High feed costs and increasing demand for fishmeal have intensified the search for alternative protein sources which are needed to allow world aquaculture to continue expanding. A severely underused marine resource is processing wastes of various types of seafood, which are often disposed of at great cost. Therefore, this study was conducted to evaluate three different types of seafood processing wastes as potential feed ingredients for the red drum (Sciaenops ocellatus). The three processing wastes evaluated were heads and shells from Penaeid shrimp, and viscera and skeletal remains from filleted black drum (Pogonias cromis) and channel catfish (Ictaluras punctatus). These wastes were blended with soybean meal in a 40:60 ratio, dry extruded and dried to produce stable ingredients. All three byproduct meals produced had crude protein levels ranging from 45 to 50 percent. Two feeding trials were conducted to evaluate the different processing waste byproduct meals in comparison to menhaden fishmeal. A digestibility trial was conducted with sub-adult red drum which led to the computation of apparent digestibility coefficients (ADCs) for organic matter, protein, lipid and energy for each of the byproduct meals. Each byproduct meal had relatively high ADC values that were generally similar to those of menhaden fishmeal. A comparative growth trial with red drum was then conducted in which experimental diets were formulated with the three byproduct meals replacing menhaden fishmeal on an equal-digestible-protein basis at levels of 65 percent, 80 percent, or 95 percent. Juvenile red drum were fed the various diets for 8 weeks in a brackish (6 plus/minus 1 ppt) water recirculating system after which weight gain, survival, feed efficiency, as well as whole-body proximate composition and condition indices were measured. All three of the byproduct meals could replace up to 65 percent of the protein provided by fishmeal without adversely affecting performance of red drum. However, the shrimp byproduct consistently provided the highest performance values at 80 percent replacement. The catfish byproduct yielded the lowest fish performance at all levels. This study indicates that dry extrusion of seafood processing wastes can be used to replace a considerable amount of fishmeal in feeds for red drum.

Chromium has been widely used in many industrial applications. As a result of chromite ore processing, large amounts of chromite ore processing waste (COPW) material that can be classified as hazardous have been produced and released into the environment. Therefore, knowledge of migration behavior and leaching rates of chromium through waste materials and soils are of primary concern for environmentally sound management of land-disposal hazardous wastes. Hask&ouml / k (1998) experimentally studied leaching rates of total Cr and Cr(VI) using laboratory columns packed with chromium COPW material produced by a sodium chromite plant. Based on the experimental results of Hask&ouml / k (1998), present study aim, through mathematical modeling, to understand the dissolution kinetics of chromium during leaching of COPW material and to investigate the effectiveness of intermittent leaching involving a sequence of batch (dissolution) and leaching (mass flushing) operational modes. Obtained results show that a coupled system of two first order differential equations was able to capture the essential characteristics of leaching behavior of COPW material. In addition, the kinetics of chromium dissolution from COPW appeared to be controlled by the difference between aqueous phase concentration and a saturation concentration, by the mass fraction of dissolvable chromium remaining in the solid phase, and finally by the contribution of a constant dissolution rate manifested as a steady-state tailing behavior. As a result of performed simulations it was seen that intermittent leaching could be 65%and 35% more effective than continuous leaching for total Cr and Cr(VI), respectively.

No description available.

Dairy processing waste (DPW) can cause many environmental problems if not treated well. Various wastewater treatment technologies have been applied to reduce the organics and inorganics in DPW. The overall objective of this research was to develop cost effective anaerobic digestion technology for hydrogen and methane production from DPW. This search included three phases of studies. In phase 1, we investigated continuous fermentations of algae, lawn grass clippings and DPW, commingled and digested in duplicate 60 L and 3,800 L Induced Bed Reactor (IBR) anaerobic digesters at mesophilic conditions in trials that went for about two years. The goal was to commingle municipal waste in such a way that no pH control chemicals would be required. The research also yielded information about solids loading rate (SLR), efficiency of chemical oxygen demand (COD) and solids removal and biogas production. Under the conditions of the study, commingling algae or grass with DPW made it possible to avoid the addition of pH control chemicals. In phase 2, we investigated the effects of pH, temperature, and hydraulic retention time (HRT) and organic loading rate (OLR) on hydrogen production from DPW in semicontinuous 60 L pilot IBR. Results show pH played a key role on hydrogen production and the optimal pH range was 4.8-5.5. Digestion under thermophilic temperatures (60 °C) had advantages of gaining higher hydrogen yield and suppressing the growth of methanogens. The optimal OLR was 32.9 g-COD/l-d at HRT of 3 days. Under optimal conditions, highest hydrogen yield was 160.7 ml/g-COD removed with 44.6% COD removal. In phase 3, a mathematic model was built and implemented in R based on Anaerobic Digestion Model No. 1 (ADM1) for predicting and describing the anaerobic hydrogen production process. The modified ADM1 was then validated by comparing the predictions with observations of anaerobic hydrogen production from dairy processing waste. The model successfully predicted hydrogen production, hydrogen content, methane content, VFA concentration, and digestion system stability. This study provides a useful mathematical model to investigate anaerobic hydrogen production process and stability.

Made available in DSpace on 2016-08-29T15:37:23Z (GMT). No. of bitstreams: 1 tese_5659_MATEUS LAENDER PACHECO.pdf: 4020965 bytes, checksum: 3b97a49fee7e2100d4b5d6a0a7df5eb3 (MD5) Previous issue date: 2012-03-26 / Objetivou-se com este trabalho avaliar as características físico-químicas e nutricionais da silagem ácida de resíduos da filetagem de tilápia e o desempenho de juvenis de tilápia do Nilo (Oreochromis niloticus) arraçoados com dietas constituídas dessa silagem. Para tanto foram realizados três experimentos, sendo o primeiro para avaliar a variação do pH e a composição bromatológica de silagens formuladas com resíduos da filetagem de tilápia com: 5% de ácido acético, 3% de ácido acético + 2% de ácido fosfórico e 5% de ácido fosfórico. O preparo da silagem consistiu na moagem do resíduo, acidificação, homogeneização e monitoramento do pH durante 30 dias. Foram efetuadas análises para a determinação da umidade, proteína bruta, extrato etéreo e matéria mineral das silagens nos dias 0, 10, 20 e 30 de armazenamento. Os valores de pH ao final do tempo de armazenamento para as silagens de ácido acético, acético + fosfórico e fosfórico foram de 4,37; 4,11 e 3,42 respectivamente. Observou-se efeito (P<0,05) para os diferentes tipos de ácidos utilizados na confecção das silagens quanto para os diferentes períodos de armazenamento, sobre os parâmetros analisados, com exceção da umidade da silagem de ácido acético. A silagem ácida de resíduos da filetagem de tilápia acidificada com 5% de ácido acético apresentou composição bromatológica superior às demais silagens, podendo ser utilizada na alimentação animal assim que ocorre a estabilização do pH aos 21 dias de armazenamento. No segundo experimento, objetivou-se determinar os valores dos coeficientes de digestibilidade aparente da matéria seca, proteína bruta e energia bruta da silagem ácida de resíduos da filetagem de tilápia pela tilápia do Nilo (Oreochromis niloticus) em duas faixas de peso (25 g e 130 g de peso vivo), alimentadas com dietas constituídas de níveis crescentes desse alimento. Foram utilizados 720 juvenis, masculinizados, sendo 360 com peso médio de 25 g (ensaio 1) e 360 com peso médio de 130g (ensaio 2), acondicionados em cubas cilíndricas de fundo cônico com capacidade de 60 L e de 200 L de água, respectivamente. Para a determinação dos coeficientes de digestibilidade aparente, foi utilizada uma ração referência a qual foi misturada ao ingrediente teste (pré-seco) nas proporções de 95:05, 90:10, 85:15, 80:20 e 70:30, constituindo as rações teste. Os coeficientes de digestibilidade aparente (%) da matéria seca, proteína bruta e energia bruta obtidos no ensaio 1 foram respectivamente de 93,57; 97,05 e 94,50 para 5% de inclusão, 93,15; 96,74 e 95,08 para 10% de inclusão, 92,54; 96,86 e 95,60 para 15% de inclusão, 91,92; 95,88 e 94,96 para 20% de inclusão, 91,47; 95,39 e 94,80 para 30% de inclusão, enquanto que os valores no ensaio 2 foram 84,62; 90,35 e 82,21 para 5% de inclusão, 82,85; 90,33 e 83,41 para 10% de inclusão, 83,18; 90,61 e 84,56 para 15% de inclusão, 84,12; 86,44 e 85,61 para 20% de inclusão e 87,54; 91,20 e 88,65 para 30% de inclusão. A silagem ácida de resíduos da filetagem de tilápia é alimento proteico com bons coeficientes de digestibilidade. Em ensaios de digestibilidade, recomenda-se nível de inclusão de 5% para juvenis com 25 g e nível de 30% para juvenis com 130g. No terceiro experimento objetivou-se avaliar o desempenho e a composição de carcaça de juvenis de tilápia do Nilo (Oreochromis niloticus) alimentados com rações contendo diferentes níveis de silagem ácida de resíduos da filetagem de tilápia. Foram utilizadas cinco rações experimentais com 0% (tratamento 1), 5% (tratamento 2), 10% (tratamento 3), 15% (tratamento 4) e 20% (tratamento 5) de silagem. As variáveis de desempenho analisadas foram: peso final, consumo de ração, conversão alimentar aparente, ganho de peso, taxa de sobrevivência, eficiência proteica para ganho, taxa de crescimento específico e eficiência de retenção de nitrogênio. As variáveis de composição de carcaça foram: deposição de gordura e proteína corporal e teores de umidade, proteína, matéria mineral e gordura da carcaça. Foram distribuídos 1.200 juvenis em delineamento experimental inteiramente ao acaso, em cinco tratamentos e oito repetições e 30 peixes por unidade experimental. Os peixes foram alojados em aquários de polietileno com capacidade para 300 L de água. Com exceção da taxa de sobrevivência e da deposição de gordura corporal, as demais variáveis analisadas apresentaram efeito (P<0,05). A silagem ácida de resíduos de filetagem de tilápia pré-seca pode ser incluída em até 5,83% (21,59% na matéria natural) em dietas para juvenis de tilápia do Nilo, para máximo ganho de peso. / The objective of this study was to evaluate the phy sico-chemical and nutritional characteristics of the waste acid silage of tilapia and performance of juvenile Nile tilapia (Oreochromis niloticus) fed diets consisting of silage. For both experiments were carried out, being the first to evaluate the change in pH and chemical composition of silages made with residues of tilapia with: 5% acetic acid, 3% acetic acid + 2% phosphoric acid and 5% phosphoric acid. The preparation of the silage was the grinding of the residual acidification, homogenising and monitoring pH during 30 days. Analyzes were performed to determine the moisture, crude protein, ether extract and mineral matter of the silages at days 0 , 10, 20 and 30 of storage. The pH at the end of storage time for silage acetic acid, phosphoric acetic and phosphoric + were 4.37, 4.11 and 3.42 respectively. Effect was observed (P<0.05) for the different types of acids used in making silage and for different periods of storage on the parameters analyzed, except for moisture silage acetic acid. The acid silage from tilapia filleting residue acidified with 5% acetic acid showed the chemical composition superior to other treatments may be used in animal feed so to stabilization of pH at 21 days of storage. In the second experiment aimed to determine the coefficients of apparent digestibility of dry matter, crude protein and gross energy of the acid silage of tilapia residues for Nile tilapia (Oreochromis niloticus) in two weight ranges (25 g and 130 g body weight), fed diets with increasing levels of food. 720 juveniles were used, male domination, and 360 with an average weight of 25 g (experiment 1) and 360 with an average weight of 130 g (test 2), packe d in cylindrical tanks with conical bottom capacity of 60 L and 200 L of water , respectively. For the determination of apparent digestibility coefficients, was used a reference diet, which was mixed with the ingredient test (pre-dried) in the proportions 95:05, 90:10, 85:15, 80:20 and 70:30, making the test rations. The apparent digestibility coefficients (%) of dry matter, crude protein and gross energy obtained in trial 1 were respectively 93.57, 97.05 and 94.50 for 5% inclusion, 93.15, 96.74 and 95.08 to 10% inclusion, 92.54, 96.86 and 95.60 to 15% inclusion, 91.92, 95.88 and 94.96 to 20% inclusion, 91.47, 95.39 and 94.80 to 30% of addition, while the values in Test 2 were 84.62, 90.35 and 82.21 to 5% inclusion, 82.85, 90.33 and 83.41 to 10% of inclusion , 83.18, 90.61 and 84.56 to 15% inclusion, 84.12, 86.44 and 85.61 to 2 0% of inclusion and 87.54, 91.20 and 88.65 to 30% inclusion. The waste acid silage of tilapia is food with good protein digestibility. Assays digestibility, it is recommended dietary level of 5% to juvenile 25 g 30% level for juvenile with 130 g. In the third experiment aimed to evaluate the performance and carcass composition of juvenile Nil e tilapia (Oreochromis niloticus) fed diets containing different levels of acid silage of tilapia waste. Five experimental diets were used containing 0% (treatment 1), 5% (treatment 2), 10% (treatment 3), 15% (treatment 4) and 20% (treatment 5) of silage. The performance variables analyzed were: final weight, feed intake, feed conversion, weight gain, survival rate, protein efficiency for gain, specific growth rate and efficiency of nitrogen retention. The carcass composition variables were: deposition of body fat and protein and moisture, protein, ash and fat from the carcass. 1200 juveniles were distributed in completely randomized experimental design in five treatments and eight replicates and 30 fish per experimental unit. Fish were housed in polyethylene tanks with a capacity of 300 L of water. With the exception of survival rate and body fat deposition, the remaining variables had an effect (P<0.05). The acid silage of tilapia filleting residue pre-drought can be included up to 5.83% (21.59% in fresh matter) in diets for juvenile Nile tilapia, for maximum weight gain

>Magister Scientiae - MSc / Nature through billions of years of trial and error has produced an immeasurable amount of natural systems like plants, birds and animals. The intelligence of nature is hidden in these natural systems and researchers are turning towards “Nature’s intelligence” to find inspiration and advance novelty in the development of nanomaterials. Gold nanoparticles (AuNPs) have unique optical, electronic and physicochemical features which has gained them popularity and widespread exploitation in various applications. The conventional methods used for AuNPs synthesis employs toxic chemicals which makes these NPs unsafe for biomedical applications. Hence, there is a search for new, ‘green’ and more cost effective methods for AuNPs synthesis. Plant extracts are regarded as a highly desirable system for nanoparticle synthesis due to their tremendous capability to produce a wide range of phytochemicals that can act as reducing agents. The main goal of this study was to synthesize AuNPs in a cost effective manner without the use of toxic chemicals in the synthesis process. Avocado seeds which are an agricultural waste by-product were used for the biosynthesis of AuNPs. The study reports on the synthesis optimization, characterization and activities of the biogenic AuNPs. The avocado seed extract mediated - AuNPs (AvoSE-AuNPs) were optimized by varying reaction parameters and characterized by UV-visible, Dynamic Light Scattering (DLS) and High Resolution Transmission Electron Microscopy (HRTEM), Zetasizer and Fourier Transform Infrared Spectroscopy (FTIR). The formation of AvoSE-AuNPs had an absorption maximum at 534 nm. HRTEM and DLS confirmed that the NPs were polydispersed and present in different shapes. The presence of phytochemical constituents on the AvoSE-AuNPs were confirmed by FTIR. Their potential antibacterial activity was tested on bacterial strains known to exhibit resistance to a number of current antibiotics. The catalytic activity of AvoSE-AuNPs was also assessed as a means to contribute to the development of new methods aimed at alleviating organic pollutants such as nitrophenols in the environment. The AvoSE-AuNPs demonstrated excellent catalytic activity in the reduction of 4-NP by NaBH4 as shown by the rapid decrease in the nitrophenolate absorption band at 400 nm and the appearance of new absorption band at 298 nm, revealing the formation of the 4-aminophenol. Furthermore, the rate constants calculated demonstrated that the reaction occurs faster in the presence AvoSEAuNPs. The AvoSE-AuNPs showed low significant cytotoxicity. Cell cycle analysis was conducted to further investigate the apparent exhibited toxicity of the AvoSE-AuNPs. The results showed that in both cell lines treated with AvoSE-AuNPs and AvoSE there was a ii | P a g e disruption in the regulation of cell cycle. Cell cycle analysis helped improve understanding of the low cytotoxicity observed by the MTT assay results. The results presented in this study clearly demonstrate the feasibility of using AvoSE for the synthesis of AuNPs. This study demonstrated that AvoSE mediated AuNPs synthesis is a greener alternative as it abides by the green chemistry principles. Furthermore, the study outcomes contributed to minimizing environmental pollution by finding use for agricultural waste and thus ultimately adding value to the field.

Thesis (MBA (Business Management))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: The objective of the study was to establish whether a small-scale biomass renewable energy project that uses waste fruit and pomace as the predominant feedstock could be a feasible clean development mechanism (CDM) project. The study was based on the solid waste streams of a pome fruit processor. Renewable energy technologies that convert biomass into a methane rich gas were evaluated. These included the various anaerobic digestion technologies that yield biogas and gasification technologies that yield syngas. Gasification was not found to be a feasible technology due to the moisture content requirement of less than 20% against that of the biomass of 70-80% and due to the low bulk density of the biomass of 250 kg/m3 versus the required minimum of 500kg/m3. The biogas could either be fired in a combined heat and power (CHP) unit or in a dual fired burner with heavy furnace oil (HFO). Feeding the thermal energy and electricity from the CHP unit back to the processor or supplying the electricity to the national electricity grid was considered. The plant would supply electricity to the national electricity grid as an Independent Power Producer (IPP). Eskom would be the renewable energy purchasing agent (REPA) that purchases the electricity at an anticipated R0.96/kWh under a power purchase agreement (PPA) in terms of the renewable energy feed-in tariff phase II (REFIT) guidelines. The anticipated revenue for electricity was six fold the coal offset cost of R0.16/kWh, while there was no demand for the heat energy after the processing season, thus firing biogas in a dual fired burner was not feasible. The most feasible technology was the anaerobic digestion of the biomass using a continuous stirred tank reactor (CSTR) process followed by a CHP unit that feeds the heat to the processing facility and the electricity into the national electricity grid. Waste fruit and wet pomace would be codigested with abattoir waste during the operating season. Dried pomace, abattoir waste, waste fruit and any other non-woody material from the surrounding farms and packhouses would be digested after the season to optimize the utilisation of the plant capacity. A capacity of 11 dry tons per day for the case study at a cost of R13 138 889 yielded an IRR of 15.2% and a net present value (NPV) of - R1 498 616 based on a discount rate of 18%, when excluding revenue from the sale of carbon emission reductions (CERs). Therefore, without the sale of CERs, this project would be rejected as a non-feasible investment. The project is eligible for CDM registration as a small-scale renewable energy project activity. No barriers were identified that would prevent the registration of this project activity as a CDM project in South Africa. The sale of CERs increased the NPV of the optimum solution to R156 483 and the IRR to 18.3%. Registering the project as a CDM project activity improved the feasibility of the project to the extent that it was marginally feasible. The fermentation and hydrolysis of the biomass into bioethanol was investigated as an alternative to the generation of heat and electricity. Although the technology is proven, no facilities were identified that use spoilt apples or apple pomace as the substrate. This increased the risk of the project and a discount rate of 24% was set when calculating the project NPV. This project activity yielded an NPV of - R1 296 057 when excluding CDM revenue. The feasibility improved to an NPV of - R263 507 and an IRR of 23.4% when taking the additional revenue from the sale of CERs into account. This project alternative was only marginally out of the money. With the development of newer technology, this alternative could prove to be more attractive in the future.

Thesis (PhD) -- tellenbosch University, 2014. / ENGLISH ABSTRACT: This study is part of the continuing global research effort dedicated to finding alternative aquafeed ingredients, which not only replace fish meal and fish oil as sources of essential nutrients in aquafeeds, but also provide specialist functional properties when included in feeds. Due to constraints in supply of fish meal and fish oil originating from wild capture fisheries, the continually growing aquafeed industry requires new sources of raw materials for the production of high quality feeds. The aim of the study was to investigate the specialist functional properties of feed ingredients (with emphasis on immune-stimulation potential) derived from fish processing waste after enzymatic hydrolysis by endogenous proteolytic enzymes (autolysis). Further aims were to (i) quantify effects of these feed ingredients on production performance of two species relevant to the South African aquaculture industry, namely Mozambique tilapia Oreochromis mossambicus and South African abalone Haliotis midae, (ii) compare performance to commercially available enzymatically produced feed ingredients, and (iii) separate the functional effects of these fish processing waste derived feed ingredients from the acid used to preserve them against bacterial spoilage during the autolysis process. Oil recovered after autolysis of rainbow trout viscera proved to be an attractive feed ingredient due to favourable effects on the non-specific cellular immune function of both Mozambique tilapia and South African abalone. However, in South African abalone, increased immune function due to inclusion of fish oil was accompanied by a significant decrease in production performance. The inclusion of hydrolysed proteins, obtained by autolysis of fish waste, in aquaculture feeds also improved non-specific immunity and survival of Mozambique tilapia significantly – independently of the preserving acid – although the same was not observed for South African abalone. Production performance was dependent on dietary hydrolysed protein inclusion levels in both species; excessive inclusion resulted in decreased production performance. The performance of dietary hydrolysed protein from autolysis and those from commercial production processes were significantly different, possibly as a result of different raw material origins and production processes. It is further shown that formic acid can contribute to improved water stability in abalone feeds, a novel mode of action not previously described. The study concludes that the simple autolysis process for processing of fish waste can provide aquafeed ingredients with immune stimulatory potential, which can contribute to improved production performance in the Mozambique tilapia and the South African abalone. The result can contribute to improved sustainability of the aquafeed industry, through substitution of fish meal and fish oil derived from capture fisheries with processed fish waste components. / AFRIKAANSE OPSOMMING: Hierdie studie vorm deel van die voortdurende en wêreldwye soeke na nuwe akwakultuur voerbestanddele wat nie net vismeel en –olie kan vervang as bron van noodsaaklike voedingstowwe nie, maar wat ook gespesialiseerde funksionele eienskappe openbaar wanneer dit in akwavoere ingesluit word. As gevolg van beperkings in die voorsiening van vismeel en –olie afkomstig vanaf wilde visserye, word die voortdurend groeiende akwavoer bedryf genoodsaak om nuwe grondstowwe te benut vir die vervaardiging van hoë kwaliteit voere. Die doelwit van die studie was om moontlike gespesialiseerde funksionele eienskappe (met spesifieke klem op potensiële immuun-stimulasie) van voerbestanddele te ondersoek wat herwin is vanaf reënboogforel proseseringsafval, na ensiematiese hidrolise d.m.v. endogene ensieme teenwoordig in die afval (outolise). Verdere doelwitte was om (i) effekte op produksie prestasie van hierdie bestanddele te kwantifiseer in twee akwakultuur spesies relevant tot die Suid- Afrikaanse bedryf (naamlik die Mosambiekse kurper Oreochromis mossambicus en die Suid- Afrikaanse perlemoen Haliotis midae), (ii) om produksie prestasie te vergelyk met kommersieel beskikbare voerbestanddele voorberei d.m.v. ensiemtegnologie, en (iii) om die moontlike effekte van die voerbestanddele te skei van die van die sure gebruik om die bestanddele te preserveer tydens die outolitiese proses. Daar is bevind dat olie herwin na outolise van reënboogforel ingewande ‘n goeie voerbestanddeel is wat gunstige effekte op die nie-spesifieke, sellulêre immuniteit van beide Mosambiekse kurper en Suid-Afrikaanse perlemoen gehad het. In die Suid-Afrikaanse perlemoen het verbeterde immuunfunksie gepaard gegaan met ‘n verswakking in produksie prestasie. Die gehidroliseerde proteïen komponent van ge-outoliseerde prosesseringsafval het ook beduidende verbetering in nie spesifieke immuniteit en oorlewing van Mosambiekse kurper tot gevolg gehad - onafhanklik van die preserverende suur - maar dieselfde is nie in die Suid-Afrikaanse perlemoen waargeneem nie. Produksie prestasie was afhanklik van die insluitingsvlakke van gehidroliseerde proteïen in beide spesies en dit is bevind dat oormatige insluiting produksie nadelig beïnvloed. Prestasie van proteïen afkomstig van outolise en die van ‘n kommersiële produksieproses het beduidend verskil, moontlik as gevolg van verskillende grondstowwe en prosesseringstegnieke. Daar is verder vir die eerste keer getoon dat mieresuur ‘n beduidende verbetering in waterstabiliteit in sekere perlemoenvoere teweeg kan bring. Die studie kom tot die slotsom dat die eenvoudige outolise proses funksionele akwavoerbestanddele kan produseer wat kan bydra tot ‘n verbetering in produksie prestasie in die Mosambiekse kurper en Suid-Afrikaanse perlemoen. Die resultaat kan bydra tot verbeterde volhoubaarheid van die akwavoer bedryf, deur vismeel en –olie afkomstig van wilde visserye, te vervang.

South Africa is facing numerous challenges that pertain to increasing water deficit and pollution of water resources. Only 40 out of 821 wastewater treatment works in South Africa achieved Green Drop certifications in the 2010 Green Drop assessments (DWA, 2011). This is not only threatening net water availability but also human health. South African water sources are comprised of 77 % surface water, 14 % return flows and 9 % groundwater (van Vuuren, 2009). This study was therefore intended to explore the quality, quantity and treatability of corn wet milling effluent resulting from Tongaat Hulett Starch Pty Ltd (THS) operations. THS is a major producer of corn derived starch and glucose in Africa. Amongst its three corn wet milling plants in Gauteng (Kliprivier, Germiston and Meyerton) and one in Western Cape (Bellville), 600000 tonnes of maize were processed in the 2011/2012 financial year. The objective of the study was to establish the wastewater footprint of the corn wet milling process. To achieve this, qualitative and quantitative characterisation studies were completed on effluents generated from the Germiston and Meyerton corn wet milling plants, respectively. This characterisation study was focused on volumetric and organic load analyses of the various sections of the corn wet milling process. A full scale anaerobic digestion treatability study of the Meyerton plant effluent was also conducted. The study results indicated that the combined effluent discharged to the Municipal sewer averaged between 2.9 and 3.1 m3/tonne of corn processed. The effluent generated resulted in an average chemical oxygen demand (COD) concentrations of between 6211 and 7790 mg/L, with suspended solid concentrations of between 635 and 899 mg/L. From the full scale anaerobic treatability study, a minimum of 87 % COD removal at organic volumetric loading rates (OLR) of between 0.3 and 3.9 kg COD/m3.d was achieved. It was concluded that corn wet milling effluent can be categorised as high strength in terms of COD concentrations. This type of effluent proved to be amenable to anaerobic digestion treatment. Anaerobic pretreatment of corn wet milling effluent can proportionately reduce pollution loading into the receiving municipal conventional wastewater treatment systems. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2013.

Thesis (M. S.)--Mechanical Engineering, Georgia Institute of Technology, 2008. / Committee Chair: Willem F.G. Van Rooijen; Committee Member: Ghiaasiaan, Seyed M; Committee Member: Weston M. Stacey