3 replies to this topic

[RajD]

Hi Everyone,

For a project, we have two types of Kettle type reboilers - Type 1: With Weir; Type -2: Without Weir

 

I have to assign Liquid Levels as follows:

1. LAHH - High High Liquid Level (High High Level Shutdown) - Can these be specified as 90-95% of the kettle diameter or will that be too high because it will take away all the vapor space and start taking liquid back to the column. 

2. LAH - Low Liquid Level (High Level Alarm)

3. NLL - Normal Liquid Level (Normal Operating)

4. LAL - Low Liquid Level (Low Level Alarm)

5. LALL - Low Low Liquid Level (Low Low Level Shutdown)

 

What should be the criteria and basis for assigning the levels for these on the tube bundle side only (for Type 1 or Type 2)? Appreciate if some experts can share some information.

 

I am not looking for the liquid levels on Type 1 on the liquid reservoir side.

[Pilesar]

For a kettle reboiler, liquid level is maintained above the tubes. Usually 2 inches of liquid minimum with additional liquid height for foaming service. Only set alarms where needed to alert the operator that action needs to be taken. What harm could happen on low low level? Would it need to automatically shut down? If not, do not set such an alarm! Only set alarms where they can be useful.

[breizh]

Hi,

Bundle should be always submerged, the reason why you have a weir (gravity flow type).

Other configuration with level transmitter and control valve on the liquid discharge line is more expensive Capex (equipment and control) and Opex (maintenance)

my 2 cents

Breizh

[RajD]

Thanks for the prompt responses.