oil recycing

[tomberwick]

With the price of oil on the up and up I am considering recycling the oil which I drain from my ammonia plant. I use Howden screws with the usual carry over problems, however the the oil I drain from both intercooler and surge drum is relatively clean and I believe could be reused after a bit of filtration and purification. I have not been able to locate a UK supplier of such a filtration plant, does anyone know of a UK manufacturer / supplier?

[Magoo]

Why not build your own, years ago I work for a meat works company that had megawatt low temp refrigeration, rows of Howden screws , big Howden screws, It was my job once a week to clean up all the oil drained from the multistage system.
First send all oil through a centrifuge separator [ like a dairy separator ] to remove any water, next was to fit drum heaters to waste, then pump through a series of paper filters. After several passes and lots of filter changes the oil was like new. They stored the oil with a drum heater on each drum, heaters kept oil at about +30'C. This cut there new oil requirements to a fraction.

[Josip]

Hi, Magoo :)


Why not build your own, years ago I work for a meat works company that had megawatt low temp refrigeration, rows of Howden screws , big Howden screws, It was my job once a week to clean up all the oil drained from the multistage system.
First send all oil through a centrifuge separator [ like a dairy separator ] to remove any water, next was to fit drum heaters to waste, then pump through a series of paper filters. After several passes and lots of filter changes the oil was like new. They stored the oil with a drum heater on each drum, heaters kept oil at about +30'C. This cut there new oil requirements to a fraction.

What about to send a sample of purified oil to original manufacturer for final check? To confirm, is it OK for reuse.

I'm not sure we can use oil "forever", but maybe I'm wrong!?!

Finally, purification was not free of charge ... installation/manufacture of purification station, use of "lots of paper" filters, electrical heaters to keep the oil at +30*C, your work ... etc... you've got a "clean" oil but maybe not with all ingredients as a new one ...

not sure, but very much "invisible" expenses gave some feeling of savings ...

I hope some other members will post their opinion/s just for discussion...

Best regards, Josip :)

[glenn1340]

Not to sure about sending the sample of old oil to the original manufacturer as they`d just to sell you more new stuff.
An independent oil analysis service is the best bet. They`d need a new sample of the original oil as a comparison. The place we use costs about £30 for that you get a complete report of its condition ie wear metals, TAN, moisture, silcone levels and lots more.

[RANGER1]

Tomberwick
We have had clients in the past do the same as Magoo mentions.
I was always sceptical as you don't put re-used oil in a Roll Royce do you?

It seemed to work OK but at the same time older large plants through over 100 litres a week
so it can be justified to do it.
More clients these days are using synthetic oil so at @ $20.00 a litre its very expensive.

Its easy to buy say a 3 micron oil filter to clean it but the moisture is a bit harder to get out .
ie centrifuge, heating.

The main thing affected could be viscosity of oil , but what are you going to do about it
if its to low after you spend X amount to get it tested?

In or region until a few yrs ago there was an oil laundering service that did it for you &
put it back into specification,maybe thats worth investigating in your area as it should be cheaper.

How much oil is your plant using & what type of oil is it?

Does you oil seperators have coalescers that could be replaced or are they a sealed vessel?

[Magoo]

Hi Yosip
This place drained hundreds of gallons a week, but still added new oil into system. A sample of each batch was tested in the on site laboratory, check the water content and viscosity and purity. They had about ten of the biggest Howdens I have ever seen, plus rows of Hall 5 x 4's

[Josip]

Hi, Magoo :)


Hi Yosip
This place drained hundreds of gallons a week, but still added new oil into system. A sample of each batch was tested in the on site laboratory, check the water content and viscosity and purity. They had about ten of the biggest Howdens I have ever seen, plus rows of Hall 5 x 4's

OK, I see where you were ..... ocean of drained oil to clean .... kind a Sisyphus job;)

What to say, for me something is not good with plant oil system .... oil separators probably are not designed well and not working well, wrong type of oil, etc ...


Best regards, Josip :)

[Magoo]

Josip.
The plant was multi megawatt, three stage. The system moved mega cubic metres of ammonia per second. From memory the high stage suction was 36 ish inch, dual suction and cross overs everywhere.
Frightening stuff for a young bloke in those days. Most coelesars will carry over a minimmal amount, multiply that minimal amount by huge mega watt plant the draining from system was large. Basically one person's full time work draining oil from everywhere, from low temp accumulators, droppers on interstage system, you name it is was drained to maintain max efficiency of total system.
.

[McFranklin]

Don't do that. We had a customer that recycled their oil, it significantly reduced the service life of their compressors. Part of the problem is that the oil has additives and conditioners, each brand has different levels and combinations of these.
One of the additives is to inhibit corrosion, another reduces sludge formation, and so on. These additives are used up through the life of the oil. I sent some oil samples to the lab Frick uses, one set was a non Frick brand oil. They analyzed it but noted on the report that it was not a Frick lubricant and that we should have the values reviewed. Yes, they want to sell their brand of oil, I am fairly certain that most if not all the manufacturers sell a "house brand" of oil. As do many of the contractors. (The company I work for has at least four different types).
Just go to an oil supplier's web site and read their advertising.
And that customer had over twenty compressors rebuild and only a couple of them didn't need extra work on the rotor bearing surfaces.

[tomberwick]

Well thanks for the input chaps.. but I still don't know what road to go.
If I build my own machine and the screws start to throw the towel in prematurely, I'll be out of a job.!!
I have 5 compressors, all Howden screws, 2 x Howden 255wrv's on line at all times, and drain off around 30 litres a week, I do have a coalescing element as well as the usual oil separators, and I don't think my carry-over is unusually execessive, but at the cost around £2.00 Per litre for Shell FRA oil. = £60.00 per week or £3000.00 per annum, plus of course I need to do a full oil change on occasion, which takes us up to an average spend of around £4000.00 a year. If I could source a Commercially built and fully tested and accredited recycling machine for a cost of around £5000.00 (which I could source in the far East) then this would be a no brainer. My original question was -- does anyone know of a UK Manufacturer/Supplier

[aawood1]

Hi tomberwick,
It was only three weeks ago I was talking to Grasso about the amount of oil we are draining from the Grasso SP2 pack system we had for last new install on this site Dec.2010, They said that have installed a filtering system on some other plants now within the UK to return the oil from the receiver and interstage drum. But at this time I have not had any feed back and before I move forward with this a site visit to one or more of the sites where it's been fitted would be a good called for. As we remove around 180 lts every 21 days when we shut down. If I find out anymore I will feed it back.
Arthur.