Ethanol production wastewater is known to be toxic, and is not easily biodegradable. It also consists of a variety of coloured components adding to the complex composition of this wastewater. Disposal of this wastewater into water courses is not recommended and yet is performed all over the world. Investigation of this wastewater found that there was a high concentration of sulphate which, in the presence of sulphate-reducing prokaryotes can cause sulphide corrosion of cement. The concentration of sulphate in the wastewater was approximately 2770 mg/L. It was also found that the wastewater pH was very low and discharge of the wastewater into the wastewater treatment works caused a negative impact on the overall quality of the final wastewater discharged to sea. It was found using FISH techniques that there were no sulphate-reducing prokaryotes present in the wastewaters but that a sulphate-reducing population existed on the sewer wall. An anaerobic contact process was designed to treat this wastewater targeting sulphate reduction to sulphide, to be converted into elemental sulphur and to increase the wastewater pH. The process did not achieve this aim and only approximately 20-30 % reduction in sulphate from the wastewater was achieved with little to no change in the pH. A 95 % reduction in sulphate concentration was needed in order to reach acceptable discharge limits. Sulphate reduction could not be carried out, even under ideal laboratory conditions. It was found that the barrier causing the digester failure was the high concentration of phenols present in the wastewater (3.3 g/L) together with the production of high concentrations of volatile fatty acids (on average 13 g acetic/L). These two components are known to cause digester failure, especially phenols, and phenols are usually only degraded by fungal species. It was concluded that the wastewater itself was not amenable to this method of biological treatment.

Emerging Technologies Sustainability Assessment (ETSA) is a new technology assessment tool that was developed in order to compare emerging processes or technologies to existing alternatives. It utilizes infoIDlation modules, with the minimum use of resources such as time and money, in order to deteIDline if the process under development is comparatively favourable and should be developed beyond the early conceptual phase. The preliminary ETSA is vital in order to identify the gaps in the existing information and the specific methodologies to be used for data capture and analysis. The use of experimental design tools, such as Design-Expert, can facilitate rapid and efficient collection of necessary data and fits in well with the rationale for the ETSA. Wine distillery effluent (vinasse) is the residue left after alcohol has been distilled from fennented grape juice. It is an acidic, darkly coloured effluent, with a high COD and polyphenol content. The most popular method of disposal of this effluent, land application, is no longer viable due to stricter legislation and pressure on the industry to better manage its wastes. Although the ability of whiterot fungi to degrade a number of pollutants is well-known, fungal treatment of wine distillery effluent is still in the conceptual phase. The perfoIDlance of the fungal remediation system was assessed experimentally in terms of COD removal and laccase production using Design-Expert. Although Pycnoporus sanguine us was found to be most efficient at COD removal (85%) from 30% vinasse, laccase production was low (0.021 U/I). The optimum design for economically viable fungal treatment used Trametespubescens. This fungus was able to remove over 50% of the COD from undiluted vinasse while producing almost 800U/l of the valuable laccase enzyme within three days. Since the effluent from the fungal system did not meet the legal limits for wastewater disposal, a two-stage aerobicanaerobic system is suggested to improve the quality of the effluent prior to disposal. The ETSA was used to assess the fungal technology in relation to the two current methods of vinasse treatment and disposal, namely land application and anaerobic digestion. Based on the ETSA, which considered environmental, social and economic impacts, the fungal system proved to be potentially competitive and further development of the technology is suggested.

Thesis (MScEng (Process Engineering))--University of Stellenbosch, 2005. / The thesis reports the investigation of various distillery processes and wastewater streams. The aim was to evaluate the processes and thereafter design interventions for improved wastewater treatment at the respective distilleries. An integrated environmental approach was adopted based on the principle that prevention of pollution is the preferred option and end-of-pipe treatment the least favoured option. As such, feed material to the processes was studied to determine whether some of the components that are not required in the distillation process could in fact be removed prior to entering the system. The results indicate that organic constituents such as phenol and tartaric acid could be removed using physico-chemical and biological treatment methods. The treatment of effluent was studied using an Upflow Anaerobic Sludge Blanket (UASB) set-up to determine the reduction in Chemical Oxygen Demand (COD) in the wastewater. Thereafter the UASB treated effluent was exposed to aeration for further treatment. Summary of conclusions • Pretreatment of wine feed material with calcium hydroxide is effective in removal of 98% tartaric acid, 30% COD and a total phenol content of 57%. • Bio-augmentation results showed that the soil inoculum was the most effective treatment method with reductions of 61% COD at a temperature of 30°C, tartaric acid removal of 98% at the same temperature and 25% reduction in total phenol at 26°C. • UASB was effective with soil inoculum and removed approximately 90% of COD although operational problems were experienced and hindered the operation of the plant. • Aeration of UASB effluent further reduced the COD by a further 60% with a total COD reduction of 96% after both UASB and aeration treatment. • Effective reduction of total phosphorus by 70% and the total phenol content by 80% was achieved by UASB treatment followed by aeration.

Dissertation (PhD)--University of Stellenbosch, 2006. / ENGLISH ABSTRACT: Constructed wetlands have been widely used in the treatment of industrial and domestic wastewater to reduce biological and chemical oxygen demand (BOD and COD), to remove nitrate and enteric viruses as well as to generally improve water quality. Distillery wastewater has a complex character due to high concentrations of sugars, lignins, hemicellulose, dextrins, resins, polyphenols and organic acids, leading to a high COD that may exceed 100 000 mg/L. The potential application for the treatment of distillery wastewater by means of constructed wetlands is relatively unexplored. In 1999 a study was initiated at Distell Goudini distillery, Western Cape, South Africa, to explore the possibility of using constructed wetlands to treat distillery wastewater. It was found that constructed wetlands do have the ability to treat distillery wastewater providing that the influent COD does not exceed 15 000 mg/L for extended periods and the correct substrate material is used. The present study expanded on the above-mentioned study and specifically aimed to provide information on the microbiological controls in wetland systems in an applied sense that may contribute to improved treatment efficiency. Furthermore, this project aimed to contribute to our fundamental understanding of the microbial ecology of constructed wetlands used for the treatment of distillery wastewater. This study revealed that a highly dynamic microbial composition exists within wetlands. Furthermore it was found that wetlands can efficiently remove COD even though a low degree of similarity exists between microbial communities in various zones of the same wetland and those between different wetlands, as well as low similarity between communities sampled from the same zone over time. This demonstrates that it will be difficult to define the ‘ideal’ degradative community in terms of microbiological criteria and serves as a reminder that various indicators should be considered for monitoring system health. Furthermore the shifts in microbial community composition illustrate the ability of microbial communities to adapt to changes in the environment without compromising their functional efficacy. When studying the attached microbial communities within wetland systems it was found that different morphotypes are detected at certain stages of biofilm development while some organisms are present at most phases of biofilm formation. Measurement of CO2 production and dissolved organic carbon (DOC) removal in laboratory scale columns showed that grazing protists had a notable effect on overall microbial activity and that organic loading influenced these predator-prey interactions. Interestingly, increased clogging of pores occurred in the presence of protists, resulting in reduced flow through the porous matrix. Terminalrestriction fragment length polymorphism (T-RFLP) analysis of biofilms on gravel in experimental wetlands indicated that the presence of protists and algae had an effect on the microbial community composition. Scanning electron microscopy (SEM) showed that the presence of algae also had an influence on biofilm structure suggesting that the algae provided labile nutrients that were utilized by the bacterial and yeast members of the community. Finally, augmentation with a commercial mixture or microbial populations isolated from distillery effluent demonstrated that the concentration at which supplements are applied influence degradative efficiency. / AFRIKAANSE OPSOMMING: Kunsmatige vleilande word wêreldwyd gebruik in die behandeling van indusriële en huishoudelike afvalwater om biologiese en chemiese suurstof aanvraag (BSA en CSA) te verminder, om nitrate en ingewandsvirusse te verwyder asook om waterkwaliteit in die algemeen te verbeter. Distilleerafvalwater het komplekse eienskappe as gevolg van hoë konsentrasies suiker, lignien, hemisellulose, dekstrien, harpuis, polifenole en organiese sure, wat lei tot ‘n hoë CSA wat 100 000 mg/L kan oorskry. Daar is tot op hede relatief min studies gedoen oor die potensiële gebruik van kunsmatige vleilande vir die behandeling van distilleerafvalwater. In 1999 is ‘n studie by Distell Goudini distilleeraanleg in die Wes Kaap van Suid Afrika onderneem om die moontlikheid van kunsmatige vleilande vir die behandeling van distilleerafvalwater te bestudeer. Daar was bevind dat kunsmatige vleilande die vermoë het om distilleerafvalwater te behandel gegewe dat die invloeiende CSA nie 15 000 mg/L oorskry nie en dat die regte substraat materiaal gebruik word. Die huidige studie het by die bogenoemde studie aangesluit met die doel om informasie oor die mikrobiologiese kontroles in vleilandsisteme op ‘n toegepaste wyse te voorsien, wat tot verbeterde behandeling doeltreffendheid kan lei. Hierdie studie het verder beoog om by te dra tot ons fundementele kennis van die mikrobiese ekologie van kunsmatige vleilande wat gebruik word vir die behandeling van distilleerafvalwater. Dié studie het bevind dat daar ‘n hoogs dinamiese mikrobiese samestelling binne vleilande bestaan. Daar was verder bevind dat CSA steeds effektief deur vleilande verwyder kan word alhoewel daar ‘n lae graad van ooreenstemming is tussen mikrobiese gemeenskappe in verskeie sones van dieselfde vleiland en verskillende vleilande, asook ‘n lae graad van ooreenstemming tussen gemeenskappe wat in dieselfde sone oor tyd gemonster is. Dit demonstreer dat dit moeilik sal wees om die ‘ideale’ degraderende gemeenskap te vind in terme van mikrobiologiese kriteria en dien as ‘n herinnering dat verkeie indikatore in ag geneem moet word om die welstand van ‘n ekologiese sisteem te monitor. Die verskuiwings in mikrobiese gemeenskapsamestelling illustreer verder die vermoë van natuurlike sisteme om aan te pas by veranderinge in die omgewing sonder om funksionele doeltreffendheid te verminder. Die studie van aangehegte mikobiese gemeenskappe het aangedui dat veskillende morfotipes bespeur kan word tydens sekere fases van biofilm formasie terwyl sekere organismes tydens meeste van die fases teenwoordig is. Die bepaling van CO2 produksie en die verwydering van opgeloste organiese koolstof in laboratoriumskaal kolomme het geïlustreer dat voedende protiste ‘n waarneembare effek gehad op die algehele mikrobiese aktiwiteit en dat die organiese lading hierdie predator-prooi interaksie beïnvloed het. Dit was interessant om te vind dat die teenwoordigheid van protiste die verstopping van porieë aangehelp het en dus tot verlaagde vloei deur die poreuse matriks gelei het. Terminale-restriksie fragment lengte polimorfisme (T-RFLP) analiese van biolfilm op klipgruis in eksperimentele vleilande het aangedui dat die teenwoordigheid van protiste en alge ‘n effek gehad het op die mikrobiese gemeenskapsamestelling. Skandeerelektronmikroskopie (SEM) het bewys dat die teenwoordigheid van alge ook ‘n invloed op biofilm struktuur gehad het wat daarop dui dat alge maklik afbreekbare voedingstowwe aan die bakterieë en giste van die mikrobiese gemeenskap beskikbaar gestel het. Laastens was bewys dat die konsentrasie van toevoeging van ‘n kommersiële mikrobiese mengsel of mikrobiese populasies wat uit afvoer geïsoleer was, die effektiwiteit van degradering kan beïnvloed.

Thesis (MSc Food Sc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: The large volumes of effluent water generated by distillery industries is an issue of great concern as it contains pollutants that must be treated according to environmental legislation. It has been reported that grain distillery wastewater (GDWW) is high in fats, oils and greases (FOG) that can be reduced by treating with suitable microorganisms. The objective of this study was to investigate the biodegradability of FOG in GDWW. This was done by isolating lipolytic bacteria from soil, which was situated close to the GDWW treatment plant at a distillery in Wellington, South Africa. These isolates were screened for lipolytic activity on various fat substrates. Secondly, the most desirable isolates were subjected to batch biodegradation trials using GDWW as substrate and tested for their ability to biodegrade FOG. Each of the four isolates, Pseudomonas fluorescens (1), Pseudomonas luteola (2), Stenotrophomonas maltophilia (3) and Bacillus licheniformis (4) were screened on three types of media: DifcoTM Spirit Blue Agar with Tributyrin (SBA-Tri); Victoria Blue B Agar with Cotton Seed Oil (VBB-CSO); and Victoria Blue B Agar with GDWW (VBB-GDWW) at different temperatures (25°C, 30°C, 37°C and 50°C) to determine optimal enzyme activity for lipolysis. Lipolysis was taken as positive when growth of dark blue colonies was formed or by the formation of a clear zone around the colony. Lipolysis was observed at all the aforementioned temperatures for P. fluorescens, P. luteola and S. maltophilia. Bacillus licheniformis failed to show any lipolytic activity at 50°C on the SBA-Tri. A decrease in lipolytic (clear) zone was observed at an increase in temperature from 25°C to 37°C for P. fluorescens. When VBB-GDWW was used as lipid substrate, isolates failed to indicate any clear zone of lipolysis, however, growth was present for all isolates in the form of a dark blue zone around colonies, which were also positive for lipolytic activity. Three lipolytic bacteria (P. luteola, S. maltophilia, and B. licheniformis) isolated from the above study were subjected to GDWW of various FOG concentrations (70 – 211 mg.L-1). These isolates were allowed to acclimatise to GDWW during a batch biodegradation period (18 – 21 d) at 37°C. Bacillus licheniformis showed the highest FOG reduction of 83% after 18 d exposure. All the strains showed that an initial acclimatisation phase improved the biodegradation of the FOG. A fatty acid profile was obtained for each batch biodegradation trial after the acclimatisation phase. It was found that these strains either biodegraded the fatty acids (FAs) or, as in the case of P. luteola, formed myristic and pentadecyclic acids from free FAs. The formation of FAs may have occurred through a process of inter-esterification. It was also found that certain precursors such as palmitoleic acid might be formed under aerobic or anaerobic conditions. In this study it was shown that biodegradation of FOG can be improved by an initial acclimatisation period. Single cultures with the desirable properties can be used to lower the FOG in GDWW and need not be used in mixed cultures that could produce inhibitory components that would otherwise upset the biodegradation activity of isolates present. Bacillus licheniformis could be used as a FOG-degrading isolate during the treatment of wastewaters high in FOG. However, future studies should focus on bioaugmenting the FOG degrading bacteria from this study with other strains to monitor its activity and ensure survival and activity in larger scale studies. / AFRIKAANSE OPSOMMING: Die groot volumes afloopwater wat opgelewer word deur die distilleer-industrie is ‘n kwessie wat groot kommer wek aangesien dit groot hoeveelhede besoedelende stowwe bevat. Daarom moet dit, volgens omgewingsverwante wetgewing, behandel word. Daar is voorheen gerapporteer dat graandistillerings-afloopwater (GDAW) hoog is in vette, olies en ghries (VOG) en dat hierdie VOG verminder kan word deur die GDAW te behandel met toepaslike mikroörganismes. Die oorhoofse doelstelling van hierdie studie was om die bioafbreekbaarheid van die VOG in GDAW te ondersoek. Dit is eerstens gedoen deur lipolitiese bakterieë uit grond wat naby ‘n graandistillerings-aanleg (Wellington, SuidAfrika) geleë is, te isoleer. Verskeie vetsubstrate is gebruik om hierdie isolate vir lipolitiese aktiwiteit te toets. Tweedens is die verkose isolate getoets vir lipolitiese aktiwiteit deur gebruik te maak van lot-bio-afbreekbaarheidsmetode. Tydens hierdie metode is GDAW as substraat gebruik en die verskillende bakterieë se vermoë om VOG af te breek is getoets. Om die optimale ensiemaktiwiteit vir lipolise van elk van die vier isolate nl. Pseudomonas fluorescens (1), Pseudomonas luteola (2), Stenotrophomonas maltophilia (3) en Bacillus licheniformis (4), vas te stel, is elk getoets op drie verkillende media: “DifcoTM Spirit Blue Agar” met Tributirien (SBA-Tri); “Victoria Blue B Agar” met Katoensaadolie (VBB-KSO); en “Victoria Blue B Agar” met GDAW (VBB-GDAW) teen verskillende temperature (25°C, 30°C, 37°C en 50°C). Indien donker-blou kolonies gevorm is of ‘n deursigbare sone rondom ‘n kolonie waargeneem is, is lipolise as “positief” beskou. Lipolise is waargeneem teen alle voorafgenoemde temperature vir P. fluorescens, P. luteola en S. maltophilia. Bacillus licheniformis het nie lipolitiese aktiwiteit getoon teen 50°C op SBA-Tri. ‘n Afname in die deursigbare sone is waargeneem teenoor ‘n toename in temperatuur vanaf 25°C tot 37°C vir P. fluorescens. In die geval van VBB-GDAW as lipiedsubstraat, het isolate geen deursigbare sone vir lipolise getoon nie. Daar was egter ‘n donker-blou sone rondom kolonies teenwoordig, wat ook positief is vir lipolitiese aktiwiteit. Drie lipolitiese bakterieë (P. luteola, S. maltophilia, and B. licheniformis) is geïsoleer uit bogenoemde studie en is aan inkubasie in GDAW teen verksillende VOGkonsentrasies (70 – 211 mg.L-1) blootgestel. Hierdie isolate is toegelaat om te akklimatiseer tot die GDAW tydens ‘n lot-bio-afbreekbaarheidstydperk (18 – 21 d) teen 37°C. Bacillus licheniformis het die hoogste VOG-afname van 83% na 18 d blootstelling getoon. Alle bakterieë het getoon dat ‘n aanvanklike akklimatiserings-tydperk die bioafbreekbaarheid van die VOG verbeter. ‘n Vetsuur-profiel is verkry vir elk van die lot-bio afbreekbaarheidstoetse na die akklimatiserings-fase. Daar is bevind dat hierdie bakterieë óf die vetsure afgebreek het óf, soos in die geval van P. luteola, miristiese en pentadesikliese sure, vanaf vry-vetsure, gevorm het. Die vorming van vetsure is moontlik as gevolg van die proses van inter-esterifikasie. Dit is verder bevind dat sekere voorlopers, soos palmitoë-oleïensuur, gevorm kan word onder aërobies of anaërobiese toestande. In hierdie studie is getoon dan die bio-afbreekbaarheid van VOG verbeter kan word deur ‘n aanvanklike akklimatiserings-tydperk toe te pas. Enkel-kulture met die verkose eienskappe kan gebruik word om die VOG in GDAW te verminder. Gemengde kulture, wat inhiberende komponente produseer wat moontlik die bio-afbreekbaarheids proses negatief kan beïnvloed, hoef dus nie gebruik te word nie. Bacillus licheniformis kan gebruik word as ‘n VOG-afbrekende isolaat tydens die behandeling van afloopwater wat hoog in VOG is. Verdere studies moet egter fokus op die samevoeging van VOGafbrekende bakterieë vanuit hierdie studie asook ander bakterieë om die aktiwiteit daarvan te monitor en sodoende oorlewing en aktiwteit op ‘n groter skaal te verseker.

In this study white-rot fungi were investigated for their efficiency at distillery wastewater remediation and the production of laccase as a valuable by-product. Distillery wastewaters are high in organic load and low in pH. The presence of phenolic compounds can lead to extremely colour-rich wastewaters and can be toxic to microorganisms. The presence of the inorganic ions may also affect biological treatment. White-rot fungi are unique among eukaryotic or prokaryotic microbes in possessing powerful oxidative enzyme systems that can degrade lignin to carbon dioxide. These ligninolytic enzymes, such as lignin peroxidase, manganese peroxidase and laccase, are capable of degrading a vast range of toxic, recalcitrant environmental pollutants and this makes the white-rot fungi strong candidates for the bioremediation of polluted soils and waters. The laccase enzyme alone has shown remediation potential in wastewaters such as beer production effluent, olive mill wastewater, alcohol distillery wastes, dye-containing wastewaters from the textile industry as well as wastewaters from the paper and pulp industry. It has been shown to be capable of remediating soils and waters polluted with chlorinated phenolic compounds, polyaromatic hydrocarbons, nitrosubstituted compounds and fungicides, herbicides and insecticides.

Thesis (MScFoodSc)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Large volumes of high strength wastewater are generated annually by distilleries. Treatment of this wastewater is essential to increase its reuse potential. Anaerobic digestion (AD) has been widely applied as high strength wastewater treatment. Additionally, grain distillery wastewater (GDWW) is high in fats, oils and grease (FOG) which can cause problems during AD. Pre-treatment is therefore often required to make the AD process more efficient. The overall objective of this study was to investigate the operational efficiency of upflow anaerobic sludge blanket (UASB) reactors while treating GDWW as substrate. The first aim was to investigate the pre-treatment of the GDWW specifically for the removal of FOG by evaluating the effect of pH adaption, coagulant concentration and ozone (O3) dosages on the FOG reduction efficiency. Secondly, the effect of two different pre-treatments (only coagulant and coagulant and ozone) on the subsequent UASB treatment step was investigated. The pH of raw GDWW (pH 3.4) was adapted to three different pH values (5.0, 6.0, and 7.0) and the coagulant, aluminium chlorohydrate (ACH) (140 mg.L-1), was added. To make the process more economically viable, the lowering the coagulant concentration (to 100 mgACH.L-1) was also investigated. Optimal reductions for chemical oxygen demand (COD) (33.2% ± 4.93), total suspended solids (TSS) (91.9% ± 1.73) and FOG (84.1% ± 1.98) were, however, achieved at a higher coagulant concentration of 140 mgACH.L-1, and at a wastewater pH of 7.0. The effect of additional ozone treatment was also investigated. Maximum reductions for the ozone treatment were obtained at 100 mgO3.L-1 for COD (3.6% ± 4.08), and at 900 mgO3.L-1 for TSS (27.7% ± 5.58) and FOG (23.9% ± 1.83). The ozone treatment was most efficient for FOG reduction (in terms of mg FOG reduced per mg ozone) at 100 mgO3.L-1. An ozone dosage of 300 mgO3.L-1, was decided on based on economic feasibility, findings in literature on toxicity of ozone and the potential degradation of recalcitrant compounds at this dosage. The final pre-treatment thus included pH adaption to 7.0, coagulant dosage of 140 mgACH.L-1, and an ozone dosage of 300 mgO3.L-1. The second part of this study involved the operation of two 2 L laboratory scale UASB reactors for 277 days. The substrate of the first reactor contained GDWW that had only undergone coagulant pre-treatment (Rcontrol), while the substrate of the second UASB reactor consisted of GDWW that had undergone coagulant and ozone pre-treatment (Rozone). Both reactors treated the pre-treated GDWW successfully at ca. 9 kgCOD.m-3d-1. COD reductions of 96% for Rcontrol and 93% for Rozone, were achieved. FOG reductions (%) showed variations throughout the study and maximum reductions of 88% and 92% were achieved for Rcontrol and Rozone, respectively. The Rozone produced more biogas, but the methane content was similar for both reactors. The additional ozone pre-treatment did not show any added benefits to the reactor performance results. UASB granule washout in Rcontrol did, however, suggest possible toxicity of unsaturated fatty acids present in the non-ozonated substrate. The feasibility of FOG removal was shown as both reactors successfully treated pre-treated GDWW. Ozonation, after a coagulant dosage, which resulted in further reduction in the FOG content of the GDWW, is thus not essential to ensure the success of an anaerobic digestion step. Ozonation of the pre-treated GDWW could, however, be beneficial to gas production and the efficiency of a tertiary biological process. / AFRIKAANSE OPSOMMING: Groot volumes hoë-sterkte afloopwater word jaarliks deur distilleerderye opgelewer. Die behandeling van hierdie afloopwater is noodsaaklik om die hergebruiksmoontlikheid daarvan te verhoog. Die toepassing van anaërobiese vertering (AV) is wydverspreid in hoë-sterkte afloopwaterbehandeling. Graandistillerings-afloopwater (GDAW) is boonop hoog in vette, olies en ghries (VOG), wat probleme kan veroorsaak tydens AV. Voorbehandeling word dus dikwels verlang om die AV meer doeltreffend te maak. Die oorhoofse doelstelling van hierdie studie was om die doeltreffendheid van opvloei-anaërobieseslykkombers- (OAS-) reaktore wat GDAW as substraat behandel, te ondersoek. Die eerste mikpunt was om die voorbehandeling van die GDAW, te ondersoek vir die verwydering van VOG. Dit is uitgevoer deur die uitwerking van pH aanpassing, koagulantkonsentrasie en osoon(O3)dosis op VOG vermindering te evalueer. Tweedens is die uitwerking van twee verskillende voorbehandelings (slegs koagulant asook koagulant en osoonbehandeling) op die opvolgende OAS-behandelingsstap ondersoek. Die pH van rou GDAW (pH 3.4) is aangepas tot drie verskillende pH waardes (5.0, 6.0 en 7.0) en die koagulant, aluminium-chlorohidraat (ACH), is bygevoeg (140 mg.L-1). Om die proses meer ekonomies uitvoerbaar te maak is ‘n verlaagde koagulantkonsentrasie (verlaag tot 100 mgACH.L-1) ook ondersoek. Die optimale afnames vir chemiese suurstofvereiste (CSV) (33.2% ± 4.93), totale oplosbare vastestowwe (TOV) (91.9% ± 1.73) en VOG (84.1% ± 1.98) is egter bereik teen ‘n hoër koagulant konsentrasie van 140 mgACH.L-1, en teen ‘n afloopwater-pH van 7.0. Die uitwerking van ‘n bykomende osoonbehandeling is ook ondersoek. Die hoogste afnames tydens die osoonbehandeling is bereik teen 100 mgO3.L-1 vir CSV (3.6% ± 4.08), en teen 900 mgO3.L-1 vir TOV (27.7% ± 5.58) en VOG (23.9% ± 1.83). Die osoonbehandeling was mees doeltreffend vir VOG (in terme van mg VOG verwyder per mg osoon) teen 100 mgO3.L-1. Daar is besluit op ‘n van 300 mgO3.L-1, as gevolg van die ekonomiese uitvoerbaarheid, bevindinge in literatuur vir die toksisiteit van osoon, en die moontlike afbraak van moeilik-afbreekbare komponente teen hierdie dosis. Die finale voorbehandeling het dus bestaan uit ‘n aanpassing van die afloopwater-pH na 7.0, ‘n koagulantdosis van 140 mgACH.L-1, en ‘n osoondosis van 300 mgO3.L-1. Tydens die tweede gedeelte van hierdie studie is twee 2 L laboratoriumskaal OAS reaktore bedryf vir 277 dae. Die substraat van die eerste reaktor het GDAW bevat wat slegs ‘n koagulant-voorbehandeling ondergaan het (Rkontrole), terwyl die substraat van die tweede OAS-reaktor GDAW bevat het wat koagulant- en osoon-voorbehandeling ondergaan het (Rosoon). Beide reaktore het die voorbehandelde-GDAW suksesvol behandel teen ‘n organieseladingstempo van ca. 9 kgCSV.m-3d-1. Afnames in CSV van 96% vir Rkontrole en 93% vir Rosoon, is bereik. Tydens die studie is deurlopende wisseling in VOG verwydering (%) waargeneem, en die hoogste verwyderings wat bereik is, is onderskeidelik 88% en 92% vir Rkontrole en Rosoon. Die Rosoon het meer biogas geproduseer, maar die metaanpersentasie was soortgelyk vir beide reaktore. Die osoon-voorbehandeling het nie enige toegevoegde voordele getoon in die reaktorprestasie resultate nie. Die uitwas van die OAS-granules vir die Rkontrole het egter moontlike toksisiteit van onversadigdevetsure aangedui, wat moontlik teenwoordig kon wees in die nie-geösoneerde substraat. Die uitvoerbaarheid van VOG verwydering is getoon aangesien beide reaktore voorbehandelde GDAW suksesvol behandel het. Osonering, wat verdere afname in die VOG inhoud van GDAW teweeggebring het (na ‘n koagulant dosis), is dus nie noodsaaklik vir die suksesvolle verloop van ‘n anaërobiese-verteringsstap nie. Osonering van die voorbehandelde GDAW kan egter voordelig wees vir gasvorming, en kan ook verder die doeltreffendheid van ‘n tersiêre biologiese behandeling verhoog.

Thesis (MScFoodSc)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Waste generated by the distillery industry is a major ecological concern and disposal thereof without a suitable treatment can have damaging effects on the environment. The characteristics of this type of wastewater are highly variable and dependent on the raw material used and production process followed. Grain distillery wastewater (GDWW) is also rich in fats, oils and grease (FOG). Successful treatments of distillery wastewater and GDWW have been reported using an upflow anaerobic sludge blanket (UASB) reactor technology. The aim of this study was to investigate the ability of lab-scale UASB reactor to treat FOG-reduced GDWW and the subsequent enhancement thereof following an unique feeding strategy approach. Firstly, a coagulation/flocculation-centrifugation step was developed to obtain FOG-reduced GDWW. Secondly, the efficiency of a lab-scale UASB reactor was investigated treating FOG-reduced GDWW at pre-determined operational parameters as well as the verification of biomass acclimatisation. Lastly, the effect of a unique feeding strategy of FOG-reduced GDWW to lab-scale UASB reactor granules was investigated in terms of COD, FOG-reduction and biomass acclimatisation. It was found that a coagulation/flocculation-centrifugation treatment removed sufficient amounts of FOG and TSS from GDWW. Different commercially available coagulation/flocculation products were evaluated whilst used in combination with a centrifugation step for improved sedimentation and separation. The FOG removal remained between 90 and 97% for the ferric chloride (FeCl3) and Ferrifloc 1820 treatments, respectively, whereas the TSS removal ranged between 56 and 93%, respectively. The use of a high molecular weight polymer (Ultrafloc 5000) and an aluminium chlorohydrate (Ultrafloc 3800) proved to be less effective in terms of FOG removal efficiency, ranging from 72 to 86%. It was decided to pre-treat GDWW with FeCl3 in combination with centrifugation to obtain FOG-reduced GDWW for subsequent UASB reactor treatment investigations. The FOG-reduced GDWW was fed into a laboratory-scale UASB reactor (2 L) over a period of 331 days. During the operational period different feeding parameters were attained to establish the ability of the UASB reactor to efficiently treat FOG-reduced GDWW. The COD removal increased from 60 to 85% at an organic loading rate (OLR) of ca. 5.5 kgCOD.m-3.d-1 (pH = 7.5) whilst FOG removal remained between 45 and 70%. COD removal increased to 90% with the attainment of an OLR of ca.10 kgCOD.m-3.d-1 (pH = 7.5) whereas FOG removal remained in the region of 55 and 65%. COD and FOG removal remained above 85% and 50%, respectively, when substrate pH was decreased to 6.50 (OLR ca. 10 kgCOD.m-3.d-1). A granule activity test was performed on seed and FOG-reduced GDWW fed granules to determine biomass acclimatisation. FOG-reduced GDWW fed granules showed higher activity in terms of methane production rate and cumulative methane production suggesting biomass acclimatisation. The FOG-reduced GDWW was fed to a laboratory-scale UASB reactor following a unique feeding approach. The feeding approach consisted of several feeding and starvation cycles. Improved average biogas production was observed during the feeding (0.26 to 11.3 L.d-1) and starvation (1.8 to 4.2 L.d-1) cycles as higher loading rates were obtained during each feeding cycle. After the completion of the strategic feeding the UASB reactor was continuously fed at an organic loading rate of ca. 5 kgCOD.m-3.d-1. The COD reduction efficiency improved from 70 to 80%, however, FOG removal remained in the region of 60%. Granule activity tests done on days 0, 215 and 279 showed improved UASB granule activity to FOG-reduced GDWW with operation time in terms of methane production rate and cumulative methane production. This study has proven that a coagulation/flocculation-centrifugation treatment of GDWW can remove sufficient amounts of FOG and TSS before the commencement of a UASB treatment, however, such a technique would require more refinement. It was also found that a UASB reactor can successfully treat FOG-reduced GDWW, however, it must be advised that close monitoring of the UASB reactor is required in order to maintain efficient COD reduction. A strategic feeding approach proved to be successful, but further improvement of the UASB efficiency to treat FOG-reduced GDWW in terms of stable COD and FOG reduction, stable effluent pH, improved biogas production and biomass activity must still be explored. / AFRIKAANSE OPSOMMING: Afloop water wat gegenereer word deur die distillerings-industrie veroorsaak ‘n ekologiese kommer en wegdoening daarvan sonder geskikte behandeling, kan ernstige gevolge op die omgewing hê. Die eienskappe van hierdie tipe afvalwater kan varieer en is afhanklik van die rou materiale gebruik en die produksie proses wat gevolg is. Graan distillery afloop water (GDAW) deel dieselfde eienskappe met die van distillery afloop water, alhoewel dit ook hoog is in vette, olies en ghries (VOG). Suksesvolle behandeling van distillery afloop water en GDAW met n opvloei-anaërobiese slykkombers (OAS) reaktor is deur verskeie navorsers gerapporteer. Die doel van hierdie studie was om die uitvoerbaarheid van laboratorium skaal OAS reaktor, wat VOG-verminderde GDAW behandel te ondersoek, asook die daaropvolgende verbetering deur n unieke voer strategie te volg. Eerstens, was ‘n koagulasie/flokkulasie-sentrifigasie tegniek ontwikkel om VOG-verminderde GDAW te kry. Tweendens, die effektiwiteit van ‘n lab-skaal OAS reaktor ondersoek, wat gevoer was met VOG-verminderde GDAW, by voorafbepaalde parameters. Laastens, die effek van ‘n unieke voer strategie van VOG-verminderde GDAW op lab-skaal OAS reaktor granules. Dit was vasgestel dat ‘n koagulasie/flokkulasie-sentrifigasie voor behandeling voldoende hoeveelhede VOG en TSS verwyder van GDAW. Verskillende kommersieel beskikbare koagulasie/flokkulasie produkte was in kombinasie met ‘n sentrifugasie stap geëvalueer om sedimentasie en skeiding te verbeter. Dit was nie ‘n plan om die stap te perfek nie, maar dat dit eerder sou dien as ‘n voorbehandeling stap vir opeenvolgende ondersoeke. Die VOG verwydering het tussen 90 en 97% gevariëer vir ferri chloride (FeCl3) en Ferrifloc 1820 (Chlorchem) en TSS verwydering het tussen 56 en 93% gewissel. Die gebruik van ‘n hoë molekulêre gewig polimeer (Ultrafloc 5000) en ‘n aluminium chlorohidraat (Ultrafloc 3800) was minder effektief met n VOG verwydering wat tussen 72 en 86% gewissel het. Die VOG-verminderde GDAW was in ‘n laboratorium-skaal OAS reaktor oor ‘n tydperk van 331 dae behandel. Verskillende voer doelwitte was geëvaluaeer om te bepaal of ‘n OAS reaktor GDAW suksesvol kan behandel. CSB afbraak het van 60 to 85% gestyg teen ‘n organiese lading van 5.5 kgCOD.m-3.d-1 (pH 7.50), met VOG verwydering wat tussen 45 en 70% gewissel het. Die CSB afbraak het na die bereiking van 10 kgCOD.m-3.d-1 (pH 7.50) gestyg na 90% met VOG afbraak tussen 55 en 60% gewissel het. Die CSB en VOG verwydering het bo 85% en 50% onderskeidelik gebly, met die verlaging van substraat pH na 6.50 (CSB ca. 10 kgCOD.m-3.d-1). ‘n Aktiwiteits toets is uitgevoer met saad granules en VOG-verminderde GDAW gevoerde granules. Granules (VOG-verminderde GDAW gevoer) het ‘n hoer aktiwiteit getoon teenoor saad granules in terme van metaan produksie tempo en kumulatiewe metaan produksie. Die VOG-verminderde GDAW was gevoer in ‘n OAS reaktor deur gebruik te maak van ‘n strategiese voertegniek. Die strategie het uit verskeie voer en hongersnood fases bestaan. Verbeterde biogas produksie was tydens voer (0.26 tot 11.3 L.d-1) en hongersnood (1.8 tot 4.2 L.d-1) -fases opgelet soos ‘n hoër lading bereik was. Na die voltooing van die strategiese voer fase was die OAS reaktor op ‘n deurlopende basis teen ‘n lading van 5 kgCOD.m-3.d-1 gevoer. Die CSB verwydering het van 70 na 80% verhoog terwyl VOG afbraak in die omgewing van 60% gewissel het. Biomassa aktiwiteits toetse was uitgevoer is op dag 0, 215 en 279 het verhoogde aktiwiteit vertoon, met ‘n strategiese fase en deurlopende fase teenoor die aanvanklike (ongeaklamatiseerde) granules. Hierdie studie het bewys dat ‘n flokkulasie/koagulasie-sentrifugasie behandeling van GDAW kan dien as ‘n voorbehandelings stap vir opeenvolgende OAS reaktor studies. Dit was gevind dat ‘n OAS reaktor die VOG-verminderde GDAW kan behandel, maar dit word aanbeveel dat die OAS reaktor so sorgvuldig as moontlik gemonitor word om effektiewe CSB verwydering te handhaaf. Ten slotte, ‘n strategiese voer strategie was suksesvol, maar verdere verbetering van die OAS reaktor ten opsigte van die behandeling van VOG-verminderde GDAW moet verder ondersoek word.

Thesis (Msc Food Sc (Food Science))--University of Stellenbosch, 2007. / The distillery industry generates large volumes of heavily polluted wastewater and thus effective wastewater treatment is essential. It has been reported that a chemical oxygen demand (COD) reduction of more than 90% can be achieved when wine distillery wastewater (WDWW) is treated in an upflow anaerobic sludge blanket (UASB) reactor. The first objective of this study was to investigate UASB treatment of WDWW and to try to enhance the efficiency by using ozonation treatments. Secondly, the impact of grain distillery wastewater (GDWW) on UASB granules was determined. The third objective was to determine whether ozonation and enzymatic treatment combinations might improve the biodegradability of GDWW and thus make GDWW more amenable to UASB treatment. It was found that UASB treatment combined with ozonation improved the WDWW treatment efficiency. When diluted WDWW (chemical oxygen demand COD = 4 000 mg.L-1) was ozonated (dose = 47 mg.L-1) in a 50 L venturi circulating contactor system, the COD reduction was 7%. When WDWW was treated in a laboratory-scale UASB reactor (substrate pH = 7.0, COD = 4 000 mg.L-1 and organic loading rate (OLR) = 4.0 kg COD.m-3.d-1), the COD reduction was 92%. When the UASB treatment was combined with either pre- or postozonation, the COD reduction was 94 and 96%, respectively. When UASB treatment was combined with pre- and post-ozonation, a COD reduction of 98% was achieved. The activity of the UASB granules was also found to improve over time, despite the addition of the ozonation treatment. It has been reported that operational problems occur when GDWW is treated in an UASB reactor as a result of the encapsulation of the granules. This was confirmed when granules from a full-scale UASB treating WDWW became encapsulated in a layer after being exposed to GDWW (COD = 4 000 mg.L-1) for 24 d. The results showed that the lipid content of the granules increased from 1.25 to 60.35 mg lipid.g-1 granule over the 24 d exposure period. Therefore, granules exposed to GDWW were encapsulated in a lipid-rich layer and as a result the contact between the GDWW and microbial consortium in the granules was reduced. The operational problems found during the industrial UASB treatment of GDWW were ascribed to the encapsulation of the granules. Combinations of ozonation (dose = 1 476 mg.L-1) generated in a 2 L bubble column and enzymatic treatments (1% FogFreeTM (FF) dosage and 2 d incubation at 35°C) were found to improve the biodegradability of GDWW. This improvement was in terms of lipid reduction in GDWW, granule activity and visual appearance of the encapsulating layer of the granules. The highest lipid reduction (90%), highest granule activity, lowest lipid content of the granules (3.74 ± 0.10 mg.g-1 granule) and best visual appearance were achieved in ozonated GDWW treated with 1% FF, followed by just ozonation. The higher lipid reduction and subsequent higher granule activity were ascribed to the reduction in lipids which resulted in the fact that fewer lipids were available to encapsulate the granules. As a result of the lipid reduction, the granule activity improved and the GDWW was made more amenable to UASB treatment. This study proved that UASB treatment combined with ozonation led to an enhancement of the treatment efficiency of WDWW. It was also found that the cause of the operational problems during UASB treatment of GDWW was as a result of the granules being encapsulated in a lipid-rich layer. It was established that treating GDWW prior to UASB treatment improved the biodegradability of GDWW. The data from the study showed that high lipid reduction in the GDWW directly led to better granule activity, lower granule lipid content and a thinner encapsulating layer. Based on the data from this study, it is recommended that GDWW be ozonated prior to other treatments because it can be done inline and the costs would be lower than that of enzymatic treatments.