9 replies to this topic

[binzee]

Dear All,

 

I intend to work on design of a  new Naphtha Stabilizer Column. Feed Naphtha will be coming from existing atmospheric tower.

 

Can you please advise some guidelines/literature references on how to proceed.

 

Thank you in advance

 

Cheers,

 

 

[sheiko]

I believe you will find the procedure in any good refining book.

 

good luck!

[PingPong]

@binzee

Why do you need to design this? Is this an exicise for your study? Or do you work in the real world?

[binzee]

Its an Internal exercise at our company prior to consulting some EPC 

[PingPong]

You need ro prepare a Basis Of Design (BOD) for the EPC contractor, with information such as:

 

- unstabilised naphtha feed composition, flow rate, temperature and pressure

- stabilised naphtha product maximum C4 content

- stabilised naphtha product temperature and pressure at battery limit

- LPG product maximum C5 content

- LPG product temperature and pressure at battery limit

- Offgas product temperature and pressure at battery limit

- available cooling water supply and (maximum) return temperature

- available cooling water supply and return pressure

- available heating steam temperatures and pressures

- heating oil supply temperature and pressure (if available)

- if to be used for reboiler duty: crude column pumparound data, such as supply and return temperatures and pressures

- available fuel gas and fuel oil properties, supply tempertures and pressures

- available instrument air and plant air data

- ambient air temperature, maximum and minimum

- site elevation above sea level

- aircooler design air temperature

- maximum rainfall and snow fall

- earth quake factor

- ......... (and many other less important things)

 

Condensor needs cooling medium: cooling water or aircooling. If not all distillate can be condensed, then there will be a vapor distillate (offgas) and liquid distillate (LPG).

 

Reboiler needs heating medium: that can be HP steam, or heating oil, or duty from a pumparound from the atmospheric crude column, or a fired heater. Choice depends on reboiler duty, reboiling temperature (depends on column pressure and stabilised naphtha composition), availability of above mentioned heating sources. 

[binzee]

@ ping pong

 

Thank you very much for the details, much appreciated.

 

How about proceeding with the design , any guidelines, specific literature etc.

 

Thanks

[PingPong]

If you have no experience with designing distillation columns, you can only learn by working with an experienced design engineer, not from some book.

 

In any case you need to know the detailed composition of the unstabilised naphtha feed. Do you have that?

 

And you need a process simulator. Do you have access to such? If so, which one?

[binzee]

I have the composition as well as access to simulator however simulator is as good as the inputs. I would be using Hysys but only in the end not as a first step.

[PingPong]

I suggest you start by taking take the C4 and lighter part of the feed, and use Hysys to determine the bubble point pressure of that intended distillate at the achievable condensor outlet temperature. The latter depends on whether you want to use cooling water or aircooling for the condensor.

[binzee]

Thanks pinpong