Dewatering is the first step in the subsequent treatment and disposal of food waste digestate (FWD). However, FWD is difficult to dewatering. In this study, persulfate was synergistic oxidized by ozone to improve digestate dewaterability. The optimal conditions was at pH = 3, O=40 mg/g TS and PDS=0.1 g/g TS, under which the reductions in the normalized capillary suction time (NCST) and bound moisture (BM) of the FWD were 89.97% and 65.79%, respectively. Hydrophilic functional groups (oxygen- and nitrogen-containing groups) and hydrophilic protein molecular structures were decomposed by the reactive species of sulfate radical (SO·) and hydroxyl radicals (·OH) generated in the ozone-persulfate oxidation process, disrupting the binding between EPS and water molecules. The contributions of SO· and ·OH to digestate dewaterability were 42.51% and 28.55%. In addition, the introduction of H reduced electrostatic repulsion and contributed to the condensation of digestate flocs. The environmental implication assessment and economic analysis suggested that the O/PDS oxidation process was cost-effective and has a low environmental implication when applied to the FWD dewaterability improvement process. These results can serve as a reference for the management of FWD and further improvement of FWD treatment and disposal efficiency.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.jenvman.2024.120332 | DOI Listing |
Water Sci Technol
November 2024
Department of Civil and Environmental Engineering, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada.
A series of dewaterability tests were conducted on various types of sludges to establish a wholistic relationship between sludge water fractions. Sludge samples were obtained from batch and continuous sludge digesters, which were operated anaerobically and aerobically under mesophilic and thermophilic conditions. Dewaterability of the sludge samples and the distribution of water fractions were studied using centrifugation and thermal drying.
View Article and Find Full Text PDFWater Res
January 2025
Australian Centre for Water and Environmental Biotechnology, The University of Queensland, Brisbane, Queensland, Australia; Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, New South Wales 2052, Australia. Electronic address:
Integrated urban water management is an increasingly popular concept that cost-effectively maximizes system-wide performance by holistically considering all aspects of water and wastewater sectors. An innovative technology enabling production of high-quality bioenergy and an iron salt, ferrous carbonate (FeCO), represents a significant opportunity for integrated urban water management. This study experimentally evaluates the effect of in-sewer FeCO dosing on the performance of sewers and the downstream wastewater treatment plants.
View Article and Find Full Text PDFJ Environ Manage
October 2024
College of Petrochemical Engineering, Lanzhou University of Technology, Lanzhou, 730050, China.
J Environ Manage
September 2024
Department of Water Supply, Sanitation, and Environmental Engineering, IHE Delft Institute for Water Education, Westvest 7, 2611AX, Delft, the Netherlands.
In this study, cow manure was hydrothermally treated in a 2-litre reactor for 1 h at temperatures between 100 °C and 260 °C. Both the raw manure and the solid and liquid products of the hydrothermal treatment were characterized to understand the fate of the inorganic elements and to assess the suitability of the products for land applications and energy recovery. Satisfactory elemental balances were obtained for the organic and most inorganic elements and indicated that most inorganic elements were incorporated into the solids with lower solubility, with the exception of potassium and sodium, which were mostly solubilized in the process water; calcium and chlorine were also solubilized to a lesser extent in the process water.
View Article and Find Full Text PDFWater Sci Technol
August 2024
Kompetenzzentrum Wasser Berlin gGmbH, Grunewaldstraße 61-62, Berlin 10825, Germany.
An innovative circular economy (CE) system was implemented at the wastewater treatment plant (WWTP) in Brunswick. The performance of the CE system was evaluated for 4 years: the thermal pressure hydrolysis enhanced the methane production by 18% and increased the digestate dewaterability by 14%. Refractory COD formed in thermal hydrolysis and increased the COD concentration in the WWTP effluent by 4 mg L while still complying with the legal threshold.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!