Steam Generation

[kewilson8]

Was wondering if anyone could help me determine how much natural gas I will need to generate steam. I am also using excess hydrogen to create the steam. The excess steam is 0.5 kg/s and I am required to generate 10 kg of steam per second.

 

[TBP]

This will give you a pretty accurate estimate. Most industrial boilers will add about 1000 BTU to 1 lb of feedwater to make 1 lb of steam. At 80% boiler eff and about 1000 BTU/ cubic foot of gas, you'll need to burn 1,250 BTU of natural gas to make a pound of steam.

 

[kewilson8]

Thanks heaps,

Do you know how much hydrogen is required to create one pound of steam? The process I am using generates excess hydrogen and instead of burning it in a flare we have decided to use it to generate steam in combination with nat. gas.

 

[davefitz]

enthalpy of formation of nat gas ( methane)
= 32211 BTU/lb mole, and for hydrogen ( to H2O) =
104036 BTU/lb mole.

Careful with mixing H2 with CH4: the flame propagation rate increases and an increased risk of flame blowback is possible. The burner manufacturer needs to be apprised of the range of H2 concentration and the burner design adjusted accordingly.