Liquid slugging occurred after the modification of the steam condensate in the distillation column reboiler

There are several possible causes of water hammer: improper pipeline design, excessive steam flow, poor drainage of condensate, and issues with the internal structure of the condenser. Solutions may include adjusting the steam flow rate, optimizing the pipe design to ensure smooth drainage of condensate, and checking and improving the internal structure of the condenser. .

Check whether the pressure of the condensate discharge is below the saturation temperature; the pressure must remain above the saturation pressure corresponding to that temperature, otherwise liquid slugging will occur. The pressure is too low, causing part of the liquid to vaporize, which in turn leads to the liquid hitting the valves and pipelines

Modification requires design calculations, which are related to saturated liquid at parameters such as flow rate, pressure, temperature, and pipe resistance. As can be seen from the diagram, the pipes have too many upward and downward bends; once the flow rate changes, it will inevitably lead to a decrease in local pressure, causing the liquid to vaporize and then re-condense when cooled. This is what results in the phenomenon of liquid slugging, for reference only.

What parameters are used to adjust the opening degree of the control valve assembly? There are similar operating conditions, with a condensate collector installed in front of the control valve. The level of the condensate collector is set, and the opening degree of the control valve is regulated via a PID controller, in order to achieve automatic drainage, prevent steam from being entrained, and save steam. After adjusting the valve assembly, the pipeline rose by 18 meters, and liquid slugging would occur once steam and water mixed. (Expansion and vaporization may also occur when the flow rate changes.) A deaerator is connected afterward; if it is a thermal deaerator, saturated steam needs to be supplied. The pressure at the condensate outlet must be higher than the operating pressure of the deaerator; otherwise, liquid slugging may also occur. Suggestion: First, prevent vapor from entering the drainage line; if that doesn’t work, install a water storage tank behind the control valve and use a pump to send the water to a higher level.

Through schematic analysis, it is highly likely that the steam exiting the reboiler is a mixture of steam and water, and the pressure in the pipeline downstream of the control valve should fluctuate frequently; as a result, water hammer is inevitable. You can refer to the suggestions on floor 5 for improvements.

Pipeline resistance increases, fluid pressure drops, the saturated liquid vaporizes and flashes, resulting in a two-phase flow

What was said on the 5th floor makes sense; considering adding a gas-liquid separator tank to supply only hot water would be a good option

Is there a buffer tank installed in front of the control valve? Increase back pressure? Low-point hydrophobicity?

It is estimated that you are performing energy coupling to recover the heat from the condensate; the heat removed by the reboiler is less than the heat released during steam liquefaction, meaning that the steam heat is not fully utilized. As a result, the vapor-liquid mixture moves forward. It is recommended to first check whether the energy levels are balanced, which can help reduce the amount of steam required.