The formation of disinfection by-products (DBPs) in drinking water has become an issue of greater concern in recent years. Bench-scale jar tests were conducted on a surface water to evaluate the impact of enhanced coagulation on the removal of organic DBP precursors and the formation of trihalomethanes (THMs) and haloacetic acids (HAAs). The results of this testing indicate that enhanced coagulation practices can improve treated water quality without increasing coagulant dosage. The data generated were also used to develop artificial neural networks (ANNs) to predict THM and HAA formation. Testing of these models showed high correlations between the actual and predicted data. In addition, an experimental plan was developed to use ANNs for treatment optimization at the Peterborough pilot plant.

Quantification of natural organic matter (NOM) in water is limited by the complex and varied nature of compounds found in natural waters. Current characterization techniques, which identify and quantify fractions of NOM, are often expensive and time consuming suggesting the need for rapid and accurate characterization methods. In this work, principal component analysis of fluorescence excitation-emission matrices (FEEM-PCA) was investigated as a NOM characterization technique. Through the use of jar tests and disinfection by-product formation tests, FEEM-PCA was shown to be a good surrogate for disinfection by-product precursors. FEEM-PCA was also applied in order to characterize differences in humic-like, protein-like, and Rayleigh scattering between multiple source waters and due to differing treatment processes. A decrease in Rayleigh scattering influence was observed for a deep lake intake, and multiple processes were found to significantly affect humic-like substances, protein-like, and Rayleigh scattering fractions.

N-nitrosamines are considered as a group of emerging disinfection byproducts (DBPs) with potential carcinogenicity at ng/L level. The presence of nitrosamines in drinking water is most commonly associated with chloramination of amine-based precursors. This research investigates the potential of amine-based pharmaceuticals and personal care products (PPCPs) as nitrosamine precursors under practical drinking water disinfection conditions, as well as some critical factors that may affect the nitrosamine formation via PPCPs. All of the twenty selected PPCPs were able to form the corresponding nitrosamines upon chloramine disinfection, and eight of them rendered molar conversions higher than 1 % under practical disinfection conditions. Ranitidine had the highest N-nitrosodimethylamine (NDMA) molar conversion among the tested PPCPs. A three-parameter kinetic model was proposed to describe and predict the NDMA formation from pharmaceuticals during chloramination in various water matrices. The model accurately reflected all three significant characteristics of the NDMA formation curve, including an initial lag phase, followed by a fast increase in NDMA formation, and eventually reaching a plateau. In lab-grade water, the NDMA formation from pharmaceuticals was affected by the Cl2:NH4-N mass ratio, pH, and prechlorination. The NDMA formation increased with the Cl2:NH4-N mass ratio, indicating an enhancement effect of dichloramine. The pH affected both the ultimate NDMA conversion and the reaction rate. The reaction rate is mainly determined by the level of non-protonated amine species, and it increased consistently with increasing pH. The ultimate NDMA conversion is limited by the level of dichloramine, and the maximum NDMA formation occurred in the pH range of 7 to 8. The application of prechlorination may increase or reduce the NDMA conversion, depending on the chlorine reactivity towards the amine group and its surrounding structures. Water matrix components can slow down the initial NDMA formation from selected pharmaceuticals most likely due to the formation of natural organic matter (NOM)-pharmaceutical complexes, while they had less impact on the ultimate NDMA molar conversion. The application of prechlorination may enhance the initial reaction by destroying the NOM-pharmaceutical complexes, but prolonged prechlorination may further inhibit the NDMA formation due to the binding between pharmaceuticals and NOM breakdown products.

The formation of disinfection by-products (DBPs) in drinking water has become an issue of greater concern in recent years. Bench-scale jar tests were conducted on a surface water to evaluate the impact of enhanced coagulation on the removal of organic DBP precursors and the formation of trihalomethanes (THMs) and haloacetic acids (HAAs). The results of this testing indicate that enhanced coagulation practices can improve treated water quality without increasing coagulant dosage. The data generated were also used to develop artificial neural networks (ANNs) to predict THM and HAA formation. Testing of these models showed high correlations between the actual and predicted data. In addition, an experimental plan was developed to use ANNs for treatment optimization at the Peterborough pilot plant.

Quantification of natural organic matter (NOM) in water is limited by the complex and varied nature of compounds found in natural waters. Current characterization techniques, which identify and quantify fractions of NOM, are often expensive and time consuming suggesting the need for rapid and accurate characterization methods. In this work, principal component analysis of fluorescence excitation-emission matrices (FEEM-PCA) was investigated as a NOM characterization technique. Through the use of jar tests and disinfection by-product formation tests, FEEM-PCA was shown to be a good surrogate for disinfection by-product precursors. FEEM-PCA was also applied in order to characterize differences in humic-like, protein-like, and Rayleigh scattering between multiple source waters and due to differing treatment processes. A decrease in Rayleigh scattering influence was observed for a deep lake intake, and multiple processes were found to significantly affect humic-like substances, protein-like, and Rayleigh scattering fractions.

Lignosulfonate (LS), a by-product of the pulp and paper industry, may have the potential to increase fertilizer N availability by acting as a urease and nitrification inhibitor. Four consecutive laboratory studies were conducted to evaluate the behavior of LS in agricultural soils. The effects of various types and rates of LS on soil respiration and soil N dynamics were determined. Effects of LS in combination with fertilizers on microbial activity and N dynamics were measured. Due to the high water solubility of LS a leaching column study was conducted to determine the potential leaching of LS. / Higher rates (20% w/w) of LS initially inhibited microbial activity. Generally LS was relatively resistant to degradation by soil microorganisms and small proportions of added LS-C ($<$2.1%) were leached from the soil columns, but leaching was a function of soil and moisture regime. Recovery of added mineral LS-N from soil treated with LS was low ($<$41%). Mineral N recovered from LS plus fertilizer amended soil was higher than recovery from corresponding fertilizer treatments. Lignosulfonate reduced urea hydrolysis and the proportion of added N volatilized as NH$ sb3$-N from a LS plus urea treatment. The mineral N pool from LS plus fertilizer treated soils had significantly lower NO$ sb3$-N concentrations than corresponding fertilizer treatments. Nitrification inhibition was believed to have been due to high fertilizer concentrations. At reduced urea and LS concentrations, LS decreased NO$ sb3$-N recovery in one of four soil types. However, reduced recovery may not have been from nitrification inhibition but possibly from denitrification or chemical reactions between N and phenolics from LS.

Biochemical properties, functional properties, and market potential of Pacific whiting (PW) fish sauce were investigated. Biochemical properties of fish sauce made from whole fish (W) and a mixture (1:1) of whole fish and surimi byproducts (WB) were compared. Market potential was evaluated through phone interviews and consumer panelists. Proteolysis was primarily affected by cathepsin B-like and L-like enzymes. Acidic pH (4-5) with low salt concentration (15-20%) provided a greater degree of hydrolysis (DH), total nitrogen, and amino nitrogen content in PW fish sauce compared to the traditional process. The greatest Angiotensin Converting Enzyme (ACE) inhibition (96.8%) was found in samples fermented with 15% salt at pH 5.0 for 30 days. Anti-oxidative activity (AT) increased when fermentation continued and depended on fermentation pH. Peptides with MW <590 Da possibly played an important role in ACE inhibition. Consumer tests disclosed no significant difference in flavor liking and overall liking among fish sauce samples (W, WB, and commercial anchovy fish sauce). / Graduation date: 2004

No description available.

Thesis (MSc)--Stellenbosch University, 2003. / ENGLISH ABSTRACT: Please refer to full text for abstract / AFRIKAANSE OPSOMMING: Sien asb volteks vir opsomming

Thesis (MSc Food Sc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: South Africa is a developing country that relies on its agricultural sector as a main source of overall economic welfare. Development does not only give rise to new technology and new products but also results in increased amounts of liquid and solid waste. Generally, the production of wine is considered an environmentally friendly process, but significant amounts of natural resources and organic amendments are necessary, while generating large amounts of liquid and solid wastes. Anaerobic digestion (AD) is an attractive and proven treatment option for both liquid and solid wastes as valuable products and depollution can be obtained. AD of liquid waste results in an effluent and biogas, while anaerobic composting of solid waste results in an organic amendment, leachate and biogas. The overall objective of this study was to investigate the operational feasibility of the cotreatment of leachate produced during the anaerobic composting (AnC) of grape skins in an upflow anaerobic sludge blanket (UASB) reactor while treating winery wastewater. This first aim of this study was to investigate the efficiency of the anaerobic composting of grape skins. Laboratoryscaled digesters (1L) were utilised as anaerobic composting units. The most important operational parameters were identified (pH, moisture content and inoculum (size, ratio, composition)) in order to produce a pH stable, odour free compost in 21 days. Experimental studies highlighted the importance of shredding waste as well as the addition of calcium oxide and green waste to increase the initial pH of the composting mixture. After optimising a 50% (m.m-1) cow manure inoculum, lower inoculum concentrations (10, 15 and 25% (m.m-1)) were investigated to make the process more economically viable. A 10% (m.m-1) anaerobic compost (AC) inoculum was found to produce the most favourable results in terms of pH stabilisation and leachate generation. A 50% (m.m-1) moisture level performed the best by attaining a pH > 6.5 on day 6 and having the highest end pH (7.65) on day 21, while white and red grape skins in an equal ratio were found to generate a higher end pH. With all these optimum parameters in place (shredded waste, green waste, CaO, inoculum, moisture, grape skins), a compost with a final pH (7.09), moisture (58%), nitrogen (2.25%), phosphorous (0.22%) and potassium content (1.7%) was obtained. The optimised parameters were scaled-up (1:10) by using polyvinyl chloride anaerobic digesters (20 L) to suit the operational requirements of the AnC process and also produced a stable compost within 21 days. The second aim of this study was to investigate the combined anaerobic digestion of winery wastewater (WWW) and leachate obtained from the anaerobic composting of grape skins in an upflow anaerobic sludge blanket (UASB). This involved the operation of a 2.3 L laboratory-scale UASB reactor for 205 days. The reactor successfully co-treated WWW and leachate at ca. 8.5 kgCOD.m-3d-1 with a final chemical oxygen demand (COD) reduction of over 90%, a stable reactor effluent pH (7.61) and alkalinity (3 281 CaCO3 mg.L-1). This study showed the feasibility for the combined treatment of liquid and solid waste from the winemaking process. Although the legal limits for reactor effluent disposal onto land was not met, significant reduction in COD concentrations were achieved, whilst producing a soil amendment that could potentially result in cost savings for chemical fertilisers. The benefits related to using anaerobic bioconversion as a treatment option for liquid and solid waste could possibly be advantageous to the wine industry as an environmental control technology, by converting liquid and solid waste into valuable resources. / AFRIKAANSE OPSOMMING: Suid-Afrika is 'n ontwikkelende land wat staatmaak op sy landbousektor as 'n hoofbron van algehele ekonomiese welstand. Ontwikkeling gee nie net aanleiding tot nuwe tegnologie en nuwe produkte nie, maar lei ook tot die verhoogde bydrae van vloeistof sowel as vaste afval. Oor die algemeen, word die produksie van wyn beskou as 'n omgewingsvriendelike proses, maar aansienlike hoeveelhede natuurlike hulpbronne en organiese kunsbemesting word benodig, terwyl groot hoeveelhede vloeistof en vaste afval gegenereer word. Anaërobiese vertering (AV) is 'n aantreklike en bewese behandelingsopsie vir beide vloeistof en vaste afval aangesien waardevolle produkte en suiwering verkry kan word. AV van vloeistowwe lewer uitvloeisel sowel as biogas, terwyl anaërobiese kompostering van vaste afval 'n organiese kunsbemesting, loog en biogas lewer. Die oorhoofse doel van hierdie studie was om die operasionele doeltreffendheid van die mede-behandeling van loog wat gegenereer word tydens die anaërobiese kompostering (AnK) van druiwe doppe in 'n opvloei-anaërobiese-slykkombers (OAS) reaktor terwyl kelderafvalwater behandel word, te ondersoek. Die eerste mikpunt van hierdie studie was om die doeltreffendheid van die anaërobiese komposteringsproses van druiwe doppe te ondersoek. Laboratorium-skaal verteerders (1L) is gebruik as anaërobiese komposteringseenhede. Die belangrikste operasionele parameters is geïdentifiseer (pH, voginhoud en inokulum (grootte, verhouding, samestelling)) om ‘n 'n pH-stabiele, reukvrye kompos te produseer in 21 dae. Die belangrikheid van gesnipperde afval asook die byvoeging van kalsiumoksied en groen afval om die aanvanklike pH van die komposmengsel te verhoog, is deur eksperimentele studies beklemtoom. Na die optimering van 'n 50% (m.m-1) koeimis inokulum, is laer inokulum konsentrasies (10, 15 en 25% (m.m-1)) geondersoek om die proses meer ekonomies uitvoerbaar te maak. Daar is gevind dat ‘n 10% (m.m-1) anaërobiese kompos (AK) inokulum die mees gunstige resultate lewer in terme van pH stabilisering en loog generering. ‘n 50% (m.m-1) vloeistof vlak het die beste presteer deur 'n pH> 6.5 te bereik teen Dag 6 asook die hoogste eind pH (7.65) teen Dag 21, terwyl wit en rooi druiwe doppe in dieselfde verhouding gevind is om ‘n hoër eind pH te genereer. Met al hierdie optimum parameters in plek (gesnipperde afval, groen afval, kalsiumoksied, inokulum, vog, druiwe doppe) is 'n kompos met 'n finale pH (7.09), vog (58%), stikstof (2.25%), fosfor (0.22%) en kalium inhoud (1.7%) verkry. Die optimale parameters is opgeskaal (1:10) deur gebruik te maak van polivinielchloried anaërobiese verteerders (20 L) om aan die operasionele vereistes van die AnK proses te voldoen en ook om 'n stabiele kompos binne 21 dae te produseer. Die tweede mikpunt van hierdie studie was om die gekombineerde anaërobiese vertering van kelderafvalwater en loog, verkry vanaf die anaërobiese kompos van druiwe doppe in 'n OAS reaktor, te ondersoek. Dit het die bedryf van 'n 2.3 L laboratorium-skaal OAS reaktor vir 205 dae ingesluit. Die reaktor het kelderafwater en loog suksesvol behandel by ongeveer 8.5 kgCSV.m-3d-1 met 'n finale chemiese suurstof vereiste (CSV) vermindering van meer as 90%, 'n stabiele reaktor uitvloeisel pH (7.61) en alkaliniteit (3 281 CaCO3mg.L-1). Hierdie studie het die uitvoerbaarheid van die gekombineerde behandeling van vloeistof en vaste afval van die wynmaakproses getoon. Alhoewel die wetlike vereistes van die reaktor uitvloeisel vir storting op grond nie bereik is nie, is ‘n beduidende vermindering in CSV konsentrasies bereik, asook die vervaardiging van kunsbemesting wat die potensiële aankoopkoste van chemiese kunsmis kan verminder. Die voordele verbonde aan die gebruik van anaërobiese bio-omskakeling as 'n behandelingsopsie vir vloeistof en vaste afval kan moontlik voordelig wees vir die wynbedryf as 'n omgewingsbeheerende tegnologie deur om vloeistof en vaste afval om te skakel na waardevolle bronne.