S-200 Ammonia Converter

[dhproeng]

Can anybody tell me maximum service life of S-200 ammonia converter.

[tosif]

typical life of S-200 catalyst (HT - KM1) is 10~12 years versus guaranteed life of 05 years. Where as typical replacement life of S-200 basket (mechanical) is ~ 20 years being non-pressure part. But it would be better to recycle your evaluations with OEM (HT) against catalyst or basket replacement.

[dhproeng]

Thanks brother for your reply.
I am just asking for S-200 basket(mechanical). Actually we want to shift from s-200 to S-300. Is there any refrence for that the life is 20 years or just it is experienced based statement. how can we determine that noe it is the time for replacement or just we have to consult OEM(HT).

[whaider]

Life depends on material of construction of your basket which may vary from case to case even in same configuration. There is more into it than just life, as with S-300 you will achieve same production level at relatively lower synthesis loop pressure so there is definitely some economic benefit into it which also needs to be considered.
I would suggest that you read following papers of AIChE and probably these can help you a bit.
1) Replacement of an S-200 basket with an S-300 basket in a 24-year-old ammonia plant, 2008
2) Engro’s Experience with Implementation of a S-300 Converter During a Normal T/A, 2003
3) Experience of Ammonia Converter with Catalyst Leakage and Repairs, 1999
4) Crack Formation in Welds in the outlet lines of an Ammonia Converter, 1991

[tosif]

so if you talking about replacement of S-200 basket with the same one (in-kind with S-200) then yes obviously you have to refer to OEM with your operating parameters details. So that it can evaluate the stresses over the mechanical parts due to high temperatures and reactions. But if you planned to increase the production per loop by switching from S-200 to S-300 then you have to evaluate the dynamic and balance of whole plant.
Anyhow as per our experience with such type of replacement, OEM generally refers to the effective service life of 12 years for basket and recommend to replace after 20 years. (but certainly based on operating conditions)
Remember one thing that after upgrading ammonia conversion per loop will be increased along the delta T across the converter. That results in higher outlet temperature. Do verify your converter's mechanical design to allow you to that new higher temperature, along increased in steam generation in waste heat boilers.