2 replies to this topic

[chemengstudent1996]

Hi, I am doing an esterification process in liquid phase. I am  planning to add heat to my packed bed reactor using a jacket with steam. However, I realized that the flow in my reactor is laminar with a reynold number of less than 10. This meant that my convective heat transfer coefficient in my reactor is around 9 W/mk which is very low. I calculate this value based on tube-side correlations . The typical value I found on the internet for convective heat transfer using steam jacket for liquid reaction around is 285-850 W/mk. May I know the reasons for such discrepancy in value? Is it because my reynold number is too low?

Edited by chemengstudent1996, 08 March 2021 - 07:13 PM.

[Pilesar]

I agree that your calculated heat transfer coefficient seems very low. Are you considering convective movement within the reactor due to temperature (density) differences caused by the heated wall? Steam will condense on the outside of the reactor if the temperature of the reactor is below the steam dewpoint. Where will that heat go? It may mean that steam jacket is not appropriate to increase the temperature of your system and would be useful only to maintain the fluid temperature. Consider whether internal steam coils or vessel agitation would make an appreciable improvement in heat transfer. How would your heat transfer change if you put the reactor inside a recirculating loop to increase fluid velocity? It would require larger equipment but might be a possible solution.

[breizh]

https://www.scienced...960852411016002

 

Hi,

Probably the kind of set up you should consider with an external loop. ( fig attached) .

you may consider thermal fluid instead of steam .Definitely more complex vs your proposal.

my 2 cents

Breizh

Edited by breizh, 09 March 2021 - 07:56 PM.