Start-up pump design

[Coops]

During a platform shutdown, problems are experienced with accumulation of water and dead crude. The Main Oil line export pumps (6 stg centrifugal) are not designed to pump these fluids (higher density), leading to problems with high discharge pressure trips and seal damage.

I want to put in a "start-up" pump to disperse these fluids; it must provide the 150barg
required for pipeline entry. The flow rate of this pump is not too important somewhere around 5 bbls/min (50m3/hr) would do the job. Pressure support to the suction could sometimes be a problem, depending on how quickly the 3rd stage separator can be pressurised (0-8barg), if this pump had the capability to suck it would be a bonus.

Has anyone experienced similar problems?
What pump design would you suggest for this purpose?

 

[bhwtam]

Coops,

When I work with sludge, I experienced similar situations as sludge will accumulate in the piplines causing problems during the start-up of the pumps. There are two ways to solve our case, one is pass high pressurized water to flush the pipeline after pump stop and before pump start. Second is provide a recirculation pump to keep the sludge flowing between the discharge tank and inlet manifold.

Hope this may help you to generate some more fresh ideas


bhwtam

 

[d23]

Coops

Two other possibilities:

After shut-in do you have compressed gas available to help blow down the line? When gas expands it will add lift if you have a way to inject it that may help.

On your current pipeline pump is the intake and discharge rated for a higher pressure or can it be upgraded for a reasonable price? A pump in series with your existing pump will add discharge pressure for the start-up procedure.

Good Luck!