Current surge of the high-concentration forced circulation pump during caustic soda evaporation
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This post was last edited by sunjl1981 on 2013-1-7 00:07. The current drawn by the forced circulation pump used in the caustic soda evaporation process is normally 80 amps, but it drops periodically to 55 amps every 4-5 minutes, before returning to around 80 amps again after 30-40 seconds. When the current changes, the vacuum level and temperature in that system also change. Could experts please explain why this happens? This post was last edited by wang*neng on 2009-3-11 16:44 ] # hcbbs
Check what the discharge cycle is and see if it’s related to this. Also, the material transfer time can be observed as well.
How did the high vacuum level and temperature change at that time? Is there some connection with salt separation?
Thank you all for your answers. I conducted such a test: with both the discharge valve and the feed valve closed, while the salt extraction pump and the forced circulation pump continued to operate, the current of the circulation pump still experienced periodic fluctuations. When the current decreased, the vacuum level dropped and the temperature rose. I’m not sure if you experts can understand me describing it this way. This post was last edited by limingshuguang on 2009-3-4 09:20]
Has it always been like this? If so, it is necessary to check whether the impeller blades of the forced pump are balanced and whether any deviations have occurred due to wear from salt and alkali. Because when the current changes, the speed and amount of material circulation within the cell change, and unstable circulation amounts will inevitably lead to changes in vacuum and material temperature. This post was last edited by limingshuguang on 2009-3-4 09:19]
Then the cause can only be sought in the device itself. What is mentioned on the 5th floor refers to one aspect; it is also necessary to check for the possibility of intermittent air intake and the risk of salt formation. Last edited by sister on 2009-3-4 08:11]
It’s normal for the current to fluctuate, but as you said, if these fluctuations occur even with both the inlet and outlet valves closed, it seems necessary to look for the cause in the current readings. During the circulation process of the evaporator material, it inevitably causes changes in the current.
First, wash it with the concentrated cleaning solution; if that doesn’t work, it’s recommended that you remove the pump unit while the vehicle is parked and take a look at it.
Check whether there is any blockage at the pump inlet, that is, at the outlet for the concentrated fluid. When the pump inlet is blocked or for some other reason, insufficient fluid enters the pump, resulting in reduced power consumption and a decrease in current. At the same time, cavitation noises can be heard inside the pump chamber. After some time, when the blockage is removed, the current returns to normal levels and the flow rate also normalizes. When the pump’s internal components are blocked, the liquid level rises and a large amount of steam is generated; as a result, the vacuum level decreases while the temperature rises.
Check whether salt has formed in the heating chamber, and also check if the pump impeller is corroded or misaligned. It’s a pretty strange situation.
Changes are normal; if they exceed the range, check whether the outlet is blocked
Agree with the analysis on floor 9; it’s likely a temporary blockage or cavitation phenomenon.
Is it caused by equipment restructuring or process changes, such as a change in the feeding position? :)
The periodic changes you mentioned indicate that there is a problem with the design of your evaporator. Consider two aspects. First is the height of the circulation pipe and its structure ； The second is the static pressure height above the heating chamber. It has nothing to do with the pump. If the height of the vaporization chamber in your evaporator is sufficient, it is recommended to raise the liquid level and observe the changes in the pump’s current.
If the pump cannot draw in liquid, or draws in liquid intermittently, the current drawn by the pump will vary significantly
Check whether the feed pipe is perforated (the part inside the reactor), or whether the circulating material contains a large number of bubbles.