Skip to main content

Continuous, On-line Monitoring of Polymer Dose for Dewatering Using Liquid Stream Viscosity

The full text article is not available for purchase.

The publisher only permits individual articles to be downloaded by subscribers.

or click here to sign up for a free trial


This paper describes research conducted to test the use of continuous centrate viscosity measurements for polymer dose monitoring in the biosolids dewatering process. The researchers have previously documented that minimum centrate or filtrate viscosity indicated the optimum polymer dose as determined by capillary suction time (CST) and solids recovery. To date, however, no on-line viscosity measurements have been conducted to test the feasibility of this parameter in continuously monitoring polymer feed.

Initial results indicate that liquid stream viscosity must be measured on-site since filtrate samples in the overdosing range decrease in viscosity over several hours following sampling. A sensitive viscometer is required for continuous monitoring since the observed viscosity range is from 1–3 mPa-sec. An international search for viscometer vendors showed that two types of viscometers could be used for this purpose: rotational and vibrational. Only data from rotational type viscometers was obtained for this paper. The viscometer was installed to continuously sample centrate from the centrifugation of anaerobic digested biosolids. Full-scale dose response experiment showed that minimum viscosity correlates with solids measurements, and thus such viscometers can be used in monitoring and controlling polymer dose during dewatering. However, several modifications are required for such viscometers to withstand the demanding conditions in wastewater treatment plants. Use of viscosity for control of polymer dose requires use of a minimum value, necessitating a complex vontrol algorithm.

Document Type: Research Article


Publication date: January 1, 2002

More about this publication?
  • Proceedings of the Water Environment Federation is an archive of papers published in the proceedings of the annual Water Environment Federation® Technical Exhibition and Conference (WEFTEC® ) and specialty conferences held since the year 2000. These proceedings are not peer reviewed.

    WEF Members: Sign in (right panel) with your IngentaConnect user name and password to receive complimentary access.
  • Subscribe to this Title
  • Membership Information
  • About WEF Proceedings
  • WEFTEC Conference Information
  • Ingenta Connect is not responsible for the content or availability of external websites

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more