API plan for sour water pump
API plan for sour water pump
(OP)
Hello,
We are haing problems with single stage pumps that work with sour water (from crude oil desalators). Temperature: 120ºC
These pumps have single seal with flush plan 41, with cyclone separator and heat exchanger and the seals doesn't work properly as they leaking after few months. The flushing circulating doesn't seem to be good, as the temperatures doesn't follow a rational sequence.
I would be very grateful, if you had experience with this refinery service, if you could tell wich flush plan you use and your feelings about it.
I feel that plan 41 is not good and I would avouid the cyclone separator, as I do not have very good experience with this filtration element.
Any help will be greatly appreciated,
Marc
We are haing problems with single stage pumps that work with sour water (from crude oil desalators). Temperature: 120ºC
These pumps have single seal with flush plan 41, with cyclone separator and heat exchanger and the seals doesn't work properly as they leaking after few months. The flushing circulating doesn't seem to be good, as the temperatures doesn't follow a rational sequence.
I would be very grateful, if you had experience with this refinery service, if you could tell wich flush plan you use and your feelings about it.
I feel that plan 41 is not good and I would avouid the cyclone separator, as I do not have very good experience with this filtration element.
Any help will be greatly appreciated,
Marc





RE: API plan for sour water pump
Johnny Pellin
RE: API plan for sour water pump
I've not had a whole lot of experience with cyclone separators. They will wear out over time and they may need to be "tuned" so that the DP is enough to drive adequate flush to the seal. I do believe that they have a place in the world- especially in some older pumps that will not allow for larger cross section seals designed for slurry service.
JJ, 3 Crude Units? How many BPD?
I'm contracted to a refinery rated for 190 barrels/day.
RE: API plan for sour water pump
Johnny Pellin
RE: API plan for sour water pump
As you have said, the best solution would be to use a clean external source of flushing but at this moment we can't assume this modification.
What I've seen in this sela as good as other ones that work with an API plan 41 is that the flush doesn't flow in the right direction, sometimes going straight from the discharge to the suction and from the seal to the suction as well(passing through the exchanger and the cyclone). I feel that sometimes don't help and it's more a problem than a useful item.
I am not sure if it's possible to dismantle the cyclone in this service, because I feel that it's better to have fresh flush with enough flow rather than to have a very small flow not fresh(through the bushing).
Thank you so much for your considerations,
Marc
RE: API plan for sour water pump
There are other options available depending upon the solids content of the process fluid and the cross section of the seal chamber in your pump.
A rotating metal bellows can be used in some concentrations of solids. The bellows convolutions will "cut" through the solids and sling them away from the seal. There are also pusher seals available for higher solids concentrations. (I'd not suggest a single spring elastomer bellows in sour service- most of the elastomer bellows are offered in buna or fluoroelastomer- not my first choice for H2S) Several seal manufacturers have designs that will work in more than 20% solids- I'd suggest a tandem seal for process isolation and to help cool the inboard seal. Again, I suggest talking to your favorite vendor.
JJ- How is Jose doing? I'm his counterpart contracted to a refinery in St. Charles Parish, La. running mostly Venezualean, Mexican, and other inexpensive sour.