Photodegradation-induced biological degradation of treated wastewater effluent organic matter in receiving waters

The reuse of treated wastewater to augment natural drinking water supplies is receiving serious consideration. Treatment of secondary and tertiary effluent by membrane filtration was investigated by assessing nanofiltration (NF) membrane and ultrafiltration (UF) membranes in bench-scale experiments. It was found that secondary and tertiary effluent contained high concentration of effluent organic matter (EfOM), contributing EfOM-related fouling. Flux decline and EfOM rejection tests were evaluated, using a dead-end stirred cell filtration unit. Surface charge and molecular weight cut-off (MWCO) of membranes were significant factors in membrane performance including permeability and EfOM-rejection.

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Characterization of wastewater effluent organic matter with different solid phase extraction sorbents

Chemosphere ◽

10.1016/j.chemosphere.2020.127235 ◽

2020 ◽

Vol 257 ◽

pp. 127235

Author(s):

Xin Wang ◽

Yuanyuan Ji ◽

Quan Shi ◽

Yahe Zhang ◽

Chen He ◽

...

Keyword(s):

Organic Matter ◽

Solid Phase Extraction ◽

Solid Phase ◽

Wastewater Effluent ◽

Phase Extraction ◽

Effluent Organic Matter

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Fouling of low-pressure (MF and UF) membranes by wastewater effluent organic matter (EfOM): characterization of EfOM foulants in relation to membrane properties

Water Science & Technology Water Supply ◽

10.2166/ws.2003.0172 ◽

2003 ◽

Vol 3 (5-6) ◽

pp. 229-235 ◽

Cited By ~ 2

Author(s):

C. Laabs ◽

G. Amy ◽

M. Jekel ◽

H. Buisson

Keyword(s):

Organic Matter ◽

Wastewater Treatment ◽

Treatment Plant ◽

Low Pressure ◽

Wastewater Effluent ◽

Membrane Properties ◽

Feed Water ◽

Effluent Organic Matter ◽

Efficient Operation ◽

Atomic Force

Low-pressure (micro- and ultrafiltration) membranes are increasingly being used in water reclamation processes treating secondary or tertiary effluent from wastewater treatment plants. The main challenge remains the fouling of membrane surface/pores by organic matter which prevents efficient operation. The extent of this fouling strongly depends on feed water quality as well as membrane properties. The aim of this study is to characterize wastewater effluent organic matter (EfOM) and to describe its fouling behavior in relation to various membrane properties (pore size, charge, material, hydrophobicity) through evaluation with stirred cell experiments, elemental analysis, 13C-NMR spectroscopy, and atomic force spectroscopy. Four membranes are tested - one ultrafiltration (UF) membrane and three microfiltration (MF) membranes - with bulk EfOM, derived from the Boulder, Colorado, USA, wastewater treatment plant, as well as with EfOM isolates. The hydrophobic microfiltration membrane is most seriously fouled by bulk Boulder EfOM, while the two hydrophilic membranes (MF, UF) made of cellulose acetate are the least fouled. Differences between the flux decline curves of various membranes are less distinct with isolates than with bulk EfOM. The transphilic isolate (TPIA-Bld) exhibited a higher fouling potential than the hydrophobic isolate (HPOA-Bld). This behaviour is due to the different chemical characteristics of the isolates, namely the higher percentage of hetero-atoms (oxygen and nitrogen) of the transphilic isolate compared to the hydrophobic isolate. Finally, atomic force microscope (AFM) images present clear evidence of fouling. AFM is clearly able to detect the fouling layer, although it has not been possible to distinguish between pore blockage and surface fouling thus far.

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Fate of effluent organic matter (EfOM) and natural organic matter (NOM) through riverbank filtration

Water Science & Technology ◽

10.2166/wst.2008.613 ◽

2008 ◽

Vol 57 (12) ◽

pp. 1999-2007 ◽

Cited By ~ 31

Author(s):

S. K. Maeng ◽

S. K. Sharma ◽

A. Magic-Knezev ◽

G. Amy

Keyword(s):

Organic Matter ◽

Surface Water ◽

Natural Organic Matter ◽

Wastewater Effluent ◽

Riverbank Filtration ◽

Soil Columns ◽

Effluent Organic Matter ◽

Bulk Organic Matter ◽

Water And Wastewater ◽

The Impact

Understanding the fate of effluent organic matter (EfOM) and natural organic matter (NOM) through riverbank filtration is essential to assess the impact of wastewater effluent on the post treatment requirements of riverbank filtrates. Furthermore, their fate during drinking water treatment can significantly determine the process design. The objective of this study was to characterise bulk organic matter which consists of EfOM and NOM during riverbank filtration using a suite of innovative analytical tools. Wastewater effluent-derived surface water and surface water were used as source waters in experiments with soil columns. Results showed the preferential removal of non-humic substances (i.e. biopolymers) from wastewater effluent-derived surface water. The bulk organic matter characteristics of wastewater effluent-derived surface water and surface water were similar after 5 m soil passage in laboratory column experiment. Humic-like organic matter in surface water and wastewater effluent-derived surface water persisted through the soil passage. More than 50% of total dissolved organic carbon (DOC) removal with significant reduction of dissolved oxygen (DO) was observed in the top 50 cm of the soil columns for both surface water and wastewater effluent-derived surface water. This was due to biodegradation by soil biomass which was determined by adenosine triphosphate (ATP) concentrations and heterotrophic plate counts. High concentrations of ATP in the first few centimeters of infiltration surface reflect the highest microbial activity which correlates with the extent of DOC reduction. Good correlation of DOC removal with DO and biomass development was observed in the soil columns.

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Photo-Transformation of Effluent Organic Matter by ZnO-Based Sunlight Irradiation

Applied Sciences ◽

10.3390/app10249002 ◽

2020 ◽

Vol 10 (24) ◽

pp. 9002

Author(s):

Thao Thi Nguyen ◽

Seong Nam Nam ◽

Jeill Oh

Keyword(s):

Organic Matter ◽

Photocatalytic Degradation ◽

Removal Efficiency ◽

Treatment Plant ◽

Wastewater Effluent ◽

Solar Irradiation ◽

Effluent Organic Matter ◽

Sunlight Irradiation ◽

Vis Spectroscopy ◽

The Impact

This study investigated the impact of effluent organic matter (EfOM) from wastewater effluent on the properties of organic matter in receiving water and the efficiency of its removal using photocatalysis. The organic matter is characterized using fluorescence excitation-emission matrices coupled with parallel factor analysis (EEM-PARAFAC), UV-Vis spectroscopy, and dissolved organic carbon (DOC) measurements. The experiments are conducted with water samples that were collected from upstream waters (used as a source of dissolved organic matter (DOM)), wastewater effluent (a source of EfOM), and waters downstream of a wastewater treatment plant, and with upstream water and wastewater effluent being mixed at different ratios in the lab (DOM/EfOM). EEM-PARAFAC analysis identifies three components: a humic-like component (C1), a tyrosine-like component (C2), and a terrestrial-like humic component (C3). When compared to DOM, EfOM has a higher specific ultraviolet absorbance at 254 nm (SUVA254), a higher fluorescence index (FI), and more abundant humic-like components. As the EfOM contribution increased, an increase in both humic-like components and a simultaneous decrease in the protein-like components are observed. The photocatalytic degradation of the organic matter using simulated solar irradiation with ZnO as a catalyst is examined. The removal efficiency of photocatalysis is calculated using the DOC, UV absorbance at 254 nm (UV254), and the maximum fluorescence intensity (Fmax) of the PARAFAC components. After 120 min of irradiation, the removal efficiency of photocatalysis differs between the DOM, EfOM, and EfOM-impacted samples due to the change in the properties of the organic matter in the source water. The photocatalytic degradation of organic matter follows pseudo-first-order kinetics, with the DOC and UV254 exhibiting a lower removal efficiency with the increasing contribution of EfOM, which indicated that EfOM has a potentially negative impact on the performance of drinking water treatment. The removal of PARAFAC components follows the order C3 > C1 > C2, indicating that humic-like components are preferentially removed when compared to protein-like components under sunlight irradiation.

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