Application of a Flat Surface pH Electrode to Demonstrate the Effect of Lime Addition Point Relocation on Mixing Quality and pH Decay of Lime Stabilized Biosolids
Abstract:Uniform lime incorporation into sewage sludge is critical for biosolids lime stabilization processes. There is no Class B biosolids regulation for lime incorporation. The slurry method is currently used to evaluate the pH of limed biosolids, but this method homogenizes the biosolids and potentially masks poor lime mixing. In this study, a flat surface pH electrode was used in a full-scale experiment to measure the pH of lime stabilized biosolids without creating slurries. The standard deviation of fifteen pH measurements at different locations in a biosolid sample was used to assess mixing quality and the effectiveness of relocating the point at which lime was added to dewatered sludge. Well mixed limed biosolids had consistently high pHs (near 12) with low standard deviations (<0.5 pH units), while poorly mixed biosolids had areas with low pH (<10) and high standard deviations (>2.0 pH units). Poorly mixed biosolids exhibited rapid and marked pH decay, while well mixed biosolids resisted pH decay.
Document Type: Research Article
Publication date: 2007-10-01
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 These proceedings are not peer reviewed. A subscription to the Proceedings of the Water Environment Federation includes access to most papers presented at the annual WEF Technical Exhibition and Conference (WEFTEC) and other conferences held since 2000. Subscription access begins 12 months after the event and is valid for 12 months from month of purchase. A subscription to the Proceedings of the Water Environment Federation is included in Water Environment Federation (WEF) membership.
WEF Members: Sign in (right panel) with your IngentaConnect user name and password to receive complimentary access. Access begins 12 months after the conference or event
- Subscribe to this Title
- Membership Information
- About WEF Proceedings
- WEFTEC Conference Information
- Learn about the many other WEF member benefits and join today
- Ingenta Connect is not responsible for the content or availability of external websites