Sludge Blanket Levels?

I've asked the staff at my local sewerage authority if that have a suggestion for you. I'll forward a response if it's pertinent.

Jerry

All the plants I've seen use ultrasonic. Hawk

make a range of ultrasonic level transmitters for waste-water applications and they're very easy to set up and pretty reliable.

Another option is something from Drexelbrook. They have a wide range of contact-type magnetostrictive transmitters which can discriminate between the blanket and the water underneath and it might be worth talking to one of their reps..

HTH, Cameron:-)

I'm not familiar with the term "sludge blanket" -- I'm in the upstream oil and gas industry -- but our mud tanks often have an amount of froth sitting atop the drilling mud, making accurate measurement of mud volumes more difficult. In such cases we may use microwave sensors rather than the usual ultrasonic.

Any info on this?

The sludge blankets I knew formed at the bottom of a settling tank. I haven't heard back from the staff yet. Maybe I'll stop in tomorrow.

Jerry

Hi, Have you tried Royce Technologies "Interface Level Analyzers and Sensors"? This is an Ultrasonic sensor suspended under the water surface in a Thickener (usually from the rotating or fixed bridge supporting the rake mechanism). Provides a continues level measurement of the sludge blanket as well as an additional Clarity (opcaity of the liquid) signal. I have used them and had success in wate water / mining (Clarifier / Thickener) applications.

Regards, Raj

There is standard equipment made for this application from a number of manufacturers. Royce in the US has a reliable product, as does Krohne. Both optical and ultrasonic measurement techniques are satisfactory, but if your sludge blanket interface is not well defined I suggest you use the optical technology as it is a better discriminator of the interface (e.g. in a water clarifier). The ultrasonic is suitable in wastewater clarifiers or in the alumina industry.

Dennis