5 replies to this topic

[José Utrera]

The problem consists that at the top of our crude oil distillation unit (atmosferic), the top vapours temperature is higher than the last packing section (lowest part).

The packing section consiste of 125x structured sulzer, 23.46" high an 15'6" diameter.

I would like to know if there is a simulation sofware or analitical method that we can used to explain this operating behaviour.

Thanks all of you

[fcontrer]

Mr. Utrera:

Only for curiosity, do you check the temperature sensor?,
does the temperature indicator was calibrated recently?.
does your tower highest? if the answer is true, i am not sure (is only an idea) maybe it would be explain for low winds (it sounds very rare)´.

Best regards,

Frank. C

[Luis Marques]

Normally in an atmospheric crude oil distillation you have from top to bottom 1-Naphta cut around 120 ºC, 2-Kerosene cut around 200ºC, 3-Light gas oil cut around 280ºC and 4-Heavy gas oil cut around 320ºC. The column feed inlet is around 375ºC. What cut are you speaking about?

Luis Marques

[Gloria_tan]

I wonder if Mr. Marques is talking about the light distillates
Have you checked the reflux velocity yet

[Milutin]

It is possible that you have vapor – liquid maldistribution in top packed bed. Reason for that can be liquid distributor or packed bed problem caused by improper installation, column upset or corrosion. To confirm this you can try to cut holes in column insulation in level of packed bed and measure column shell temperature, if temperatures have significant difference you have vapor – liquid maldistribution