Linked Life Data

19149352

Source:http://linkedlifedata.com/resource/pubmed/id/19149352

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
2009-1-19
pubmed:abstractText
Conventional activated sludge wastewater treatment plants currently produce a large quantity of excess sludge. To reduce this sludge production and to improve sludge characteristics in view of their subsequent elimination, an ultrasonic cell disintegration process was studied. In a lab-scale continuous flow pilot plant, part of the return sludge was sonicated by low-frequency and high-powered ultrasound and then recycled to the aeration tank. Two parallel lines were used: one as a control and the other as an assay with ultrasonic treatment. The reactors were continuously fed with synthetic domestic wastewater with a COD (chemical oxygen demand) of approximately 0.5 g l(-) corresponding to a daily load of 0.35-0.50 kg COD kg(-1) TS d(-1). Removal efficiencies (carbon, particles), excess sludge production and sludge characteristics (particle size distribution, mineralization, respiration rate, biological component) were measured every day during the 56-day experiment. This study showed that whilst organic removal efficiency did not deteriorate, excess sludge production was decreased by about 25-30% by an ultrasonic treatment. Several hypotheses are advanced: (i) the treatment made a part of the organic matter soluble as a consequence of the floc disintegration, and optimised the conversion of the carbonaceous pollutants into carbon dioxide and (ii) the treatment modified the physical characteristics of sludge by a mechanical effect: floc size was reduced, increasing the exchange surface and sludge activity. The originality of this study is that experiments were conducted in a continuous-flow activated sludge reactor rather than in a batch reactor.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0959-3330
pubmed:author
pubmed:issnType
Print
pubmed:volume
29
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1307-20
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
Reduction by sonication of excess sludge production in a conventional activated sludge system: continuous flow and lab-scale reactor.
pubmed:affiliation
Laboratoire Optimisation de la Construction et Ingénierie de l'Environnement, Polytech'Savoie, Université de Savoie, 73376 Le Bourget du Lac, France.
pubmed:publicationType
Journal Article