On aggregate, small hotels constitute a significant solid waste management (SWM) problem undertaking landfill as a main waste disposal strategy for hotel waste. This not only adds to the degradation of the environment but also imposes a significant cost over the business in terms of production and disposal of the waste. However, analysis of the literature revealed that the issue of SWM in the context of the small hotel sector had been paid little attention by academics. This research intends specifically to identify the challenges of adopting sustainable SWM practices in small hotels and provide potential solutions. A conceptual framework was evolved to guide this study. It merges Theory of Planned Behaviour (TPB) with SWM best practices to understand hoteliers’ attitudes and the obstacles of implementing sustainable SWM options. A phenomenological perspective was adopted to investigate SWM issues in two different case studies of small hotels in Wales using: semi-structured interviews, direct observation and document analysis. First, a case study of non-Green Dragon Environmental Standard (GDES) small hotels in a Welsh local authority was developed. The findings revealed that most non-GDES hoteliers highly prioritized landfill and felt negatively about the implementation of sustainable SWM options with the exception of recycling. There is also a perceived range of behavioural constraints, among these: lack of awareness; lack of recycling and composting facilities; poor manufacturers’ production and packaging strategies; lack of space, time and cost issues. A part of this case study, the potential role of public and private waste sectors was examined through undertaking semi-structured interviews with the executive of both sectors. The results identified limitations of SWM operations undertaken by both sectors. Second, a case study of small hotels committed to GDES in Wales was designed. Most GDES hoteliers held positive attitudes and implemented sustainable SWM options. In comparison, non-GDES hoteliers had no intention of managing their solid waste effectively, even after the recycling service was made available to them by the local authority – an issue which necessitates government intervention. A cross-case analysis was undertaken identifying seven means of motivations to influence hoteliers’ behavioural intentions in relation to SWM: providing recycling and composting facilities; providing awareness and education; enhancing the economic motivation; encouraging the social motivation; boosting the marketing motivation; enacting legislative pressure; building networks between small hotels. A major contribution of this study is related to the development of a best practice model for the public sector to encourage better SWM practices in small hotels, along with an input/output process model to support/oblige public and private waste sectors to apply sustainable SWM practices and work more closely with small hotels. Also, the study had verified that the model of TPB with its main components (Attitude, Subjective Norm and Perceived Behavioural Control (PBC)) was not adequate to explain the attitude/behaviour relationship.

This research examines the sustainable waste management in Malaysia \\lth using current recycling program in Kota Kinabalu. Sabab, Malaysia·as a case study. With using infonnation's from questionnaire, interviews, and Life Cycle Assessment (LeA), the study examines a range of recycling issues focusing on public intention and behaviour, the contribution of the fonnal and informal sectors and the environmental consequences of waste management Utilising several methods public survey, interviews and LeA - the data were analysed for possl'bilities for expansion of recycling in the future. The results of this study show that there are promising indications ofparticipation from the private and informal sector which may increase the perfonnance of the program in future. To induce public involvement requires an effort by government, and could have a considerable effect on the future . establishment ofrecycling as the main method ofovercoming the waste management problem in the country. In addition, a waste management options analysis showed that there is great potential for reducing the environmental consequences of recycling waste. This study highlights several important issues: first:, there is a need to educate the public on the importance of recycling and to provide basic faCIlities for this in housing areas. Second, the government recycling program needs to include the infonnal collection syst~ as the latter contnoutes significantly to the overnll perfonnance of the program. Third, the government needs to understand the environmental consequences of waste management practise (results from LCA) to maximise the perfonnance of the service ill the area. Fourth, a reprocessing plant should be established in the area which can process waste material locally rather then transporting it to the mainland, thus reducing management costs and environmental damage.

Strontium-90 is present in contaminated land at nuclear sites around the world and is also an important component of nuclear waste inventories. The mobility of 90Sr in the subsurface is often controlled either by adsorption to sediment particle surfaces or incorporation reactions into secondary mineral precipitates. This thesis presents the results of a multidisciplinary study examining the behaviour of 90Sr in West Cumbrian unconsolidated aquifer sediments under a range of groundwater and anthropogenic liquor compositions relevant to contaminated land scenarios. Experiments using low ionic strength (IS) regional .groundwater at circumneutral pH found 90Sr was almost completely removed from solution. In higher IS artificial waste tank leachate (PH 11), sorption of 90Sr decreased, suggesting that higher concentration of ions in solution inhibited 90Sr sorption. In both scenarios, EXAFS data confirmed that Sr was present as an outer-sphere adsorption complex. Sorbed 90Sr remained exchangeable with MgCl2 even after one year. In contrast, experiments using pH 13.5 young cement water (YCW), found very high sorption despite the extremely high IS. EXAFS analysis of samples suggested that mineral alteration and the formation of secondary phases had occurred. Secondary phases initially sorbed Sr via inner-sphere adsorption, but in a sample aged for a year at 70 [degree]C there was evidence of Sr incorporation in a newly formed zeolite mineral which was identified as K-chabazite. Once incorporated, Sr was only desorbed using a pH 1.5 solution. Finally, experiments using Ca(OH)2 (PH 12.7) found no evidence of mineral alteration, and sorption was inhibited by the higher ionic strength present.

This thesis was an exploration into the implementation process in developing country cities. Western debates on implementation are usually not applicable in developing country cities and the question asked was why. The main reason has been found is that the characteristics of governments and people in developing country cities are different and therefore different approaches are required to make implementation successful. Of particular interest is waste management. Different approaches are employed in the management of waste in some developing country cities and the results have been mediocre with no real impact on the urban environment. To this end, this thesis set out to understand implementation within these cities. In the course of this research, some very interesting factors were discovered about policy implementation in developing country cites. It is hoped that this thesis has been able to add to the body of knowledge in understanding implementation in developing country cities.

The chemical erosion of bentonite buffer material, during periods of glaciation, is a point of concern in the approval of safety cases for disposal of radioactive waste in crystalline rock. Currently, quantitative mass loss assessments are based on a 100% montmorillonite buffer and lead to unacceptable mass loss predictions. In practice however, the buffer will be comprised of ≈80% montmorillonite and ≈20% accessory minerals. A better understanding therefore of the role accessory minerals play in the erosion process is required to inform more realistic mass loss assessments. As indeed is the presence of fracture aperture variability on the extrusion/erosion process, as almost exclusively, research carried out to date has been in uniform aperture fracture flow cells. Four month duration erosion experiments were undertaken, designed to mimic groundwater flow through, and buffer extrusion/erosion into, a fracture intersecting a deposition hole in the KBS-3V disposal concept upon contact with dilute water. Purified montmorillonite in a planar aperture fracture was examined, as was the reference bentonite buffer material for the KBS-3V concept, MX80 (with accessory minerals), in both planar and naturally variable aperture fractures. In line with work by other researchers, the purified montmorillonite exhibited a steady mass loss throughout the experiment, with no mechanism in place to attenuate mass loss. Data correlated for the experiments with MX80 to reveal an erosion mechanism in which the accessory minerals serve to inhibit erosion when deposited at the extrusion/groundwater interface at a critical thickness. Irrespective of whether a variable or planar aperture fracture was used. Aperture variability plays a role in that, after deposition of the minerals at a critical thickness and subsequent decrease in mass loss from the system, force chain development in the accessory minerals against the variable aperture wall facilitated a rise in swelling pressure, resulting in breach of the accessory mineral barrier. An erosive period ensues, during which the breach is healed and the barrier regains its integrity. Simplified assessments, scaling the experiments to a repository scenario by incorporating the mitigating effect of the presence of accessory minerals into current quantitative mass loss assessments, predict mass loss over the course of a repository assessment period to be within acceptable limits.

A novel process for recovery of niobium, vanadium and scandium from TiO2 residues in three stages consisting of acid leaching, selective precipitation and oxidative alkali leaching has been developed using a batch leach test rig. While technologies for recovering these valuable metals from various minerals as co-products or by-products are commercially available, they are not currently used for recovering them in combination. An integrated process for reclamation of the metals could increase the total values recovered while reducing the objectives to their subsequent disposal. Three batches of TiO2 filter cake were obtained from Huntsman Pigments and Additives between 2012 and 2014, and were analysed using ICP-OES, TGA, XRD, SEM-EDX and XRF. The samples contained different amounts of unreacted ore and coke, together with hydrated oxides of a wide spectrum of metals such as vanadium, scandium, iron and niobium. Initially, Pourbaix diagrams were utilised for mapping out when the metals would precipitate or be in solution depending on their concentration, solution pH and electrochemical potential. The information was compared with established metal recovery processes to determine the recovery route. This study showed that the metals could be separated by selectively precipitating and filtering niobium from acidic media at pH ≈ 1 followed by controlled co-precipitation of vanadium and iron at pH ≈ 2 and scandium at pH ≈ 4. It was also determined that further concentration enhancement could be achieved by oxidative alkali leaching after the selective precipitation steps. Following establishment of the metal recovery route, experiments were carried out to sequentially study the effects of temperature, lixiviant concentration, reaction time, pH, stirring speed, solid-liquid ratio and oxidant concentration on dissolution and precipitation of the metals. The chloride process of TiO2 production is operated under reducing conditions therefore most hydroxides in the filter cake are in a reduced state. NaNO3 was used as an oxidant for improving metal recovery and selectivity during Na2CO3 leaching. Vanadium purification by salt roasting was investigated and the conventional NH4VO3 precipitation route was utilised for vanadium precipitation from pregnant solutions. Recoveries of over 80 % were achieved for vanadium and niobium, with grades of 99.5 % and 16 % respectively. Zirconium, titanium and thorium were the key impurities in the niobium-rich precipitates. Nearly all the scandium was recovered with a grade of at least 50 % in an alkali solution where rare earths were the main impurities. Adding NaNO3 to the alkali leaching systems significantly improved the extraction of vanadium and scandium, while niobium’s selective precipitation at pH 1 was catalysed by sulphate ions. The random pore model governs the dissolution processes, with all acid leaching kinetics being controlled by pore diffusion and alkali by surface reaction. The developed process opens up opportunities for recovery of other metals, particularly titanium, iron and REE and can be employed for recovery of the metals from filter cake already landfilled.

The African urban marketplace environment (MPE) is a space with deep cultural significance forming a focal point of economic and social life in African societies. Every African irrespective of their social status has contact with the marketplace. It is an influential, complex and highly dynamic space that deserves to be effectively managed. However, one significant challenge faced in the management of African marketplaces is how best to manage solid waste in order to provide a safe and clean environment. There is evidence in literature that inadequate solid waste management (SWM) in MPE is related to the attitudes of the market users, which has been incessantly tagged as ‘poor’. Literature also indicates a lack of sufficient understanding of the MPE and the factors that underpin the users’ attitude towards waste. Therefore, the aim of this study is to provide an in-depth understanding of the dynamics of the MPE in order to identify the key underlying factors that underpin the attitude of market users towards waste. The research is undertaken in the Facilities Management (FM) context. It focuses on the environmental management component of FM with a particular consideration to SWM as a key reoccurring FM theme in the MPE. Primary data generation and collection was undertaken within the City of Port Harcourt, Nigeria. Adopting a sequential mixed model research design, four markets were selected and data generated using non-participant observation, semi-structured interviews, questionnaires and focus group research instruments. Non-participant observation of the four markets was carried out, 43 semi-structured interviews were conducted, and 746 questionnaires were administered. Finally, a focus group session made of 10 market stakeholders across the cases was conducted. The research established 10 key factors that could enhance the SWM practices in MPE. Through the application of analytical tools - Relative Importance Index (RII) and Interpretive Structural Modelling (ISM) - the relative importance and the interdependencies between the factors were evaluated respectively. An ISM Influence-based Model was developed to serve as a guide for better SWM practices in MPE. The study also identified five key factors that underpin the attitudes of the market users towards waste. Contrary to existing literature, the research established that the trigger and facilitation of desired attitudinal change lies primarily with the market managers rather than the users. These outcomes of the research provide the essential knowledge to market facilities managers particularly in aiding to improve performance in environmental management as a core component of FM services in MPEs. It can be concluded that this research will enhance the effective functioning of markets by providing a safe and clean environment, which will have an impact on the attitude of the community towards waste.

It has been recognised that the informal E-waste recycling may pose a risk to human health and the environment, this study aims to evaluate the e-waste contamination and the environmental and human health impact of informal e-waste recycling on the exposed population using the risk assessment framework. The distribution of a number of heavy metals in soil from an informal recycling site in the largest market for used and new electronics and electrical equipment in West Africa was investigated. The extent of pollution, potential bioavailability of heavy metals, potential risk due to the recycling activities and impact of external factors such as rainfall were assessed. In recent times, bioaccessibility has emerged as a testing tool used to accurately estimate the risk posed on human health by exposure to environmental contaminants, the oral bioaccessibility and inhalation bioaccessibility was also assessed. The concentrations of all the identified metals in the recycling site were consistently higher than values obtained from the control site, suggesting the impact of the recycling activities on the soil. The order of total metal concentration was Cu > Pb > Zn > Mn > Ni > Sb > Cr > Cd for both the dry and wet season. The total concentration of Cd, Cu, Mn, Ni and Zn where was significantly higher (p≤0.001) in the dry season than in the wet season. The concentrations of Cu (329-7106 mg kg-1), Pb (115-9623 mg kg-1) and Zn (508-8178 mg kg-1) were consistently higher than the international soil guideline values. Using a sequential extraction method, the potential bioavailability of the metals was indicated as Cd > Sb > Zn > Cu > Ni > Pb > Cr, suggesting Cd was the most potentially available. Assessing the risk using the Potential Ecological Risk Index (PERI), Cu was found to contribute the most to the potential ecological risk and Cd the greatest concern due to its high toxic-response factor within the study site and the Risk Assessment Code (RAC) suggested Cd posed the most risk in this site. Furthermore, the oral bioaccessibility test showed that less than 40% of the total concentration of all the identified metals was potentially available for absorption in the gastrointestinal tract. In the inhalation bioaccessiblity, with the exception of Cd, the percentage bioaccessibility of the other metals was less than 35% after 120 hours. The health risk characterization indicated the adverse human health effect through the ingestion pathway and a relative lower probability of risk through the inhalation of pathway. This study established a high level of contamination as a result of the informal recycling activities, underscores the importance of applying speciation and bioaccessibility and bioavailability in risk assessment. Finally, in an attempt to evaluate the risk, the study proposed an integrated risk assessment framework which when tried and tested is aimed to positively influence the risk judgement and ultimately risk management decisions whereby providing valuable insights that would translate to an efficient and sustainable management system at the long run.

No description available.

Thermal processing is an effective technique for recycling waste plastics in a sustainable way. The pyrolysis of waste plastics, followed by reforming reactions of the pyrolysis products generates syngas (hydrogen and carbon monoxide) that has a vast array of applications. To date, the steam reforming process has been the most researched technology for syngas production from waste plastics. However, this process produces a large amount of carbon dioxide. Due to the concern related to global warming associated with the emissions of carbon dioxide into the atmosphere, the recycling of carbon dioxide through the pyrolysis-reforming of waste plastic, (dry reforming) is environmentally attractive. The dry reforming process was the focus of this research. A preliminary thermogravimetric and kinetic analysis was conducted in order to have a general understanding on the effect of CO2 in a waste plastics pyrolysis. The results show that most plastics required lower activation energy with the presence of CO2 in the pyrolysis atmosphere (N2:CO2 ratio of 7:3). A two-stage pyrolysis-catalytic dry reforming reactor was used to investigate various process conditions and types of catalyst to maximise syngas production. The two-stage fixed bed reaction systems increased the H2 in both a N2 or CO2 atmosphere. Ni/Al2O3 based catalysts with different metal promoters (Mg, Cu and Co) were selected for the investigation of pyrolysis-dry reforming of waste plastics. Among the catalysts tested, the Ni-Co/Al2O3 catalyst presented the highest catalyst activity resulting in a syngas production of 149.42 mmolsygas g-1plastic with 58% carbon dioxide conversion, also no detectable carbon formation on the catalyst surface was observed. The dry reforming reaction was also favoured with the Ni-Co/Al2O3 catalyst with high cobalt content. Various process parameters such as catalyst preparation method, reforming temperature, CO2 feed input rate and catalyst to plastic ratio were tested. It was found that the addition of steam in the catalytic-dry reforming process manipulated the H2/CO molar ratio, based on the type of catalyst used and the CO2/steam feed ratio. Better catalyst activity in relation to H2 production was observed for the Ni-Mg/Al2O3 catalyst and Ni-Co/Al2O3 catalyst favoured CO production. Different types of plastics; individual and mixed plastics from different waste treatment plants were also processed through the catalytic-dry reforming process to determine the syngas production and catalyst activity of Ni-Co/Al2O3 catalyst. This research has suggested that the use of carbon dioxide as the reforming agent in the dry reforming process of waste plastics was comparable to the current reforming technology with an optimum syngas production of 148.6 mmol g-1SWP.