Pipeline Start-up Problem

[MTQ80]

I need some urgent help on below problem.

One crude 100km,36in pipeline is design to handle 500MBOD flwo rate with line pressure drop of 224psi. At start up line there is centrifugal pump with no discharge control valve delivering 270psig required inlet pressure. At the moment problem is how to start the line and to run line for couple of months at low flow of 150MBOD as pipeline is not offering required resistance and there is no back pressure control valve at end of pipeline. So how to start and run lien at low flow.

 

[gerhardl]

Regulate by controlling pump speed/output?

 

[MTQ80]

Pump is fixed speed and pump is delivering pressure at low flow but pipe line is not seeing that pressue as no back pressure in line and large size of line very less pressure drop in line at low flow.

 

[insult2injury]

There probably isn't a solution that cost 0 dollars if that's what you are looking for.

I2I

 

[MTQ80]

cost is secondary thing, we looking for some sort of temporary as well as permanent solutions.

 

[owg]

1)Fill the line with oil either by using a temporary lower capacity pump at the upstream end, or by backing oil "up" the line from the downstream location. Take the normal safety precautions, don't mix oil with air. You don't say whether the line was turned over to you full of water, air, something else? If it was just hydrotested it should be full of water in which case you don't have a problem.
2)Run the pipeline pump under design conditions but only run it part time (about a third of the time).

HAZOP at

http://www.curryhydrocarbons.ca

 

[lizking]

install temporary orifice between flanges.

 

[Bala0610]

Hi

Maybe I'm missing something..do u have a problem with the motor current(pump operating at end of curve without resistance...)? Lizking has the solution for you...this route is often followed to "match" pump to required system head...This would be inefficient though (as u'd kill a lot of pressure across the orifice on discharge). OWG's solution is good, if u can afford to hold on to oil at source for 16 hrs, while pumping for 8hrs...I'd be curious to know what u do...!

 

[BigInch]

Do I take it that you have no valves in 100 km of pipeline???

"Make everything as simple as possible, but not simpler." - Albert Einstein (1879-1955)
***************

http://virtualpipeline.spaces.live.com/

 

[katmar]

MTQ80, what is your role in this problem? If you are the client, then just throw it back at the designers or consultants. If you are the designer then run like hell. Or is this a homework problem?

 

[owg]

lizking's suggestion to install an orifice plate would allow steady operation at the required throughput, and avoid the stop/start operation that I suggested. Hopefully there is enough flexibility to accomodate an orifice.

HAZOP at

http://www.curryhydrocarbons.ca

 

[RPilch]

Why not put a bypass line around the pump. You can inventory the discharge pipeline without running the pump. You may even be able to get the lower flow you want without running the pump. You should be able to figure this out from the design conditions for the pipeline and pump.

 

[786392]

1)If the mechanical works permissible,
line is Gas-free(No flammables/Combustibles inside)and
Cost(as indicated) no problem;then have Throttling Valve with flanges installed at begining of pipeline closed to the pump outlet.
Hope this may be helping.

Best Regards
Qalander(Chem)