With several filters operating in parallel, how can one determine which filter is clogged and needs to be cleaned?

To determine whether a filter is clogged, the following points can be considered: 1. Observe the flow rate: Generally, each filter should have a similar flow rate; if the flow rate of a particular filter decreases significantly, it is likely that this filter is clogged. 2. Check the pressure: A clogged filter will cause an increase in the pressure difference before and after it, which can be determined by reading the pressure gauge. 3. Check the effect: If the quality of the filtered liquid or gas deteriorates, it is likely that the filter is clogged. 4. Noise variation: If the filter becomes clogged, it may cause changes in the equipment’s noise level. 5. Verify resistance: If the normal operating resistance of the device is known, then any value exceeding this resistance may indicate a clogged filter. 6. Direct inspection: If the above methods cannot determine the issue, then it is necessary to disassemble the filter directly for inspection. Once a clogged filter is detected, it must be cleaned or replaced immediately to prevent disruption to the normal operation of the equipment. .

Differential pressure transmitters are installed before and after the filter; the average value of data collected over one month after installation is used as the standard value, and it is determined how many percent the pressure exceeds this value and for how long in order to identify blockage.

Close each inlet and outlet one by one, and monitor the pressure difference before and after the filter group. *** If the pressure difference remains unchanged or changes only slightly after a particular outlet is closed, it indicates that that filter is clogged.

This post was last edited by qugd on 2023-9-27 at 12:40. I agree with the opinion of the friend above; if there is pressure (at the inlet and outlet) or a differential pressure transmitter before and after the filter, it is possible to estimate the value based on the data recorded by the DCS or data acquisition system. It’s such a trivial matter – why is it necessary to go through seven or eight steps of evaluation? That kind of approach isn’t typical of those who truly work in the chemical industry.

I particularly disagree with point 3 you mentioned. What is your basis for claiming that the quality of the material filtered will decline when the filter becomes clogged? For example, in a water filtration device, if the filter becomes clogged, the quality of the filtered water will worsen and it will become more turbid, right?

With parallel filters, it is impossible to determine which one is clogged; just like the filter cartridges in dust collectors, they all need to be cleaned as a whole. To determine this, each unit must be tested separately; pressure gauges should be installed before and after the filter, and if the pressure difference at a specific flow rate exceeds a certain value, it is considered to be clogged

Adding a differential pressure gauge to measure the inlet and outlet pressures of each filter, or installing a flow meter at the outlet of each filter, can also provide information