How to convert CO2 to CH4 or C2H6???

[nong]

Our offshore natural gas plant have 50MMscfd of CO2 which we burn out everyday. I heard about CO2 can be converted back to CH4 or C2H6 by using H2, heat and some catalyst.
I wonder that is it practical or economical? I know H2 is much expensive, so can we obtain H2 from H2O electrolysis or else?
If it's acceptable,this would reduce CO2 at flare, save environment, save the world!!

 

[nbucska]

You must use a neat trick to burn CO2 -- carbon dioxide --
<nbucska@pcperipherals.com>

 

[grumpus]

Reducing CO2 to methane is routinely done in refinery hydrogen plants.

Grumpus

 

[Flareman]

Where is the CO2 coming from? Is it out of the well because you are using CO2 to aid well production or is it actually the product of combustion rather than the discharge because you are burning hydrocarbons?
Either way you probably need to address the reasons for it going to the flare in the first case and possibly change that, before you look at creating an expensive solution to an unusual problem.

David

 

[nong]

Flareman,
CO2 come from the reservoir and we don't use it to help production. We use membrane process to separate it from Hydrocarbon gas, but it's just 75% effective...

 

[joerd]

The usual way of getting rid of CO2 is to inject it back into a separate injection well or send it to the nearest Pepsi or Coke factory.
The common way of H2 production in a refinery is by partial combustion / steam reforming of methane (yield only 35%). Unless you find a source of H2 (or power) that does not generate CO2, which is quite improbable offshore..., you can save the environment by conversion to methane. Regards,

Joerd