Consolidation and drying properties of sewage sludge
Item Type:Invited Talk
Citation:O'Kelly B.C., Consolidation and drying properties of sewage sludge, Invited presentation at the Geotechnical Society of Ireland Research Seminar, Dublin, 14th March, 2005
Invited presentation _Consolidation and drying properties of sewage sludge_14th March 2005.pdf (Accepted for publication (author's copy) - Peer Reviewed) 660.3Kb
The consolidation and air-drying properties of dewatered sewage sludge from Tullamore municipal wastewater treatment plant were studied using soil laboratory tests. Biologically active, and stabilized samples prepared in the laboratory, were consolidated using the oedometer apparatus and the large hydraulic consolidation cell. Index tests, including specific gravity of solids and loss in mass on ignition, were used to quantify the level of biological digestion of the test material. Sludge in the liquid state had a low permeability of the order of 10-9m/s, while consolidated sludge material was practically impermeable. Flocs of mainly organic clay-sized particles, which comprised roughly 90% of the solids, trapped the pore water, resulting in the very low permeability measured. Consolidation largely occurred as a result of creep, and in the long-term, due to decomposition of the solids. Greater levels of biological digestion reduced the organic content and produced a more free-draining material. The application of the test data in engineering the efficient landfill disposal of the sludge material, and predicting the long-term rates of settlement, biogas and leachate generation at the landfill, are presented.
Author: O'Kelly, Brendan C.
Other Titles:Invited presentation at the Geotechnical Society of Ireland Research Seminar
Type of material:Invited Talk
Availability:Full text available