Multi product pipeline

[lhwingking]

I have a Pipeline through which HSD, SKO and MS are transported. The sequence of pumping goes like this.
HSD > SKO > MS > SKO > HSD > SKO > MS...

SKO is pumped for 2 reasons.
1. Requirement at the receipt terminal and
2. HSD and MS should not be mixed at any cost as their interface is a very big loss.

My question is, what will I have to do to pump HSD and MS alone if there is no requirement for SKO at the receipt terminal?

 

[BigInch]

You can't hardly build enough tanks when you consider interface generation losses. Wouldn't it be nice if design engineers and those that approve the budget knew that. I often think that this fact is only becomes known by the operations engineers.

IF you have another terminal farther downstream where SKO is needed.
Pump the sequence and strip off the MS and HSD volumes that you need as those batches pass the terminal. Close the stripping valve as the SKO batch passes the terminal.
ELSE----------------------
Pump MS/HSD with very large batches of gasoline, such that any interface generated can be blended back into the gasoline without any traceable HSD remains in the MS. (may require impractically large batches of gasoline. Do you have a lot of gasoline tanks?)
--------------------------
OR you might try using batching spheres, but I think you might not benefit very much from that.
ELSE --------------------------
Sometimes you just don't have an SKO market near the terminal, so
Deliver SKO anyway then truck it to the nearest airport.
ELSE ---------------------
Pump HSD/MS/HSD/MS as fast as possible to minimize interface generation.
AND----------------------
Sell any MS/HSD interface back to the refinery

I hate Windowz 8!!!!

 

[lhwingking]

Point 1: We are back to pumping SKO that has zero requirement. I will be wasting time and energy and I may not be able to meet HSD and MS demand at receipt terminal.

Point 2: You spoke my mind inside brackets. I do not have a lot of gasoline tanks. Even if I did have, refinery does not produce that much gasoline.

Point 3: Same reply as point 1.

Point 4: I am pumping these 3 products from the refinery and it wouldn't make sense pumping the HSD MS interface all the way back.

I think this will be a great challenge for us handling (avoiding) HSD MS interface.

 

[BigInch]

Zero demand for a product severely limits your opportunities.


I hate Windowz 8!!!!

 

[LittleInch]

lhwingking

Can you provide a bit more info on what your limits are for interface material and why your interface is such a big loss.

It's been a while since I was involved in multi product pipeline operations, but excess interface unable to be blended back in normally arose due to lots of batches in a short time or greater interface length due to low pressure, low flow, stop start / issues over the closure time of valves.

How many batches per month are you talking about? What is the volume of interface?, how much can you blend back into MS?

I agree with BI, that batching spheres etc are not normally any use other than marking where the middle of the interface is.

If you're pumping MS/HSD then you will get an interface, but there are some things you can do to minimise it.

Ultimately if you can't get rid of it truck it back to the refinery and sell it as crude.

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

 

[lhwingking]

Dear brothers,

Thanks for your responses and I appreciate your involvement in my query. But I wont be able to give you specific details as I am not directly related to that issue. I am a Pipeline Engineer (M. Tech Pipeline Engineering) in India working as a Piping Engineer in an EPC company for the past 1 year, totally new to hydrocarbon industry. During my college days I worked on an internship project in a company that transports HSD MS and SKO.

So my query was hypothetical. I am thinking what has to be done or what can be done if such a situation arises.

 

[LittleInch]

Pump continuously as fast as possible,
keep interface moving and pressurised,
use fast valves on the start switching manifold
Pump as large a batch as you can
Check to see what level of interface can be accepted in each product
Truck the rest back or sell it to someone to burn

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way