The feedstock and reactor effluent are passed through heat exchangers, with the feedstock flowing in the tube side and the reaction effluent flowing in the shell side – why?
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Why in some hydrogenation units is heat exchange between the feedstock and the reactor effluent carried out using a heat exchanger, with the feedstock flowing through the tube side and the reactor effluent flowing through the shell side? According to the principles for selecting tube and shell sides, should high temperatures be handled on the tube side?
It seems to be because of the high corrosiveness of the raw materials.
Normally, the effluent should flow through the tubes, while the raw material for heat exchange enters the shell side
Generally, the raw materials are in the shell side, while the reaction products are in the tube side. What kind of device is that in your place?
It might be related to the properties of your raw materials? Indeed, it’s the opposite of other devices
Not only temperature needs to be considered, but also comprehensive factors such as the cleanliness of the medium, its corrosiveness, and the type and design of the heat exchanger. It’s impossible to determine the specific reason, as the information provided by the original poster is too limited.
It is related to the properties of the material – it is toxic and corrosive – as well as to the procedures used in handling it
The raw material composition is quite complex, containing substances that tend to clog; when the heat exchange efficiency in the tube side is poor, it becomes easier to remove these clogging substances. :) Personal opinion
Generally, in high-exchange processes, the feed materials flow through the shell side while the reaction effluents flow through the tube side; the medium in the tube side is relatively clean and has low corrosivity； In some of these units, the high-pressure heat exchanger is of the coiled-tube type; to improve heat exchange efficiency, the reaction effluent flows through the shell side, while the feedstock flows through the tube side. There is no absolute classification for the media in the shell and tube sides; it is only relative, depending on how one makes choices. Just my personal opinion!
Our gasoline hydrogenation unit works in the same way
Generally, the product flows through the tube side while the raw material flows through the shell side. But it’s the other way around here. Is it because 1) the heat exchanger shell itself has expansion joints, or 2) the raw material is too dirty?