The pressure at the inlet and outlet of the SO2 fan varies significantly
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This post was last edited by mkp369 on 2018-3-15 at 09:30. Today it was found that the outlet pressure of the SO2 fan had changed from 30 to 27, while the inlet pressure increased by -7.8. The fan and the dilution valve were not adjusted; the instrumentation staff were notified to check whether all pressure points were normal, and U-tubes were used to measure the resistance in the negative-pressure area equipment. It is currently estimated that the resistance of the foam catchers on the two levels of the drying tower has increased.
There are many factors that can affect the pressure changes at the inlet and outlet of the fan. In the owner’s case, my analysis is that there has been a change in the operating condition of the equipment ahead of the fan. For example, the resistance of the front-mounted equipment increases (which needs to be measured), air leakage decreases, or the capacity of the backup fans declines (if any). In short, it is necessary to analyze and assess various factors in light of actual production conditions
If there are fluctuations in the fan outlet pressure, it is necessary to check whether flooding is occurring inside the dry absorber.
Once, I noticed a leak in the insulation layer of the electrostatic precipitator; air was sucking in from that area, at least several thousand cubic feet per minute. I tried using a rag to block the leak, but it didn’t work. I used several rags in succession, and the air pressure definitely changed. I didn’t go to check it at that time
A clogged demister in the drying tower, high amounts of circulating acid, or a blocked pipeline ahead of the fan can increase the negative pressure at the fan’s inlet, while leaks in the equipment and pipelines downstream can reduce the pressure at the fan’s outlet
It’s blocked; the system isn’t working properly. Check the pressure differences across various sections of the system
After parking the vehicle, the manhole of the drying tower was opened to inspect it, and it was found that the foam trap was severely clogged. After removing it and rinsing it, the blockage was identified as a black, sludge-like substance; after discussion, it was estimated that this substance resulted from oil leakage at the shaft seal of the SO2 fan, which was drawn into the drying tower by the negative pressure mechanism of the shaft seal, corroded there, and eventually caused blockage in the foam trap. After disassembling the negative pressure device for the SO2 fan shaft seal, oil leakage was detected; after addressing the shaft seal leak, the resistance of the foam trap in the drying tower returned to normal.
Pay special attention to whether there is acid sludge clogging in the wire mesh of the dry absorption tower, then check for air leaks in the negative pressure equipment and pipelines, and finally examine the instruments