Problems with the vacuum tower bottom pump
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May I ask: Is there a filter designed or used at the inlet of the vacuum tower bottom pump? If so, what specification type should the filter be? Current situation: Coking occurs at the bottom of the vacuum distillation tower, and there is no filter at the pump inlet, which allows these coking particles to enter the pump and block the flow channels of the impeller. This results in poor pumping performance, requires frequent cleaning of the impeller to remove the coking, and affects the processing capacity of the plant. Feel free to share your thoughts: 1. Since the inlet of the bottom pump in a vacuum distillation tower is usually under negative pressure, could a filter easily lead to insufficient flow at the pump inlet? 2. Can the pump at the bottom of the vacuum tower be replaced with a semi-open impeller centrifugal pump to throw the coke lumps into the pump outlet filter?
There is generally no filter at the bottom of the vacuum distillation tower, but it can be installed through technical modifications.
The inlet of the vacuum tower bottom pump is generally under negative pressure. The key question is: if a filter is installed, could slight blockage lead to insufficient flow at the pump inlet? Is there any other affiliated unit using it?
I have two filters installed at the bottom of the vacuum tower; normally only one is used, but later I decided to use both of them, and there were no issues with flow restrictions. It’s important to ensure that the flange seals of the filters are proper. As for the second issue, I’ve never seen this type of pump used before.
If any pump inlet filter becomes clogged, it will result in insufficient flow at the pump inlet; the key is to clean the filter promptly.
If coking is severe, it should be installed. Filter screens are generally installed at the inlet of water pumps; therefore, I think a filter screen is sufficient for the pump at the bottom of the pressure reduction tower.
It seems unnecessary, right? Since a clogged inlet filter can lead to insufficient pumping volume, we did not install one in our device.
We have T-type filters, and they work very well. Our washing oil pump originally had a closed impeller, which often caused blockages in the flow channels; after switching to an open impeller, the problem was resolved effectively. It has never been clogged.
The pumps at the bottom of the tower are all equipped with filters, and they have never become clogged; no coking occurs at the outlet of the vacuum furnace even at 400 degrees. What is the temperature at the outlet of your vacuum furnace, and what is the flow rate of the liquid drawn from the bottom of the tower?
Each bottom pump of the vacuum tower is equipped with a filter, one in service and one as a spare. A DN20 port is opened on the flange cover of the filter at the bottom of the vacuum tower, to which purge steam is connected. If there is a limit, the inlet valve of the cleaning pump is closed; a piece of iron sheet is placed on the pump’s flange, the filter is cleaned, and then the filter is purged with steam up to the pump inlet.
Are you there? What type of filter is it? Could you tell me? Currently, there is an anti-coking filter at the bottom of one of the pressure reduction towers; the user wants drawings of it. I’m really stuck – it seems like there are specialized manufacturers that produce such filters
Are you there? What type of filter is it? Could you tell me? Currently, there is one at the bottom of the pressure reduction tower
I have a filter installed, with relatively large mesh holes. It has a diameter of about 20 mm; there was originally a layer of fine mesh, which was removed after work began. During operation, coking may occur, which affects the smooth operation of the slag reduction pump; cavitation can also arise, leading to insufficient flow and vacuum conditions. It is necessary to switch the pump promptly and conduct inspections as well as clean-ups. It is still not easy to use a semi-open impeller. The efficiency is too low; even if the coke lumps pass through the pump, they can get stuck elsewhere, making replacement difficult. It will severely affect the long-term stable operation of the device.
Generally, a filter should be installed on the submersible pump as it is beneficial for the pump’s sealing; a Y-type filter is usually the better choice.
It is very necessary to install a filter, especially during the first three days after maintenance when there is too much coke in the tower; a filter makes cleaning easier. It is recommended to use the “T” type instead of the “Y” type; there are manufacturers that specialize in producing them.
It is convenient to install a filter in the pump inlet pipeline for cleaning; it’s more troublesome to do so in the outlet pipeline. Without a filter, could coke deposits form and settle inside the heat exchanger tubes?
Calculate the pressure drop. If the pressure drop across the filter meets the NPSH requirement of the bottom suction pump, then it can be used. Moreover, many devices that employ reduced-pressure deep extraction technology are equipped with such a filter – it is a circular filter cartridge placed in the pipeline, at the inlet of the bottom suction pump! ! There’s no problem
In the unit I’m in, all pump inlets are equipped with filters, usually T-type or Y-type filters
I have a filter here; I clean it more often in case the flow rate isn’t sufficient