C4Reactor
Chemical
- Sep 29, 2001
- 21
Experiencing fouling at the tube side (Cooling Water) of a heat exchanger. The HX is of straight tubes with a longitudal baffle at the channel cover to allow for two passes design (TEMA type: BEP).
Cooling water enters thru the bottom nozzle of the channel cover, flow thru the tubes and return to exit at the top nozzle of the channel cover. Hot vapour enters from the shell top nozzle.
Fouling at the CW side observed at the top tubes only. CW flowrate registered at the inlet piping is above 1.8 m/s. At this rate the fouling is unexpected.
Understood that the relatively hot section at the top shell will lead to fouling in the top tubes. But a question to the group, for this type of HX:
1. Will the CW flow velocity in each of the tubes the same? Is it possible that the top tubes are having a lower flow velocity, due to the design, which further contributes to the deposition.
2. If we use a U-tubes design, will the occurance be the same?
Appreciate any comment
Cooling water enters thru the bottom nozzle of the channel cover, flow thru the tubes and return to exit at the top nozzle of the channel cover. Hot vapour enters from the shell top nozzle.
Fouling at the CW side observed at the top tubes only. CW flowrate registered at the inlet piping is above 1.8 m/s. At this rate the fouling is unexpected.
Understood that the relatively hot section at the top shell will lead to fouling in the top tubes. But a question to the group, for this type of HX:
1. Will the CW flow velocity in each of the tubes the same? Is it possible that the top tubes are having a lower flow velocity, due to the design, which further contributes to the deposition.
2. If we use a U-tubes design, will the occurance be the same?
Appreciate any comment
