Cryo pros says getting H2 from syngas is easy

General Discussion
#1

Hi - I got a response from an established cryogenics gas separation company and I explained biomass syngas and that I wanted to get the individual gases out. They said “um …that’s tough but we can get the Hydrogen pretty easy”. Score!

That leaves the rest of the gases still. Water Gas Shift makes Carbon Monoxide into Hydrogen with the addition of water vapor over a catalyst.

I want to believe the rest of the gases will remain inert through through low temp WGS and then we’ll be back to a Hydrogen heavy stream again where Hydrogen is easy to extract. Score!

The remaining gases can be discharged to the atmosphere or the Carbon Dioxide can be sequestered… Methane should be combusted or separated if doing so is economically viable.

Phillip

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#2

No the water shift converts H2O into H2 and CO with the addition of carbon forming with the oxygen in the water melecule sepperating it from the H2. The Co2 is not part of this process but is converted in a simalar way with the Oxygen reacting with the free carbon in the charbed.

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#3

Thank you Matt I appreciate the input. I think we said the same thing but you used the reactants correctly.

H20 + CO goes to CO2 + H2

Yes or no

Phillip

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#4

CO + H2O ⇌ CO2 + H2.

Is that wrong? That’s posted all over the net

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#5

I’m not familiar with char bed in WSG. You make it sound like this reaction happens right in the gasifier. I didn’t run across this at all

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#6

Yes there is a charbed WSG thank you Matt. Good job!

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#7

Post deleted by author

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#8

No its

H2O + C goes to CO + H2

You also have Co2 that is converted from oxidizing the charcoal. This creates Co2 this reacts further in process to convert to CO.

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#9

I did it wrong
this the main, heat producing, reaction
O2 + 2C ⇌ 2CO here C represents charcoal for simplicity

If EGR is used to ‘temper’ ie cool the system
CO2 + C ⇌ 2CO
H2O + C ⇌ CO + H2
Maybe you can see the wisdom of insulating the reactor?

Real systems are very complex, producing varying amounts of methane, vinegar, H2S and trace amounts of many other hydrocarbons, in addition to CO and H2.

*Note: H2S combines with condensate water to make H2SO4. Therefor ‘sour gas’ as is common in fossil fuels. There is relatively little sulfur in wood and most kinds of biomass, but it is still a problem.
Rindert

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