Hot oil System

[asifraza0]

I am designing a tempered syltherm system. I've got three H-E in the network. Two of the H-E's are coolers in which sylthermm is heated from 100 deg C to 110 deg C. The third exchanger is a heater in which syltherm is cooled from 100 deg c to 90 deg C. I'm proposing a system in which syltherm is pumped through a heater (30 deg C to 200 deg C) and supplied to the users. Return from the users is returned back to the tank. Temperature is measured, if higher than 100 deg C, then passed thru' a water cooler to maintain the supply temp. Will this work ,Any suggestion from past experience.

Asif Raza

 

[TD2K]

If I understand you right, you go from a heater to your 3 parallel (don't know this, making a guess) heat exchangers (one of which is cooling the Slytherm and two are heating it) and then return the combined mixture to a tank and then the heater?

If you only need the inlet temperature to your three heat exchangers at 100C, why heat the Slytherm to 200C? Depending on the flows out of your three heat exchangers, the combined temperature will be somewhere between 90C and 110C, when then cool the combined stream all the way down to 30C to reheat it in the furnace?

Depending on the physical locations, flows and pressure drops of the various exchangers, you might be able to use the Slytherm that is heated in two of the three exchangers in the third one which would be more energy efficient.

 

[asifraza0]

Yes, the H-E' are arranged in parallel
My apologies, the syltherm will heated from 30 deg C to 100 deg C (During start-up).
Why cool the combined stream to 30 deg C, since it need to be reheated again up to 100 deg C.

Asif Raza

 

[25362]

Depending on the process characteristics, you may decide to put control valves downstream each unit to control flows and/or temperatures.

 

[asifraza0]

256362 & TD2K,

You noticed that there is a heater in the circuit which will cool syltherm to 90 deg C. Hence return temperature could be less than 100 deg C or more than 100 deg C depending upon the heat duty of different heat exchangers. I think there should be a cooler / Heater in the cicuit which will always maintain syltherm supply temperature to 100 deg C. Any suggetions?



Asif Raza

 

[pmover]

Asif,

it appears that there is some doubt on your part regarding the ho system design/operation. i highly recommend that you define/establish the process conditions; thus more reasonable "help" can be provided by other forum participants. guesswork will simply lead to a troubled ho system.

good luck!
-pmover

 

[25362]

In addition, include, please, the reasons for selecting that particular heat transfer fluid.

 

[MedicineEng]

I confess my confusion. You refer "heater" and then you say that it cools. You refer "cooler" and then it heats up.
We have one monofluid system installed and my experience is the following:
-It's quite convenient for production and doesn't allow errors/rpoblems like cooling water in the brine return line due to wrong operation/problems of the valves;
-It's very energy inneficient if you have big temperature requirements range (that is my case where it works from -20C till 120C.

I agree with the others. Think a bit more your system and then come back with some more solidified ideas. Like this is very difficult for us to give oppinion.