# City Gas Flow Rate Calculation

Currently I am working on city gas network project in Mojokerto. This is my first experience. You can see in my curriculum vitae what I actually do in this project.

My job is relatively more simpler than what I did in LNG project. I need to prepare four process documents which are:

• City gas flow rate calculation
• Line sizing
• Hydraulic analysis
• Polyethylene pipe thickness calculation

I intend to post a series of city gas network in the future, in addition to LNG project. So please wait for my next post and like and subscribe if you find it useful 😉

As the first post of the series I want to share you how to calculate required city gas flow rate if we want to deliver the gas for 10000 houses for example.

Step 1 : Check Burner Power

I checked burner power of several stoves and found it varied.

We can conclude that burner power is ranging from 3.4 kW to 4.8 kW. Let’s use 4.1 kW as basis of this calculation.

Step 2: Check HHV of Source Gas

Every source gas has different composition thus HHV is also different. Ensure you have correct gas composition. In this example we assumed HHV of gas is 1000 BTU/scf.

Step 3: Begin the Calculation

1000 BTU/scf = 1055 kJ/scf

Gas consumption of every stove = 4.1 kW x 1 SCF/(1055 kJ) = 0.00388 scf/s.

Assuming cooking only takes 8 hours/day (maximum):

0.00388 scf/s x 8 hours x 3600 s/(1 day) = 111.74 scfd = 0.0001117 MMscfd

For 10000 house connection, required city gas flow rate to be =

0.0001117 x 10 000 houses = 1.117 MMSCFD