burner for hydrogen-rich fuel
burner for hydrogen-rich fuel
(OP)
Dear Readers,
We would like to introduce our excess hydrogen-rich offgas to our fuel gas system. The major concern is the hydrogen content on the fuel gas would be between 50-60 %. What should we do to ensure that our burner is suitable for high-hydrogen service? What is the limitation of hydrogen in the fuel gas? Is the limit is the material or operational?
Thanks
We would like to introduce our excess hydrogen-rich offgas to our fuel gas system. The major concern is the hydrogen content on the fuel gas would be between 50-60 %. What should we do to ensure that our burner is suitable for high-hydrogen service? What is the limitation of hydrogen in the fuel gas? Is the limit is the material or operational?
Thanks





RE: burner for hydrogen-rich fuel
the problem with hydrogen is its very low density. So inspite of its higher calorific value you have to burn a larger volume of gas to get the same heat release. The other two slightly minor points are
1. reduced flame emissivity compared to normal fuel gas which will reduce the radiation section heat absorption.
2. Requirement of more stochiometric air than normal fuel gas for a given heat release.
So expect problems in:
1. Fuel gas header pressure drop
2. Fuel gas control valve
3. Requirement of more burners than for Fuel gas
4. Furnace draft problems and positive pressurisation
5. Inability to consume the gas and resultant flaring
In short it is hydraulics of Fuel gas and Flue gas you have to work on. get the Volumetric flow of the new fuel gas for equivalent heat release and work the hydraulics based on it.
Best of luck
RE: burner for hydrogen-rich fuel
Comment on above from Reena : My experience is that hydrogen has a lower calorofic value, as measured in MJ/nm3, than typical fuel gas mixes in refineries......
RE: burner for hydrogen-rich fuel
RE: burner for hydrogen-rich fuel
Application is Ethylene Crackers (Furnaces).
Cheers
RE: burner for hydrogen-rich fuel
Cheers
RE: burner for hydrogen-rich fuel
A little about hydrogen; first look at the LEL and UEL; 4% to 92%. Now, compare that to the fuel you are using. You will find that the LEL and UEL window for hydrocarbons is very small compared to hydrogen.
I can ignite the H2 with any amount of hydrocarbons with limited air using my Plasma RamJet. Operating rich or lean is not a problem. The sole problem is simply a matter of electrical costs. If you can afford the costs, then the Plasma RamJet will ignite it. However I prefer to crack the hydrocarbons prior to mixing with hydrogen. Thus, the entire fuel stream consists of hydrogen and carbon or hydrogen and CO (syngas). It burns quite well in the Plasma Whirl Reactor. see www.oxilume.com
Todd
Todd
www.oxilume.com
RE: burner for hydrogen-rich fuel
Like others above, I have seen projects with this much hydrogen done with refinery heaters and the result was successful.
Depending on the calorific value of the original system you may or may not require new burner trains. In one application in the past we only had to change the burner drawers, not the fuel gas trains. If you are thinking to switch between this fuel and the original fuel your problems may be more challenging.