Level Transmitter Protection

Rosemount Model 5600 non-contacting radar level transmitter with a quartz extended cone......good for your application

I assume that when the flare is active it will be hotter than Hades at the bottom of the flare stack and vicinity. Most of this additional heat is due to radiation; you can install a hood over sensitive instruments and it should minimize the temperature rise the transmitter sees while the flare is active.

Rosemount Model 5600 non-contacting radar level transmitter with a quartz extended cone......good for your application as radar renders safe and accurate performance in high temp aplication.

I think that the issue here is the effect of the increasing ambient temperature on the liquid in the vessel which causes in a change in the liquid density and subsequent inaccuracies not the effect of higher temperature on the device itself.

One thing would be to discuss with your process engineers what the temperature of the liquid in the vessel might actually be in do the necessary correction for density then put the corrected density value in the device configuration (assuming that it is an intelligent device).

The other option as would be to look at some alternative type of measurement, considering that the turbulence in a flare condensate KO drum would usually not be significant the non-intrusive radar or even the guided wave radar may be a good option (expensive though) even a float type variable resistance level transmitter would be suitable.

First you should establish how significant is the effect of the temperature on the condensate also consider carefully the application, what is the intent? what is the control action? what are the real impacts if the transmitter indicates less or more i.e. how detrimental are the consequences? what contingency is in place? what is the impact on the safety of plant personnel? maybe a corrective factor in the device, or on the DCS if a real time temperature measurement is available would be a feasible solution. Is there a sight glass installed on the vessel, may be an earlier than critical alarm (warning) can be configured to prompt operator action to do a visual on the site glass. There are quite a few things that you can think about, ofcourse if the expected inaccuracies are to great and/or your organization is willing to spend the money go for a change out.