{"id":{"repo_id":"vt","oai_identifier":"oai:vtechworks.lib.vt.edu:10919/33650"},"canonical_url":"https://search.dev.ndltd.org/etd/vt/oai:vtechworks.lib.vt.edu:10919/33650","repository":{"repo_id":"vt","name":"Virginia Tech","base_url":"https://vtechworks.lib.vt.edu/oai/request"},"display":{"title":"High-Intensity Shear as a Wet Sludge Disintegration Technology and a Mechanism for Floc Structure Analysis","abstract":"By shearing activated sludge using a high shear rotor stator device, bioavailable proteinaceous material can be produced. Operation at elevated temperatures, serves to increase the amount of material that is rendered soluble (<0.45 um) and biodegradable. The storage of sludge under anoxic condition prior to shearing does not appear to enhance solublization of solids, though deflocculation and deterioration of dewaterablility was observed. Anaerobic digestibility appears to be enhanced by the addition of a high shear as shown by increases in gas production and volatile solids destruction. The dewatering properties of activated sludge, measured by capillary suction time, deteriorated with the addition of sheared solids, but reaeration resulted in near complete recovery. The role of iron and iron chemistry plays a critical role in the activated sludge. Iron apparently selectively removes protein, in particular material ranging in the 1.5 um to 30K size range. The addition of ferric iron was found to increase SVI and decrease zone-settling velocity, when added to reactors with mechanically disintegrated sludges. Similar trends were not observed in reactors dosed with ferrous iron. Preliminary results suggest that the ferric/ferrous redox chemistry may serve to enhance floc structure, as observed by increased settling velocity and shear resistance for sludges dosed with ferrous sulfate.","abstract_html":"By shearing activated sludge using a high shear rotor stator device, bioavailable proteinaceous material can be produced. Operation at elevated temperatures, serves to increase the amount of material that is rendered soluble (&lt;0.45 um) and biodegradable. The storage of sludge under anoxic condition prior to shearing does not appear to enhance solublization of solids, though deflocculation and deterioration of dewaterablility was observed. Anaerobic digestibility appears to be enhanced by the addition of a high shear as shown by increases in gas production and volatile solids destruction. The dewatering properties of activated sludge, measured by capillary suction time, deteriorated with the addition of sheared solids, but reaeration resulted in near complete recovery. The role of iron and iron chemistry plays a critical role in the activated sludge. Iron apparently selectively removes protein, in particular material ranging in the 1.5 um to 30K size range. The addition of ferric iron was found to increase SVI and decrease zone-settling velocity, when added to reactors with mechanically disintegrated sludges. Similar trends were not observed in reactors dosed with ferrous iron. Preliminary results suggest that the ferric/ferrous redox chemistry may serve to enhance floc structure, as observed by increased settling velocity and shear resistance for sludges dosed with ferrous sulfate.","abstract_has_math":false,"creators":["Muller, Christopher D."],"institution":"Virginia Tech","degree_name":"Master of Science","degree_level":"masters","degree_discipline":"Environmental Sciences and Engineering","degree_department":"Environmental Sciences and Engineering","school":null,"contributors":[],"advisors":[],"committee_chairs":["Novak, John T."],"committee_members":["Randall, Clifford W.","Love, Nancy G."],"year":2001,"date_issued":"2001-05-29","date_published":"2001-05-29","updated_at":"2026-07-22T22:20:25Z","subjects":["biodegradation","solids reduction","floc structure","disintegration","iron"],"languages":[],"rights":["In Copyright"],"rights_urls":["http://rightsstatements.org/vocab/InC/1.0/"],"identifier_entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["etd-06192001-143911"],"render_values":[{"text":"etd-06192001-143911","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/10919/33650","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.committeechair","label":"Committee Chair","values":["Novak, John T."]},{"key":"dc:contributor.committeemember","label":"Committee Member","values":["Randall, Clifford W.","Love, Nancy G."]},{"key":"dc:contributor.department","label":"Department","values":["Environmental Sciences and Engineering"]},{"key":"dc:creator","label":"Author","values":["Muller, Christopher D."]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2014-03-14T20:40:14Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2014-03-14T20:40:14Z","2004-06-19"]},{"key":"dc:date.issued","label":"Date","values":["2001-05-29"]},{"key":"dc:publisher","label":"Institution","values":["Virginia Tech"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Environmental Sciences and Engineering"]},{"key":"thesis:degree_level","label":"Degree Level","values":["masters"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Virginia Polytechnic Institute and State University"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["biodegradation","solids reduction","floc structure","disintegration","iron"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:rights","label":"Dc Rights","values":["In Copyright"]},{"key":"dc:rights.uri","label":"Rights URI","values":["http://rightsstatements.org/vocab/InC/1.0/"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["etd-06192001-143911"]},{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/10919/33650"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["By shearing activated sludge using a high shear rotor stator device, bioavailable proteinaceous material can be produced. Operation at elevated temperatures, serves to increase the amount of material that is rendered soluble (<0.45 um) and biodegradable. The storage of sludge under anoxic condition prior to shearing does not appear to enhance solublization of solids, though deflocculation and deterioration of dewaterablility was observed. Anaerobic digestibility appears to be enhanced by the addition of a high shear as shown by increases in gas production and volatile solids destruction. The dewatering properties of activated sludge, measured by capillary suction time, deteriorated with the addition of sheared solids, but reaeration resulted in near complete recovery. The role of iron and iron chemistry plays a critical role in the activated sludge. Iron apparently selectively removes protein, in particular material ranging in the 1.5 um to 30K size range. The addition of ferric iron was found to increase SVI and decrease zone-settling velocity, when added to reactors with mechanically disintegrated sludges. Similar trends were not observed in reactors dosed with ferrous iron. Preliminary results suggest that the ferric/ferrous redox chemistry may serve to enhance floc structure, as observed by increased settling velocity and shear resistance for sludges dosed with ferrous sulfate."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["Master of Science"]},{"key":"dc:title","label":"Title","values":["High-Intensity Shear as a Wet Sludge Disintegration Technology and a Mechanism for Floc Structure Analysis"]}]}],"canonical_facts":{"dc:contributor.committeechair":["Novak, John T."],"dc:contributor.committeemember":["Randall, Clifford W.","Love, Nancy G."],"dc:contributor.department":["Environmental Sciences and Engineering"],"dc:creator":["Muller, Christopher D."],"dc:date.accessioned":["2014-03-14T20:40:14Z"],"dc:date.available":["2014-03-14T20:40:14Z","2004-06-19"],"dc:date.issued":["2001-05-29"],"dc:description.abstract":["By shearing activated sludge using a high shear rotor stator device, bioavailable proteinaceous material can be produced. Operation at elevated temperatures, serves to increase the amount of material that is rendered soluble (<0.45 um) and biodegradable. The storage of sludge under anoxic condition prior to shearing does not appear to enhance solublization of solids, though deflocculation and deterioration of dewaterablility was observed. Anaerobic digestibility appears to be enhanced by the addition of a high shear as shown by increases in gas production and volatile solids destruction. The dewatering properties of activated sludge, measured by capillary suction time, deteriorated with the addition of sheared solids, but reaeration resulted in near complete recovery. The role of iron and iron chemistry plays a critical role in the activated sludge. Iron apparently selectively removes protein, in particular material ranging in the 1.5 um to 30K size range. The addition of ferric iron was found to increase SVI and decrease zone-settling velocity, when added to reactors with mechanically disintegrated sludges. Similar trends were not observed in reactors dosed with ferrous iron. Preliminary results suggest that the ferric/ferrous redox chemistry may serve to enhance floc structure, as observed by increased settling velocity and shear resistance for sludges dosed with ferrous sulfate."],"dc:description.degree":["Master of Science"],"dc:identifier.other":["etd-06192001-143911"],"dc:identifier.uri":["http://hdl.handle.net/10919/33650"],"dc:publisher":["Virginia Tech"],"dc:rights":["In Copyright"],"dc:rights.uri":["http://rightsstatements.org/vocab/InC/1.0/"],"dc:subject":["biodegradation","solids reduction","floc structure","disintegration","iron"],"dc:title":["High-Intensity Shear as a Wet Sludge Disintegration Technology and a Mechanism for Floc Structure Analysis"],"dc:type":["Thesis"],"thesis:degree_discipline":["Environmental Sciences and Engineering"],"thesis:degree_level":["masters"],"thesis:degree_name":["Master of Science"],"thesis:institution_name":["Virginia Polytechnic Institute and State University"]},"updated_at":"2026-07-22T22:20:25Z"}