Sedimentation (Fuel Oil)

[jagfrediani]

Hello everybody:

I'm making a project in a cement factory and i would like you to help me find some information...

We have a rotary kiln that burns about 53gal/min of Fuel Oil N6, it has a relative density of 0,983 (@15,6ºC) and a kinematic viscosity of 416 cSt (@50ºC). All the Fuel is stored in two tanks of 5500 m3... Near to those tanks we have some heater exchangers to get a lower viscosity and then pump the Fuel Oil to the kiln, THE PROBLEM IS that lately we have been receiving the fuel with a high degree of contamination (silica and other kind of particles) and our present filter system can't prevent clogging of heat exchangers because of the dirt.

The very first idea is to work on the filter systems, but also i have to evaluate the possibility of making a sedimentation tank, i want to know how much time the Fuel has to be steady so the particles and even the water get to the bottom of the tank...

I've found a lot of papers of sedimentation but working with water, i need information about sedimentation in Heavy Fuel Oil... How and where can i get that information?

Any comment, any suggestion is welcome... thanks in advance

 

[BigInch]

24 hours is a typical minimum time for very much lighter products, so that is not going to be anywhwere near enough time to clarify a heavy fuel oil. I'd guess you'd need at least 5 times the tankage to have any hope of settling anything worthwhile out of it, maybe 10 times. You might have better luck looking for higher quality oil than fitting all those tanks into your plot plan.

"I am sure it can be done. I've seen it on the internet." BigInch's favorite client.

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http://www.youtube.com/watch?v=hpiIWMWWVco

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[jagfrediani]

Hello BigInch's, thanks for your comment...

Unfortunately to change our fuel supplier is not an option... What i need is to prove that a sedimention tank is not the best idea to solve our problem, but i would like to have some bibliography or some reserch so i can say that properly... Basically only would need that "sedimentaton time" to estimate the size of the tank...

Do you know where can i found that?

Thanks again

 

[BigInch]

With that heavy viscosity, settlement time is going to be a problem. I don't have any docs with the info already developed, but you could easily calculate the theoretical settlement time, if you know the average size and density of your particles. Search for "Stokes settlement velocity" and you will find a method for estimating the time it will take for those particles to drop out of the oil. I'd be interested to know what you find out and if my 10X estimate is reasonable, or if its still higher than that. I wouldn't be surprized if it was.

"I am sure it can be done. I've seen it on the internet." BigInch's favorite client.

"Being GREEN isn't easy." Kermit

http://www.youtube.com/watch?v=hpiIWMWWVco

http://virtualpipeline.spaces.live.com