I've been asked to look into different ways to remove water from up to 10000 liter batches of oil. About every 2 weeks ongoing. Last analysis showed about 15000ppm water. Need to fix source of water but until then?
I think either Alfa Laval type separators or Hydac type vacuum dehydrators are 2 good options? Better sugestions are welcome.
May I have some comments about the differences between the two, price wise, performance wise, good used equipment availability and location. Maybe renting is a good alternative?
Thank you.

Mikoil,
Both the systems have pluses and minuses
Centrifugal system is good for removal of free water especially when the quantity of water is very high.
The advantage of Vacuum dehydration is the capability to remove dissolved water, but the process is comparitively slow
The dehydration system selection depends on your requirement.

Few points to remember

If you can prevent the entry of water into the system, that will be the best solution.

Presence detergent aditives retard water seperation.

Water seperation ability depends on the type of base stock

Water can deplete additives, destroys lubrication properties, enhance rust / corrosion, acclerate oil deterioration, reduce filter ability, forms gluey mass, cause cavitation and leads to Hydrogen induced Embrittlement.

Mikoil,I'm not a filtration expert, but most oils separate readily from water, improved if warm. If possible allowing the oil to stand will allow a large proportion of the water to settle in the tank, which can be removed by draining off, the remaining water can then be removed by the recommended means.

Mikoil,

I have had some experience with the PALL Portable Purifier Unit HNP021 series. It is a portable vacuum dehydrator designed to remove free and dissolved water. From memory, it took out upto 80% of the water and as much as 45L water a day.
It was used to remove water in a steam turbine application. The water content was at 12000ppm and held 22000L. Initially, as much of the free water was removed from the resevoir tank by cracking the dewatering tap on a daily basis prior to using the purifier.
The unit also came intact with 2 X 3 micron filters which also had water absorbing qualities so the oil was kidney looped after the vacuum dehydration process.
The vacuum dehydrator and kidney looping worked really well - the water content down to 117ppm.
You can hire them on a per day rate - not sure who are your major filter companies in Canada. It's pretty expensive to buy the unit. You will also need to pay for consumables such as the filters. Also may be a bit of working out the connections etc.. - but the filter company can help.
I am not sure what sort of application or oil type you are using it in. It's best to get the oil tested first in it's poor condition and speak to the oil supplier to see if any of it's properties or additives are already affected by the water to work out if it's a worthwhile process to go through ie cost of unit hire + consumables VS cost of new oil or if oil is too far gone.
Once the water is removed, retest again and speak to the oil supplier about the results to gauge if any of the oil's properties are still affected.
Also some of the CC Jensen filters have coalescing elements for water with the portable kidney loop units and can hold upto 3L of water each or so but you will need to check which ones.
I hope this helps.

Thank you everyone,
We have tried to see if the water settled out in a clear container and let sit for 3 or 4 days. Nothing noticable appeared on bottom. Is it better to do try it in very cold area or very warm area? I think cold but not sure. We also are trying a by-pass absorbant filter, portable unit. so far a 50% water reduction, now at 8000 ppm. Maybe more filter changes. We are trying to work out a process that will work everytime a batch needs to be decontaminated. Still thinking about vacuum dehydrator. Any more suggestions? Lab says properties and wear metals are stable up to this point. Oil is a draw oil of a couple types, sometimes slightly mixed but acceptable for the application. Production parts are comming out to quality spec. which is the important thing.

Hello.

With such water levels you should be aware of microbacterial contamination.

I have only good experiences with vacuum dehydration for high water levels. Just couple it on and let it work continious.

Dear Mink,

You do not say the viscosity of the oil, therefore water separating is hard to determine. Usually water will separate better when Hot. Alfa Laval seperator usually wants 120 to 150 Deg F temperature to work well.

Please tell us more about the oil. Typr, viscosity, contaminants, etc.

The old Bowser type separators work well for turbine oils, but we need more info.

at these levels of water maybe a coalescer would be a cost effective option, however if the oil is dirty it could cost a fortune in cartridges.