Application and optimization of electric field-assisted ultrasonication for disintegration of waste activated sludge using response surface methodology with a Box-Behnken design

Title
Application and optimization of electric field-assisted ultrasonication for disintegration of waste activated sludge using response surface methodology with a Box-Behnken design
Authors
정경원황민진차민정안규홍
Keywords
Waste activated sludge; Disintegration; Eletric field; Ultrasonication; Eletric field-assisted ultrasonication; Response surface methodology
Issue Date
2015-01
Publisher
Ultrasonics sonochemistry
Citation
VOL 22, 437-445
Abstract
In the present study, an electric field is applied in order to disintegrate waste activated sludge (WAS). As a preliminary step, feasibility tests are investigated using different applied voltages of 10–100 V for 60 min. As the applied voltage increases, the disintegration degrees (DD) are gradually enhanced, and thereby the soluble N, P, and carbohydrate concentrations increase simultaneously due to the WAS decomposition. Subsequently, an optimization process is conducted using a response surface methodology with a Box–Behnken design (BBD). The total solid concentration, applied voltage, and reaction time are selected as independent variables, while the DD is selected as the response variable. The overall results demonstrate that the BBD with an experimental design can be used effectively in the optimization of the electric field treatment of WAS. In the confirmation test, a DD of 10.26 ± 0.14% is recorded, which corresponds to 99.1% of the predicted response value under the statistically optimized conditions. Finally, the statistic optimization of the combined treatment (electric field + ultrasonication) demonstrated that even though this method is limited to highly disintegrated WAS when it is applied individually, a high DD of 47.28 ± 0.20% was recorded where the TS concentration was 6780 mg/l, the strength of ultrasonication was 8.0 W, the applied voltage was 68.4 V, and the reaction time was 44 min. E-SEM images clearly revealed that the application of the electric field is a significant alternative method for the combined treatment of WAS. This study was the first attempt to increase disintegration using the electric field for a combined treatment with ultrasonication.
URI
http://pubs.kist.re.kr/handle/201004/48050
ISSN
13504177
Appears in Collections:
KIST Publication > Article
Files in This Item:
There are no files associated with this item.
Export
RIS (EndNote)
XLS (Excel)
XML


qrcode

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

BROWSE