The aim of this research was to better understand chemical pre-treatment of combined sewer overflows (CSOs) for subsequent ultraviolet (UV) disinfection. Approximately 200 jar tests were completed. Alum (Al2(S04)3·12H2O) resulted in a higher UV light transmission (UVT), and equivalent total suspended solids (TSS) removal, than ferric chloride (FeCl3). An alum dose of 20 mg/L increased the UVT of the raw CSO from 30 to 60% after settling. The addition of 100 mg/L of alum maximized UVT reaching approximately 85%. Flocculation did not increase UVT. However, it did improve the removal of TSS. Cationic polymers worked quickly compared with metal coagulants, but only reached a UVT of 60%. A high positive charge density on the polymer improved the removal of turbidity when compared with low charge, but did not affect UVT. If the goal is to maximise UVT, a very high alum dose may be preferred. If the goal is to minimize coagulant dose with moderate UV performance, cationic polymer at approximately 3 mg/L is recommended.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.2166/wst.2015.447 | DOI Listing |
Sci Total Environ
January 2025
Department of Science and Engineering of Materials, Environment and Urban Planning - SIMAU, Polytechnic University of Marche, via Brecce Bianche 12, 60131 Ancona, Italy.
The reuse of stormwater represents a potential option for meeting water demands in water stressed regions as well as preventing and mitigating diffuse pollution of receiving water bodies. Particularly, the elaboration of a risk management plan for stormwater reuse may help to understand associated environmental and public health risks and design fit-for-purpose water treatment processes. In this work, it is presented an innovative methodology to perform quantitative microbial risk assessment (QMRA) for stormwater reuse by using data simulated by SWMM software.
View Article and Find Full Text PDFSci Total Environ
January 2025
Leibniz Universität Hannover, 30459 Hannover, Germany. Electronic address:
With the beginning of the COVID-19 pandemic, wastewater-based epidemiology (WBE), which according to Larsen et al. (2021), describes the science of linking pathogens and chemicals found in wastewater to population-level health, received an enormous boost worldwide. The basic procedure in WBE is to analyse pathogen concentrations and to relate these measurements to cases from clinical data.
View Article and Find Full Text PDFWater Res
March 2025
Faculty of Engineering, Institute of Environmental and Process Engineering, RheinMain University of Applied Sciences, Wiesbaden, Germany.
Although the paper industry processes polymeric materials and discharges large amounts of wastewater, no research on microplastics in the wastewater from paper mills has been published to date. This study is the first to investigate this issue. The wastewater treatment plants of twelve representatively selected German paper mills were investigated using an analysis protocol based on µ-Raman spectroscopy.
View Article and Find Full Text PDFWater Res X
January 2025
Department of Systemic Environmental Biotechnology, Helmholtz Centre for Environmental Research-UFZ, Permoserstrasse 15 04318 Leipzig, Germany.
Due to accelerating climate change and the need for new development to accommodate population growth, adaptation of urban drainage systems has become a pressing issue in cities. Questions arise whether decentralised urban drainage systems are a better alternative to centralised systems, and whether Nature Based Solutions' (NBS) multifunctionality also brings economic benefits. This research aims to develop spatio-economic scenarios to support cities in increasing their resilience to urban flooding with NBS.
View Article and Find Full Text PDFEnviron Res
December 2024
Laboratory of Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, 100871, Beijing, PR China. Electronic address:
At the end of 2022, a sudden policy shift in China triggered an unprecedented COVID-19 outbreak that led to a dramatic increase in the consumption of antipyretics. In this study, the occurrence of the two most commonly used antipyretics (ibuprofen and paracetamol) and their metabolites were analyzed in the wastewater of nine major cities in China, covering the periods before, during, and after the policy change. The remarkable surge after the policy change for ibuprofen and paracetamol reached 67 times (in Nanning) and 311 times (in Lanzhou) compared to pre-pandemic levels, respectively.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!