5 replies to this topic

[Eric Nguyen]

We have slurry separator ( gulftronic slurry separator ) because this system is not working well.
Ash spec in DCO is 100ppm but it doen't reach on-spec, DCO is on spec on somedays and off-spec the rest of month. Ash inlet slurry separator is about 4000 - 5000 ppm But Ash outlet slurry separator is alway higher than 100 ( about 200 - 300ppm). We tried to adjust operating parameter such as Increasing inletslurry temperature, reducing pause time, maximum voltage in order to make slurry separator work effectively but DCO was still off-spec and reached on-spec and then off-spec again. We are processing with high iron, Ca in feed, we mixed many crude oil from many sources ( about 5 kinds of crude oil) to get CCR: 3-4%, Fe + Ca < 12ppm. If anybody had experienced on this kinds of slurry separator, Pls kindly share your experience How to get back on spec with DCO or explain Why some time It hadn't worked well everytime we changed crude oil.

[Eric Nguyen]

Dear forum 

 

This post is our problem now and Ash in DCO is alway offspec and sometime it become onspec without reason. Is there any experienced refining man help me?We changed glassbead and increased slurry separator voltage to maximum but unsucessful.We think oil properties caused slurry seperator doesn't work well but don't know which oil property caused this problem? 

 

Best regards

[Killer Queen]

I think you have problem with fouling. Fouling is a very common issue at the units like FCC/RFCC or VBU, here the units often face the heavy fouling phenomenon. Fouling is not only coming from asphaltenes but from the ash + catalyst fines + asphaltens (Catalyst and coke interaction with asphaltene precipitation). You should check how much catalyst you are using per day, for example.

Edited by Killer Queen, 21 September 2013 - 11:21 PM.

[PingPong]

Without support from vendor Gulftronic you will probably not be able to figure out what the problem is.

 

First dig up the original design specification of the slurry separator and verify whether your present slurry throughput and its properties (resistivity, viscosity, inlet ash loading, density, moisture content) as well as the throughput and properties of the fluid used for backwashing are within the original design specification. If so then obviously the vendor has some explaining to do.

 

 

 

We changed glassbead and increased slurry separator voltage to maximum but unsucessful.We think oil properties caused slurry seperator doesn't work well but don't know which oil property caused this problem?

I have no experience with this kind of equipment, but if I had to guess, I would say that resistivity of slurry oil versus resistivity of the type/composition of beads you are using is a likely cause.

 

 

 

Why some time It hadn't worked well everytime we changed crude oil.

One guess: different crude oil source could produce slurry oil with different resistivity.

Another guess: presumably feed is used for backwashing, and as this feed is crude source dependent, its physical properties might affect effectiveness of backwashing operation.

Edited by PingPong, 22 September 2013 - 05:22 AM.

[GulftronicAce]

I just discovered this post. I apologize for not noticing it sooner.

 

I am the lead Field Engineer for the Gulftronic. I have been actively working with the refinery for the past couple months, and we have made many recommendations. I will be visiting this unit next week to assist in the troubleshooting/repair.

 

The 2 most common causes of an intermittent problem are: Valves and Module (the separation cell) internals.

 

The on/off valves are easy enough to troubleshoot. Each valve should be observed during the peration. When troubleshooting the valves it is important that each valve is fully closed, or fully open, at the appropriate time. Also the sequence of the valves should be observed. For example, the Backflush valves should be fully closed before the module is energized.

 

The Module is a little more tricky to troubleshoot, because it often requires a visual inspection. It is best to perform this inspection during shut-down/TA maintenance. An insulation resistance test can be performed quickly, and will usually help to indicate a problem within the module. The insulation test should be performed on the High Voltage Cable. First disconnect the cable from the High Voltage power supply then check for a ground fault. If there is a ground fault, then there is a problem with the high voltage cable, or the module internals.

 

For more Gulftronic information you can contact:

Sales: gulftronic.sales@ga-esi.com
Service: gulftronic.service@ga-esi.com

[Eric Nguyen]

Thank for your help

Recently, We approved to trial test with 3 slurry pump running parallel and Ash inlet was dropped significantly, Now It is about lower 2500ppm ( design: 3700max) , DCO is on spec about 1 month.I think the problem from catalyst fine acccumulated in slurry pump casing caused slurry separator overload when we started standby pump every 3day to avoid much catalyst fine in pump casing.We are closely monitoring slurry separatore performance..

 

Best regards