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Sludge Concentration Inline Measurement
suspended solid measurement in pipeline (Sludge Concentration) in sewage. up to 7%

Hi

I am looking for the best way to measure the concentration of sludge in sewage treatment in flow up to 7% SS (70000 mg/l). I know IR sensor been used but for up to 5% SS, ultrasonic also used. however, I am looking for low cost sensor.

please if you have any suggestion or any one expert in this field guide me with best option. I am thinking of buying ultrasonic probe from Amazon then I use LabVIEW as data acquisition and process the signal or do you think its not worth to try.

Thank you very much and I am looking for your reply.

By Woolsey-Mike on 13 June, 2017 - 9:35 am
1 out of 1 members thought this post was helpful...

Hi

Most important is what kind of sludge, not just concentration.
Primary, Waste Activated, chemical sludge, digested sludge....

Please advise.

Hi,

thank you for your reply. It's primary sludge. It's feed to drum thickener from big sewage tanks.

Thank you

Hi,

thank you for your reply. It's primary sludge. It's feed to drum thickener from big sewage tanks.

Thank you

Sewage sludges are very hard to make online concentration (density) measurements on. The difference between the dry solids specific gravity of the sludge and the density of water is very small. Much of what you see is color, not exactly density. In addition, the dry solids specific gravity of the sludge is constantly changing because the constituents of the sludge are changing continuously. You CAN make this measurement, but only if you are willing to live with a very wide error band.

My recommendation is to study your process and see if you can control it using three or four grab samples and lab analysis every shift. Most of the time, these processes are pretty steady state, and you can likely control it without a continuous concentration measurement.

Best of luck,

Walt Boyes, Life Fellow, ISA; Fellow InstMC
Chartered Measurement and Control Technologist,
Member Assoc. of Professional Futurists
Spitzer and Boyes LLC

**Spitzer and Boyes LLC publishes the Industrial Automation and Process Control INSIDER (www.iainsider.com)**