Insights on the solubilization products after combined alkaline and ultrasonic pre-treatment of sewage sludge
Trzcinski, Antoine Prandota
Ng, Wun Jern
Date of Issue2014
School of Civil and Environmental Engineering
Nanyang Environment and Water Research Institute
This work provides insights on the solubilization products after a simultaneous combination of alkaline and ultrasonic (ALK + ULS) pre-treatment of sewage sludge. Soluble chemical oxygen demand (SCOD) increased from 1200 to 11,000 mg/L after such treatment. Organics with molecular weight around 5.6 kDa were solubilized because of the synergistic effect of ultrasound and alkali. Organics with molecular weight larger than 300 kDa increased from 7.8% to 60%, 16% and 42.3% after ULS, ALK and ALK + ULS treatment, respectively. Excitation emission matrix fluorescence spectroscopy analysis identified soluble microbial product-like and humic acid-like matters as the main solubilization products. Sludge anaerobic biodegradability was significantly enhanced with the simultaneous application of ALK + ULS pre-treatment. ALK + ULS pre-treatment resulted in 37.8% biodegradability increase compared to the untreated sludge. This value was higher compared to the biodegradability increase induced by individual ALK pre-treatment (5.7%) or individual ULS pre-treatment (20.7%) under the same conditions applied.
Journal of environmental sciences
© 2014 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. This paper was published in Journal of Environmental Sciences and is made available as an electronic reprint (preprint) with permission of Elsevier B. V. The paper can be found at the following official DOI: [http://dx.doi.org/10.1016/j.jes.2014.07.024]. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper is prohibited and is subject to penalties under law.