vent system

[MMED]

Dear Engineers and experts

We have a multiple wash and storage tanks venting to common line to flare. This line suffered overpressure due to blockages cuased by accumulation of impurities leading to instability operation of these tanks and malfunctioning of the breather valves.

Note that there's no liquid traps along the line and no knock out drum is installed. The vent lines are vey old with old fashioned design.

Can anyone hep with recommendation and what should be done to design a new vent system to avoid such problem?

Best Regards

 

[LittleInch]

What exactly was "blockages cuased by accumulation of impurities "

That's all very corporate BS type words.

Did the flare line have low speed?

what impurities? Its a flare live. Its supposed to contain impurities.

Continuos slope down to KO drum is required with no low spots.

 

[MMED]

What exactly was "blockages cuased by accumulation of impurities "

That's all very corporate BS type words.

Did the flare line have low speed?

what impurities? Its a flare live. Its supposed to contain impurities.

Continuos slope down to KO drum is required with no low spots.

Hello Sir

Thank you for your quick reply and sorry for not providing as many details. This is an old central pumping station receiving oil from different remote stations and the facility piping and associated equipment suffering severe corrosion at some areas due to lack of maintenance and appropriate integrity management system.

Regarding the type of stuff causing increased pressure in the lines to flare are sort of sludge and solids build up. Yes, the flare line has low speed and I agree that it is supposed to have impurities.

Is there anything to be considered regarding the line size? Does is need to be the same diameter along the way from the source to the flare? Is it required to increase the velocity ?

Kind Regards

 

[georgeverghese]

Many reasons for this, and all will need addressing. Hire a senior facilities / process engineer to study and submit a report. At the worst, tank design pressure may be inadequate. Modern practice requires recovery of hydrocarbon vent streams, so a vapor recovery unit may be in order also to keep up with the times.