Level Sensor for Tank, High Viscous Product

Google optical level sensors

• Put the tank on weigh-cells.
• Non-contact radar.

I have never used it, but optical infrared might be worth looking at.

Both guided wave and pulse radar react to the change in dielectric as the basis of their detection technology.

The obvious problem with guided wave is build-up on the probe.Your material has some dielectric value, all refined products do.

Non-contact radars can produce a reading with quite low dielectric materials and generally don't care about the atmosphere - whether it is vapor, mixed air and vapor or mostly air like ultrasonics does.

For the non-contact technologies, keep the unit away from the side wall to prevent reflection problems.

I forgot to say. The instrument is required for continuous level measurement. Is it used optical technology for continuous measurment or only for point measurement (level switches)?

The technology is correctly called laser, not infrared. Yes, it is continuous level measurement, not point level. Opacity of the liquid affects the measurement.

ABB bought K-Tek. Might be worth a call to ABB.

http://new.abb.com/products/measurement-products/level/laser-level-transmitters

• Non-Intrusive, Never Touches the Fluid
• Eliminates Fluid Contamination
• No Calibration Needed
• 
  
• http://www.gemssensors.com/Level/Single-Point-Level-Switches/Piezo-Resonant-ExOsense

I think he is wanting a level (reading from bottom to top allowable in a continuous range, and readings constantly updated) not a level switch type sensor.

The item you pointed out is surpassing (as usual) for a liquid level switch application, not so much for actual tank level in feet.

The crude oil guys have a pressure system that's not dependent on density I think. Don't remember more.

I personally would choose radar or wave-guided radar, simply because, it relies on a reflected radio signal, and I am pretty sure your whatever viscous chemical will not be "stealth" material, thus radio will reflect. I don't even think wave-guide radar is needed, but do talk to the product specialists on this before decision time. They might even advise to have redundant sensors installed so switch-over is instantaneous if need be when PM is done on any sensor that has "glazed" over.

By the way, I suspect differential pressure will work, however slow in response in this instance. Fouling of the sensor diaphragm can be avoided, if the interstitial space between tank and sensor flange is some how filled (use a density trap) with a less viscous (non-contaminating, non-reactive) fluid. It is not insurmountable, just probably more trouble than it is worth to you.