combined feed exchanger 1

[tarunchandel]

we have a combined feed exchanger to preheat the reactor feed and cool the reactor effluent it is single pass counterflow shell and tube heat excahngerit is not giving proper efficiency how can i increse the efficiency of the exchanger . the feed is hydrogen + (nC10-nC13) cut

 

[saxon]

tarun, If the flows haven't been increased through the exchanger, the problem is probably due to fouling. When was the last time the tubeside and shellside were cleaned?
If done recently, you may be able to help the situation by installing "turbulators" (tubeside static mixers), provided these don't impose too great a pressure drop.

Hope this helps.
saxon

 

[MOCHEM]

dear saxon
i have the same problem wth the sam exchanger,the exchanger is new and have a mixing nozzel to mix the hc with hydrogen.
i think that the problem with the over att heat transfer cof.calcolations,can you help me to check the exchanger calculations to fixe the exchanger problem.
thanks

 

[25362]

Depending on the degree of turbulence there may be phase segregation along the exchanger. From our experience: specially twisted fins on the hydrogen/liquid mix side have helped to solve a similar problem.