Fate Of Natural Organic Matter Research Articles

Daughter oil droplet entrainment by oil-coated bubble bursting

Compound bubbles with a liquid coating in another continuous immiscible bulk phase are ubiquitous in a wide range of natural and industrial processes. Their formation, rise and ultimate bursting at the air–liquid interface play crucial roles in the transport and fate of natural organic matter and contaminants. However, the dynamics of compound bubbles has not received considerable attention until recently. Here, inspired by our previous work (Yang et al., Nat. Phys., vol. 19, 2023, pp. 884–890), we investigate the entrainment of daughter oil droplets in bulk water produced by a bursting oil-coated bubble. We document that the size of the entrained daughter oil droplet is affected by the oil coating fraction and the bulk liquid properties. We rationalize this observation by balancing the viscous force exerted by the extensional flow produced by bubble bursting with the capillary force resisting the deformation of the oil coating, and considering the subsequent end-pinching process which finally entrains the daughter oil droplets. We propose a scaling analysis for the daughter oil droplet size that well captures the experimental results for a wide range of oil coating fractions and Ohnesorge numbers of the bulk liquid. In addition, we discuss the non-monotonic variation of daughter droplet size with the Ohnesorge number, and show the eventual absence of daughter droplets because of the strong viscous effect in the high-Ohnesorge-number regime. Our findings may advance the fundamental understanding of compound bubble bursting and provide guidance and modelling constraints for bubble-mediated contaminant transport in liquids.

Deciphering the specific interaction of humic acid with divalent cations at the nanoscale

Humic acid (HA), a representative class of natural organic matter (NOM), can interact with a variety of divalent cations to form the metal-HA complexes, which is of vital significance in both the natural and engineered environments. To decipher the specific HA-divalent cation interaction mechanism, the intermolecular forces and adhesion energies between two HA surfaces in aqueous environment with varying divalent cations were directly quantified at the nanoscale using atomic force microscope (AFM). In the presence of Ca2+, the considerably increased HA aggregation and HA-Ca(II)-HA adhesion were detected with elevated Ca2+ concentration mainly due to the enhanced bridging effect, while the excessive amounts of Ca2+ could significantly suppress the aggregation and adhesion behavior. The adhesion energy was also found to be dependent on other aqueous conditions (e.g., pH, cation type), with the highest adhesion energy measured for Cu2+ (∼1.642 mJ m−2), approximately 2 ∼ 3-fold higher than the case of Zn2+ (∼0.950 mJ m−2), Ca2+ (∼0.829 mJ m−2) and Mg2+ (∼0.583 mJ m−2). Such robust adhesion for Cu2+ could stem from the synergistic bonding of Cu2+ with both the oxygen and amine sites of HA, which was evidently different from the single metal–oxygen bonding for Zn2+, Ca2+ and Mg2+ shown by X-ray photoelectron spectroscopy (XPS). Based on density functional theory (DFT) simulation, HA molecules could bridge with all these four types of divalent cations mainly by the deprotonated catechol and phthalic acid (PA) structures in the bidentate coordination mode, while the deprotonated aniline could only bond with Cu2+, ultimately leading to the highest Cu(II)-HA binding energy among the studied divalent cations. This work provides insights into the quantitative understanding of HA-divalent cation interaction mechanisms, shedding light on developing effective strategies to modulate the aggregation, transport and fate of NOM in aqueous environments as well as engineering applications.

Molecular-level characterization of natural organic matter in the reactive electrochemical ceramic membrane system for drinking water treatment using FT-ICR MS

Applications of electrochemical advanced oxidation processes are rising in drinking water treatment for effective mitigation of refractory organic compounds. This study explored the fate of natural organic matter (NOM) (lake water and standard NOM (SRNOM solution)) at molecular-level in the reactive electrochemical membrane (REM) system utilizing Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Fluorescence spectroscopy showed above 90 % removal of the humic-like component in both lake water and SRNOM solution in 10 min of REM operation compared to 70–80 % removal of the fulvic-like component after 30 min. REM-based treatment effectively eliminated (>70 %) the disinfection byproduct precursors. The lake water, sharing ~70 % of similar compounds with SRNOM, displayed a different propensity toward electrochemical oxidation, and its finished water was characterized with relatively lower double-bond equivalent (DBE), nominal oxidation state of carbon (NOSC), and aromaticity compared to that of SRNOM. The chloride ions in the water matrix of lake water impacted the electrochemical oxidation and generated significantly different transformation products than SRNOM solution. The heteroatoms (N and S) containing compounds (CHON and CHOS) were preferentially degraded in lake water; however, CHOS compounds were removed fewer in SRNOM. The electrosorption and electrochemical oxidation on the REM surface were the significant contributors for NOM removal. The newly formed compounds were mostly retained on the REM surface and fewer were released in finished water. This study is believed to help understand the fate of NOM in real source drinking water during electrochemical treatment.

A History of Molecular Level Analysis of Natural Organic Matter by FTICR Mass Spectrometry and The Paradigm Shift in Organic Geochemistry.

Natural organic matter (NOM) is a complex mixture of biogenic molecules resulting from the deposition and transformation of plant and animal matter. It has long been recognized that NOM plays an important role in many geological, geochemical, and environmental processes. Of particular concern is the fate of NOM in response to a warming climate in environments that have historically sequestered carbon (e.g., peatlands and swamps) but may transition to net carbon emitters. In this review, we will highlight developments in the application of high-field Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS) in identifying the individual components of complex NOM mixtures, focusing primarily on the fraction that is dissolved in natural waters (dissolved organic matter or DOM). We will first provide some historical perspective on developments in FTICR technology that made molecular-level characterizations of DOM possible. A variety of applications of the technique will then be described, followed by our view of the future of high-field FTICR MS in carbon cycling research, including a particularly exciting metabolomic approach.

Algal softening followed by ozonation: The fate of persistent micropollutants and natural organic matter in groundwater

A proof-of-concept study evaluates the performance of a novel strategy using photosynthetic microorganisms to soften groundwater instead of using caustic chemicals. The microalga Scenedesmus quadricauda was used to increase the pH of the groundwater via natural photosynthesis. This work applied softening as a pretreatment to ozonation of hard groundwater and mainly focused on investigating the multiple effects of algal softening on the degradation of persistent micropollutants upon subsequent ozonation. The algae-induced alkaline conditions (pH > 10) were favorable to catalyze the formation of OH radicals directly from O3 molecules. Moreover, algal softening removed the strong radical-scavenging carbonate species (HCO3− and CO32−) to a much greater extent than that achieved by chemical softening, which was attributed to the combination of mineral carbonation and metabolic CO2 reduction. The fate of the natural organic matter (NOM) was characterized with spectroscopy, chromatography, and bioassay, which indicates that algal treatment decomposed the NOM to be less susceptible to attack by OH radicals. Consequently, the ozonation of alkaline groundwater achieved a better removal of the micropollutant residues in groundwater. Carbamazepine and diclofenac were used as model chemicals of persistent groundwater contaminants and were almost completely removed with an addition of 1.25 mg O3 L−1 (0.63 mg-O3 mg-C−1).

Stable Mercury Isotope Transition during Postdepositional Decomposition of Biomass in a Forest Ecosystem over Five Centuries.

Organic soil is an important transient reservoir of mercury (Hg) in terrestrial ecosystems, but the fate of deposited Hg in organic forest soil is poorly understood. To understand the dynamic changes of deposited Hg on forest floor, the composition of stable Hg and carbon (C) isotopes in decomposing litters and organic soil layer was measured to construct the 500 year history of postdepositional Hg transformation in a subtropical evergreen broad-leaf forest in Southwest China. Using the observational data and a multiprocess isotope model, the contributions of microbial reduction, photoreduction, and dark reduction mediated by organic matter to the isotopic transition were estimated. Microbial reduction and photoreduction play a dominant role in the initial litter decomposition during first 2 years. Dark redox reactions mediated by organic matter become the predominant process in the subsequent 420 years. After that, the values of Hg mass dependent fractionation (MDF), mass independent fractionation (MIF), and Δ199Hg/Δ201Hg ratio do not change significantly, indicating sequestration and immobilization of Hg in soil. The linear correlations between the isotopic signatures of Hg and C suggest that postdepositional transformation of Hg is closely linked to the fate of natural organic matter (NOM). Our findings are consistent with the abiotic dark reduction driven by nuclear volume effect reported in boreal and tropical forests. We recommend that the dark reduction process be incorporated in future model assessment of the global Hg biogeochemical cycle.

Fate of natural organic matter and oxidation/disinfection by-products formation at a full-scale drinking water treatment plant

ABSTRACT This paper investigates the fate of natural organic matter (NOM) during the full-scale drinking water treatment plant supplied by Danube river bank filtration. After the recent reconstruction of the plant, special attention was devoted to the effects of ozone dose and granulated activated carbon (GAC) filtration on the formation and behaviour of oxidation by-products (carbonyl compounds and bromate), as well as carbonaceous and nitrogenous chlorination by-products. For the oxidation of aromatic NOM moieties that absorb light at UV254, a lower ozone dose (1.0 g O3/m3) is sufficient, whereas to achieve a measurable reduction (about 20%) of total organic carbon, an ozone dose of 1.5 g O3/m3 is required. The content of carbonyl compounds in the water after ozonation increases relative to the content before oxidation treatment, and is up to 12 times higher in the case of aldehydes and up to 2 times higher in the case of carboxylic acids. Seasonal variations, including changes in temperature and the amount of precipitation, were also shown to affect the content of organic matter in the raw water, with slight effects on the quality of the treated water. In the winter, the organic matter content is slightly higher, meaning their transformation products aldehydes and carboxylic acids, are also higher during the winter than the summer.

Investigating the fate of natural organic matter at a drinking water treatment plant in South Africa using optical spectroscopy and chemometric analysis

The removal dynamics of biodegradable dissolved organic carbon (BDOC) and natural organic matter (NOM) polarity fractions at a water treatment plant (WTP) in South Africa was studied using UV-Vis absorbance, fluorescence excitation-emission matrix, and two-dimensional synchronous fluorescence spectroscopy (SFS). This study gave insights into the transformation of NOM due to treatment processes. The objectives of the study were: (i) to use chemometric analysis and two-dimensional SFS correlations to investigate the evolution of NOM arising from treatment processes, and (ii) to access the chemical profile dynamics of polarity and BDOC fractions throughout the treatment train. The UV254 absorbance, which indicates aromaticity, reduced by 45% along the WTP. Gaussian fitting of UV-Vis data showed a decreasing trend in intensity and number of bands along the treatment process. The removal efficiency of NOM components followed the order: humic-like (HL) > tyrosine-like (TYL) > fulvic-like (FL) > tryptophan-like (TPL) > microbial-like (MBL). At the source, the relative distribution of the hydrophobic (HPO), hydrophilic (HPI), and transphilic (TPI) fractions was 45%, 31%, and 24%, respectively. The HPI was recalcitrant to treatment, and the TYL component of the HPI fraction was conjectured to be a disinfection byproduct limiting reagent. The HL and FL components of the BDOC fraction were the major substrates for bacterial growth. According to two-dimensional-SFS correlation, TYL, TPL, and MBL varied concurrently across the treatment stages. Used for the first time in South Africa, the robustness of a multi-dimensional approach of optical methods coupled with chemometric tools for the assessment of the fate of NOM along the treatment processes was revealed by this study.

Quantitation of amino sugar stereoisomer and muramic acid biomarkers by hydrophilic interaction liquid chromatography-mass spectrometry

A rapid separation and quantitation of the stereoisomer amino sugars glucosamine, galactosamine, and mannosamine, along with muramic acid, is needed. These compounds, when their quantities are accurate, can be used to understand the origin and fate of natural organic matter (NOM) in the environment. These target molecules are biomarkers of fungi and bacteria and allow the deconvolution of microbial transformations and degradation of NOM in a wide variety of environmental matrices. Analytical methods applied to this suite of biomarkers are needed to understand carbon and nitrogen biogeochemistry with a changing global climate. Traditional separations of these analytes by gas chromatography require sample derivatization, as does reverse phase liquid chromatography. In contrast, ion chromatography can separate the analytes directly, but requires a separate analytical method to quantify muramic acid. In this work we present a direct analysis of all these molecules using hydrophilic liquid interaction chromatography. Solvent composition, buffer strength, pH, flow rate, and column temperature were optimized. The method can separate these four compounds and the biopolymeric precursor molecule N-acetylglucosamine in a single run in under 8 min with equivalent resolution to the best previously reported separations that did not require derivatization prior to analysis. Detection of the analytes was performed by both tandem and time-of-flight mass spectrometry. The method was assessed for its quantitative capabilities through i) peak area assignment, ii) check standards with ratios of the target analytes likely to be present in real samples, iii) an injection internal standard, and iv) quantitative analysis of real soil hydrolysates by external calibration and standard addition approaches. Across their expected analytical ranges the response for each analyte was highly linear with good accuracy (<25%) and precision (<15%) over three orders of magnitude. Detection limits of 20 µg L−1 were found for galactosamine and 5 µg L−1 for the remainder of the analytes, comparable to the majority of other methods reported in the literature. Overall, this new approach can directly and rapidly quantify amino sugars recovered in environmental hydrolysates.

The properties and removal efficacies of natural organic matter fractions by South African drinking water treatment plants

This study presents an investigation on the fate of natural organic matter (NOM) and its dynamics throughout the treatment train at various drinking water treatment plants (WTP) in South Africa. The characteristics, concentration and removal efficiencies of NOM at various treatment stages on the basis of dissolved organic carbon, UV absorbance, specific ultra-violet absorbance, spectroscopic indices, maximum fluorescence intensity (Fmax), and polysaccharides removal, were studied. The highest polysaccharide concentration was in coastal plants compared to inland plants for the raw water samples. A Parafac model fitting four components was established for the raw waters, and validated based on the split half criteria. The Fmax values of the components was higher for terrestrial humic-like component (C1) and fulvic-like component (C2) than for humic-like components (C3), and for protein-like component (C4). Strikingly, the mean Fmax values for C2 and C3 were higher for plants located on the south west coast of South Africa than the plants located inland. While the humification index and UV254 removal correlated (R2 = 0.797), the correlation between the freshness index (β:α) and UV254 removal was also mild (R2 = 0.787). The removal efficiencies of bulk NOM were higher than for FNOM in the rapid sand filtration (RSF) stage, regardless of the location of the plants, suggesting that the RSF process is more efficient in removing non-fluorescent NOM than FNOM fractions. This study demonstrated the capability of optical methods in characterizing the fate, occurrence and removal of NOM in surface waters.

Characteristics and fate of natural organic matter during UV oxidation processes

Advanced oxidation processes (AOPs) are widely used in water treatments. During oxidation processes, natural organic matter (NOM) is modified and broken down into smaller compounds that affect the characteristics of the oxidized NOM by AOPs. In this study, NOM was characterized and monitored in the UV/hydrogen peroxide (H2O2) and UV/persulfate (PS) processes using a liquid chromatography–organic carbon detector (LC-OCD) technique, and a combination of excitation–emission matrices (EEM) and parallel factor analysis (PARAFAC). The percentages of mineralization of NOM in the UV/H2O2 and UV/PS processes were 20.5 and 83.3%, respectively, with a 10 mM oxidant dose and a contact time of 174 s (UV dose: approximately 30,000 mJ). Low-pressure, Hg UV lamp (254 nm) was applied in this experiment. The steady-state concentration of SO4− was 38-fold higher than that of OH at an oxidant dose of 10 mM. With para-chlorobenzoic acid (pCBA) as a radical probe compound, we experimentally determined the rate constants of Suwannee River NOM (SRNOM) with OH (kOH/NOM = 3.3 × 108 M−1s−1) and SO4− (kSO4-/NOM = 4.55 × 106 M−1s−1). The hydroxyl radical and sulfate radical showed different mineralization pathways of NOM, which have been verified by the use of LC-OCD and EEM/PARAFAC. Consequently, higher steady-state concentrations of SO4−, and different reaction preferences of OH and SO4− with the NOM constituent had an effect on the mineralization efficiency.

Fate of natural organic matter at a full-scale Drinking Water Treatment Plant in Greece.

The aim of this study was to investigate the fate of natural organic matter (NOM) and subsequent changes during the various treatment processes at a full-scale Drinking Water Treatment Plant (DWTP). Monthly sampling campaigns were conducted for 1 year at six sites along DWTP of Thessaloniki, Northern Greece including raw water from the Aliakmonas River that supplies DWTP and samples from various treatment processes (pre-ozonation, coagulation, sand filtration, ozonation, and granular activated carbon (GAC) filtration). The concentration of NOM and its characteristics as well as the removal efficiency of various treatment processes on the basis of dissolved organic carbon, UV absorbance, specific ultra-violet absorbance, fluorescence intensity, hydrophobicity, biodegradable dissolved organic carbon, and formation potential of chlorination by-products trihalomethanes (THMs) and haloacetic acids (HAAs) were studied. The concentration of dissolved organic carbon (DOC) in reservoir of the Aliakmonas River ranged from 1.46 to 1.84 mg/L, exhibiting variations regarding UV, fluorescence, and hydrophobic character through the year. Along DWTP, a significant reduction of aromatic, fluorophoric, and hydrophobic character of NOM was observed resulting in significant elimination of THM (63%) and HAAs (75%) precursors.

The fate of natural organic matter during UV/H2O2 advanced oxidation of drinking water

At conditions within the range of those typically applied for commercial drinking water applications, the impact of ultraviolet and hydrogen peroxide (UV/H2O2) advanced oxidation (AO) on the concentration, spectral characteristics, hydrophobicity, and biodegradability of natural organic matter (NOM) in a raw surface water and ultrafiltered surface water was studied. At an initial H2O2 dose of 20 mg L−1, UV/H2O2 mineralized less than 15% of the NOM in raw surface water at a fluence of 1500 mJ cm−2. Natural organic matter in ultrafiltered surface water was mineralized by at least 27% after about 1500 mJ cm−2. Partial oxidation of NOM led to ring opening of aromatic structures, cleavage of conjugated double bonded carbon structures, and reduction in the degree of aromatic substitution. The UV/H2O2 AO preferentially reacted with hydrophobic fractions of NOM leading to the formation of hydrophilic products. The treatment oxidized recalcitrant NOM into more readily biodegradable compounds with significant increases in formaldehyde and acetaldehyde concentrations. Depending on NOM properties for a given water, UV/H2O2 AO may cause partial oxidation of NOM leading to the formation of biodegradable compounds. The presence of these species may need to be addressed with a downstream process capable of improving biological stability.

The fate of natural organic matter during UV/H2O2 advanced oxidation of drinking waterA paper submitted to the Journal of Environmental Engineering and Science.

At conditions within the range of those typically applied for commercial drinking water applications, the impact of ultraviolet and hydrogen peroxide (UV/H2O2) advanced oxidation (AO) on the concentration, spectral characteristics, hydrophobicity, and biodegradability of natural organic matter (NOM) in a raw surface water and ultrafiltered surface water was studied. At an initial H2O2 dose of 20 mg L–1, UV/H2O2 mineralized less than 15% of the NOM in raw surface water at a fluence of 1500 mJ cm–2. Natural organic matter in ultrafiltered surface water was mineralized by at least 27% after about 1500 mJ cm–2. Partial oxidation of NOM led to ring opening of aromatic structures, cleavage of conjugated double bonded carbon structures, and reduction in the degree of aromatic substitution. The UV/H2O2 AO preferentially reacted with hydrophobic fractions of NOM leading to the formation of hydrophilic products. The treatment oxidized recalcitrant NOM into more readily biodegradable compounds with significant increases in formaldehyde and acetaldehyde concentrations. Depending on NOM properties for a given water, UV/H2O2 AO may cause partial oxidation of NOM leading to the formation of biodegradable compounds. The presence of these species may need to be addressed with a downstream process capable of improving biological stability.

Seasonal variations of disinfection by-product precursors profile and their removal through surface water treatment plants

A sampling program has been undertaken to investigate the variations of disinfection by-products (DBPs) formation and nature and fate of natural organic matter (NOM) through water treatment plants in Istanbul. Specific focus has been given to the effect seasonal changes on the formation of DBPs and organic precursors levels. Water samples were collected from the three reservoirs inlet and within three major water treatment plants of Istanbul, Turkey. Changes in the dissolved organic carbon (DOC), ultraviolet absorbance at 254 nm (UV 254), specific ultraviolet absorbance (SUVA), trihalomethane formation potential (THMFP), and haloacetic acids formation potential (HAAFP) were measured for both the treated and raw water samples. The variations of THM and HAA concentrations within treatment processes were monitored and also successfully assessed. The reactivity of the organic matter changed throughout the year with the lowest reactivity (THMFP and HAAFP) in winter, increasing in spring and reaching a maximum in fall season. This corresponded to the water being easier to treat in fall and an increase in the proportion of hydrophobic content. Understanding the seasonal changes in organic matter character and their reactivity with treatment chemicals should lead to a better optimization of the treatment processes and a more consistent water quality.

The effect of cadmium on fulvic acid adsorption to Bacillus subtilis

The effects of Cd on the adsorption of an aquatic fulvic acid (FA) to the surface of Bacillus subtilis were investigated from pH 2.5 to 7.0, at fixed ionic strength (0.1 M NaClO 4) and at ambient temperature (∼22 °C). Cd (14 mg/l) had no effect on FA adsorption at pH<5 but increased FA adsorption at pH>6. The effects of Cd (0, 14 mg/l) on FA adsorption to B. subtilis were further examined as a function of initial FA concentration (0–45 mg C/l) at pH 6.5. FA adsorption isotherms also were measured at pH 6.5 as a function of dissolved Cd concentration (0–14 mg/l) at three initial FA concentrations (4, 8, 22 mg C/l). At all FA concentrations studied at pH 6.5, FA adsorption increased with increasing initial total Cd concentration. Under all studied conditions, preferential adsorption of high- to intermediate-molecular-weight FA components to B. subtilis resulted in a fractionation of the FA pool, with lower-molecular-weight components remaining in solution. At pH>6, Cd further enhanced the adsorption of high- to intermediate-molecular-weight FA components but did not significantly enhance the adsorption of lower-molecular-weight components. Hence, the overall process of adsorptive fractionation was not altered significantly by the presence of Cd. Overall, the results of this study (1) demonstrate that FA adsorption to bacterial surfaces can be altered by the presence of a metal cation, and (2) provide further evidence that microbe–metal–ligand interactions may significantly affect the mobility and fate of natural organic matter in the subsurface.

Seasonal variations in the disinfection by-product precursor profile of a reservoir water

Research Article| December 01 2002 Seasonal variations in the disinfection by-product precursor profile of a reservoir water Emma H. Goslan; Emma H. Goslan 1School of Water Sciences, Cranfield University, Cranfield, Bedfordshire MK43 0AL, UK Search for other works by this author on: This Site PubMed Google Scholar David A. Fearing; David A. Fearing 1School of Water Sciences, Cranfield University, Cranfield, Bedfordshire MK43 0AL, UK Search for other works by this author on: This Site PubMed Google Scholar Jenny Banks; Jenny Banks 2Water Quality Technology Development Department, Yorkshire Water, Western Way, Halifax Road, Bradford, BD6 2LZ, UK Search for other works by this author on: This Site PubMed Google Scholar Derek Wilson; Derek Wilson 2Water Quality Technology Development Department, Yorkshire Water, Western Way, Halifax Road, Bradford, BD6 2LZ, UK Search for other works by this author on: This Site PubMed Google Scholar Peter Hills; Peter Hills 3United Utilities Service Delivery, Asset Creation—Task Team, Thirlmere House, Lingley Mere, Lingley Green Avenue, Warrington, WA5 3LP, UK Search for other works by this author on: This Site PubMed Google Scholar Andrew T. Campbell; Andrew T. Campbell 3United Utilities Service Delivery, Asset Creation—Task Team, Thirlmere House, Lingley Mere, Lingley Green Avenue, Warrington, WA5 3LP, UK Search for other works by this author on: This Site PubMed Google Scholar Simon A. Parsons Simon A. Parsons 1School of Water Sciences, Cranfield University, Cranfield, Bedfordshire MK43 0AL, UK Fax: +44 1234 751671; E-mail: s.a.parsons@cranfield.ac.uk Search for other works by this author on: This Site PubMed Google Scholar Journal of Water Supply: Research and Technology-Aqua (2002) 51 (8): 475–482. https://doi.org/10.2166/aqua.2002.0041 Article history Received: August 16 2001 Accepted: July 30 2002 Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Share Icon Share Twitter LinkedIn Tools Icon Tools Cite Icon Cite Permissions Search Site Search Dropdown Menu nav search search input Search input auto suggest search filter All ContentAll JournalsThis Journal Search Advanced Search Citation Emma H. Goslan, David A. Fearing, Jenny Banks, Derek Wilson, Peter Hills, Andrew T. Campbell, Simon A. Parsons; Seasonal variations in the disinfection by-product precursor profile of a reservoir water. Journal of Water Supply: Research and Technology-Aqua 1 December 2002; 51 (8): 475–482. doi: https://doi.org/10.2166/aqua.2002.0041 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex A sampling programme has been undertaken to investigate the nature and fate of natural organic matter (NOM) through a water treatment works (WTW). Specific focus has been given to the effect seasonal changes have on NOM. Water samples were collected from the reservoir inlet and after the filters at Albert WTW in Yorkshire. Samples were taken in January, June and November 2000. Changes in the dissolved organic carbon (DOC), ultra-violet (UV) absorbance at 254 nm, specific UV absorbance (SUVA) and trihalomethane formation potential (THM-FP) were measured for both the filtered and raw water. The waters were fractionated by XAD resin adsorption techniques into hydrophobic acid (HPO-A) and hydrophilic acid (HPI-A) fractions. The fractions were analysed for DOC, UV, SUVA and THM-FP. The reactivity of the fractions changed throughout the year with the lowest reactivity (THM-FP) in January, increasing in June and reaching a maximum in November. This corresponded to the water being more difficult to treat in November and an increase in the proportion of hydrophobic acid. Information was obtained through the fractionation that would be impossible to predict from only the bulk water parameters. characterisation, disinfection by-products, fractionation, natural organic matter This content is only available as a PDF. © IWA Publishing 2002 You do not currently have access to this content.

Fate of Natural Organic Matter (NOM) during Groundwater Recharge using Reclaimed Water

The scope of this study was to investigate how natural organic matter (NOM) from drinking water and soluble microbial products (SMP) generated in the wastewater treatment process influence the character of DOC in reclaimed water used for indirect potable reuse. Biodegradation studies in conjunction with XAD-fractionation and 13C-NMR spectroscopy were applied to both characterize organic matter and to study removal mechanisms during subsequent soil-aquifer treatment (SAT). Based on hydraulically corresponding samples of drinking water and reclaimed water from reuse sites in Arizona and California, residual DOC in reclaimed water after SAT was dominated in concentration and character by NOM. Changes in DOC character were observed with increasing retention times during SAT in the direction to more aliphatic and less aromatic compounds indicative of humification with biodegradation as the dominant transformation process for bulk organics.

Fate of natural organic matter (NOM) during ground water recharge using reclaimed water

The scope of this study was to investigate how natural organic matter (NOM) from drinking water and soluble microbial products (SMP) generated in the wastewater treatment process influence the character of DOC in reclaimed water used for indirect potable reuse. Biodegradation studies in conjunction with XAD-fractionation and 13 C-NMR spectroscopy were applied to both characterize organic matter and to study removal mechanisms during subsequent soil-aquifer treatment (SAT). Based on hydraulically corresponding samples of drinking water and reclaimed water from reuse sites in Arizona and California, residual DOC in reclaimed water after SAT was dominated in concentration and character by NOM. Changes in DOC character were observed with increasing retention times during SAT in the direction to more aliphatic and less aromatic compounds indicative of humification with biodegradation as the dominant transformation process for bulk organics.

Modeling of natural organic matter transport processes in groundwater.

A forced-gradient tracer test was conducted at the Georgetown site to study the transport of natural organic matter (NOM) in groundwater. In particular, the goal of this experiment was to investigate the interactions between NOM and the aquifer matrix. A detailed three-dimensional characterization of the hydrologic conductivity heterogeneity of the site was obtained using slug tests. The transport of a conservative tracer (chloride) was successfully reproduced using these conductivity data. Despite the good simulation of the flow field, NOM breakthrough curves could not be reproduced using a two-site sorption model with spatially constant parameters. Preliminary results suggest that different mechanisms for the adsorption/desorption processes, as well as their spatial variability, may significantly affect the transport and fate of NOM.