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This thesis reports on the research undertaken to minimise wastes from overproduction that are created to meet demanding due dates imposed by retailers in convenience food manufacture. The principle objective of this research is to generate knowledge and generic solutions to minimise the environmental impacts of such wastes through effective production planning and improved processing and supply chain practices. The research contribution is divided into three major parts. The first part reviews the most relevant publications and legislation, and categorises the contemporary techniques in supply chain management, operations management and production planning. The second part is concerned with three novel concepts of (a) identifying, modelling and analysing the various types of wastes in food industry (b) the systematic support for the improvement of production and supply chain activities through generation of a Responsive Demand Management framework, and (c) the realisation of a hybrid two stage planning approach for minimisation of overproduction wastes. The final part demonstrates the application of these research concepts through a case study for minimisation of overproduction waste within a ready-meal manufacturer. The hybrid two stage planning approach has been shown to be an effective method by which overproduction wastes can be addressed for products with production lead-times that exceed order lead-times. The responsive demand management framework is a powerful method for the identification and recording of production and supply chain inefficiencies that can be utilised to establish a programme of improvements for further waste reduction. Classification, modelling and analysis of food industry wastes by this research has provided food manufacturing with significant tools to monitor and reduce environmental impacts. The case study has effectively demonstrated the applicability of the research concepts in significantly reducing overproduction waste. In summary, this research has highlighted the environmental and economic impacts of waste and has underpinned the paramount importance of establishing sustainable manufacturing and supply chain procedures in convenience food sectors.

This thesis reports on the research undertaken to analyse the factors affecting end-oflife vehicle value, and to investigate a costing framework to assist the vehicle recovery industry in promoting sustainable vehicle recycling. The principal objective of this research is to develop decision support tools for the vehicle recovery sector to adopt more sustainable processing strategies, whilst meeting the requirements of impending and future legislative targets. The research contributions are divided into three parts. The first part reviews the most relative research in the areas of environmental concerns relating to the automotive sector, end-of-life vehicle recovery and associated costing techniques, to identify the most relevant research directions. The second part consists of a substantial program of data collection, which included; formal interviews, survey of treatment facilities, time-studies and vehicle teardowns, to generate a costing framework for the modelling of indirect and direct costs of both pre and post-fragmentation activities in vehicle recycling. The third part includes the design and implementation of a decision support costing system that enables end-of-life stakeholders to understand the main economics that underpin their operations, and to support future investment in more sustainable vehicle recovery activities. The applicability of the research concept has been demonstrated via three case studies. The results from the case studies have shown that although most end-of-life vehicle recoverers are currently profitable due to the strong demand for scrap metal, significant improvement in their processes and value recovery is possible through strategic investment. Such strategic investment in process improvement and expansion of recycling activities should be considered in light of future fluctuations in material markets and increasing costs of attaining higher recycling targets. In summary, this research has concluded that the realisation of environmentally friendly approaches to vehicle recycling and the long-term survival of the ELV recovery sector is very much dependent on the pro-active and direct involvement of automotive manufacturers in end-of-life vehicle recovery.

Demolition waste materials mainly consist of concrete and bricks and arise from the demolition of existing structures and buildings. Environmental and economical reasons make their recycling necessary but up to date little research has been undertaken to what is perceived as low level reuse of these materials. This project tries to understand the behavioural characteristics of three types of recycled materials to determine their potential for engineering fill applications. For this purpose their physical and mechanical characteristics have been extensively investigated. Two types of crushed concrete, one obtained straight after demolition and the other further processed to industry specifications, and one type of crushed bricks were tested. Due to the variable nature of recycled materials large quantities were tested and their grading, particle shape and aggregate crushing and impact values established. In addition, large scale equipment was developed for the determination of their compaction and permeability characteristics. An extensive large scale shear box test regime was used to determine the shear strength behaviour of the materials. Two different densities and maximum particle sizes were used, and their influence on the shear strength established. The degree of particle breakage was also quantified by sieving the shear box specimens before and after testing. The comparison of the behaviour of the materials during shearing has shown that the two crushed concrete based materials behave similarly despite the different degrees of processing, but there is difference between them and the crushed brick material. The friction angles of the materials decrease with decreasing density and maximum particle size, with the reduction of the latter affecting the friction angles values more. The results show that the friction angles reduce with increasing normal stress, the shear-normal stress envelopes exhibit curvature at low normal stresses and the materials exhibit dilatancy at low normal stresses that decreases with increasing normal stress. This behaviour during shearing is similar to the behaviour exhibited by natural granular materials from literature. For all the three types of materials tested, the friction angles fall above the lower limits of strength for rockfill set by Leps (1970), which indicates their suitability for use as engineered fill.

The UK has adopted a market based approach to the EU Directive on Packaging and Packaging Waste in contrast to other Member States like Germany and the Nordic countries where direct levies on packaging are applied. This research thesis explores the effectiveness of the UK Packaging Regulations in reducing the production and use of packaging by obligated companies, encourages the recycling/recovery of packaging waste, and ensures the introduction of packaging waste management related practices. The environmental impact associated with the mandatory recovery and recycling targets were calculated. Yet the growth in packaging waste is a global phenomenon and in contrast, a review of packaging waste recovery systems in developing countries indicates that an informal sector has contributed immensely towards improving recovery of recyclable materials (including packaging materials) and provides recycling services at low cost to the local community. In contrast to the recovery of packaging waste in developing countries, the key stakeholders in the delivery of the UK Packaging Regulations - the reprocessors and obligated producers of packaging waste in UK were surveyed. Evidence indicates that • household packaging waste has become a vital source of supply to re processors and constitutes 31% of all packaging waste recovered for recycling in 2008. The Packaging Recovery Note income generated by the Regulations has facilitated investment in new recycling infrastructure. The domestic reprocessors in theory have the capacity across all material sectors to take an estimated 1,122ktonnes more packaging waste. The examination of the various material sectors indicates that glass and wood capacity would have sufficient capacity to meet the EU targets while paper, plastics and metals are deficient. This means that the export of packaging waste of paper, plastics and metals will be necessary for UK to meet its EU packaging waste recycling obligations. The cost of packaging waste compliance has raised environmental awareness within \, companies but have not stimulated major changes in business behaviour. There is evidence that the cost of compliance has encouraged some packagifJ,g design changes, improved production process to reduce packaging waste, substitution with other packaging materials and the incorporation of recycled content in packaging products. It has also encouraged discussions with suppliers on scope for reducing packaging, progress in take-back systems for recovery packaging and development of individual approaches by companies obligated under the regulations to develop their own approach to collecting evidence of packaging recovery. As part of the research a recycling and performance waste model, the Packaging and Packaging Waste Carbon Model (PPW-CM) was developed to evaluate the flow of C02eq I I which occur as a consequence of existing packaging recycling targets and possible higher targets which might be introduced through the regulations. The results from the model show that keeping the 2010 baseline recycling targets of 60.7% until 2024 will achieve a net C02eq savings of 8.4 million t C02eq while linearly raising the recycling target to 84.7% (level already achieved across Europe in 2009) by 2024 from 2010 baseline will realise an additional 7.2million t C02eq savings - a significant reduction in global warming potential. The model has shown that recycling packaging waste through the infrastructure set up in the UK can deliver against recycling targets and also offers significant environmental benefits expressed in carbon terms. Developing countries also have the potential to deliver similar benefits, but without formal, organised collection systems, will rely on an informal sector to deliver the necessary recycling.

Solid waste management is a key concern for the local authorities in developing countries. The continued generation of solid waste, increasing waste management costs and scarcity of landfill space have compounded solid waste problems to a serious stage. Local authorities struggling to meet collection targets do not usually think of waste reduction and recycling. Composting is seen as one potential waste reduction strategy through the recycling of waste. As a result, a number of community-based composting projects have been piloted in the cities. Some projects have been successful in producing lasting impacts on the improvement of solid waste management. However, many projects could not support themselves or expand further when the external agencies discontinued their support. This thesis is an attempt to study the state of sustainability and replication potential of four community-based composting operations in Bangladesh.

The closure of anthropogenic substance and material cycles is a central theme in industrial metabolism and ecology. Its desirability is based on the analogy with biological nutrient cycles that are closed, as a requirement for their long-term sustainability. This thesis sets out to assess the level of closure of the UK iron, steel and aluminium cycles; i.e. three of the main structural 'nutrients' of the global industrial ecology. To investigate this a new time-dependent methodology for material flow analysis (MFA) has been developed. In sectors such as iron, steel and aluminium where the life-span of goods may be long and the life-spans differ between applications, it is vital to include a temporal dimension in the MFA; different products available as scrap entered use at quite different past times. In this analysis, residence time distribution theory, as developed in chemical engineering science, has been successfully adapted to simulate the delay of goods in use. The methodology has been applied to track the flows of iron, steel and aluminium through the UK economy. Historic information on the amounts of these metals going into different groups of goods, together with values for their estimated life-spans, have enabled modelling of the yearly release of iron/steel and aluminium scrap from the use phase in the form of end-of-life scrap. The iron and steel MFA carried out in this work shows that for 2001, the estimated release of end-of-life scrap and prompt scrap significantly exceeds the documented amount of scrap that is consumed within the country or is exported. This indicates a loss of end-of-life scrap of around 30% (corresponding to three and a half million tonnes). For aluminium, the analysis also shows that for 2001, the estimated amount of released prompt and end-of-life scrap is higher than the documented amount of recovered scrap. There is a loss of end-of-life scrap of about 20% (corresponding to 160 thousand tonnes). For both metals, a level of closure was achieved in the MFAs; i.e. modelled amounts of metal emerging from use could be largely balanced with documented amounts of metal being recycled and sent to landfill. The analysis shows that using a distribution of the life-span (as opposed to a fixed life-span) when modelling the delay of goods in the use phase is more important when the input of goods into use shows a significant increase or decrease over time. To achieve and maintain higher recycling rates of these metals it is vital to avoid build-up of alloying and contaminating elements in the scrap cycle. A model for exploring potential contamination build-up in the metal cycle has been developed in this work, which builds on the MFA methodology, incorporating the temporal dimension. It examines consequences for the composition of the metal flows depending on different future scenarios. A case study of exploring potential build-up of tin in the iron and steel cycle between 2000 and 2020 was performed to demonstrate the model. Not surprisingly, both increasing recycling rates and decreasing scrap exports leads to increases in the concentration of tin in metal products. By separating the scrap before remelting and choosing more carefully what type of scrap goes to which production, buildup can be avoided. The methodology presented here should prove useful in further exploring potential contamination in metal products and developing strategies how to avoid it. The MFA studies show there are still improvements to be made in recovering end-of-life iron/steel and aluminium scrap. Small products such as packaging stand out as a major challenge for these metals. Therefore, possible ways of collecting beverage cans were investigated in a case study of used aluminium beverage cans (UBCs). Two main issues explored included the questions: (1) Does transport intensity differ greatly between various types of collection systems, recovery rates and population density. and (2) How significant is the environmental impact of the collection stage compared to the whole life cycle of the can. Overall, the differences in environmental impacts between the collection systems (kerbside, can banks and deposit) are not considerable. Transport per collected unit increases with decreasing population density. However, in the context of the whole life-cycle of aluminium cans, the analysis of the systems shows that over a range of population density, the collection stage makes negligible contribution to en- vironmental burdens. The savings in environmental impact of recovering and recycling the cans after use far outweigh the impacts of collecting them. This very much highlights the need for functional and easily accessible recovery infrastructures for aluminium cans in the UK.

Turkey's accession to European Union requires compliance with the EU legislation. Healthcare waste is one waste stream which will be affected by this accession. Currently, in Turkey, especially in large provinces (such as Istanbul) there is an increasing pressure on the government authorities to develop a sustainable approach to healthcare waste management and integrate strategies aiming at pursuing sustainable society. In this respect, the purpose of this research was to develop a framework to support selection and planning of the future healthcare waste treatment systems in Istanbul. In this study, an Istanbul-scale system dynamics model was developed to estimate future healthcare waste generation to 2040 and it was identified whether any of the assumptions made, because of the data gaps, have any significant influence on the outcomes of the model. The study found that more precise data are required on treatment types (acute or chronic), patient episodes (inpatient and outpatient figures in an age spectrum) and waste generation profiles (e.g. anatomic, genotoxic, sharps, etc.) of healthcare institutions. The model also determined a high potential in decreasing healthcare waste amounts (up to. 10,000tpa) through implementing effective segregation along with a significant proportion of the healthcare waste (77%) which being incinerated could, in principle, be treated through alternative technologies. The data generated by the model was used in the context of Multi-Criteria Decision Analysis (MCDA) by identifying various criteria, measuring them and ranking their relative importance from the point of key stakeholders via a questionnaire within four future scenarios. It was found that autoclave/hydroclave technology option for the treatment of healthcare waste suitable for alternative treatment (HCW SAT) and then their disposal through landfilling with energy recovery has potential to be an optimum option and these alternative treatment methods along with an efficient healthcare waste segregation scheme should be given more attention by the authorities in Istanbul. The methodology used in this project has been developed based on the primary aim of the project which is to enable the decision makers in Istanbul to gain an improved perception of the decision problem.