| Title |
Re-flocculation reduces the effectiveness of sewage sludge pretreatment through hydrodynamic disintegration prior to anaerobic digestion |
| ID_Doc |
26883 |
| Authors |
Garlicka, A; Kupidura, P; Krawczyk, P; Umiejewska, K; Muszynski, A |
| Title |
Re-flocculation reduces the effectiveness of sewage sludge pretreatment through hydrodynamic disintegration prior to anaerobic digestion |
| Year |
2023 |
| Published |
|
| DOI |
10.1016/j.chemosphere.2023.138522 |
| Abstract |
Circular economy model, based on the "make, use, reuse, remake, recycle" approach, is an alternative to progressive depletion of non-renewable fossil fuels. Sewage sludge can be a source of renewable energy obtained through the anaerobic conversion of their organic fraction into biogas. This process is mediated by highly complex microbial communities and its efficiency depends on the availability of substrates to microorganisms. Disintegration of the feedstock in the pre-treatment step may intensify the anaerobic digestion, but reflocculation of disintegrated sludge (reassembly of the released fractions into larger agglomerates) may result in a reduced availability of the released organic compounds for microbes. Pilot-scale studies on re-flocculation of disintegrated sludge were conducted to select parameters for scaling-up the pre-treatment and intensifying the anaerobic digestion process in two large Polish wastewater treatment plants (WWTPs). Samples of thickened excess sludge from full-scale WWTPs were subjected to hydrodynamic disintegration at three energy density levels of 10 kJ/L, 35 kJ/L and 70 kJ/L. Microscopic analyses of disintegrated sludge samples were carried out twice: i) immediately after the disintegration process at a given energy density level, ii) and after 24-h incubation at 4 degrees C following the disintegration. Micro-photographs of 30 randomly selected fields of view were taken for each analysed sample. A method of the image analysis was developed as a tool to measure dispersion of sludge flocs to assess the re-flocculation degree. Re-flocculation of the thickened excess sludge occurred within 24 h |
| Author Keywords |
Renewable energy; Anaerobic digestion; Sludge pre-treatment; Hydrodynamic disintegration; Sludge re-flocculation; Image analysis |
| Index Keywords |
Index Keywords |
| Document Type |
Other |
| Open Access |
Open Access |
| Source |
Science Citation Index Expanded (SCI-EXPANDED) |
| EID |
WOS:000984273400001 |
| WoS Category |
Environmental Sciences |
| Research Area |
Environmental Sciences & Ecology |
| PDF |
https://doi.org/10.1016/j.chemosphere.2023.138522
|