9 replies to this topic

[betty]

Regarding this task:

How to Convert from ASTM D86 into TBP?

http://www.cheresour...stm-d86-to-tbp/

Is there any other method used to convert ASTM D86 into TBP, without including the Coefficient a Coefficient b?

My task,

The end point for Heavy Gasoline is 210 C and the Flowrate is 17 m3/h



The new target for end point is 185 , by drawing off the HG flowrate into 5 m3/h

But new target for end point is 185 doesn't exit and remains between (195-200 C)

How could I achieve 185 C? and How could I know the End point when the flowrate 5 m3/h?

Regards

[Technical Bard]

The conversion from ASTM to TBP (and vice versa) can only be achieved using the method published in the API TDB.

With regard to your other problem, you clearly have a problem with too much heavier material high in the column. In addition to reducing the heavy naphtha draw, you will need to increase heat removal in the kerosene / light diesel pumparound. This will help keep that heavy tail in the kerosene draw.

[betty]

Thanks for replay,

you meant API TBP method which is including Coefficient a Coefficient b and it is applicable for CDU products streams ..

In my case , I have RFCC and the products are Vapor HC at the top , Heavy Gasoline, LCO, (HCO which is only circulation) and Fuel oil..

At 185 C the Heavy Gasoline becomes very light comparing with 210 C..

So how could I acheive 185 C with heavy Gasoline product? And what the End point if the flow rate is 5 m3/hr.

Regards

[Technical Bard]

The API Technical DataBook provides the methods for converting TBP to ASTM D86 / D1160 distillations (and the reverse). These are applicable primarily to crude, but can be used for cracked stocks and hydrotreated materials as well (with some caution).

I cannot tell you what the endpoint should be for a given draw rate without significantly more information. As you are running an RFCC, my comment still applies, just increase the heat removal from the LCO pumparound while you draw less material from the heavy naphtha draw. If you just reduce the HN draw without changing the heat removal in the column, you just push more material overhead. Your HN will get "heavier", not lighter.

[betty]

Thanks for replaying and for correcting my info and I will suggest your procedure regarding heat removal.

I will go through, API Technical DataBook and discover the right method.

But could I know the "significantly more information" which I have to provide for you?.. (Volume % & Flowrate?)

Regards

[betty]

Thanks, I got the procedure + distillation curve..

[Profe]

Hi Betty

About your question, review this "How convert ASTM D86 to TBP" subject in this forum

http://www.cheresour...__+how +convert

Good luck

Edited by Profe, 19 July 2012 - 04:01 PM.

[Profe]

Hi again

Attached the spreadsheet for convert ASTM D86 to TBP according with API Technical Data Book.

I think that is useful.

Attached Files

•  API ASTM - TBP.xlsx   12.17KB   30 downloads

[betty]

Thanks Profe, it is really very useful..

[gegio1960]

I'm used to see this kind of problems managed thru a process simulator (ie Hysys, Unisim, PROII....).
When you have the simulation of the tower:
- you have available all the ASTM and TBP curves of the various streams
- you can easily see the effect of the changes of process conditions on the properties of the involved streams