What are the changes required when a hydrogen generation plant feed which is originally designed for naphtha is to be run on natural gas (as a feed)?
Answers
|
06/07/2010
|
A:
|
J Sudeep, SATORP REFINERY, jsudeep81@gmail.com
The following points must be taken in account
1. Whether the reformer catalyst is designed for running in NG feed.(catalyst vendor must give the guarantee)
2.S/C ratio can be minimised but reformer I/L& O/L temperature must be raised slightly higher may be +/- 10-20 deg c in order to reduce the methane slip.
3.PSA tunning if required to maintain the product purity.
4. NG normally will be pure sulfur species will be very very minimum,hence you should go for dosing (organo sulfur compound like DMDS) inorder to maintain COMOX/NIMOX bed - (pretreatment section) in active form, if the same not done any fluctuation in feed purity will result in sulfur slippage to reformer.
5.Steam tracing of NG related pipe lines.
|
|
03/07/2010
|
A:
|
J Sudeep, SATORP REFINERY, jsudeep81@gmail.com
While changing from Naphtha to Natural Gas following points to be considered:
1. You have to operate at higher reformer outlet temperature to reduce the methane slippage,
2.Whether your reformer catalyst is designed to handle natural gas or not?
3.Normally natural gas have very less sulfur content, as a result your hydrotreater may go inactive , hence additional dosing system (sulfide compound) required to keep the comox/Nimox bed in active form.
5.If Natural gas have mercury/halides the pretreatment section catalyst must be changed to avoid mercury /halides slippage.
6.PSA beds tunning required for maintaining the product purity.
7. Heat tracing were ever required since NG, will under go Joule Thomson effect
|
|
06/06/2010
|
A:
|
Balasubramanian Iyer, Nexen CNOOC Limited, balasubramanian.n@aol.in
While changing from Naphtha to Natural Gas The following points to be considered:
1. The feed pump which was pumping naphtha is no longer needed.
2. Compressor for natural gas.
3. The plant is going to operate on lower steam to carbon ratio than in the naphtha case.
4. The exotherm and the endotherm which where prevalent in Pre Reformer will not be much witnessed in case of Natural gas feed as the feed is almost Methane.
5. if used as fuel also in reformer section then burner needs to be checked.
6. the feed exchangers are to be checked for required duty.
7. Refomer Heat duty is also changed due to low steam to carbon ratio.
These are the major points to be checked.
|
|
12/02/2010
|
A:
|
Syamantak Dhar, Indian Oil corporation Limited, syamantak.dhar@aol.in
Operation-wise a few of the following changes might be required to accommodate the change in feedstock:-
1. You will need to have a compressor to increase the pressure to the designated severity. Usually if the change was conceived earlier then the Nitrogen Circulation Compressor would serve the purpose and it will be designed to take care of that.
2. The Temperature profile across your Pre-Reformer will not be there as the majority of the feed stock is very light in nature (Methane mainly). So there will be endotherm across the Pre-reformer bed.
|