Series connection of filters: new problems for veteran revolutionaries
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Unqualified products from the reactor outlet are sent back through a reflux line: first a precision filter, then a sight glass, followed by a Y-filter, then a pump, and finally back to the reactor. Is the Y-filter necessary?
The thicker ones should be placed first, followed by the thinner ones. Too much can lead to high resistance. It runs stably; as long as it’s easy to clean.
The information provided by the poster is limited. What type of pump is it? Centrifugal pumps definitely won’t work; with this setup, it’s easy to end up with insufficient suction by the pump, resulting in idling. Although positive displacement pumps can idle, this type of piping connection is also not recommended. Why not install a Y-filter at the pump inlet and a precision filter at the pump outlet? Then, samples of the fluid coming out can be analyzed – if they meet the standards, they can be collected, while those that don’t meet the standards can be sent back to the reactor
The documentation is incomplete; the type of pump is not specified in the equipment list. However, it’s a circulation pump, with low head pressure – generally, such pumps are centrifugal pumps.
It seems that the project is still in the design stage and has not been implemented yet. Personally, I suggest that if precise filtration really needs to take place at the pump inlet, then a buffer tank should be added between the pump inlet and the precision filter. The liquid level in this tank can be linked to the pump; the pump should stop operating when the liquid level drops to a very low level, thereby ensuring proper operation of the pump. Another question: Is nitrogen being used in the pipes and precision filter for purging, to maintain pressure, or to protect the system? If it is due to material compression, it indicates that the viscosity of the material is high; in such cases, it is even less reasonable to install a filter at the inlet of this pump.
For precision filters, nitrogen should be used for back-purging.
If fine filtration is used, a filter is not necessary; however, if the fine filtration is placed after the pump, a Y-filter needs to be installed before the pump； Furthermore, it is not recommended to install a precision filter before the pump, as this often results in an insufficient net positive suction head.
:These two filters are not the same at all; one is used to filter out insoluble substances, while the other serves to protect the pump. The former will definitely meet the requirements of the operating conditions, whereas the latter is a protective measure
I know, but fine filters often have high resistance; melt-blown filter elements or metal-sintered filter elements are used in such cases.
:I took a close look; it’s called a refined kettle filter, not a precision filter. . .
The first filter is used to filter the solid catalyst particles inside the reaction vessel； The second Y-type filter is a standard filter for centrifugal pumps, used to protect the pump ； There’s nothing wrong with this design