How to address the fluctuations in the outlet pressure of both pumps during production?
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This post was last edited by liu530014416 on 2022-12-13 at 11:25. Dear teachers, the tower pressure is controlled at -70 Kpa. W-1520 is located about 12 meters away from B-1500, while W-1510 is about 18 meters away from B-1500. Currently, the pressure at the outlet of the pump used for drawing liquid from the intermediate tank fluctuates frequently and then returns to normal after 1 minute; the same issue occurs with the backup pump. It seems that air is getting into the pumps. How can this problem be solved?
As an extra remark, one needs to find the cause in order to solve it:D
Is it possible for feeding and discharging to occur simultaneously? The vortex generated by feeding may cause vacuum to form at the bottom discharge port. Is the liquid inside the pump prone to vaporization? This problem often occurs when liquid ammonia is used
Next time there is a fluctuation, you can assess whether vaporization is causing pressure fluctuations at the beginning of the pump’s operation by taking into account the pump’s current and the sounds heard on site. Additionally, I see that the temperature of the intermediate tank is 113.98. Could it be that there is water deposited at the pump inlet before startup, which is vaporized by the high-temperature material, resulting in pressure fluctuations at the beginning of pump operation?
When sampling, the liquid level was too low. A minimum working liquid level must be maintained.
The control level is not low; it is currently 50%, and it was increased to 60% in the past, with no significant change
The material contains water; it is advisable to check the discharge at the backup pump inlet to see if stratification is present
This post was last edited by Le Taotao on 2022-12-16 at 11:35. Check the saturated vapor pressures of the material components at -70 kPa; it is possible that these components will vaporize at this pressure, leading to brief vaporization of the pump. Furthermore, if the distance between the condenser and the storage tank is sufficient, the required height can be calculated based on the density of the components; by adding a liquid seal, the pressure in B1500 can be maintained at atmospheric pressure or slightly negative pressure, thereby increasing the pressure at the pump inlet.
What is the temperature of the liquid being pumped? It’s possible that the high temperature facilitates vaporization; the negative pressure generated during pumping causes the liquid to vaporize
Method 1: Make some vent holes in the feed pipe of the intermediate tank to ensure that there is no air in the feed. Method 2: Increase the circulating water flow in the secondary condenser to its maximum, and at the same time raise the reflux rate from 3 tons to 3.5 tons in order to lower the temperature at the top of the tower. At the same time, raise the liquid level in the intermediate tank to 65–70%, and increase the size of the self-return valve that pumps the *** product back into the intermediate tank. Overall, the intention is to lower the temperature of the intermediate tank and disperse the deposited moisture throughout the tank. :):)
The fluctuation in pump pressure is likely due to cavitation. There are several ways to address this issue: 1) Increase the inlet pressure; 2) Lower the temperature of the medium; 3) Reduce pipeline resistance; 4) Change the size of the pump’s suction inlet. As temporary solutions on-site, one could increase the pressure at the top of the tower, enhance the cooling effect of the circulating water in the condenser, and check whether the filter is clogged or if its mesh size is too small