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Active Contributor

Join Date: Jul 2007
Posts: 16

# Converting CFM to MMBTU (Natural Gas)

07/14/2007 11:19 AM

Can any one help for the formula to convert cfm to mmbtu ( Natural Gas ) .

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Guru

Join Date: Dec 2006
Location: Hop around Toronto, New York & Karachi
Posts: 1870
#1

### Re: conversion

07/14/2007 3:19 PM

1 Cft gas = 970 Btu. Rounded 1000 Btu

1 mmbtu = 1,000,000

Therefore, 1 cft gas = 1000/10000000 = 0.001 mmbtu

Calculation for example :

1 . AS PER BOILER MAINTENANCE MANUAL:

15000 LB/HR(6800 KG/HR) = 19.6 X 1,000,000 = 19,600,000 BTU

1 CFT GAS PRODUCED = 1000 BTU

CFT = 19600000/1000 = 19600 CFT

MMBTU = 19600 X 1000/ 1000000 = 19.6 MMBTU

AT 80% EFFICIENCY = 19.6 + 4.9 = 24.5

Cost per 1 MMBTU = RS. 208.56 DECEMBER 2005 RATES

COST OF 24.5 = RS.208.56 X 24.5 = RS.5109.72 /HR FOR 15000 LBS/HR

COST/LB STEAM = RS.0.34/LB STEAM

COST/KG STEAM = RS.0.75/KG STEAM

COST/T STEAM = RS.750.00/ T STEAM AT 80% EFFICIENCY

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Guru

Join Date: Dec 2005
Posts: 1598
#3

### Re: conversion

07/15/2007 11:51 PM

Generally true, but do confirm the BTU/Cu Ft numbers from your natural gas supplier. there may be some variation on where the gas comes from. Also, producer gas can be as low as 500 BTU/cu ft.

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Join Date: Dec 2006
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#5

### Re: conversion

07/16/2007 1:46 PM

Txs. Yes you are so right. We never get 970 Btu but between 840 Btu/Cft to 880 Btu/cft but never 970 Btu/cft. He needs to reconfirm from the Gas Company.

Thanks again

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#2

### Re: conversion

07/15/2007 12:20 PM

perfect ducon

Member

Join Date: Apr 2007
Posts: 9
#4

### Re: conversion

07/16/2007 12:35 AM

www.littlegreenhouse.com

For BTU Fuel Consumption Per Hour you will find

cubic ft of natural gas BTU Watts Gallons of Propane

1 1020 293 0.01

Best Wishes