7 replies to this topic

[Rizalchoi87]

Hi all,

 

I have a scenario here which to design a heat exchanger to cool down ester product from 250degC to 170degC. The cooling medium will be hot water which inlet temperature is 90degC while outlet hot water temperature is 140degC (looks like become superheated water).

My question is how to maintain the liquid state of this hot water inside the heat exchanger. Otherwise it will become steam.

 

Hopefully anyone can help me.

 

Thank you.

[breizh]

Hi,

Can you use air to cool your stream instead of water ?

 

Hope this helps

Breizh

[Rizalchoi87]

Hi Breizh,

 

I am not sure how long it will takes to cool down my product if I use air. I decided to use hot water but unsure how to maintain the phase inside the heat exchanger (I mean what are instrument required to control it). Besides we have lots of hot water (from condensate) in our process plant.

 

Thanks,

Rizal

[Rizalchoi87]

Hi Breizh,

 

Do you ever heard about hot water raiser? Any idea on this? to convert hot water and become steam.

 

Thanks.

Rizal

[samayaraj]

If you are using hot water, the operating pressure at any point in the system should be above the saturation pressure for the corresponding operating temperature. For 140 Deg. C outlet, the saturation pressure is 3.615 Bar a. So, the hot water loop pressure should be Saturation pressure for max op temperature + Pressure drop in piping + pressure drop in Hx + margin.

Edited by samayaraj, 28 October 2015 - 03:12 AM.

[breizh]

hi ,

yes I've used  water under pressure to maintain temperature profile on batch reactors of resins and latexes . Not so simple to manage .Samayaraj gave you good pointer . you need to establish a loop of water at the relevant pressure and discharge hot water which is going to vaporize .

 

good luck.

 

 

Breizh

[latexman]

You raise the pressure with a pump.

[manojkaila]

Hi,

 

You can generate the steam & use in process with suitable steam generator with steam/water in shell side & process fluid in tube side. You can control the product temp by controlling the steam pressure.

 

Regards,