Dissertations / Theses on the topic 'Production engineering - Environmental aspects'

As a result of rapid product development, the product life cycle has become shorter, and thus the amount of waste from discarded industrial products has risen dramatically. An awareness of the world???s environmental problems has stimulated researchers to explore the opportunities to reuse, recycle and remanufacture end-of-life products. Disassembly is a systematic approach to separating products into components or subassemblies in order to facilitate recovery of components or materials. However, the full disassembly of a product tends to be unproductive due to technical and cost constraints and product conditions after usage. Therefore, selective disassembly has been introduced as a more practical approach, where only a limited number of disassembly paths that lead to selected parts with recovering potential are considered. This research focuses on the development of a selective disassembly methodology by reversing an assembly sequencing approach. The methodology uses a step-by-step approach to generate a disassembly sequence diagram. This involves listing all the parts within the product, generating a liaison diagram to illustrate part relationships and then establishing precedence rules describing prerequisite actions for each liaison. This is followed by segregating disassembly paths that lead to the removal of selected parts or subassemblies. Then a winnowing process is applied to these paths to eliminate invalid disassembly states and transitions. The last step is to select the optimal disassembly path by using the time requirement as the main selection criterion. In order to shorten the time for carrying out the sequencing process, a javabased program that is capable of performing the first three steps has been created. The program requires three basic inputs in forms of precedence rules, and user-required part (s) and disassembly rules, prescribing which liaison (s) should be done subsequent to a particular liaison. The viability of the methodology and the program is proved through seven case studies conducted on a fishing reel, a single-hole punch, a kettle, an entire washing machine and three washing machine subassemblies. The application of the program allows the users to determine an optimal disassembly sequence in a very short time and with only basic product information as the input.

Environmental awareness and legislative pressures have made manufacturers responsible for the take-back and end-of-life treatment of their products. Therefore, manufacturers are struggling to find ways to recover maximum value from returned products. This goal can best be achieved by promoting multiple reuse programs as reuse is one of the most effective ways to enhance a sustainable engineering economy. Since the essential goal of the reuse strategy is to reuse parts, the reliability of used parts becomes a core issue. Research indicates that reuse is technologically feasible, associated with a significant manufacturing cost saving, and it does not compromise product quality. However, it is not easy to be applied in reality. There are several uncertainties associated with reuse, the most common is the uncertainty of the product???s quality after use. A widespread implementation of the reuse strategy could be triggered, subject to the availability of reliable methods to assess the useful remaining life of parts. The evolution of such a methodology would play a pivotal role in making decisions on the supply chain process and the recovery value of returned products. Reliability assessment by life cycle data analysis is the basis of this research. The proposed methodology addresses the problem of reliability assessment of used parts by considering two important aspects. It performs statistical as well as condition monitoring data analysis for decision-making on reuse. The analysis is carried out in two stages. Firstly, a wellknown reliability assessment procedure, the Weibull analysis, is applied to analyse time-tofailure data to assess the overall reuse potential of components. In the second stage, the used capacity (actual life) of components is determined by analysing their operating history (condition monitoring data). The linear and nonlinear regression analysis, Kriging procedures and artificial neural networks (ANN) are employed in this stage. Finally, the Weibull analysis and ANNs are integrated to estimate the remaining useful life of components/assemblies of a product at the end of its first life cycle. The model was validated by using life cycle data from consumer products.

Bibliography: leaves 123-130. The literature search and the findings from the investigation have been used to provide recommendations for a sector specific cooperative approach using regulation, self-regulation, voluntary agreements, economic incentatives and educational/information strategies to promote and acheive cleaner production in the South Australian foundry industry.

Thesis (MIng)--University of Stellenbosch, 2003.
ENGLISH ABSTRACT: TheSouthAfrican economy islargely dependant on small enterprisesas a valuable source of job creation, gross domestic product as well as product development and innovation, However, unfortunately there existsan extremeiy high failure rate among small businesswith 20%of startup businessesfailing within the firstyear of operation, and an almost 60% failure rate within the first6 years of existence, Thesestatisticshave initiated several research studies,and have been the focus of many businessbooks, in itseif, creating a vast industry of small businesssuccesstools and quick fix solutions, When considering the high failure rates of small businesses,the concepts surrounding sustainable development come into question by pure method of association, Sustainable development issueshave become a top priority globally and have moved up the corporate agenda in recent years. When trying to "marry" these two concepts, questions arise regarding the effect of integrating sustainability principles and management systems,with contemporary small businessstrategy. Theaim of thisstudy isto investigate existingcritical successmodels and to integrate some simple initial stages of sustainable development business strategy within these models. Expectantly, some of the principles contained in the formalisation of management systems that address sustainability issues,could be incorporated in traditional management models in an attempt to identify possible interventions and tools that might positivelyimpact on the successrate of small businessenterprises. These concepts would be tested by means of implementing a formal environmental management system (based on the ISO 14001standard) as an initial approach to addressingsustainabilitygoals, as a case study, The successful implementation of an ISO 14001 environmental management system at this small businessenterprise, realised several advantages for the company, and have been used to adapt traditional management models to include for some of the simple concepts of sustainable development.
AFRIKAANSE OPSOMMING: Die Suid Afrikaanse ekonomie is in 'n groot mate afhanklik van klein besighede as 'n waardevolle bron van werkskepping, bruto binnelandse produk, asook van produk ontwikkeling en innovasie, Des nieteenstaande, bestaan daar ongelukkig 'n baie hoe faling syfer onder klein besighede, met 20%van aanvangsbesighede wat mislukbinne die eerste jaar van bedryf en ongeveer 60%van besighede wat mislukbinne die eerste 6jaar van bestaan. Hierdie statistieke het reeds verskeie navorsingstudiesgeinisieer en was reeds die tema van verskeie boeke, wat opsig self 'n reuse industrie genereer van sake sukseshandleidings en kits oplossings vir verskeie probleme, Wanneer hierdie hoe falings statistieke onder klein sake ondernemings oorweeg word, bevraagteken mens die konsepte rakende volhoubare ontwikkeiing, bloot as gevolg van assosiasie,Volhoubare ontwikkeling het in die laaste paar jaar baie aandag geniet op die prioriteitsagendas internationaal, asook van verskeie korporatiewe agendas. As gepoog word om hierdie twee konsepte met mekaar te vereenselwig, ontwikkel daar verskeievrae rakende die effek van die integrering van volhoubare ontwikkelingsbeginselsen verwante bestuurstelsels,met bestaande kiein sake onderneming strategie, Die doel van hierdie studie isom bestaande suksesmodelIe vir klein sake ondernemings te ondersoek, en om sommige van die begin fase beginselsvan volhoubare besigheids strategie, met mekaar te integreer. Daar sou verwag kon word dot sommige van .die konsepte bevat in die formaiisering van bestuurstelselsrakende volhoubare ontwikkeling, ook geinkorporeer kan word binne bestaande traditionele bestuursmodelle, in 'n poging om moontlike ingrypings en gereedskap te identifiseer wat 'n positiewe impak kan he op die suksessyfersvan kleinsake ondernemings. Hierdie konsepte is getoets aan die hand van 'n implimentering van 'n formele omgewingsbestuurstelsel(gebasseer op die ISO14001standaard) as 'ngevalle studie, wat die begin benadering vorm om die doelwitte van volhoubaarheid aan te spreek. Die suksesvolleimplimentering van 'n ISO 14001omgewingsbestuurselsel by 'n klein sake onderneming het verskeie voordele vir hierdie maatskappy tot gevolg gehad. en is gebruik om tradisionele suksesmodelleaan te pas, om voorsiening te maak vir sommige van die konsepte rakende volhoubare ontwikkeling.

Some aspects of the presence of systemic endophytic fungi in agriculturally important New Zealand grasses were studied in relation to plant breeding. Seedling resistance to adult Argentine stem weevil feeding in perennial ryegrass, Italian ryegrass and tall fescue was found to be related to the presence of their respective Acremonium endophytes in the seed rather than to plant genetic resistance. In addition a study of perennial ryegrass revealed that this resistance was independent of endophyte viability. The seedling resistance conferred by the endophyte of Italian ryegrass was found to be beneficial for field establishment. This endophyte differs from that in perennial ryegrass and tall fescue in that it does not confer resistance to Argentine stem weevil on mature plants, but only on seedlings. The extent of plant genetic seedling tolerance to adult Argentine stem weevil feeding was limited to broad inter-specific differences, with tall fescue more tolerant than perennial ryegrass and both of these more tolerant than Italian ryegrass. This ranking corresponds with previous observations on feeding preference on mature plants. A study of factors affecting the concentration of endophyte mycelia in infected seed of perennial ryegrass revealed that plant genetic factors had little effect. The major factors studied were: 1) the endophyte concentration in the maternal parent plant directly influenced the endophyte concentration in the seed. 2) nitrogen fertilizer applications to a seed crop reduced the concentration of mycelia in the seed, with earlier applications having a greater effect. 3) application of the fungicide propiconazole (Tilt) to a seed crop reduced the endophyte concentration in the seed. 4) the endophyte concentration in the seed was found to directly influence the endophyte concentration in seedlings, six month old plants and that of seed harvested from a first year seed crop. As there have been no previous reports of tetraploid perennial ryegrass cultivars with endophyte an experiment was conducted to determine if these could be developed by the standard procedure of colchicine treatment. The results revealed that endophyte was retained following colchicine treatment.

This thesis estimates the impacts of rooftop photovoltaic (PV) capacity on electricity generation and CO2 emissions in America's Pacific Northwest. The region's demand for electricity is increasing at the same time that it is attempting to reduce its greenhouse gas emissions. The electricity generated by rooftop PV capacity is expected to displace electricity from fossil fueled electricity generators and reduce CO2 emissions, but when and how much? And how can this region maximize and focus the impacts of additional rooftop PV capacity on CO2 emissions? To answer these questions, an hourly urban rooftop PV generation profile for 2009 was created from estimates of regional rooftop PV capacity and solar resource data. That profile was compared with the region's hourly fossil fuel generation profile for 2009 to determine how much urban rooftop PV generation reduced annual fossil fuel electricity generation and CO2 emissions. Those reductions were then projected for a range of additional multiples of rooftop PV capacity. The conclusions indicate that additional rooftop PV capacity in the region primarily displaces electricity from natural gas generators, and shows that the timing of rooftop PV generation corresponds with the use of fossil fuel generators. Each additional Wp/ capita of rooftop PV capacity reduces CO2 emissions by 9,600 to 7,300 tons/ year. The final discussion proposes some methods to maximize and focus rooftop PV impacts on CO2 emissions, and also suggests some questions for further research.

Detta examensarbete syftar till att utveckla ett nytt sätt att använda betong för inredningsändamål. Betong har alltid använts i större byggnader, infrastruktur och andra kategorier. Nyligen började den moderna inredningen använda betong inomhus, till exempel som bänkskiva eller som en hylla. Arbetet fokuserar på en huvudfråga: Är betong ett bra materialval för inredning? För att besvara denna fråga bestämdes några punkter för att komma till huvudfrågan. Följande punkter behövde testat och analyserad för att komma till svaren:    - Beräkna och testa betongens hållfasthet    - Testa slagtålighet    - Analysera hur betong reagerar med kemikalier med olika pH-värde    - Förhållandet mellan miljö och betong    - Studera produktionen av betong Laborationstest, litteraturskällor och fältstudier användes som metoder för att få ett resultat av ovan nämnda punkter. Resultaten visar att betong kan användas som inredningsändamål och kan användas i större utsträckning än vad som är fallet idag. Sammanfattningsvis är betong ett bra material som används för inredningsändamål och den framtida tekniken kommer att minska koldioxidutsläppen som följer med produktionen av betongen. Det kommer att göra betong ännu bättre som material att använda i framtiden.
The following thesis aims to develop a new way to use concrete as interior material. Concrete has always been used in larger scale buildings, infrastructure and in other categories. Recently the modern interior design started to use concrete indoors for example as countertop or as a shelf. This thesis focuses on one main question: is concrete a good material choice for interior use. To answer that question, we decided to have sub questions to help to get to the main question. The following questions needed test and analysis methods to get to the answers:    - Calculate and test the strength of concrete    - Test impact resistance    - Analyze how concrete reacts with chemicals with different PH-values    - Study the production of concrete    - Relation between environment and concrete Lab tests, literature sources, and field studies was used as methods to answer those questions. The results shows that concrete can be utilized as interior material and can be used to a greater extent than is the case today. In conclusion concrete is a good material as used for interior purposes and the future technology will decrease carbon dioxide emissions that comes with production of the concrete. That will make concrete even better as material to use in the future.

This work consists of two distinct and separate sections with differing aims and outcomes. Section A is the critical review, which provides a context for the published work presented in Section B. Section A, the critical review, summarises the current literature in the subject area of environmental aspects of river management and sets the research portfolio in context. The physical landscape has been increasingly influenced by a variety of economic and social changes in recent history. During these approximately 6,000 years, human impact on river systems has been substantial and widespread. The environmental changes, that have stressed river systems, have also damaged their value for both human use and environmental functions. Some of these stresses include changes in water quality and quantity, morphological modifications of the channel and/or floodplain, decline of native species and the introduction of alien species. This has led to changes in current river management philosophy, issues and techniques. Section n, the research portfolio of published work submitted as part of this thesis, focuses on the management of some aspects of environmental change within river systems, particularly problems relating to river rehabilitation and the introduction of invasive riparian plant species. Each published paper has its own individual abstract, summarising the key finding of the research. The research portfolio can be divided into three broad sections. The first section, the main published work, includes those papers approved by the University Research Committee as part of the Registration for the degree of PhD by Published Work in May 2000. These papers form the key part of the thesis. They are introduced in the critical review in the blue text boxes, in order of significance to the text discussed and not in chronological order. They are presented in full in the appendices (numbers as shown below) printed on light blue paper. The next section relates to additional relevant published work. These papers are also submitted as part of this thesis, but are considered to be secondary as a result of their date of publication, i.e. prior to 1995. In order to distinguish these papers clearly from the key papers, they are introduced in the critical review in green text boxes and presented in full in the appendices (numbers as shown below), printed on light green paper. The candidate's approximate contribution and the nature of this contribution to each joint paper have been indicated as a percentage and are shown on the title page of each appendix. The third part is other supporting material and is referred to in the critical review through inclusion of orange-brown text boxes. Since these publications consist mainly of consultancy reports and edited books, they are NOT submitted as part of this thesis and are not presented in full in the appendices. If necessary, this material can be made available to the internal and/or external examiners before or during the viva.

The scarcity of fossil fuel and its environmental impact have shifted the world focus on green innovations At a time when the use of fossil fuel means increasing energy scarcity and an environmental crisis in the world in which we live, we need green innovations now more than ever. Growing attention has been drawn to the use of biofuels, such as bioethanol and biodiesel, which have gradually come to make up part of the total energy supply. Uncertainties about the environmental and ecological aspects of the production and consumption of biofuel still exist despite its rapid development. A life cycle analysis (LCA) evaluates the two principal functional parameters 1) energy efficiency and 2) Greenhouse Gas (GHG) balance of different feedstocks for biodiesel production from the cradle to the grave. By accounting a life cycle analysis stage by stage, we can ascertain the change in GHG emissions and energy demand that result from the various uses of feedstocks for the production of biodiesel. In this thesis, various life cycle analysis models are reviewed and evaluated with emphasis on specific biofuels. Different LCA models depend on different LCA calculation under different situations, including GREET, LEM, SimaPro, etc. The software SimaPro was used to compare the life cycle GHG emissions and energy demand from conventional petroleum fuels and several hydro-processed renewable green diesels. A consistent methodology was used for selected fuel pathways to facilitate relatively equitable comparisons. The building of life cycle flow tree in SimaPro combined the input and output with an emphasis on the following stages 1) raw material farming and acquisition, 2)liquid fuel production, 3)transport, 4)refueling, 5)liquid fuel conversion to biodiesel and 6) end uses. Consistent impact assessment methods were chosen for simulation, equitable comparisons and comprehensive analysis of selected fuel pathways for the calculation of Global Warming Potential (GWP) and Cumulative Energy Demand (CED). However, the results of the entire lifetime estimates vary dramatically in production chains, which make it difficult to take a holistic view about energy intake and yields, economic costs and values, environmental impacts and their benefits. Apart from the diversity in system boundaries and life cycle inventories, a variance in terminologies and the limitations of interdisciplinary communication are the main factors that affect the quality of the results.
published_or_final_version
Mechanical Engineering
Master
Master of Philosophy

The floating production unit HLNG FPSO-1 has been evaluated with respect to its energy consumption and emissions to air, and improvement potentials within the same context have been suggested. The thesis describes theory of combustion of natural gas, emission calculations, energy consumption of compressors and theory of fuel gas consumption for gas turbines. A literature study of LNG processes suitable for offshore applications has also been included. The CO2 emissions from the HLNG FPSO-1 add up to about 6% of the CO2 emissions from the Norwegian oil and gas industry (2005), which is a noticeable amount. However the energy content in the LNG produced over one year from the FPSO-1 count for ca 35% of the yearly energy consumed related to oil and gas extraction on the Norwegian continental shelf. This illustrates that even though floating LNG production is energy intensive and the resulting amounts of greenhouse gas emissions (as CO2) are substantial, the LNG holds significant amounts of energy, which is a result of the 600-fold reduction in volume when the natural gas is liquefied. Two different availabilities of the topside processes FPSO-1 exist and are calculated by Det Norske Veritas. The lower availability is based on a no-flare philosophy, which is considered not to be relevant for the project in the further development. The reason for this is that a strict no-flaring philosophy is not desirable from an operational point of view, and that duplication of every equipment item which handles hydrocarbon streams is not a realistic design alternative. Therefore the higher availability which allows some flaring during normal production is used for all the suggested improvement potentials. Based on two different future oil prices (a high and low scenario), the value of the LNG produced, as well as the value of the additional LNG produced as a result of higher availability of the FPSO-1 are calculated. Two design changes of the LNG liquefaction process as a result of a lighter feed gas composition are described and discussed in the context of energy consumption and emissions to air. Both design changes have the possibility of saving more than 10 MW power in total. Also, the implications of eventual necessary compliance with the Equator Principles are discussed. The project may find that certain guidelines or philosophies given by institutions financing parts of the project must be followed (such as use of Best Available Technology), and should evaluate these eventual restrictions when financial institutions are selected for the project. The further development of the project with the goal of making the topside processes on the FPSO-1 as energy efficient as possible (thereby saving operational costs and reducing the impact on the environment), should evaluate the feasibility of implementing the design changes suggested in the thesis from a more extensive technical and economical point of view.

Denna rapport är resultatet av ett examensarbete utfört vid Institutionen för industriell och ekonomisk utveckling vid Linköpings universitet på uppdrag av konsultbolaget Sustainia AB. Lean produktion, ofta benämnt Lean, har det senaste decenniet blivit en allt mer attraktiv produktionsfilosofi för att minska kostnader och öka kundnöjdhet genom förbättrad leveransservice och effektivare flöde. Ett flertal författare har påpekat att införandet av Lean direkt kan förbättra ett företags miljöprestanda, främst till följd av det minskade slöseri som Lean avser ge upphov till. Vidare finns studier som visar att vissa möjligheter till förbättringar och kostnadsbesparingar riskerar att gå oupptäckta om verksamheten ses ur ett strikt Lean-perspektiv. Med ett miljösynsätt finns dock chans att dessa blir upptäckta. Detta indikerar att såväl kostnads- som miljömässiga fördelar kan nås genom en integration av arbetet med Lean och miljöaspekter.

Syftet med detta examensarbete har varit att undersöka hur ett företags arbete med Lean respektive miljöaspekter påverkar varandra för att ta reda på om och hur väl de båda arbetssätten skulle kunna fungera tillsammans. Om det visade sig att en integration av Lean och miljö vore möjlig och fördelaktig ur affärsmässig synvinkel skulle sedermera ett förslag tas fram på hur en sådan modell skulle kunna se ut. Arbetets syfte har uppfyllts genom en kombination av litteraturstudier och intervjuer. Fyra svenska företag som arbetar enligt Lean och även har ett uttalat aktivt miljöarbete intervjuades gällande sitt sätt att arbeta med Lean och miljöfrågor samt hur de såg på en eventuell integration av de två arbetssätten.

Utifrån resultaten från litteratur- och intervjustudien kan konstateras att flera av grundtankarna inom såväl Lean som miljöarbete stöder varandra. Inom båda arbetssätten ses kontinuerliga förbättringar och eliminering av slöseri som viktiga inslag, och båda främjar en organisationskultur där personalen uppmuntras att lösa problem och förbättra företagets prestation. Vissa enskilda verktyg inom Lean riskerar emellertid att ha en negativ inverkan på företagets miljöprestanda, något som i många fall dock kan avhjälpas genom god planering.

Till ett företags miljöarbete kan Lean bidra med ett proaktivt förhållningssätt och strukturerat arbetssätt och därmed få organisationen att arbeta mer förebyggande och långsiktigt med miljöfrågor. De intervjuade företagen ansåg att Lean generellt hade en positiv inverkan på deras miljöarbete, även om de inte hade gjort någon utvärdering av hur arbetet med Lean påverkat deras miljönyckeltal. De kvantitativa data som erhölls från litteraturstudien pekade på att arbete med Lean kan leda till en direkt minskning av företagets miljöpåverkan inom flera områden. Med utgångspunkt i dessa kvantitativa och kvalitativa data anser författarna således att det finns starka och tydliga tecken som visar på att Lean kan ha en positiv inverkan på miljörelaterade nyckeltal. Ett aktivt miljöarbete kan å sin sida bidra till arbetet med Lean genom att besparingsmöjligheter, som annars skulle riskerat att förbli oupptäckta, uppdagas.

Studien visade vidare att det inte bara är möjligt att integrera arbete med Lean och miljö, utan att en sådan integration dessutom har potential att vara fördelaktigt ur såväl ett ekonomiskt som ett miljömässigt perspektiv. En integrering kan minska risken för suboptimeringar, och synergieffekter kan erhållas som innebär att större framgångar kan uppnås än vad som skulle ha varit möjligt om arbetet med Lean och miljö hade bedrivits isolerat. Med vetskapen om att en integration är möjlig och har potential att vara fördelaktig ur företagsekonomisk och miljömässig synvinkel utarbetade författarna en modell för hur Lean och miljöarbete kan bedrivas integrerat. I samråd med Sustainia AB bestämdes att denna modell skulle kallas Green Lean, vilket således åsyftar en miljöanpassad, ”grön” form av Lean.

This report is the result of a master thesis written at the Department of Management and Engineering at Linköping University commissioned by the consultancy firm Sustainia AB.

Lean production, also known as Lean, has during the last decade increasingly become a more attractive production philosophy for decreasing costs and increasing customer satisfaction by improving customer service and obtaining more efficient production flows. Several authors have pointed out that Lean has the potential to directly improve the environmental performance of a company, mostly by decreasing waste generation. Further, there are studies showing that some possibilities for improvement and cost savings risk not being discovered if the operations are seen strictly from a Lean perspective. When an environmental perspective is included there is a chance that these improvements and cost savings are discovered. This indicates that both environmental and cost related advantages might be achieved by integrating the Lean approach with that of the environment.

The purpose of this master thesis was to investigate how the work with Lean and environmental aspects affect one another. If applying the two principles together was shown to be both possible and beneficial from a business point of view, the authors would propose how these two concepts could be integrated into a single model. A combination of literature studies and interviews were used to fulfill the purpose. Four Swedish enterprises, which work according to the Lean principles and also have an active environmental profile, were interviewed about their way of working with the two approaches, as well their views on an integration of these.

From the findings in this study the authors concluded that several of the fundamental concepts concerning Lean and environmental aspects support each other. Within both, continuous improvements and waste elimination are seen as important components, and they both support an organisational culture where the personnel are encouraged to solve problems and improve the performance of the company. Conversely the authors found that there is a risk that certain of the Lean tools risk having a negative influence on the company’s environmental performance. However, in many cases this can be avoided by proactive planning.

Lean can contribute to a company’s environmental work by its proactive approach, structured way of operating and long-term way of thinking. In general the interviewed companies regarded Lean as having a positive influence on their environmental work, even though none of them had carried out an evaluation on how their work with Lean affected their environmental key performance indicators. The quantitative data obtained from the literature study indicates that Lean can lead to a direct decrease of a company’s environmental impact within several areas. As a result of these qualitative and quantitative data the authors of this thesis have found clear indications showing that Lean might have a positive impact on environmental key performance indicators. An active environmental work can also contribute to the work with Lean. Potential cost saving, which might not have been discovered with the Lean perspective, can be revealed when the organisation is studied from an environmental point of view.

The study further showed that it not only is possible to integrate Lean and environmental work, but that it also has potential to be beneficial from both a business and an environmental standpoint. An integration of Lean and environmental issues can reduce the risk of sub optimisations, and synergies can be achieved, meaning that the two systems can accomplish more together than they would in isolation. With this knowledge, the authors composed a model for how Lean and environmental work can be practised and integrated. In consultation with Sustainia AB it was decided that this model should be called Green Lean, which hence refers to an environmentally favourable, “green”, version of Lean.

The concept of sustainable development is receiving a great deal of attention in industry. However, the operational processes for industrial environmental management are still at an early stage of development and despite the best efforts of operations management and environmental specialists a great many products and services continue to be unsustainable. This presents threats to society and risks for survival to manufacturers. The purpose of the Thesis is to accelerate environmental improvements through the uptake of Cleaner Production concepts by developing a methodology for guiding manufacturing enterprises. The tenets of the proposed methodology include: o oo Reliance on a strategic approach ooo Development of an implementation path similar to those used in introducing other major culture and technology changes ooo Culture and policy change are strategically generated from within manufacturing organisations Specifically, the main objectives of the Project are: 1. to invent a relatively easily implementable methodology for planning for sustainability for manufacturing enterprises of all sizes 2. to address the major industrial environmental management issues at all levels within the enterprise as one seamless process 3. to configure the methodology so that it may be incorporated into an existing body of knowledge, e.g., manufacturing management/manufacturing engineering 4. to minimise complexities by standardising key concepts and terminology The Thesis integrates Sustainability and Cleaner Production concepts, systems and technologies and performance indicators with a planning model to arrive at what has been termed as " the Strategy Development and Implementation with Cleaner Production" process. This solution addresses the key point of integrating Cleaner Production concepts ii with the manufacturing planning processes, but just as importantly, it also establishes the links between the steps from strategy initiation through to implementation, from the boardroom down to the factory floor. The main modules of the work are: o oo establishing relationships between strategic, business and manufacturing plans using the concepts of Sustainability, Eco-efficiency and Cleaner Production ooo development of links between planning and operations using the concepts of Industrial Ecology and Life Cycle Management ooo development of a classification system, referred to as a Cleaner Production toolkit, to promote optimum selection of hard and soft systems and technologies ooo development of appropriate Cleaner Production Indicators to complete the loop.

Water, otherwise known as the pool of life, is the very essence of all living things and as such is vital for survival, whether for living beings, social, economic development or for environmental sustainability. However, its continuing existence is severely threatened for future as a result of climate change, carbon footprint, population growth, environmental damage, combined with natural disasters like droughts and floods. The prospect of an alternative solution such as desalination of sea or brackish water to counter the limit on conventional water resources such as groundwater, which cannot meet demand, is therefore very promising, particularly in arid and semi-arid regions where water scarcity and impaired quality prevails. Consequently, desalination technology has now become a burgeoning industry in North Africa or southern Mediterranean countries, such as in Libya. However, evidence suggests that as a result of by-products being discharged directly into the sea, particularly from coastal desalination plants, the physico-chemical parameters of the receiving water are changing and posing a threat to marine ecosystems. As a result of studies conducted on these parameters to analyse the brine emitted from the Zwuarah and the West Tripoli distillation plants (ZWDP & WTRIS) on the Libyan coastline, evidence shows there is a significant positive correlation at both sites between the biological data and physico-chemical parameters (rs=0.673; p=0.002) and (rs=0.637; p=0.003), which is a clear indication of the impact of brine disposal from both plants on the marine environment. For most of coastal desalination plants on the Libyan coastline, the most practical and least expensive brine disposal option is to discharge it into the sea. It is necessary therefore, to effectively manage desalination reject brine in order to ensure more efficient disposal and reuse. Therefore, it is suggested that experimental studies are aimed for dual benefit of on-site generation of sodium hypochlorite through brine electrolysis and to recover minerals and NaCl from the brine using evaporation ponds, while protecting the environment. Following the first experiment, the outcome of brine utilisation showed a significant production of NaOCl using graphite electrodes (MCCA 1.82 gr/m3). At interelectrode spacing 2 cm and 4 cm, the power consumption was higher, with a greater concentration of sodium hypochlorite generation varying between 10-25 kw/m3 (573-2140ppm) and 29-24 kwm-3 (572-2600ppm) than at interelectrode spacing 6cm 17-13 kwm-3 (350-1790ppm). Consequently, the selection of an optimum electrical consumption level is key in establishing the best scenario in terms of economy and efficiency. Subsequent to the second experiment of brine evaporation in the ponds, results showed that the evaporation rate in August was lower than in September (9.06 mmday-1, 14.63 mmday-1) respectively. The results of the SEM/EDS test showed that due to elevated surges of Na+ and Cl-, halite (NaCl) was the main mineral evident during crystallisation of the salt samples. Hence, the two experiments reveal that brine can be recycled productively, while protecting the environment.

This study aims at presenting a strategic supplier evaluation model that can assist Cederroth in strategic supplier selection and give indications on potential areas for strategic supplier development. The evaluation model aims at assessing supplier performance also with respect to environmental aspects. The final model has been developed through five steps, five models, with starting point in a theoretical review and basic empirical data. Following the model was developed through four iterations of workshops, interviews, weighting and case studies. The final model includes 7 criteria categories and 41 criteria whereas one category including 7 criteria assesses a supplier’s environmental performance.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2008.
Includes bibliographical references.
This study models and assesses the current and future fossil fuel consumption and greenhouse gas impacts of ethanol produced from three feedstocks; corn grain, corn stover, and switchgrass. A life-cycle assessment approach with an integrated Monte Carlo uncertainty analysis is applied to each of these three bioethanol pathways. Incorporating a Monte Carlo uncertainty analysis within a life-cycle model enables one to account for system variability within the agricultural, technological, and geographic arenas. This results in a range of energy and greenhouse gas impacts rather than previous single-valued estimates. This uncertainty analysis brings greater clarity to the ethanol debate through evaluating the probability of previously published life-cycle assessment net energy results, from reports such as Farrell, Wang, Shapouri, and Pimentel. Lifecycle assessment net energy results show corn grain ethanol to have a positive value when DDGS coproducts are included within the assessment boundary and a slightly negative value when they are not. The system net energy value and GHG emissions are also sensitive to system input assumptions and geographic location. For lignocellulosic ethanol produced from corn stover and switchgrass, a positive net energy value and reduced GHG emissions are seen when compared to gasoline. In addition to net energy results and system GHG emissions, the petroleum displacement and land use impacts for an expanding and evolving ethanol industry are also evaluated.Corn grain, corn stover, and switchgrass-based ethanol potential production levels are also analyzed. It was determined that 55-65 billion liters per year of corn grain ethanol could potentially be produced in the next 10 years, consuming 30% of future US corn grain production. Corn stover and switchgrass have the potential to produce 25-35 and 10-20 billion liters per year of ethanol, respectively.
(cont) These ethanol production results were then applied to assess the feasibility and environmental impact of achieving the new Renewable Fuels Standard, of producing 136 billion liters of renewable fuels by 2022. This study concluded that while the scale is potentially feasible from these three feedstocks, the timeline to achieve this scale would be very challenging given the cellulosic ethanol technological and economic advances that are still needed.
by Tiffany A. Groode.
Ph.D.

High speed twist drills are probably the most common of all metal cutting tools and also the least efficient. In this study, detailed research was undertaken into aspects of drill performance and ways in which drilling could be improved in short hole depths of up to two diameters. The work included an evaluation of twist drill geometry and grinding parameters. It was established that errors in point grinding lead to increased hole oversize and reduced drill life. A fundamental analysis was made to establish predictive equations for the drill torque and thrust using modified orthogonal cutting equations and empirical data. A good correlation was obtained between actual and predicted results. Two new techniques for extending twist drill life by the use of coolant feeding holes and also the application of titanium nitride coatings were evaluated. Both methods were found to have potential for improving drill performance. A completely new design of carbide tipped drill was designed and developed. The new design was tested and it compared favourably with two commercially available carbide tipped drills. In further work an entirely different type of drill point geometry was developed for the drill screw. A new design was produced which enabled the drilling time to be minimised for the low thrust forces that were likely to be used with hand held power tools.

Thesis (MTech (Business Administration))--Cape Peninsula University of Technology, 2017.
This research study investigates how environmental tools such as Resource Efficiency and Cleaner Production (RECP) can contribute to sustaining and supporting economic growth in South Africa. Resource optimisation is crucial when considering the concept of sustainable development. It also contributes to addressing the challenges of global warming and climate change, which in turn threaten industrial growth and sustainability in the long term. The study places emphasis on the barriers that prevent industry from implementing RECP recommendations, and identifies opportunities that could potentially reposition businesses should they consider implementation. It also promotes other sustainability tools that are available through collaboration with international entities, and this could be of great benefit to the South African industry. Factors of unemployment and urbanisation restricts national growth to some degree, hence the study explores how RECP can contribute to job retention by introducing new resource optimisation methodologies for the manufacturing sector, Moreover, it examines the imbalance between the demand as well as limitations of these resources. Through the compilation of data collated from questionnaires completed by industry, government and civil society participants, this study looks at achieving a balance between environmental sustainability and growth. It also looks at aligning this balance with the integration of specific economic and environmental policies, which also includes social aspects. What comes through significantly in this research is the lack of awareness within industry in terms of RECP, as well as the importance of prioritising the uptake of environmental initiatives to ensure that industry is compliant with the stringent policies and legislation designed by government to drive the sustainability process. Consequently the study shows that communication between public and private sector, as well as the awareness raising and marketing of sustainability to consumers need to be improved. An analysis of the various government support mechanisms is conducted, in respect of how industry could potentially leverage growth and drive positive change within their businesses. In addition to RECP, emphasis is placed on other Sustainable Consumption and Production (SCP) initiatives and tools that could possibly entrench sustainable practices and help with their incorporation into their business strategies.

Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2002.
Includes bibliographical references (p. 145-148).
A major drawback of the traditional output queuing technique is that it requires a switch speedup of N, where N is the size of the switch. This dependence on N makes the switch non-scalable at high speeds. Input queuing has been suggested instead. The introduction of input queuing creates the necessity for developing switching algorithms to decide which packets to keep waiting at the input, and which packets to forward across the switch. In this thesis, we address various algorithmic aspects of switching. We prove in this thesis, that many of the practical switching algorithms still require a speedup to achieve even a weak notion of throughput. We propose two switching algorithms that belong to a family to which we refer in this thesis as priority switching. These two algorithms overcome some of the disadvantages in existing priority switching algorithms, such as the excessive amount of state information that needs to be maintained. We also develop a practical algorithm that belongs to a family to which we refer in this thesis as iterative switching. This algorithm achieves high throughput in practice and offers the advantage of not requiring more than one iteration, unlike other existing iterative switching algorithms which require multiple iterations to achieve high throughput. Finally, we address the issue of using switches in parallel to accommodate for the need of speedup. We study two settings of parallel switches, one with standard packet switching, and one with flow scheduling, in which flows cannot be split across multiple switches.
by Saadeddine Mneimneh.
Ph.D.

Many decision-making situations today affect the safety of individuals and the environment,for instance hazardous waste management. In practice, many of these decisions are madewithout an overall view and with the focus on either the environment or safety. Now and then the areas of regulation are in conflict, i.e. the best alternative according to environmental considerations is not always the safest way and vice versa.A tool for taking an overall view within the areas of safety and environment would simplify matters and provide authorities and industry with a better basis for their work. This thesis forms part of a project which aims to develop a framework tool giving this overall view and supporting decision-making in which the issues (areas) of environment, safety, ethics and costs are all integrated. By developing a framework tool, different areas of interest could be taken into consideration more easily when a decision is to be made and could also help develop legislation and policy locally (at an industry or company), nationally and internationally. The project also aims to provide knowledge about different destruction/decommission methods, their good and bad points and their consequences, in order to provide different actors with a better basis for decision-making. This thesis focuses on development of the framework. The scope of the studies was restricted to environment, ethics and personnel safety due to the extent of the work and time limitations. In the next part of the project, the areas of costs and evaluation will be studied and a first draft of the framework tool will be presented. In order to develop the framework tool, two case studies were carried out here: an environmental analysis involving a life cycle assessment and an ethical analysis. With the help of these analyses, three different methods of destruction of ammunition were compared: Open detonation, modelled both with and without recovery and recycling of metals; incineration in a static kiln with air pollution control combined with recycling of metals, modelled with two different levels of air emissions; and a combination of incineration with air pollution control, open burning, recovery of some energetic material and recycling of metals, giving a total of five options. Every method of destruction of energetic material, i.e. explosive waste or ammunition, results in environmental impacts in both the short and long term. These environmental impacts have direct or indirect impacts on safety, quality of life, the economy, etc., now and in the future, locally and globally. Life cycle assessment revealed two factors of importance for reducing the environmental impacts: Recycling the metals and air pollution control. As a consequence of controlling these potential negative environmental impacts, safety problems might also be controlled. Ethical analysis revealed that future generations and people in foreign countries will be affected by the destruction of ammunition. When choosing a method for destruction of ammunition, this group (the general public) should thus be given special attention.
QC 20101210

The built environment contributes extensively to the overall environmental impact of society. An increasing number of tools have been developed worldwide for comprehensive environmental assessment and rating of buildings in order to make the building sector more sustainable. These tools are expected to drive and facilitate future environmental improvements and market transformation in the sector. This thesis explores different methodological aspects in tool development using experiences from two large Swedish projects, the EcoEffect and ByggaBo tools, which were developed with a high level of stakeholder participation in order to be of practical use in the building sector.   The methodological aspects explored and discussed here include an approach for systematic selection of assessment aspects (energy use, indoor air quality, etc.) in tools (Paper 3), and a systematic procedure for selecting practical indicators using theoretical (e.g. validity/environmental relevance) and practical (e.g. costs) criteria (Papers 2 and 3). An approach for simple communication of complex results is presented with examples from 26 multi-family buildings (Paper 4). This approach allows a building’s ‘environmental efficiency’ to be presented in one diagram, without weighting the two distinct assessment areas energy use and indoor environmental quality. Paper 5 discusses the contextual issue of internal use of environmental indicators in property management organisations through reviews of environmental performance evaluation and organisation theory literature and comparisons with actual case studies. The EcoEffect (Paper 1) and the ByggaBo tools are also compared and summarised.   The case studies of real buildings and experiences from the EcoEffect and ByggaBo projects allowed data collection, calculation procedures and different practical applications of such tools to be evaluated. Poor data availability sometimes limits assessments, and improved internal routines and database developments in the building sector would allow more reliable environmental assessments.   Reviews of numerous indicators in Paper 3 (and 2) and literature revealed that environmental relevance was not a key aspect when current environmental performance indicators and building rating tools were constructed. This thesis suggests that environmental relevance and systematic procedures be prioritised in order to provide robust and trustworthy tools for environmental assessment of buildings.  Recommendations, some of which are generally applicable to other environmental assessments, include selection of environmentally relevant indicators, systematic procedures for handling theoretical and practical considerations in tool development, aggregation and weighting methods, use of a life cycle perspective and inclusion of performance-based rather than feature-based indicators. Since it is likely that the information these tools provide will increasingly be used by authorities, building users, economic incentive providers such as banks, etc., the methodological developments suggested here to strengthen tool rigour are important for future tool development processes.
Utvecklingen av verktyg för miljöbedömning av byggnader är ett område som expanderat kraftigt sedan 1990-talets början. Den ökande medvetenheten om den byggda miljöns omfattande bidrag till samhällets miljöpåverkan i stort har spelat stor roll för denna utveckling. Verktygen förväntas ha en betydelsefull roll i att driva på och underlätta miljöförbättringar och omdaning av marknaden i bygg- och fastighetssektorn. Denna avhandling utforskar olika metodaspekter för verktygsutveckling och bygger på erfarenheterna från två stora svenska metodutvecklingsprojekt för miljöbedömning av byggnader, EcoEffect och ByggaBo:s miljöklassning av byggnader. Båda dessa verktyg togs fram i samarbete med ett stort antal representanter från bygg- och fastighetssektorn, då verktygen syftade till praktisk användning.   Ett antal metodaspekter utforskas och diskuteras i avhandlingen. I artikel 3 föreslås och testas ett angreppssätt för systematiskt urval av miljöaspekter som ska bedömas av ett verktyg och dessutom föreslås här och i artikel 2 ett systematiskt tillvägagångssätt för att välja indikatorer för praktiskt användning utifrån både teoretiska (t ex. validitet) och praktiska (t ex. kostnad) kriterier. Ett angreppssätt för att underlätta kommunikation av komplexa miljöbedömningsresultat presenteras genom exempel från 26 flerfamiljshus i artikel 4. Detta angreppssätt möjliggör att redovisa en byggnads ‘miljöeffektivitet’ i ett diagram utan att behöva vikta de två disparata miljöaspekterna energianvändning och innemiljö. Artikel 5 tar upp användning av miljöindikatorer för internt arbete i fastighetsförvaltande organisationer genom litteraturöversikter inom områdena utvärdering av miljöprestanda och organisationsteori samt genom jämförelser med praktiska fallstudier. Verktygen EcoEffect (artikel 1) och nuvarande version av ByggaBo:s miljöklassningssystem sammanfattas också och jämförs i avhandlingen.   Genom ett antal fallstudier av verkliga byggnader och erfarenheterna från EcoEffect- och ByggaBo-projekten utvärderas frågor som insamling av indata, beräkningsmetoder och olika praktiska tillämpningar i avhandlingen. Dålig tillgång på indata begränsar ibland möjligheterna att göra miljöbedömningar. Förbättrade interna rutiner samt utveckling av nya typer av databaser inom bygg- och fastighetssektorn kommer med största sannolikhet att underlätta miljöbedömningar i framtiden.   Granskning av ett stort antal miljöindikatorer i artikel 3 (och 2) och litteratur på området visade att när miljöindikatorer och miljöklassningsmetoder tagits fram, har miljörelevansen hos dessa sällan haft högsta prioritet. Ett övergripande mål för denna avhandling har därför varit att bidra med rekommendationer som kan stärka miljörelevansen och trovärdigheten hos liknande indikatorer och verktyg. Några av de angreppssätt som föreslås är tillämpliga mer generellt också för andra typer av miljöbedömningar; t ex. hur miljörelevanta miljöindikatorer kan väljas, hur både teoretiska och praktiska överväganden kan hanteras på ett systematiskt sätt vid liknande verktygsutveckling, angreppssätt för viktning och aggregering av resultat samt användning av ett livscykelperspektiv. Vid miljöbedömning av byggnader bör också funktionsbaserade indikatorer i första hand väljas snarare än sådana som baseras på specifika tekniska utföranden. En trolig utveckling är att nya typer av användare i större utsträckning kommer att efterfråga den information som miljöbedömningsverktyg för byggnader kan tillhandahålla. Det kan handla om t ex. myndigheter, husköpare och ekonomiska incitamentsgivare såsom banker. Av denna anledning är de frågor som rör metodutveckling och tas upp i avhandlingen, klart betydelsefulla för att stärka noggrannhet, robusthet och trovärdighet i framtida utveckling av miljöbedömningsverktyg för byggnader.
QC 20100601
Miljöklassning av byggnader
EcoEffect - miljövärdering av byggnader
Miljöstyrning med miljöindikatorer i fastighetsförvaltning

Thesis: S.M., Massachusetts Institute of Technology, Department of Biological Engineering, 2019
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 43-47).
Artificially photosynthetic systems aim to store solar energy and chemically reduce carbon dioxide. These systems have been developed in order to use light to drive processes for carbon fixation into biomass and/or liquid fuels. We have developed a hybrid-biological system that manages both genetically controlled generation of products along with the photoactivability of a semiconductor system. We show an increase in the production of ethanol, a common biofuel, through the electron transfer stimulated by biologically produced cadmium sulfide nanoparticles and light. This work provides a basis on which to improve the production of many metabolites and products through endogenously produced nanoparticles.
by Shalmalee Pandit.
S.M.
S.M. Massachusetts Institute of Technology, Department of Biological Engineering

Recently, because of the increase of environmental concerns in process design, the need to enhance conversion to product and prevent generation of wasteful byproducts in the reactor network has become urgent. This prevents high cost treatment and separation costs downstream in the process. Therefore, in this thesis I focus on making production of vinyl chloride monomer (VCM) more efficient and on possible ways of industrial organochlorine waste (OCW) recycling. In particular, in the first experiment, we investigate how catalyst and its structure can affect product output. Infrared spectroscopy and X-ray diffraction analysis were utilized to investigate the structure of the γ-Al2O3 carrier with CuCl2 catalyst on its surface. Structure of the two catalysts, HarshowX1 and MEDC-B, and their effect on the mechanism of ethylene oxidative chlorination reaction into 1,2-dichlorethane were studied. Differential thermal analysis and mass spectroscopy were applied to study the structure and the mechanism differences between the deposited and permeated CuCl2 catalysts. The second experiment deals with ecological processing and recycling methods of wasteful byproduct that can be called chlororganic wastes. Typical waste products are 1,2-dichloroethane, 1,1,2-trichloroethane, vinylidene, and vinyl chloride monomer. Polymerization and copolymerization of typical waste products with their C5-C9 fraction resulted in non-toxic polymer products that can be used in construction and road-building industries. The possibility of joint chlorine and sulfide-containing chemical wastes recycling into polysulfide oligomeric products is discussed. This comprehensive recycling allows utilizing 80-90% of all wastes generated during synthesis of chlorinated products in the chemical industry. The results of the studies aim to improve the conversion of ethylene to vinyl chloride and minimize the formation of byproducts.

Product reliability and its environmental performance have become critical elements within a product's specification and design. To obtain a high level of confidence in the reliability of the design it is customary to test the design under realistic conditions in a laboratory. The objective of the work is to examine the feasibility of designing mechanical test rigs which exhibit prescribed dynamical characteristics. The design is then attached to the rig and excitation is applied to the rig, which then transmits representative vibration levels into the product. The philosophical considerations made at the outset of the project are discussed as they form the basis for the resulting design methodologies. It is attempted to directly identify the parameters of a test rig from the spatial model derived during the system identification process. It is shown to be impossible to identify a feasible test rig design using this technique. A finite dimensional optimal design methodology is developed which identifies the parameters of a discrete spring/mass system which is dynamically similar to a point coordinate on a continuous structure. This design methodology is incorporated within another procedure which derives a structure comprising a continuous element and a discrete system. This methodology is used to obtain point coordinate similarity for two planes of motion, which is validated by experimental tests. A limitation of this approach is that it is impossible to achieve multi-coordinate similarity due to an interaction of the discrete system and the continuous element at points away from the coordinate of interest. During the work the importance of the continuous element is highlighted and a design methodology is developed for continuous structures. The design methodology is based upon distributed parameter optimal design techniques and allows an initial poor design estimate to be moved in a feasible direction towards an acceptable design solution. Cumulative damage theory is used to provide a quantitative method of assessing the quality of dynamic similarity. It is shown that the combination of modal analysis techniques and cumulative damage theory provides a feasible design synthesis methodology for representative test rigs.

This thesis looks at the role of wild pollinators in providing services to crops. Two data chapters (2 and 3) are accompanied by a modelling chapter (4) which build on the findings of the field studies. The thesis ends with an overview of the trends in pollinator populations and how these relate to the needs of farmers in the UK (chap-ter 5). It is often assumed that commercial pollinators are appropriate substitutes of wild pollinators on farms; however this view neglects the differing roles that particular pollinator taxa might play in providing pollination services. For example, crops with a long growing system may require multiple pollinators to ensure pollination throughout the season. Strawberries in Scotland have an extremely long growing season, flowering from April to August. Chapter 2 presents a study showing season-al complementarity between different pollinating taxa across strawberry farms in Scotland. Pollinators of strawberries also differed in their responses to weather pa-rameters indicating that preserving multiple pollinator taxa could ensure yields un-der different weather scenarios. The requirements of a long-growing season and ad-verse weather may be specific to strawberry production in Scotland, but the valua-tion of multiple taxa can be generalised to systems with differing needs, and also to different ecosystem services. Wild bees are not only valuable for providing complementary services to commercial pollinators, but are also valuable in the longer term as it is unknown whether com-mercial pollinators will be available in the future. There are threats to the supply of honeybees which have already triggered price rises; such supply shocks could force farmers to leave production or to seek other ways of providing pollination, including supporting wild pollinators. However farm management pressures, in particular pes-ticide use, could threaten the ability of wild pollinators to continue to support crop production. The interplay of pesticides and pollination is discussed in chapter 3 and 4. Chapter 3 presents an experiment undertaken on soft-fruit farms which had and had not used the neonicotinoid, thiacloprid, and shows that nests exposed to thia-cloprid had higher worker mortality, and lower male production than those at con-trol farms. This has implications both for pollination services now, as worker mor-tality will reduce the number of bees visiting farms, and also for the maintenance of future pollination services through decreased reproductive capacity of exposed nests. Chapter 4 uses a theoretical model to link pesticide use and habitat use to pollina-tion services, and shows that the use of commercial pollinators could mask the de-cline in wild populations, making local extinctions more likely. Chapter 5 sets out the status and extent of pollinators in the UK, along with popu-lation trends, trends in habitat and trends in pesticide use to provide an overview of how well pollination services are likely to meet the ongoing needs of crop farmers.

Environmental concern has greatly increased in magnitude within the companies of Swedish industry. Product development has become a strategic area: the environmental adaptation of products is fundamental for a decrease in environmental impact from human activities, and product development is an area of the greatest importance to the competitiveness of companies. Integrating environmental aspects into product development at operations level is needed to achieve product improvements. The theme of this thesis is how to integrate environmental aspects into product development. An overarching purpose has been to identify adequate activities and changes required for integration. Great importance has been attached to conducting changes, especially by investigating how successfully to implement support tools in product development. Qualitative research interviews have been used to collect empirical data. Conclusions on measures industrially applicable to enabling the integration of environmental aspects have been drawn, as empirical data and experiences have been accumulated. Environmental aspects give rise to new considerations in product development: causal relationships between products and environmental impact; the life-cycle approach; and, new priorities and trade-offs between function, cost and quality of products. A need for activities supporting these considerations is identified; and, preferably, several activities, concerning knowledge development, work procedures and support tools, should be applied. It is also important to identify environmental actors for providing expertise and enthusiasm in the organisation. The implementation of support tools has to be carefully considered. To guide such implementation a framework with key factors has been developed. The framework suggests a cyclical implementation process, identification of the organisational change field, and consistent management behaviour. Keys to successful implementation are goal setting, knowledge development, adequate resources, anchoring at all levels, and a focus on individuals. To stay competitive, companies need to be proactive and respond to the driving forces underlying environmental adaptation. To make possible the environmental adaptation of products, several measures are needed. The following proactive measures have been identified: Management ought to set direction with a comprehensive view on business development and physical flows in the business. Commitment to desired change must be created to make sure changes are accepted and durable. Knowledge and skills need to be developed with an action learning approach. Work procedures need to be adjusted to include environmental criteria and secure interaction between product developers and environmental experts. Support tools can support a structured approach and enable rapid progress to be attained.
QC 20100623

Thesis (MScAgric)--Stellenbosch University, 2015.
ENGLISH ABSTRACT: The world demand for animal proteins and profit-driven production has led to producing animal proteins intensively. Intensive pork production systems have traditionally had a poor image with the public, because these production systems are associated with environmental pollution. Currently, pigs are produced on highly specialised farms, and are fed concentrated (often imported) pig feed. The resulting higher production and higher animal densities contribute to an increased pollution of water, soil and air. The aim of this study is to determine the energy balance and emissions of three case studies, and to compare these results with their financial performance. The impacts will be recorded in the following impact categories: global warming potential (GWP), acidification potential (AP), eutrophication potential (EP) and Energy Use (EU). The case studies are three typical South African pig production facilities selected by the South African pork producer’s organisation (SAPPO). The production inputs, from the feed acquisition to the delivery of one kg of pig at the farm gate, were included. The three farms are located in different areas in South Africa, namely KwaZulu-Natal province (Case study 1), North-West province (Case study 2) and Western Cape province (Case study 3). The functional unit (FU) for this study is defined as 1 kg of South African pig (live-weight) at the farm gate. This study found that the GWP/FU of Case study 2 is 4 and 2 % higher than Case studies 1 and 3 respectively. The EP/FU of Case study 1 is 9 and 6 % higher than Case studies 2 and 3 respectively. The AP/FU of Case study 1 is 4 and 5 % higher than Case studies 2 and 3 respectively. The EU/FU of Case study 3 is 45 % and 16 % higher than Case studies 1 and 2 respectively. The major activities that contributed to the environmental impact categories were the slurry management activity, followed by electricity usage. The financial and environmental performance comparison did show deviations. Therefore, it is recommended that environmental and financial performance measurements be made, in order to create a true reflection of the impacts. The potential for improvement in financial and environmental performance proved to be significant in the productivity of the sow herd, as well as in the management of the piglets. The location of the production facility does not claim to hold have significant environmental or financial implications. Management of the emissions produced by piggeries can offset the impact of the piggery's location.
AFRIKAANSE OPSOMMING: Nie beskikbaar.

The World Health Organization estimated in 2013 that 768 million people lack access to improved drinking water sources. Ceramic water filters have grown in popularity over the past several decades as a point-of-use treatment option to improve water quality. Water treatment reduces the health risks from disease from microbial pollution and potentially other causes. To improve filter design, a more thorough analysis is needed of the effects of the clay and organic materials used to make ceramic water filters. The research presented in this dissertation investigates the effect of four variables on ceramic water filter performance: type of organic matter, total percent volatile matter, air drying compared to oven drying at 105°C, and organic matter particle size. Ceramic water filters were made using the two most common material compositions, clay and sawdust, and clay and rice husks. The moisture content, volatile matter content, and ash content of each material was measured. Ceramic discs 7.6 cm in diameter were made and fired to test for flow rate, porosity, and microbial removal efficiency. Ceramic bars were tested for flexural and impact strength.

Flow rate increased with increasing volatile matter, and therefore with porosity. The Carman-Kozeny equation was fitted to sawdust and rice husk flow rate data with an R² value of 0.414 and 0.970 respectively. Oven drying filters resulted in a 0.80 to 1.8 log decrease in bacterial removal. Filters produced with a mixture of 75% large (0.297–0.841 mm) and 25% small (<0.297 mm) organic particles demonstrated a 68% increase in flow rate without reduction in microbial removal compared to filters made with 100% large particles. Microbial removal efficiency decreased with increasing volatile matter content, porosity, and organic matter particle diameter. The flexural and impact strength of sawdust specimens decreased with increasing volatile matter content. Flexural strength of rice husk specimens decreased with increasing volatile matter. However, impact strength of rice husk specimens increased with increasing volatile matter. The model by Li and Aubertin (2003) was fitted to sawdust and rice husk flexural strength data with an R² value of 0.925 and 0.935, respectively.

The results presented in this dissertation provide a range of flow rate and porosity values for sawdust and rice husk filters that can be used to predict the expected microbial removal efficiency. They compose a system of standard methods to test ceramic water filters that will allow for accurate comparison of filters made with different materials and methods.

A standard methodology was developed for performing avoidance-preference tests, using Rainbow Trout (Salmo gairdneri) as the test organism. Experiments were conducted in a hydraulic channel, 9.15 m long by 0.30 m wide, partly divided along its length, and at a flow depth of 0.30 m. The design combined steep and shallow gradient characteristics. The toxicants investigated included Cu(II), Cr(III) and Cr(VI). The lowest avoidance threshold values were established at 2.1 $ mu$g/l for Cu(II) and 0.0026 mg/l and 0.026 mg/l for Cr(III) and Cr(VI) respectively while avoidance reactions increased with levels of toxicant in the channel. Similar experiments were performed with rainbow trout which were pre-exposed at sublethal levels to the toxicant, in order to assess the influence of toxic pre-exposure to the subsequent fish avoidance response. The length of pre-exposure varied between 7-20 weeks. Avoidance threshold values were correlated with safe levels of toxicant exposure.
Pre-exposed fish exhibited decreasing avoidance reactions compared to non-exposed populations. Increased tolerance to the toxicant, was suggested by the increase in avoidance threshold values with pre-exposure levels. Fish exposed to test concentrations matching their pre-exposure levels, clearly preferred this same concentration over the adjacent lower or higher test concentration.
A two mechanism avoidance model was proposed independent of toxicant used or level of pre-exposure. The toxicant concentration where the second mechanism begins to dominate was referred to as avoidance breakpoint, and was correlated to a MATC level for the toxicant in question. Olfactory responses were proposed to be associated with fish avoidance responses below the avoidance breakpoint, while hypoxic stress along with osmo- and iono regulatory stress appeared to be responsible for driving fish avoidance reactions beyond the avoidance breakpoint.
A clearance period of 7 days was sufficient to allow fish to recover normal avoidance behaviour following pre-exposure to Cr(VI) below the avoidance breakpoint.

A Neochloris oleoabundans strain screened in our lab was demonstrated to have the ability to accumulate large quantities of triglycerides, the feedstock of biodiesel production, and to remove nitrogen and phosphorus from wastewater efficiently. Box-Behnken experimental design (BBD) and response surface method (RSM) were used to study the effects of a large number of nutrients on cell growth and lipid accumulation. The optimized medium supported a lipid concentration of 641.4 mg/l and a cell density of 2.54 g/l, which were 4.5-fold and 2.2-fold of that obtained with the basic medium, modified Bristol medium (MBM), respectively. The capacity of the strain for phosphorus removal and nitrogen removal was investigated using artificial wastewater and municipal wastewater effluents. It was demonstrated that the strain could achieve near-zero residual phosphate and nitrogen at the end of cultivation when artificial wastewater contained up to 140 mg N-NO 3-/l and 47 mg P-PO43-/l. The rates of the removal of N-NO3- and P-PO4 3-, are 27.5 mg/l·d, and 9.4 mg/l·d, respectively under optimal conditions. It was observed that the nitrogen content of the wastewater effluent was not sufficient and additional nitrogen source (e.g., NaNO 3) of 70 mg/l was required for optimal cell growth, CO2 fixation, and phosphate removal.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2010.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 175-178).
The future availability of the natural resources (water and land) needed for food production is highly uncertain. Evidence shows diminishing natural resources and growing food demand throughout many parts of the world. China is one of the countries that face the challenge of managing its finite water and land resources to support their population. Difficulties mainly arise from: (1) the geographic mismatch between the location of water resources and available land; (2) a large and growing number of population; and (3) limited natural resources per capita. This thesis presents a systematic approach to evaluate the effects of water and land constraints on food production and applies it to China as a case study. Based on the basic principle of water and land balance, crop resource requirements, and per capita consumption, the assessment of natural resources limitations on food production can be formulated into an optimization model, with the objective function maximizing the number of people fed subject to resource constraints. This formulation makes it possible to systematically and efficiently evaluate the effects of natural resource constraints for such a complex and large scale study regions such as China. Even though our approach is based on the basic principle, we incorporate several significant features into the model to realistically represent the spatial and temporal heterogeneity in climate, land use, and crop requirements. Our analysis is conducted at a detailed spatial resolution of 0.5' by 0.5', includes water movement at the same resolution, accommodates the mixture of crops in people's diet, and distinguishes irrigated from rain-fed agriculture. Our optimization model presents an average long term analysis. The model is developed and calibrated to reproduce long-term observed conditions during the nominal period of 1990- 2000. We then use the model together with globally and locally available data to make future predictions of China's food production capacity during the future period of 2046-2065. These future predictions include the impacts of the South-to-North Water Diversion project and projected climate change. The future climate scenarios are taken from the general circulation model predictions and represent diverse seasonal and regional patterns. Regionally, land is a limiting factor in the south, while water is a limiting factor in the north. Our results suggest that irrigation and multiple-cropping are keys in enhancing China's food production capacity to support increasing population. The spatial and seasonal distribution of rainfall changes is critical for agriculture in meeting future food requirements under climate change.
by Piyatida Hoisungwan.
Ph.D.

Case studies in copper-alloy rolling mill companies showed that existing planning systems suffer from numerous shortcomings. Where computerised systems are in use, these tend to simply emulate older manual systems and still rely heavily on modification by experienced planners on the shopfloor. As the size and number of orders increase, the task of process planners, while seeking to optimise the manufacturing objectives and keep within the production constraints, becomes extremely complicated because of the number of options for mixing or splitting the orders into batches. This thesis develops a modular approach to computerisation of the production management and planning functions. The full functional specification of each module is discussed, together with practical problems associated with their phased implementation. By adapting the Distributed Bill of Material concept from Material Requirements Planning (MRP) philosophy, the production routes generated by the planning system are broken down to identify the rolling stages required. Then to optimise the use of material at each rolling stage, the system generates an optimal cutting pattern using a new algorithm that produces practical solutions to the cutting stock problem. It is shown that the proposed system can be accommodated on a micro-computer, which brings it into the reach of typical companies in the copper-alloy rolling industry, where profit margins are traditionally low and the cost of widespread use of mainframe computers would be prohibitive.

Computerised production control developments have concentrated on Manufacturing Resources Planning (MRP II) systems. The literature suggests however, that despite the massive investment in hardware, software and management education, successful implementation of such systems in manufacturing industries has proved difficult. This thesis reviews the development of production planning and control systems, in particular, investigates the causes of failures in implementing MRP/MRP II systems in industrial environments and argues that the centralised and top-down planning structure, as well as the routine operational methodology of such systems, is inherently prone to failure. The thesis reviews the control benefits of cellular manufacturing systems but concludes that in more dynamic manufacturing environments, techniques such as Kanban are inappropriate. The basic shortcomings of MRP II systems are highlighted and a new enhanced operational methodology based on distributed planning and control principles is introduced. Distributed Manufacturing Resources Planning (DMRP), was developed as a capacity sensitive production planning and control solution for cellular manufacturing environments. The system utilises cell based, independently operated MRP II systems, integrated into a plant-wide control system through a Local Area Network. The potential benefits of adopting the system in industrial environments is discussed and the results of computer simulation experiments to compare the performance of the DMRP system against the conventional MRP II systems presented. DMRP methodology is shown to offer significant potential advantages which include ease of implementation, cost effectiveness, capacity sensitivity, shorter manufacturing lead times, lower working in progress levels and improved customer service.

This work studied the production of aerosol-phase organic nitrates in both Portland and the Columbia River Gorge (CRG). Ozone and NOx species were investigated for correlation with organic nitrate aerosol, as they function as precursors to the production of organic nitrates. These ambient gas-phase measurements were collected in the same locations as high-volume (Hi-Vol) filters samples, in an urban and rural gorge setting to investigate correlations at the origin of the pollution plume and downwind. A novel Soxhlet extraction method for Hi-Vol filters was developed based on literature and EPA standard methods. Analysis for nitrate production was done by segregating data based on times when the wind blew out of Portland and down the CRG versus times when flow was not westerly. Filters were then compared to ambient gas-phase measurements and derived NO3 radical production rates to look for trends. Wind direction had a strong influence on the concentrations of precursor molecules in the CRG. On days with a westerly wind direction into the gorge, concentrations of the measure aerosol organic nitrates were similar at both sides. This suggests some contribution of a broader regional production of organic nitrates. There was some correlation between the production rate of NO3 radicals and the measured organic nitrate aerosol, suggesting a role for NO3 + VOC production of organic nitrates that later partition to the aerosol phase. This information will better illuminate the fate of nitrogen downwind of pollution sources. The information will also help to create a better understanding of the way topography and meteorological conditions can influence the flow of pollution. Understanding the downwind oxidative chemistry that happens in the CRG would better support both pollution prevention and mitigation efforts.

The overall goal of this work was to investigate microbial activity leading to the anaerobic degradation of polycyclic aromatic hydrocarbons and an organophilic clay sediment cap used at a creosote-contaminated Superfund site. To determine whether or not PAHs were being degraded under anaerobic conditions in situ, groundwater and sediment porewater samples were analyzed for metabolic biomarkers, or metabolites, formed in the anaerobic degradation of naphthalene (a low-molecular weight PAH). In addition, a groundwater push-pull method was developed to evaluate whether the transformation of deuterated naphthalene to a deuterated metabolite could be monitored in situ and if conservative rates of transformation can be defined using this method. Metabolites of anaerobic naphthalene degradation were detected in all samples that also contained significant levels of naphthalene. Anaerobic degradation of naphthalene appears to be widespread in the upland contaminated aquifer, as well as within the adjacent river sediments. A zero-order rate of transformation of naphthalene-D₈ to naphthoic acid-D₇was calculated as 31 nM·d-¹. This study is the first reported use of deuterated naphthalene to provide both conclusive evidence of the in situ production of breakdown metabolites and an in situ rate of transformation. Methane ebullition was observed in areas of the sediment cap footprint associated with organophilic clay that was used a reactive capping material to sequester mobile non-aqueous phase liquid (NAPL) at the site. Anaerobic slurry incubations were constructed using sediment core samples to quantify the contribution of the native sediment and the different layers of capping material (sand and organophilic clay) to the overall methane production. Substrate addition experiments using fresh, unused organophilic clay, as well as measured changes in total carbon in organophilic clay over time supported the hypothesis that microbes can use organophilic clay as a carbon source. Quantitative PCR (qPCR) directed at the mcrA gene enumerated methanogens in field samples and incubations of native sediment and capping materials. Denaturing gradient gel electrophoresis (DGGE) was also performed on DNA extracted from these samples to identify some of the predominant microorganisms within the sediment cap footprint. The organophilic clay incubations produced up to 1500 times more methane than the native sediment and sand cap incubations. The organophilic clay field sample contained the greatest number of methanogens and the native sediment contained the least. However, the native sediment incubations had greater numbers of methanogens compared to their respective field sample and comparable numbers to the organophilic clay incubation. An increase in methane production was observed with the addition of fresh, unused organophilic clay to the already active organophilic clay incubations indicating that organophilic clay stimulates methanogenesis. In addition, organophilic clay retrieved from the field lost about 10% of its total carbon over a 300-day incubation period suggesting that some component of organophilic clay may be converted to methane. DGGE results revealed that some of the predominant groups within the native sediment and sediment cap were Bacteriodetes, Firmicutes, Chloroflexi, and Deltaproteobacteria. An organism 98% similar to Syntrophus sp. was identified in the organophilic clay suggesting this organism may be working in concert with methanogens to convert the organic component of organophilic clay ultimately to methane. The capacity of organophilic clay to sequester organic contaminants will likely change over time as the organic component is removed from the clay. This, in turn, affects the use of this material as a long-term remedial strategy in reduced, contaminated environments.