry fuel that the contract documents said that they must ....The engineer who did the calculation is ALWAYS to blame

Secondly, you must make allowances for continuous blowdown and losses in your steam system (valves, traps, etc). If this is a new boiler, I would use a 5-7% allowance. If this is an old used boiler that you bought on the internet a 10% allowance sounds about right.

Thirdly, the type of water treatment you anticipate affects your water consumption, continuous and intermittent blowdown. If you have a modern system with water softeners, etc, the 5-7% allowance above will hold.... If you are taking water directly from the Ebola river right into the boiler, I would allow 15% for blowdown.

Yes, some of these suggestions above are opinions...

But, IMHO, to come up with a reasonable number for water consumption, many factors must be considered.

Tell us more about the facility that you are working on... specifically auxiliary steam equipment ...