Sludge Oil Disposal

[tomatge]

I was talking recently to a power utility in a developing country, who have built up a major problem with sludge oil residue from burning heavy fuel oil in slow speed diesel engines. Without anything else to do with the stuff, they've simply stored it up in a bulk fuel tank.

They now have nearly 4000 tonnes !!

Any ideas as to how this can be disposed of in an environmentally friendly way, AT MINIMAL COST. It's no good talking about fluidised bed combustors or the like, this utility struggles to buy its basic fuel.

We operate similar plant, but simply pay somebody to take the stuff away. This is not an option here.

 

[op9]

When you say sludge oil residue are you referring to what is removed from centrifugal fuel separators and purifiers, or what may be collected out of scavenge spaces, or both.

Generally this can be disposed of through special sludge burners, BUT the secret is to first remove as much of the free water by draining, and then ensuring a homogenous mix of the remaining emulsified sludge and water. Preheating will be required. Again depending on the final state of the oil and how much water is still present, another auxilliary burner, or pilot flame may/ is probably required (using good fuel. Basically you are incinerating the sludge, but again depending on its "quality" some useful heat may be recoverable.

With more information I may be able to assist you/ your customer with a suitable system.

Rod Nissen.
Combustion & Engineering Diagnostics
canded@iprimus.com.au

http://www.canded.com.au

 

[subhuman]

there is a company called United Energy. THey make a compound which makes the oil sludge liquify, and can still be processed later. I think they have a website running now, but do not know the address. Might be worth looking into for your application.

 

[joshterp]

I also work at a Utility site in the US where they used to burn No. 6 F.O. normally. There was a significant quantitiy of bottoms which we recycled if it met certain criteria. Some material went for an ashpalt recycling plant. I think the name of the company was Envirocycle in Bakersfield, CA, US.

Josh
joshterp@aol.com

 

[tomatge]

Thanks for the answers to date.

op9 ... there is a mixture of sludge from scavenge drains and from centifuge waste product. Probably also a certain amount of HFO (spillages etc.). As you point out, doubtless a significant quantity of this is water, but with the sludge stored in a non-heated tank separation is not too effective.

The only way I can think of disposing of this is to burn it, possibly using auxiliary fired boiler. The problem remains that the utility does not have such plant, and has no money to buy one.

 

[op9]

Without any way to purchase new equipment they appear to be in a no win predicament unless there is some means of seeking overseas aid??

Obviously the generation of this waste will be an ongoing situation. Some years ago (20) when I was at sea one of our vessels tried out a system where they did away with the fuel centrifugal separators and instead used a homogeniser to "homogenise" the fuel and water and sludge (as bunkered)before supplying it directly to the 2 stroke large bore engines. (In this particular case they were the opposed type Doxford). As far as I am aware, after some initial teething probs it was quite successful. This then reduces significantly the waste generated. The company that supplied the homogeniser was British, but I cannot say if this is still a currently used technology?? Maybe some presently serving Engineers will know or have heard of it?

What make are the engines? Maybe the manufacturer may have knowledge of this type of system and whether it is "recommended".

Regarding heating the sludge, how do they now preheat the main engine fuel, electric or steam?

See how you go. Regards,
Rod Nissen.
Combustion & Engineering Diagnostics
canded@iprimus.com.au

http://www.canded.com.au

 

[jmw]

I had heard that the sludge is burnt with the fuel using a fuel mill to reduce it. Probably the same as the homogeniser.
S.I.T. might be able to help (they produce fuel water emulsification equipment i think)

 

[jmw]

Visit this site for a report on sludge, causes, effects, etc.

http://www.bre.com/technicalpapers/technicalpaper.asp?articlenumber=33