Can anyone suggest a possible cost effective method/process for lowering TAN in used hydraulic oil in stored bulk quantity of approx 1000 ltr at a time (as an example), oh and please don't shoot me, this is my first post.
Original Post
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First just wanting to double check and make sure this is a virgin oil bulk tank?
Hi Lubes and thank you for the reply.
Using the following example ...
the oil is used mobil DTE series Hydraulic oil, which I believe has a start tan of approx 1.2,
colour appears ok,
moisture has been removed by way of vac dehyd. down to 60 ppm (can go further)
tan reported after dehyd was 1.63, we did not test start tan,
oil filtered through mpg down to very acceptable levels.
I have designed and built a vac dehyd focusing on moisture removal and it works very well but the problem often faced is elevated tan, the above is one batch that was treated where we considered the tan too high to put the oil back into service.
Is the vac dehyd unit capable of reducing tan ?, this I do not know and have not as yet done testing to confirm or deny.
Whilst I accept that there are other parameters that will effect a decision as to whether the oil could be put back into service, it is the tan at this point that is holding us up.
Any idea's ?
Using the following example ...
the oil is used mobil DTE series Hydraulic oil, which I believe has a start tan of approx 1.2,
colour appears ok,
moisture has been removed by way of vac dehyd. down to 60 ppm (can go further)
tan reported after dehyd was 1.63, we did not test start tan,
oil filtered through mpg down to very acceptable levels.
I have designed and built a vac dehyd focusing on moisture removal and it works very well but the problem often faced is elevated tan, the above is one batch that was treated where we considered the tan too high to put the oil back into service.
Is the vac dehyd unit capable of reducing tan ?, this I do not know and have not as yet done testing to confirm or deny.
Whilst I accept that there are other parameters that will effect a decision as to whether the oil could be put back into service, it is the tan at this point that is holding us up.
Any idea's ?
TAN is an indiction that your oil oxidised to some extent and become corrosive ,this process is achemical change so it is not reversable
I understand TAN to be an indication of oil condition, and ageing. Water contributes to accelerated oil ageing, and so increased TAN levels. So I guess that by removing water, the TAN will change.
Having said all this, I don't profess to be an expert either
Having said all this, I don't profess to be an expert either
Thanks all ... the new oil tan for this product is typical 1.2 so I considered 1.63 being too high for it to remain in service but then i set about looking for ways to reduce tan just to see if it was possible, have not found one yet.
Water causes oxidation and acids but removing water does not generally reduce the tan (sorry matt), I have been "playing" with vac dehyd for some time now and have noticed at times a slight reduction in tan but have not done any specific testing to prove or disprove the reduction was due to vac dehyd.
I have dried very wet oil down to 8 ppm with no reduction in tan and have dried other batches with a slight reduction but observations are by no means definitive at this point.
I suspect that some acids may (only may) be affected by vac dehyd and others not, but that is as far as i have got and i am by no means a chemist.
I have also tried fullers earth and alum sulphate with little or no result even though the medium manufacturers quoted them being able to reduce tan.
My machine is commercially viable (extremely efficient) at reducing water, the filtration will clean down to acceptable iso clean (not hard, anyone can do that)and if i could find a way of reducing tan that would top it all off, improving colour would be another process that would prove very valuable.
My thoughts have shifted to additives that may reduce the tan (calcium sulphonate for eg)but again i am no chemist.
Any thoughts/help regarding reducing tan and or improving colour would be very much appreciated.
I am not hear to sell my machine or services and am so pleased to have found this site, it has helped me in many other area's already, just from reading the many posts.
thanks all
Water causes oxidation and acids but removing water does not generally reduce the tan (sorry matt), I have been "playing" with vac dehyd for some time now and have noticed at times a slight reduction in tan but have not done any specific testing to prove or disprove the reduction was due to vac dehyd.
I have dried very wet oil down to 8 ppm with no reduction in tan and have dried other batches with a slight reduction but observations are by no means definitive at this point.
I suspect that some acids may (only may) be affected by vac dehyd and others not, but that is as far as i have got and i am by no means a chemist.
I have also tried fullers earth and alum sulphate with little or no result even though the medium manufacturers quoted them being able to reduce tan.
My machine is commercially viable (extremely efficient) at reducing water, the filtration will clean down to acceptable iso clean (not hard, anyone can do that)and if i could find a way of reducing tan that would top it all off, improving colour would be another process that would prove very valuable.
My thoughts have shifted to additives that may reduce the tan (calcium sulphonate for eg)but again i am no chemist.
Any thoughts/help regarding reducing tan and or improving colour would be very much appreciated.
I am not hear to sell my machine or services and am so pleased to have found this site, it has helped me in many other area's already, just from reading the many posts.
thanks all
TAN is defined as the amount of acid and acid-like material in the oil. Oxidation and nitration resins make up the majority of this material. As the oil is used, acidic components build up in the lubricant causing the TAN number to increase. A high TAN number represents the potential for accelerated rust, corrosion and oxidation and is a signal that the oil should be replaced. Critical TAN numbers are dependant on oil type. Typically R&O and light duty oils have a maximum TAN of 2 while anti-wear and EP oils may have maximum levels of 3 to 4.
Regards,
Dave
Regards,
Dave
I think it would pay to consult the oil supplier prior to adding any additives to the oil. The addition of additives not intended for this particular oil may void any OEM requirements and change industry specifications that the oil was designed to meet.
Fullers Earth or Activated Alumina Cartridges to neutralise acid and lower TAN
http://www.oilfiltrationsystem...w_filtration_systems.
Frank
http://www.oilfiltrationsystem...w_filtration_systems.
Frank
