8 replies to this topic

[kaidlut]

Dear all, 

 

 

 

    I work in a HYCO plant, which process is SMR+coldbox ,and our feedstock is nature gas, recently one question puzzled me a lot.

 

  

 

    Our reformer tube have a hot band problem，someone says we need to add a new Pre-reforming Unit , because the feedstock component is heavier than design.( the design composition is C1>94% , C2<3.76%，but the  actual composition is C1 89% C2 4.78%). But the Pre-reforming Unit is very expensive.

 

    our reforming catalyst type is JM KATALCO 57-4Q，Johnson Matthey have another type of catalyst KATALCO 25-4Q which Contain potassium，and KATALCO 25-4Q can  prevent carbon deposition effectively.

 

 

 

    My question is , Do we have to add a new Pre-reforming Unit, or we just need to chang the catalyst type from  57-4Q to 25-4Q ? Thank you .

[Pilesar]

I have seen hot bands caused by improper loading and leaving a bridge of catalyst above a gap. I have also seen it caused by a bad batch of catalyst from the manufacturer. Unless this is a new batch of catalyst load, neither of those explanations would apply. I would give strong weight to Johnson Matthey opinion. If you do not trust them as a catalyst expert, then what other option do you have? Catalyst change seems much cheaper than adding capital equipment.

[seuenergy]

I agree with Pilesar's opinion. Contact with more vendors, and do root cause analysis. 

[breizh]

Hi,

Yes, Johnson Matthey is a reputable company, you may want to contact Axens for a second opinion and support.

What is the shelf life of the catalyst? 

Only you can trouble shout the reactor with data on hands.

my 2 cents.

Breizh

[kaidlut]

Thank you for your reply.

 Actually, It's Johnson Matthey who suggested us to add a new Pre-reforming Unit.

 

I have seen hot bands caused by improper loading and leaving a bridge of catalyst above a gap. I have also seen it caused by a bad batch of catalyst from the manufacturer. Unless this is a new batch of catalyst load, neither of those explanations would apply. I would give strong weight to Johnson Matthey opinion. If you do not trust them as a catalyst expert, then what other option do you have? Catalyst change seems much cheaper than adding capital equipment.

[kaidlut]

Thank you , how to contact Axens?

Hi,

Yes, Johnson Matthey is a reputable company, you may want to contact Axens for a second opinion and support.

What is the shelf life of the catalyst? 

Only you can trouble shout the reactor with data on hands.

my 2 cents.

Breizh

[breizh]

Hi,

A Google search, probably similar result with Baidu. 

 https://www.axens.net/

https://www.axens.ne...a/axens-beijing

Note :

You should have a technical report from Johnson Matthey explaining the reasons why they advise you to add an equipment. This could be the base to discuss with competitors.

 

Good luck

Breizh

[PingPong]

    Our reformer tube have a hot band problem，someone says we need to add a new Pre-reforming Unit , because the feedstock component is heavier than design.( the design composition is C1>94% , C2<3.76%，but the  actual composition is C1 89% C2 4.78%). But the Pre-reforming Unit is very expensive.

 

A pre-reformer should not be required for natural gas feedstock.

It is not even required for LPG (C3/C4) feedstock.

In fact, I have seen designs in the past for naphtha feedstock that did not even have a pre-reformer.

 

Just to be sure: you should obtain a detailed analysis of your natural gas feedstock to see if it has a tail of aromatics. C2 content only is not relevant.

 

You should check the Steam/Carbon ratio you are operating on. Is it as specified by the design company and the catalyst supplier?

How reliable is your steam flow measurement? Have it checked by your instrumentation people.

 

How about firing? Is there a problem with the burners resulting in poor heat distribution and coil overheating at some locations? Or even flames impingement on the tubes?

 

And ask yourself: when did this problem start? What was changed just before that?

Edited by PingPong, 03 May 2023 - 05:02 AM.

[kaidlut]

Thanks a lot ,sir . Your reply is very valuable to me !

 

    Our reformer tube have a hot band problem，someone says we need to add a new Pre-reforming Unit , because the feedstock component is heavier than design.( the design composition is C1>94% , C2<3.76%，but the  actual composition is C1 89% C2 4.78%). But the Pre-reforming Unit is very expensive.

 

A pre-reformer should not be required for natural gas feedstock.

It is not even required for LPG (C3/C4) feedstock.

In fact, I have seen designs in the past for naphtha feedstock that did not even have a pre-reformer.

 

Just to be sure: you should obtain a detailed analysis of your natural gas feedstock to see if it has a tail of aromatics. C2 content only is not relevant.

 

You should check the Steam/Carbon ratio you are operating on. Is it as specified by the design company and the catalyst supplier?

How reliable is your steam flow measurement? Have it checked by your instrumentation people.

 

How about firing? Is there a problem with the burners resulting in poor heat distribution and coil overheating at some locations? Or even flames impingement on the tubes?

 

And ask yourself: when did this problem start? What was changed just before that?