5 replies to this topic

[Baz]

Hi

 

I (a student) am working on my final section of my design project which is completing a start-up procedure for an ammonia plant that I have designed.

 

The plant has an air separation unit for N2 production, steam methane reformer for H2 production, a carbon capture system for blue H2 production and removal of CO2 (rather than gray hydrogen and releasing CO2 to atmosphere) and finally the ammonia production is complete in the haber bosch process.

 

My question is, is there any guidelines to start-up procedures before the normal operation process.

 

Kind reagrds,

Basmalah. 

Edited by Basmalah, 10 April 2025 - 07:02 AM.

[Pronab]

Baz,

There is specific start-up procedure in an Ammonia plant before normal operation. I assume it is an initial plant start-up. Follow the below guide lines:

1) Front end (from Primary reformer upto Methanator) start-up.

2) Rear end (Synthesis loop) start-up.

In Front end start-up you need to start Primary reformer with burner lit-up and activate primary reformer catalyst including hydrogenation & de-sulfurization catalyst reactors. Prior to that I will assume HTS & LTS catalyst reactors are ready- they are reduced condition. Paralell CO2 removal (in most ammonia plant it is Benfield or MDEA solvent) section are reday.

Primary reformer catalyst  temperature to bring at operating temperature(more than 800C, depending on the process). Start air introduce to secondary reformer followed by gas flow to HTS/LTS reactors and then CO2 removal section. Parallel Ammonia converter reactor heating up/ catalyst to be activated gradually.

Till now purified gas from CO2 recovery section( H2 & N2, traces amount of CO/CO2) will pass through Methanator where traces amount of CO & CO2 will convert to CH4. Once Syn gas (H2 & N2, free from CO & CO2) compressor start and ammonia reactor is ready to take on-line gradually divert flow to Synthesis (ammonia reactor) loop where ammonia will produce. I will assume Ammonia storage tank is ready to storage produced liquid ammonia( Temp:-33C & atm pressure).

Contact me for further clarifications.

Best wishes.

Edited by Pronab, 11 April 2025 - 11:49 PM.

[Baz]

Pronab,

 

Thank you for the help.

[breizh]

Hi,

You may find good pointers in the link underneath.

https://www.asiaiga....m reformers.pdf

As a student, you should not be responsible for this kind of document. This is definitely the scope of senior process or Ops engineers/managers.

Breizh 

[Baz]

Hi Breizh,

 

It is worth mentioning that this is a design project as part of my university course and this is not to be applied in industry.

 

It is for the sole purpose of developing an understanding of procedures and as part of the IChemE Chemical Engineering degree.

 

Regards to the shared link: Thank you for the help. I will read through it to improve my understanding.

[breizh]

OK!

Not knowing your process, I cannot comment much but prior to start to feed any equipment,

you need to make sure you have all the utilities in place (steam, cooling water, chilled water, N2, electricity), all vent lines connected to specific discharge points (let say scrubbers), same for wastewater (treatment unit)

you need to make sure all the equipments are lined up as per PID (manual valves, drain valves,etc).

Very basic for safety reasons.

Good luck

Breizh