Condition 4 is the ideal / desired condition for any TF system, where in the thermal cracking takes place due to aging of TF after long duration (many many years) of use and will be indicated by only flash point reduction & lowering of viscosity value of the system TF. This is due to more % of low boilers presence in TF after a long use. Only by replacing some volume of
old TF with the fresh TF (10 to 30 %, or as per the % low boilers the old TF) will replenish the properties of the old TF for further continued use.
Regular Thermic fluid analysis (quarterly) can indicate the health the system, in a much similar way as our blood tests indicate health of our body.
As stated above, the final result of the thermic fluid degradation (conditions 1 to 3) is generally indicated by rise in viscosity & viscosity index (change in viscosity with change in temperature).
So the degraded thermic fluid gets thicker, which results in to lower TF flow through the heaters which in turn gets over heated (Carbon formation / Increase Of Insoluble % in Benzene/hexane/Acetone >1 %) in the heater again, results into further degradation /lowering of viscosity .This chain reaction is fast & makes the final stage to highly viscous, un flow able, jelly or tar like appearance of TF at normal temperature. Such condition of TF requires continued heating to keep it in flow able condition & can be partially drained out of the system in hot condition only.
Such TF condition demands immediate complete draining/flushing out & refilling the whole system with new thermic fluid. But the system may have blockages and it is a very tedious, time consuming task to clean the complete system. In spite of all efforts the internal surfaces of the pipe lines, heat exchanger, heater tubes may retain the large quantities of old contaminated fluid & its sticky layers deposited on all internal surfaces of the system, will again contaminate new thermic fluid.
A long forced system shut down may be required resulting into loss of production & financial losses.
As you know use of any water based cleaning agents are not at all recommended as these are ineffective to remove hard carbon / sludge deposits. Moreover, the remaining traces of the water in the system bound to get mixed with the new fluid. This happens in most of the cases and creates havoc during system re commissioning. This leads to excessive TF overflows through the expansion tank, build up of excessive pressure in TF system more than system design pressure and may lead to busting or leakage through pipe/flange joints, causing sever fire /burn injuries. Also severe vapour locks & resulting low flow conditions due to water vapour in the system may over heat the new fluids & can contaminate the new TF.
To tackle this conditions M/s Shreyas Petroleum Additives Ltd ,an Ahmadabad based company, who are into manufacturing of a wide range of SigmaTHERM brand of premium thermic fluids & additives , have developed a unique thermic fluid system 'Cleaning Additive & Life Enhancer Fluid' SigmaTHERM FF 101.
Based on the condition of the existing contaminated thermic fluid (indicated by the latest analysis report) SigmaTHERM FF 101 is added (max up to 20% of total system volume) into the old degraded operating TF system, in cold or moderately hot flow able condition (for highly viscous fluids)
Only up to 20% of the total system volume of SigmaTHERM FF101 is added by draining our same quantity of old fluid. The mix is circulated, heated & operated up to 240 deg C for at least 50 hours.
It’s amazing & powerful action provides a dramatic reduction in the viscosity of the contaminated fluids while solubilising any hydrocarbon oligomeric sludge and deposits in heat transfer systems
SigmaTHERM FF101 additive exhibits exceptional solvency for the hydrocarbon structures found in most petroleum heat transfer oils and synthetic organic heat transfer fluids.
Its low viscosity & pour point, relatively high boiling point and superior thermal stability makes SigmaTHERM FF 101 ideal for the use with thermic fluids particularly when they are thermally & oxidatively degraded .
Unique Advantages of SigmaTHERM FF101 : 1. Very economical solution requires only 20% maximum addition of the total system TF volume.