×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Atmospheric residue filter plugging

Atmospheric residue filter plugging

Atmospheric residue filter plugging

(OP)
In our ARDS unit, we encounter atmospheric residue filter(removing 25 micron particle) plugging problem for a long time.

The mesh size of suction strainer of the AR pump in CDU is 20. We wander if the opening the strainer is too large to remove the fine particle.

The ARDS filter plugging problem worsen during crude switch.

We guess some particle is carried with the crude oil entering the CDU, the particle then concentrate in the AR.

Who has the same experience with us?

How to solve the problem?



RE: Atmospheric residue filter plugging

What is the BS&W of the crude? It appears you do not have a desalter. A desalter will not only remove salts but also any sludge carried with the crude.

RE: Atmospheric residue filter plugging

Whenever you switch crudes the new inflows come from tank settled out bottoms with a potential dirt carry over. Is a multiple set of filters with some kind of backwash a working possibility ?

RE: Atmospheric residue filter plugging

(OP)
The BS&W of the crude is about 1%.

We have two stages desalter in CDU,
but no desalter in ARDS.

We have bag filter with 20 mesh in CDU
crude feed.

We have automatic backwash filter which
can remove 20 micron particle in ARDS.

 




RE: Atmospheric residue filter plugging

The BS&W is considered high. Sometimes double disalting helps. Sometimes pre-dilution of viscous crudes with lighter distillates help in settling. Others suggest the use of centrifuges or at least hydrocyclones. Water emulsions and oil viscosity are against efficient tank settling.

Anyhow, it wouldn't harm to contact Howe Baker e-mail: dking@chicagobridge.com
for electrostatic desalting, or Alfa Laval for decanter centrifuges.

The fact the AR filters plug up, indicates that the screen size is sufficiently small. Of course, it doesn't preclude smaller particles to pass through.

Is it possible you ask the supplier of the crude to take better care of his lot dispatches. Origin of sediment can be at the well by the use of drilling fluids (sand, clay, silt, shale or rock particles), or by picking up scale in transportation.

In the meantime try to use (install) a higher outlet nozzle in the crude feed tank, may be you can avoid a quick plug up of the filters.

RE: Atmospheric residue filter plugging

You have double desalting. Have you ever cleaned the desalters? How is the interface - clean or full of interface muck? This prevents proper water settling. This may occasionally get carried over during process upsets such as crude switch. Also the water carryover to the heaters can create a mild spalling of coke/carbon particles deposited in heaters. Do you see this effect ? This spalled particles can choke your filters. Have you analysed what is the strainer deposit? A high loss ibnition will corraborate this theory and a low figure will confirm what others have told you. Best of luck

RE: Atmospheric residue filter plugging

Looking at the problem a different way. Have you challenged the need for the filters being sized at 20┬Ám? In the offshore industry we've seen similar situations where inline filters have been over specified and through investigation have been removed or respecified to a higher size.

Just a thought!

RE: Atmospheric residue filter plugging

Another thought. Why not trap them in a regular Basket Filters ( twin duplex, sized to suit your cleaning schedule and with back wash facility) where it is convenient for you to trap them (if not possible in tanks or desalters)? May be that is what you are doing in yr ARDS filters.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login



News


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close