upstream crude offspec because of getting foamy 1

[msnsystem]

hi I'm working in upstream crude stabilization and desalination that specing h2s and salt.
recently we are getting offspec in both parameters because our crude nature becomes foamy and strange specially in our desalter sampling. all of our inlets are our crudes from our wells and a line named C5 from near petrochemical complex.
this happens batchly in every 10-15 days and the strange crude remains in desalter vessel for so long makes emulsions hard to break.
anybody have any idea? can our wells produce abrupt crude batchly and from unwanted reservoir layer? is it any petrochemical compounds that can make our cruse to become this way?

 

[georgeverghese]

Amines are well known as foam causing agents. Some one is perhaps injecting too much amine into the crude for piping corrosion management ?

 

[msnsystem]

the petrochemical operators telling us it only c5+ releasing from compressed gas were giving them. its posible there dumping something else but how are we gonna find out about it?
every liquid beeing pumped are storing in a vessel that batchly flows towars us every two or three days.

 

[georgeverghese]

Ask your Operations or Asset Manager to write a letter of complaint and call for a meeting. On the other hand, think it is likely these amine based corrosion inhibitors may be from one of your own wells.

 

[EdStainless]

It may be that there is a well (or group of wells) that are being chemically treated periodically.
And you are seeing a periodic burst of chemicals from that treatment.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube

 

[Lance T]

The major cause of foam in crude oil is the appearance of impurities, other than water, which are impractical to remove before the stream reaches the separator. Foam presents no problem within a separator if the internal design assures adequate time or sufficient coalescing surface for the foam to “break.” Foaming in a separating vessel is a three fold problem:

1. Mechanical control of liquid level is aggravated because any control device must deal with essentially three liquid phases instead of two.

2. Foam has a large volume-to-weight ratio. Therefore, it can occupy much of the vessel space that would otherwise be available in the liquid collecting or gravity settling sections.

3. In an uncontrolled foam bank, it becomes impossible to remove separated gas or degassed oil from the vessel without entraining some of the foamy material in either the liquid or gas outlets. Comparison of foaming tendencies of a known oil to a new one, about which no operational information is known, provides an understanding of the relative foam problem that may be expected with the new oil as weighed against the known oil. A related amount of adjustment can then be made in the design parameters, as compared to those found satisfactory for the known case.

It should be noted that the amount of foam is dependent on the pressure drop to which the inlet liquid is subjected, as well as the characteristics of the liquid at separator conditions. In some cases, the effect of temperature may be significant.

Foam depressants often will do a good job in increasing the capacity of a given separator. However, in sizing a separator to handle a particular crude, the use of an effective depressant should not be assumed because characteristics of the crude and of the foam may change during the life of the field. Also, the cost of foam depressants for high rate production may be prohibitive. Sufficient capacity should be provided in the separator to handle the anticipated production without use of a foam depressant or inhibitor. Once placed in operation, a foam depressant may allow more throughput than the design capacity.

Link