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Participant

Join Date: May 2011
Posts: 2

### Boiler Fuel Consumption

09/21/2012 1:07 AM

We have one 1 Ton capacity thremex fire tube boiler and we are using wood as fuel. how we calculate the fuel consumption per hour and quantity of water used for making 10 kg steam.

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Join Date: Jan 2007
Location: In the bothy, 7 chains down the line from Dodman's Lane level crossing. Kettle's on.
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#1

### Re: boiler fuel consumption

09/21/2012 3:21 AM

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.

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#2

### Re: boiler fuel consumption

09/21/2012 6:02 AM

10 kg water → 10 kg steam.

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#3

### Re: Boiler Fuel Consumption

09/21/2012 12:05 PM

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

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#4

### Re: Boiler Fuel Consumption

09/22/2012 12:28 AM

Quantity of water to make 10 kg steam is 10 litres of water. 1 Tph = 1000 kg or litres or 1.0 m3/hr

To heat 1 kg of water from 0 C(37 F) to 100 C(212 F) 100 kcal are needed.
1 Kcal is the quantity of heat needed to rise the temp of 1 kg of water by 1 C.
0.7 to 0.8 of kcal is the quantity of heat needed to rise the temp of 1 kg of wet compost by 1 C.

1 kcal = 3.968 BTU
1 BTU = 0.252 kcal

to convert 1 kg of boiling water to steam about 540 kcal are needed.
so >
1 kg of steam = 100 kcal + 540 Kcal = 640 kcal

and the steam will supply upon condensation 540 kcal + 1 kg of 100C water(100 Kcal)

Calorific value wood 3500 Kcal(ranges 3000 Kcal ~ 3900 Kcal) So 10 kg steam x 640/3500= 1.8 >2.0 kg wood or 1 Tph = 1000 kg/hr x 640/3500 = 183.0 kg/hr. Depending on your boiler efficiency and calorific value/moisture content % which you have not mentioned It will average between 200~250 kg/hr with feed water 100C.

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Participant

Join Date: May 2012
Posts: 2
#5

### Re: Boiler Fuel Consumption

09/22/2012 3:25 AM

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

Guru

Join Date: Aug 2010
Posts: 523
#6

### Re: Boiler Fuel Consumption

09/22/2012 6:03 AM

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.

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Join Date: Aug 2012
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#7

### Re: Boiler Fuel Consumption

09/23/2012 1:28 AM

Post #4 by Ducon and then by fixitorelse refers. This is just an add on.

The basis of calculating Boiler Fuel Consumption is kg of fuel / kg of steam produced. The measurement of kg of wood has been discussed above by our learned friends so very correctly. It is now the measurement of kg of steam that you produce that need to be measured. If you have a steam flow meter , then it is simply a quick read off. But assuming that you do not have one in your system, then you need to measure the quantity of feed water consumed / hour - this can be measured from the Feed Water Tank by level difference . But just one point to note is that in the boiler, there may be the effect of evaporation and continuous blowdown. Normally we allow for about 10% for this, which means that the the quantity of water calculated need to be reduced by 10% before you work out the water consumption.

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