Fault in desulfurization liquid circulation pump
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There are two units, and both have problems – it’s frustrating. The model seems to be CZ 250-500B chemical centrifugal pumps used in the HPF desulfurization process. Unit #1 makes a lot of noise, and the temperature of its bearing box is high; the flow rate into the regeneration tower is 800 m3/H, while the outlet pressure is 0.44 MPa. All these values remain stable, but there’s a lot of noise coming from the impeller area, which sounds like water hammer. Unit #2 has a motor temperature of around 78°C, and the pressure gauge shows abnormal readings around 0.2 MPa. The flow rate is also 800 m3/H, but the power requirement for this unit is much higher than that of Unit #1. I disassembled Unit #2 today, and I found that the edges of the impeller’s inner cover were a bit rough. I hope experienced colleagues can help analyze this situation! Thank you!! This post was last edited by ice-coffee on 2009-3-27 00:51
Once, our desulfurization fluid circulation pump encountered a problem similar to the one you mentioned. After disassembling the pump, no issues were found, but it still failed to build pressure once it was reassembled. When it was disassembled later, the inlet and outlet pipes were checked at the same time, and it was found that a sampling bottle (a PVC bottle containing analysis reagents) was stuck in the pump’s inlet pipe. Check if there is debris stuck in your pump
Based on situation #2 you mentioned, it’s likely that the impeller in #1 is not in good condition either. 1# The impeller makes a loud noise; is there a water hammer sound, which could indicate cavitation? Is there any vibration?
Just guessing. The flow rate of Pump No. 1 is stable, so cavitation can be ruled out, as cavitation causes fluctuations in pressure and flow rate; check the pump casing for any small foreign objects ； 2# There might be other reasons as well; something could be causing the insufficient supply of materials, such as air leakage, but you say the flow rate is normal, which is contradictory. During operation, it is advisable to check both the vibration of the pump and the motor, as well as the current of the motor at the same time; by combining these measurements, an accurate assessment can be made.
Pump No. 1 is likely not suffering from cavitation or vacuum conditions, as the flow rate and pressure are stable; it’s possible that something has gotten inside it or that the impeller is loose. The vibration isn’t high, is it? If the pressure of Pump 2 is not high, could it be that the inlet is blocked? How can we tell if its power is greater than that of Pump 1?
Air may have entered the pump; enhance exhaust by ensuring proper exhaust at the top of the pump casing and the pipes. Try again after confirming this. If that doesn’t work, the impeller is likely unbalanced – check for static balance and try again.
As mentioned above, we have also encountered situations where something got stuck inside the pump, and over time signs of cavitation on the impeller could be observed