Thesis (PhD)--University of Stellenbosch, 2004. / ENGLISH ABSTRACT: The importance of waste management is growing rapidly for several reasons. These reasons include the escalating cost of wastewater treatment and cleaning chemicals, an emerging trend of onerous regulatory regime regarding e uent disposal from governments, rising public awareness on the adverse e ects of industrial waste as well as drastic reduc- tion in water resources in the winegrowing regions. In addition, owing to the large energy demand for refrigeration purposes for high quality wine production and rapidly increasing energy costs, the challenges of energy management in the wine industry were also inves- tigated. In order to address these challenges adequately, the solutions were derived via the integration of two disciplines: environmental science (waste and energy management) and computer science (applications of arti cial intelligence). Therefore, the ndings re- ported from this study seek to advance knowledge through the construction of decision support systems for waste and energy management in circumstances where conventional mathematical formalisms are inadequate. In that sense, the dissertation constitutes in- terdisciplinary research on the application of integrated arti cial intelligence technologies (expert systems and fuzzy logic) in designing and developing decision tools for waste and energy management in the wine industry. The dissertation rst presents the domain of interest, where the scope and breadth of the problems it addresses are clearly de ned. Critical examination of the domain data- bases revealed that data, information, and knowledge for waste and energy management in the wine industry are generally incomplete and lack structure overall. Owing to these characteristics, a hybrid system approach was proposed for the development of decision support systems based on fuzzy logic. The integrated decision support systems were de- veloped based on an object-oriented architecture. This approach facilitated the exible design required for waste and energy management-related complex problem-solving. To illustrate the applicability of the o -line decision tools developed, several case stud- ies mirroring on actual industrial practices were considered. These systems were found to be robust and yielded results that were in accordance with actual industrial practices inthe wine industry. Furthermore, they provided intelligent suggestions in scenarios where there was minimal information, and under certain instances they o ered feasible sugges- tions in circumstances where a human novice could have problems in making the right decisions. / AFRIKAANSE OPSOMMING: Die belangrikheid van afvalbestuur neem om verskeie redes vinnig toe. Die redes sluit in die eskalerende koste van afvalwaterbehandeling en skoonmaakmiddels, streng regula- toriese vereistes van regeringskant met betrekking tot die verwydering van uitvloeisels, toenemende openbare bewustheid van die nadelinge e ekte van nywerheidsafval, sowel as die drastiese afname in waterbronne in wynproduserende omgewings. Daarby, a.g.v. die groot energieverbruik wat deur die verkoeling van hokwaliteitwyn vereis word en die snelgroeiende energiekoste, is die uitdagings van energiebestuur in die wynbedryf ook on- dersoek. Ten einde die uitdagings die hoof te kon bied, is oplossings gevind deur die integrasie van twee disciplines: omgewingswetenskap (afval- en energiebestuur) en rekenaarweten- skap (toepassings van kunsmatige intelligensie). Gevolglik is daar deur die bevindinge van die studie gepoog om kennis te bevorder deur die konstruksie van besluitnemingson- dersteuningstelsels vir afval- en energiebestuur onder omstandighede waar konvensionele wiskundige algoritmes ontoereikend sou wees. In die opsig verteenwoordig die proefskrif interdissiplinre navorsing in die toepassing van gentegreerde kunsmatige intelligensieteg- nologie (kundige stelsels en wasige logika) in die ontwerp en ontwikkeling van besluitne- mingshulpmiddels vir afval- en energiebestuur in die wynindustrie. Die proefskrif baken eers die probleemgebied af, waarna die bestek en omvang van die probleme waarop die werk gemik is duidelik gede nieer word. Kritiese ondersoek van die databasisse in die domein het getoon dat die data, informasie en kennis oor afval- en energiebestuur in die wynbedryf in die algemeen onvolledig en gebrekkig gestruktureer is. A.g.v. di eienskappe, is 'n hibriede stelselbeandering voorgestel vir die ontwikkeling van besluitnemingstelsels gegrond op wasige logika. Die gentegreerde besluitnemingsonders- teuningstelsels is ontwikkel op 'n objek-georinteerde argitektuur. Die benadering het die daarstelling van 'n buigsame ontwerp wat benodig word vir komplekse probleemoplossing in afval- en energiebestuur vergemaklik. Om die toepaslikheid van die a ynige besluitnemingshulpmiddels wat ontwerp is, te illustreer, is verskeie gevallestudies wat werklike industrile praktyk uitbeeld beskou. Diestelsels was robuust en het resultate gelewer wat in ooreenstemming was met werklike industrile praktyke in die wynnywerheid. Die kundige stelsels het verder intelligente voorstelle gemaak in scenarios waar daar minimale informasie beskikbaar was, en onder sekere omstandighede het hulle realistiese oplossings voorgestel waar 'n onkundige persoon probleme sou gehad he tom die regte besluite te kon neem.

Municipal solid waste management (MSWM) is a global challenge and the situation is worse in urban areas of developing countries due to ineffective disposal systems. In many industrialised countries, waste minimisation and recycling/reuse policies have been introduced to reduce the amount of waste generated, and increasingly, alternative waste management practices to waste disposal on land have been implemented to reduce the environmental impacts of MSWM. Nevertheless, research and MSWM in most developing countries have largely concentrated on waste collection. This doctoral study investigates how planning and decision-making for MSW disposal in developing countries with similar circumstances and MSW problems to Ghana can be improved, using the Wa Municipality as a case study. It established the baseline scenario of MSW disposal and examined MSW disposal management and operational performances. The methodology and research design for the study was a descriptive and interpretive case study that was analysed through both qualitative and quantitative research methods. The key research findings indicate that the current state of MSW disposal management performance in Ghana does not present an enabling environment for effective MSW disposal. Also, the present MSW disposal practices in the case study area and Ghana in general consist of some waste collection, transportation and open dumping, where the entire amount of waste is open dumped without pre-treatment. Evaluation of MSW disposal operational performance through modelling and scenario analysis showed that open dumping/landfilling of waste creates copious health effects (0.0001519 lbs/year on average), whereas, MSW disposal in an integrated solid waste management (ISWM) system optimises the minimisation of health effects (-0.0005812 lbs/year on average). The study developed and validated a framework for the improvement of planning and decision-making for MSW disposal, which can easily be applied in the context of developing countries. Also, the developed framework provides a theoretical standpoint for the concept of MSW disposal in ISWM. Appropriate MSW disposal treatment technologies based on the developed framework could be applied to ameliorate the impacts of MSW disposal in Ghana and other developing countries.

The landfilling of Municipal Solid Waste poses a threat to the environment in the form of landfill emissions. These emissions are a result of the biochemical breakdown of the waste in the anaerobic landfill environment. A solution to this problem has been found in the form of the mechanical-biological treatment of waste. This technology involves mechanical and biological processing of the waste before it is placed in the landfill. The pretreatment accelerates the degradation of the waste resulting in the landfilling of a more biologically stable product, resulting in a reduction of the emission potential of the landfill. This research aims at investigating the applicability and efficiency of a passively ventilated MBT windrow system under a sub-tropical climate. The research was conducted in two stages: the first stage focused on the implementation and analysis of the Mechanical Biological Treatment (MBT) process with aerobic windrows, employing the Dome Aeration Technology (OAT) (Mollekopf et al. 2002). Three OAT windrows were constructed at the Bisasar Road Landfill in Durban in order to study the efficiency of the process after different composting timeframes (8 and 20 weeks). The study proved that the use of the OAT technology is a viable option. The second stage was the analysis of this treated waste in an anaerobic environment, in order to simulate landfill conditions and, thus gain insight into the effect of MBP on landfill emissions. Six Iysimeters and 5 columns as well as numerous eluate tests were conducted in order to study the "post-Iandfilled" behaviour of the waste and the effect that waste treatment, composting time and screening have on liquid and gaseous emissions. A basic cost estimate using the Clean Development Mechanism for financial assistance was conducted. The results of this research were then utilised to make recommendations on sustainable waste disposal options. The findings of the research were that although the MBT did not reduce emission levels sufficiently to allow for a 40 year landfill aftercare period, the benefit over the landfilling of untreated waste is significant. / Thesis (Ph.D.)-University of KwaZulu-Natal, Durban, 2009.

South Africa's re-integration into the global economy and the international political arena has brought about an active growth of business locally and internationally. Local companies are expanding into new markets and regions which require them to follow internationally acceptable and approved waste disposal policies in their production of goods and services. To achieve compliance, it is necessary that companies have the appropriate support and backup from waste disposal companies. Also, increasing pressure from environmental groups and government agencies makes it a prerequisite that a company's waste is properly disposed of in the most efficient, lawful and economical way. This research dissertation is aimed at identifying the key factors that impact on the levels of service in the waste industry and an attempt at evaluating the effects of the service levels to determine what actions are necessary to improve the levels of service in the waste industry. As a result, this research was carried out amongst producers of waste in certain areas of KwaZulu-Natal. Various techniques were evaluated in researching how to measure service quality. The most reliable measuring instrument to gauge service quality was found to be the SERVQUAL system. This measuring instrument was evaluated and then modified to suit the particular needs of the waste industry. The SERVQUAL system is a multi-item scale for measuring consumers perceptions of service quality. A sample of 75 companies was selected and senior management was interviewed. Based on the statistical analysis, the discrepancy between service expectations and service delivery in the waste industry is wide. Urgent attention needs to be focused on service delivery, especially reliability, assurance and responsiveness by waste disposal companies. / Thesis (MBA)-University of Natal, Durban, 2003.

ant national legislation on the disposal of waste and waste disposal sites has been promulgated to regulate the dumping of unwanted materials. This development poses major legal compliance problems for the South African National Defence Force (S.A.N.D.F.) deployments in rural areas. The absence of municipal services to these areas and the unavailability of municipal dumpsites do not facilitate adherence to legislation. The development of an integrated waste management system for Defence represents an attempt to ensure compliance with national legislation. An overview and assessment of current waste management practices in the S.A.N.D.F. is provided in this document. The literature review focussed on the theory of waste management, the current situation with regard to sanitation in rural areas and a review of pertinent legislation, and provided the foundation for the development of questionnaires. The study then explored aspects of waste management and sanitation that were taken into consideration in preparing for operations . Data collection entailed interviews with senior members of the S.A.N.D.F. who are responsible for the planning of such projects. Thereafter an investigation was conducted into the waste management practices employed during deployments to rural areas. Data collection in this respect involved the administration of questionnaires to soldiers at temporary bases and during patrols, as well as an audit of the waste generated at the temporary bases, noting how refuse was managed under these conditions. These methods of primary data collection included interviews with various government and non-government officials. Interviews with senior members of the S.A.N.D.F. revealed that the planning and preparation for operations are core-function focused and that the integration of waste management and sanitation in the planning process is minimal and inadequate . The data obtained from questionnaires administered to the soldiers revealed that current waste management practices at the temporary bases and during patrols are considered to be satisfactory to the soldiers, as they are of the opinion that "we are doing the best we can under such circumstances". The waste audit revealed that ninety-eight percent of the waste generated in the study area is recyclable. Consequently, this study recommends that waste management methods be integrated into the planning process. Furthermore it is recommended that environmental education be included as a compulsory module during basic training and re-training for all members of the S.A.N.D.F., i.e. from senior management down to the most junior level. A long-term solution to improve on the current waste management practices is recycling. With regard to sanitation, the Director of Sanitation of the Department of Water Affairs and Forestry (D.W.A.F.) suggested that relevant members of the S.A.N.D.F. meet with members of D.W.A.F. and the Umkhanyakude Regional District Council, to discuss the inclusion of the S.A.N.D.F. in the current sanitation-provision projects in the study area. Short-term solutions were that the S.A.N.D.F. liaise with the G.I.S. section at D.W.A.F. This section will be able to provide the S.A.N.D.F. with information on the location of boreholes and hand-pumps (the only source of drinking water for the local population). The S.A.N.D.F. must ensure that waste disposal sites and field toilets, commonly referred to as go-karts, are located away from these water sources and, whenever possible, on higher ground. / Thesis (M.A.)-University of KwaZulu-Natal,Durban, 2004.

SÖRAB is a waste disposal firm that is operative in nine of the municipalities in Stockholm County, Sweden. Each municipality has their own separate management of information and services. SÖRAB aspires to facilitate the process of finding and placing orders on waste disposal services for the residents in these municipalities. This thesis examines what should be done in order to centralize the municipalities’ waste disposal information into a shared portal. The main difficulties, concerning centralization, are that the municipalities use different underlying customer systems and have different practices in regulating waste disposal rates. After proposals for solutions for the identified problems are presented, an investigation into the most suited application type for the portal is conducted. This investigation focuses on a comparison between the two application types native mobile applications and mobile web applications. The usability of the portal is considered important. Hence different techniques, aiming to increase the usability of the graphical interface, are researched and presented. The identified problem areas, the application study and the usability aspects are the foundation for the development of a functional prototype of the portal. The result of the thesis is a prototype of a responsive web application. The prototype is implemented with the framework Angular. In order to facilitate potential future development, an architectural document describing the prototype is written. The thesis can be usable for future implementation projects. It presents a functioning methodology, gives insight in usability principles and compares pros and cons with different application types. / SÖRAB är ett avfallsbolag som är verksamt i nio av Stockholm läns kommuner. Varje kommun har separat hantering av information och tjänster. SÖRAB vill underlätta för kommuninvånarna att hitta och beställa tillgängliga avfallstjänster. Detta examensarbete undersöker vad som krävs för att centralisera kommunernas avfallsinformation i en gemensam portal. De stora svårigheterna kring centraliseringen ligger i att kommunerna använder olika bakomliggande kundsystem och tillämpar olika sätt att styra sina avfallstaxor. Efter att lösningsförslag för problemområdena presenteras, undersöks vilken typ av plattform som passar bäst för portalen. Denna undersökning jämför de två applikationstyperna nativa mobilapplikationer och mobila webbapplikationer. En viktig del för portalen anses vara dess användarvänlighet. I rapporten undersöks och presenteras därför olika tekniker som kan höja användarvänligheten i grafiska gränsnitt. De identifierade problemområdena, applikationsstudien och användarvänlighetaspekterna, blir underlag för att utveckla en funktionell prototyp av portalen. Examensarbetets resultat är en prototyp av en responsiv webbapplikation. Implementeringen sker med ramverket Angular. För att underlätta eventuellt fortsatt arbete, skrivs ett dokument som beskriver prototypens arkitektur. Rapporten kan vara till nytta för framtida implementeringsprojekt. Den uppvisar en fungerande metodik, ger insikt i användarvänlighetsprinciper och jämför föroch nackdelar med olika applikationstyper.

The provision of clean drinking water typically involves treatment processes to remove contaminants. The conventional process involves coagulation with hydrolysing metal salts, typically of aluminium (‘alum’) or trivalent iron (‘ferric’). Along with the product water this also produces a waste by-product, or sludge. The fact of increasing sludge production — due to higher levels of treatment and greater volume of water supply — conflicts with modern demands for environmental best practice, leading to higher financial costs. A further issue is the significant quantity of water that is held up in the sludge, and wasted. / One means of dealing with these problems is to dewater the sludge further. This reduces the volume of waste to be disposed of. The consistency is also improved (e.g. for the purpose of landfilling). And a significant amount of water can be recovered. The efficiency, and efficacy, of this process depends on the dewaterability of the sludge.In fact, good dewaterability is vital to the operation of conventional drinking water treatment plants (WTP’s). The usual process of separating the particulates, formed from a blend of contaminants and coagulated precipitate, relies on ‘clarification’ and ‘thickening’, which are essentially settling operations of solid–liquid separation.WTP operators — and researchers — do attempt to measure sludge dewaterability, but usually rely on empirical characterisation techniques that do not tell the full story and can even mislead. Understanding of the physical and chemical nature of the sludge is also surprisingly rudimentary, considering the long history of these processes. / The present work begins by reviewing the current state of knowledge on raw water and sludge composition, with special focus on solid aluminium and iron phases and on fractal aggregate structure. Next the theory of dewatering is examined, with the adopted phenomenological theory contrasted with empirical techniques and other theories.The foundation for subsequent analyses is laid by experimental work which establishes the solid phase density of WTP sludges. Additionally, alum sludges are found to contain pseudoböhmite, while 2-line ferrihydrite and goethite are identified in ferric sludges. / A key hypothesis is that dewaterability is partly determined by the treatment conditions. To investigate this, numerous WTP sludges were studied that had been generated under diverse conditions: some plant samples were obtained, and the remainder were generated in the laboratory (results were consistent). Dewaterability was characterised for each sludge in concentration ranges relevant to settling, centrifugation and filtration using models developed by LANDMAN and WHITE inter alia; it is expressed in terms of both equilibrium and kinetic parameters, py(φ) and R(φ) respectively.This work confirmed that dewaterability is significantly influenced by treatment conditions.The strongest correlations were observed when varying coagulation pH and coagulant dose. At high doses precipitated coagulant controls the sludge behaviour, and dewaterability is poor. Dewaterability deteriorates as pH is increased for high-dose alum sludges; other sludges are less sensitive to pH. These findings can be linked to the faster coagulation dynamics prevailing at high coagulant and alkali dose.Alum and ferric sludges in general had comparable dewaterabilities, and the characteristics of a magnesium sludge were similar too.Small effects on dewaterability were observed in response to variations in raw water organic content and shearing. Polymer flocculation and conditioning appeared mainly to affect dewaterability at low sludge concentrations. Ageing did not produce clear changes in dewaterability.Dense, compact particles are known to dewater better than ‘fluffy’ aggregates or flocs usually encountered in drinking water treatment. This explains the superior dewaterability of a sludge containing powdered activated carbon (PAC). Even greater improvements were observed following a cycle of sludge freezing and thawing for a wide range of WTP sludges. / Further aspects considered in the present work include deviations from simplifying assumptions that are usually made. Specifically: investigation of long-time dewatering behaviour, wall effects, non-isotropic stresses, and reversibility of dewatering (or ‘elasticity’).Several other results and conclusions, of both theoretical and experimental nature, are presented on topics of subsidiary or peripheral interest that are nonetheless important for establishing a reliable basis for research in this area. / This work has proposed links between industrial drinking water coagulation conditions, sludge dewaterability from settling to filtration, and the microstructure of the aggregates making up that sludge. This information can be used when considering the operation or design of a WTP in order to optimise sludge dewaterability, within the constraints of producing drinking water of acceptable quality.