1 reply to this topic

[taswin]

Hi

i was wondering what is the technical consideration one needs to consider while replacing fuel gas with natural gas (NG). Some things which come to my mind is:
1) Burner design - even though NG is predominantly Methane & FG has varyin percentage of composition , does it have any effect on burner design
2) Flue gas compostion- just a thought not sure how relevant it is!!

Also has any one has an experience of using NG instead of Naptha for steam reformer/Hydrogen generation unit. With my knowledge the naptha has Carbon molecules higher than NG but ultimately Naphtha is reformed to mix of CO , CO2 & H2 ( shift reactions). Was wondering would it require any major design change ( may be in terms of catalyst design)?

Aswin

[iplan]

Taswin,

Regarding replacing fuel gas in burners,

1. The burner heat release will change with Molecular weight. As the gas gets lighter, more gas would be required for the same heat duty and the burner upstream pressure would increase. (For the same pressure at the upstream of burner, using lighter fuel would mean less heat release).

2. The flame velocities would also change though I am not sure how they affect the furnace.

Regarding the Naphtha/NG in steam reforming.

1. Naphtha steam refforming catalyust will be Nickel catalyst promoted with potash for reducing carbon deposition. NG catalyst need not be with Potash.

2. Steam / Carbon ratio will be less for NG when compared to Naphtha.

3. New catalysts can be reduced with feed gas if feed is NG. If it is naphtha, separate reduction need to be carried out.

4. Differences in Sulphur in feed in case of NG and Naphtha need to be considered for changes in feed pretreatment.

Thanks