Since the usage of chemical flocculants especially polyacrylamides is closely related with environmental pollution and health hazards, synthesis of environmental friendly and economic viable bio-flocculants that exhibit high flocculating efficiency is highly desirable. The production of natural bio-flocculants extracted from plant is urgently needed as an alternative to chemical flocculants due to their inherent low toxicity, biodegradability and low environmental footprint. In this study, a plant-based bio-flocculant was extracted from Hibiscus/Abelmoschus esculentus (okra) with conventional hydrothermal extraction (CHE) and microwave assisted extraction (MAE) processes by using water as solvent. The aims of this work were to produce the bio-flocculant through environmentally friendly and economically feasible process, optimise its extraction yield, optimise its flocculating and sludge dewatering properties, and also minimise its production cost in order to be comparable to chemical flocculants (polyacrylamides) from perspectives of quality and cost. The extraction efficiencies of bio-flocculants were justified by the optimised yields, the flocculating abilities were evaluated by the removal of suspended solids (SS) and turbidity after flocculation process and sludge volume index (SVI) whereas the sludge dewatering abilities were assessed by SS removal after filtration and water recovery. Single factor experimental design was employed to study the effects of extraction temperature, time, solvent loading, and agitation speed and particle size on yield, flocculating and dewatering properties of bio-flocculants. The influence of extraction parameters to yield and the reliability of the experimental data were verified by analysing the single factor experimental results with response surface methodology. Results showed that extraction yields were significantly affected by extraction temperature and time and solvent loading. Prolonged extraction (few hours) at high temperature (60-90 ˚C) decreased the yields of bio-flocculants extracted with CHE method. Conversely, extraction at high temperature was favourable for MAE method to raise the yield due to short extraction time in minutes. Flocculating abilities of bio-flocculants were not significantly affected by the extraction conditions whilst the sludge dewatering abilities were mainly influenced by the temperature and particle size. High extraction temperature at ≥ 70 ˚C and the smallest okra particle size at 1mm were the crucial conditions for extraction of bio-flocculants with high dewatering abilities which showed > 95% of SS removal after filtration and ≥75% of water recovery. The optimised yield of CHE at 25.9% was obtained at 50 ˚C, 2 hours, solvent loading of 2.5 w/w and agitation at 200 rpm. On the other hand, microwave-extracted bio-flocculants were best extracted at 90 ˚C, 10 minutes, and solvent loading of 3.5 w/w and okra particle size at 1mm to get the optimised yield at 48.7%. These results revealed that the extraction yield has been enhanced by 87.8% by using MAE method and the extraction time was markedly reduced from hours to minutes. This study uses a combination of empirical observations and an analysis of mass transfer behaviour to yield new insights into the mechanism of MAE. Enhancements in extraction rate and yield achieved by microwave extraction were observed experimentally compared with hydrothermal extraction at temperatures in excess of 50 ˚C, however at lower temperatures there was no observable difference between the two processes. A step-change in extraction yield between microwave and hydrothermal processes was shown to be caused by selective heating. A temperature gradient of the order of 1 ˚C is sufficient to reduce the water chemical potential within the plant cell structure, which causes diffusion of water solvent into plant cell such that internal plant cell pressures can increase to the point where disruption occurs. These findings demonstrate the need to operate microwave extraction processes at a temperature that enables selective heating, and a newly-proposed mass transfer phenomenon that could have wider positive implications for extraction and leaching processes. The bio-flocculants extracted with both methods were applied in flocculation and sludge dewatering without pH alteration and addition of coagulant. Efficient flocculating abilities were attained with >99% of SS and turbidity removal and < 10 mg/L of SVI. However, microwave extracted bio-flocculants were shown to exhibit higher dewatering abilities than hydrothermal extracted bio-flocculants. The bio-flocculants displayed the results of >95% SS removal after filtration and 75% water recovery during sludge dewatering at dosage of 30 mg/L, and was shown to be comparable to or even better than polyacrylamides due to achievement of higher water recovery at the same dosage. Dried bio-flocculants were found to have higher dewatering abilities than aqueous bio-flocculants, probably because drying at low temperature (40 ˚C) has minimised the moisture content and extended the shelf life of bio-flocculants. Biopolymer bridging was preliminary predicted as the plausible bio-flocculation mechanism. The economic feasibility of production of industrial scale bio-flocculant was investigated and the production process was modelled by using SuperPro Designer v9.0 simulation software. The MAE process in continuous mode was verified to be more economically viable than CHE process either in batch or continuous mode if the production scale was beyond 15 tonne/year. Sensitivity analysis for continuous microwave process was conducted and the results indicated the strong influences of annual production and extraction yield followed by raw material okra price on the unit production cost. Continuous microwave process with extraction conditions at 90 ˚C, 10 minutes and solvent loading of 3.5 w/w was identified as the optimised scheme for production of industrial scale bio-flocculant at the lowest production cost. The estimated selling price of aqueous and dried bio-flocculants for an annual production of 220 tonne/year were 41 and 52 $/kg respectively, and was shown to be lower than food grade bio-flocculants but higher than polyacrylamides. This work has clearly showed that okra bio-flocculant could offer a feasible and sustainable alternative to synthetic flocculants for water treatment and sludge dewatering applications due to its high efficiency in flocculating and dewatering, and can be extracted using only water as a solvent, minimising the environmental footprint of the extraction process.

This study focused on the long-term cycling of radiocaesium in pine forests at Boundary Plantation (Sherwood Forest, England), Chernobyl (Ukraine) and Wat Ban Chan in northern Thailand, each of which received markedly different levels of contamination due to radiocaesium deposition from the atmosphere under different circumstances. Systematic studies were made of stable and radiocaesium, potassium and rubidium in soil horizons, tree stems, needles and throughfall (the latter only at Boundary Plantation). Measurements of total concentrations were complemented with determinations of exchangeable fractions as well as the isotopic exchangeability of radio- and stable caesium. Data from Boundary Plantation and Wat Ban Chan were used to test, validate and calibrate the RIFE (Radionuclides in Forest Ecosystems) model for long-term forecasts of radiocaesium behaviour in forest ecosystems. Finally, modelling of 137Cs migration in forest soils was carried out to describe the relationship between the depth of the forest soil profile and the year of litterfall, to better understand the migration of fallout 137Cs. Boundary Plantation, a forest of semi-natural Corsican pine (Pinus nigra), receives chronic atmospheric fallout from nuclear weapons tests in the 1960s. Forest samples were collected every three months from June 2014 to March 2015 at a 24 randomly located sampling sites. The forest soil has a well-developed surface organic horizon while the mineral soil is composed almost entirely of quartz with no identifiable clay minerals. About 65% of nuclear-weapons fallout 137Cs is distributed within the organic layer (upper 9 cm) and maximum of vertical distribution is 12.9% at 8 cm depth. The accumulation of well-decomposed organic matter in the middle of the organic layer is strongly related to the migration of 137Cs in the soil; modelling describes the relationship between the depth of organic matter accumulating in the upper part of the forest soil profile and the year of litterfall indicates that fallout 137Cs deposited in 1963 has migrated in tandem with organic matter at the same rate of migration from the surface. Soil pH also appears to play a key role in controlling the mobility of Cs isotopes, with the most acidic layers within the soil organic horizons holding the highest 137Cs activity concentrations and having the highest exchangeable 133Cs concentrations. Wat Ban Chan in Thailand is a native tropical forest of Pinus kesiya (or Three-needled pine) which received chronic distribution of atmospheric fallout from nuclear weapons tests in the 1960s. Samples were taken from this site in late February 2016 at six randomly located co-ordinates. The forest soil is typical of similar forest soils in the tropical zone. The organic matter, even at the surface, is much less abundant than in temperate forest soils while the mineral soil is composed almost entirely of quartz with no identifiable clay minerals. About 84% of nuclear weapons fallout 137Cs is distributed within the upper 3 cm and the maximal distribution is 37.6% at 2 cm depth. Even though the organic matter content in the upper 2 – 3 cm of the soil profile is low it probably still plays an important role in the vertical distribution of 137Cs. The variation of soil pH throughout the upper 13 cm of the soil profile is less than 1 pH unit and thus is unlikely to influence the vertical distributions of 137Cs and 133Cs in the soil. K and Rb are strong competitors of Cs during cycling within the forest ecosystems at Boundary Plantation and Wat Ban Chan. K is present in the exchangeable fraction in soil at much higher concentration than Rb and especially Cs. The overall degree of translocation from soil to needles is in the order of 39K > 85Rb > 133Cs. Forest sites surrounding the Chernobyl nuclear power plant in Ukraine received acute and localised deposition of nuclear fallout during the Chernobyl reactor accident in April and May 1986. Samples were taken from four Scots pine (Pinus sylvestris L.) plantations close to Chernobyl in early September 2015. Tree cores were taken at all four sites (Red Forest, North Trace, Kopachi and Bourakovka). Soil cores were also collected at Kopachi where 137Cs behaviour appears similar to 133Cs as indicated by Tag values of 133Cs and 137Cs. Scots pine at the Red Forest and the North Trace sites were exposed to extremely high and acute radiation doses (more than 5.0 mGy/h) in the very early stages of the Chernobyl accident. The surviving Scots pine trees sampled in 2015 show a transient decrease in growth rate for several years after 1986, and then show signs of accelerated growth possibly due to a reduction in competition from surrounding trees (an effect known to foresters as ‘growth release’). Calculations of present day 137Cs distributions using the RIFE model for Boundary Plantation and Wat Ban Chan calibrated with inter-compartmental half-times from seven European (‘SEMINAT’) forest sites proved surprisingly accurate, although the model consistently under- and over-predicted the percentage of the total 137Cs inventories retained in the organic and mineral soil layers, respectively. Site-specific calibrations of the RIFE model were made using newly acquired data for nuclear weapons 137Cs deposited in 1963 at Boundary Plantation and Wat Ban Chan. It is considered that these calibrations are more applicable for long-term predictions of radiocaesium cycling in forests than the SEMINAT calibrations which were based on measurements made less than 10 years after the Chernobyl accident in 1986. Finally, measured unsupported 210Pb activities in forest soil profiles were modelled to describe the relationship between the accumulating depth of organic matter in the forest soil profile and the year of litterfall, to improve understanding of the migration of fallout 137Cs at Boundary Plantation (Sherwood Forest, UK) and in the relatively organic-poor soil at Wat Ban Chan in Thailand.

Conventional dust dispersion models which employ Gaussian concentration distributions are routinely applied to predict the dispersion and deposition of fugitive dust arising from quarrying activity. However, these models are known to over-predict the long range transport of particulates beyond the confines of the quarry pit, because their complex terrain algorithms are unable to accommodate the steep gradients which are typically encountered in quarry excavations. They therefore cannot account for the internal flow regimes which contribute to the removal of suspended particulates from the air stream. Consequently, a need arises within the extractive industries, for improved dust dispersion models that are not constrained by quarry topography. This research project attempts to address this deficiency in the modelling of dust emissions from quarry blast events, by presenting an optimized RANS k−ε approach which can adequately simulate the flow-field in which particulates are entrained under a range of meteorological conditions. The stages involved in the incremental development of the numerical model are documented in the thesis, and commence with characterization of the atmospheric boundary layer. In particular, the Monin-Obukhuv Similarity Theory is applied to parametrize the atmospheric surface layer, which exerts the most influence on the dispersion and deposition of near-ground particulate emissions. Modifications to the standard k − ε model coefficients and the inclusion of buoyancy source terms have been adopted in this work, in accordance with previous studies by Alinot and Masson (2005). These modifications ensure that the turbulence closure equations are compatible with Monin-Obukhuv Similarity scaling of the atmospheric surface layer. The Businger-Dyer flux profile functions have been employed to introduce stability modifications to the logarithmic velocity, temperature and turbulence profiles which have been defined at the inlet boundaries of the computational domain to enable numerical representation of both adiabatic and diabatic atmospheric conditions. Furthermore, the Lagrangian Discrete Phase Model has been coupled with Eulerian solution of the flow field to provide a robust means of replicating fugitive dust dispersion through the stochastic tracking of injected particulates. The project also presents a consolidated post-processing methodology to incorporate wind direction variability due to mesoscale atmospheric effects into the CFD model. This methodology use the Moore (1976) equation to parametrize the standard deviation of wind direction variability and proposes a novel, Gaussian probability weighted averaging procedure to arrive at a resultant plume which accounts for the influence of mesoscale wind variability on particulate trajectory and improves the k −ε predictions of lateral spreading of the dust plume. Simulations of flow and dispersion over a series of idealized cosine depressions of varying aspect ratio have been used to assess model predictions of the flow regime and the corresponding plume attenuation within artificial valleys. To allow the model to accommodate negative terrain elevations and to produce profiles of the flow variables which conform to wall topography, a wall-distance scalar has been introduced to ensure consistency of the inlet profile with the flow solution within the domain. These simulations have demonstrated that the proposed model surpasses UK-ADMS in terms of its ability to resolve strong recirculation regimes in deep depressions. The project culminates in a case study of the Old Moor Quarry in Buxton, Derbyshire. This case study tests the viability of the proposed k−ε model and validates the model predictions of dust dispersion with field measurements obtained over the course of a monitoring campaign of approximately one month duration. Meteorological pre-processing steps in accordance with the findings of Holtslag and Van Ulden (1983) have been employed to derive atmospheric surface layer input parameters from routine meteorological data measured at the quarry site, eliminating the need for sophisticated meteorological measurements. Dust dispersion predictions obtained using the conventional dust dispersion model UK-ADMS, have been compared to the CFD model results to demonstrate the improved prediction accuracy of the proposed k −ε approach. Notably, the CFD model is shown to account for the various flow regimes which arise due to the combined effects of the site meteorology and the complex terrain of the quarry excavation. Importantly, the statistical Performance metrics, FAC2, MG, FB and NMSE recommended by Hanna et al. (2004) for the evaluation of dispersion model performance, have been used to assess the accuracy of fugitive dust deposition predictions obtained from the proposed model. The performance evaluation exercise indicates that the buoyancy modified k − ε model outperforms UK-ADMS for all of the metric tests. The incorporation of the wind variability weighted averaging procedure in the case study simulations is seen to reduce uncertainty due to random error, quantified by NMSE. This due to the fact that the wind variability averaging procedure evens out outlying predictions which may be due to the inherent stochasticity of the DPM model.

With the rapid growth of the penetration of wind power into the power system, fixed series compensation is considered as an economic solution to increase power transfer capability. This will render the power system vulnerable to Sub-Synchronous Resonance (SSR). This thesis conducts research on the effect of wind turbines represented by Fixed Speed Induction Generator-Based Wind Turbines (FSIG-WTs) and Fully Rated Converter-Based Wind Turbines (FRC-WTs) on damping SSR. Firstly, SSR is investigated through mathematically modelling IEEE First Benchmark Model (FBM) using MATLAB package. Modal analysis is used to study SSR over a wide range of series compensation percentages. Secondly, the effect of incorporating FSIG-WTs into FBM on SSR is studied over a wide range of series compensation percentage and different power size of FSIG-WTs. Furthermore, the ability of the grid-side converters of the FRC-WTs connected with the FBM to damp SSR occurrence in the steam turbine shafts is evaluated using two different types of control. An optimal controller based on a Linear Quadratic regulator (LQR) has been designed as an auxiliary controller of the grid-side converter of FRC-WTs. A full-order observer was designed to estimate the unmeasured state variables to enable a vii full-state feedback. Finally, eigenvalue sensitivity was studied to choose the most suitable feedback signal for an SSR damping controller. Lead/Lag compensation controller based on the residue method is designed as an auxiliary controller within the grid-side converters of FRC-WTs. Eigenvalue analysis and time domain simulations over widely varying levels of series compensation have been carried out. The simulation studies were carried out in MATLAB and PSCAD. Connecting FSIG-WTs to the FBM increases the range of series compensation level at which SSR can occur. Therefore, it was shown that FSIG-WTs have an adverse effect on the SSR occurring at the multi-mass synchronous generator. If the system is visible, LQR as an auxiliary damping controller within the grid-side converters of FRC-WTs is an effective controller to damp SSR over a wide range of series compensation percentages. Based on eigenvalue sensitivity technique, synchronous generator speed deviation is the most suitable feedback signal for damping SSR occurrence in the steam turbine shafts.

The field of nanotechnology is growing vastly, both as a field of research and in commercial applications. This rapid growth calls for synthesis methods which can produce high quality nanomaterials, while being scalable. This thesis describes an investigation into the use of a continuous hydrothermal reactor for the synthesis of nanomaterials, with potential use in three different biomedical applications – bone scaffolds, fluorescent biomarkers, and MRI contrast agents. The first chapter of this thesis provides an overview of nanotechnology: the advantages of nanoscale, the commercial industries which can benefit, and the predominant methods currently used to produce nanomaterials. Some advantages and drawbacks of each synthesis route are given, concluding with a description of the Nozzle reactor – the patented technology used for nanomaterial synthesis in this Thesis. Chapter 2 then focusses on the characterisation techniques used in this thesis, detailing the principles of how data is obtained, as well as highlighting the limitations of each method. With the background information in place, chapters 3, 4 and 5 describe more specific nanomaterials and how they can be applied to each of the aforementioned biomedical fields. These chapters provide the technical details of how various nanomaterials can be synthesised using the Nozzle reactor, and the structural data (crystallinity, particle size) obtained from these samples. Furthermore, the functional properties of these nanomaterials are tested and the results, along with a discussion of any trends, are presented. Finally, this thesis concludes with a summary of the results described and emphasises the key areas where further work can be conducted.

In this EngD project I developed a new, analytic equation of state for use in the area of CCS pipeline transport. It was my aim to design a model which would exhibit a high degree of accuracy within the anticipated window of operation of CCS pipelines; from 260 to 335K and 1 to 200bar, whilst simultaneously retaining a simplicity and ease-of-use, a lack of which made some other available equations particularly unwieldy. Having conducted a comprehensive literature review and attended many academic and industrial conferences throughout this project, I felt that there was a need for an equation of state which could perform both these functions. This was the key motivation for my work, and the model presented in this thesis was developed in order that it might contribute towards negating the many concerns that currently surround the pipeline transport stage of CCS. I aimed for the proposed model to display a complexity approaching that of some of the simpler equations currently available, whilst incorporating sucient flexibility to give thermodynamic predictions to a standard approaching that of those which are more complicated. I defined criteria by which the proposed model could be judged, so that it could be applied with condence in the determination of the physical properties of carbon dioxide mixtures during CCS pipeline transport. Work was carried out by fitting the parameters of the proposed model to experimental data gathered from the literature, so that it would be able to determine the homogeneous phase pressure and vapour-liquid equilibrium behaviour of carbon dioxide and other relevant gas mixtures. The project yielded a number of excellent outputs, not least the satisfaction of the primary aim which was the proposal of a model, which through this EngD, I demonstrated had the ability to meet the demands that were set. In carrying out this work, I also developed several highly useful auxiliary mathematical methods which helped in ensuring the proposed model was as accurate as possible. For the case of modelling pure carbon dioxide, the proposed equation worked exceptionally well, providing highly accurate predictions for homogeneous density and vapour liquid equilibrium, which were well within the targets set. A paper on this was published in May 2013. In extending the model to incorporate some binary mixtures I again found that it demonstrated a clear ability to capture the necessary physical behaviours within the target range. I concluded with suggestions as to ways in which the work presented here could be developed further, as well as the many avenues for future work in other areas that this EngD project had opened up.

The continuing need for improved assessment of risk from heavy metal contamination of the environment has prompted scientific interest in quantifying and predicting metal solubility, ‘lability’ and bioavailability. This has led to the development of new techniques to fractionate and speciate trace metals in soils. The objectives of the current study were to increase understanding of the effects of (i) soil properties, (ii) contaminant source and (iii) contact time on metal lability and solubility in soils. Multi-stable isotope dilution (ID) methods were used to determine the lability (E-values) of Ni, Cu, Zn, Cd and Pb in soils, alongside more traditional approaches employed for metal fractionation including single and sequential extraction procedures. Most of the work was undertaken using (i) archived soils amended by metal salts (MA soils; n=23) and (ii) topsoils collected from Nottingham, Wolverhampton and London (Urban soils; n=100). The resulting data was used first to quantify the factors affecting trace metal lability in the MA soils using a logistic (S-shape) model which described metal E-value primarily as a function of soil pH with secondary influences from other soil properties. It was apparent that mineral oxides were important fixation phases for Ni, Zn and Cd while Pb was strongly affected by organic matter in soils. This model, parameterised on soils contaminated originally by metal nitrate solution, was then applied to the Urban soils to reveal the extent to which contaminant source still controlled metal lability. A further investigation of the long-term effect of metal source on metal lability was pursued through a third dataset of rural roadside soils (n=42) which had received Pb mainly from petrol-derived and geogenic sources, defined by their isotopic signature. It was demonstrated that petrol-derived Pb remained more labile than Pb from the parent material, despite decades of contact, although both petrol-derived and geogenic Pb contributed to both the labile and non-labile fractions. In a fourth dataset, soils that had received Pb from sewage sludge amendment (n=16), the co-existence of high phosphate concentration from sewage sludge limited the magnitude and range of Pb lability, probably through formation of Pb-phosphate minerals. No consistent agreement was found between labile fraction of Pb and any single sequential extraction (SEP) fraction in all soils contaminated by Pb from multiple sources. Both empirical equations (extended Freundlich) and mechanistic models (WHAM-VII) were used to predict metal solubility in the MA and Urban soils. The advantage of using E-values (ME) over metal extractable by dilute nitric acid (MExt) to represent the reactive metal fraction in predictions of solubility was very clear for WHAM-VII, but not for the ‘locally parameterised’ Freundlich model. This was almost certainly due to the strong links between pH and E-value becoming subsumed into the coefficient nominally describing the direct influence of pH on metal solubility in the extended Freundlich equation. However, overestimation of the solution concentration from WHAM-VII was observed for all five metals, and strongly correlated with soil pH. Fractionation information from WHAM suggested that the source of the model’s underestimation of metal binding most likely lay with errors in the description of metal binding by Fe and Mn oxides for Ni, Zn and Cd and humic acid (HA) for Cu. An additional factor is the absence of potential binding phases in the WHAM model, such as particulate CaCO3, and the greater diversity of active adsorbents in soils at high pH values. WHAM is based on the assumption that all metal bound to HA is labile. However, in the current study, ‘non-labile’ Cu, Zn and Pb fractions were observed in suspensions of HA extracted from grassland and peat soils. These were quantified by measuring metal E-values and EDTA-extraction of HA-bound metal using size-exclusion chromatography (SEC) coupled to ICP-MS to separate free and HA-complexed metal forms. Evidence of time-dependent metal fixation by HA was found for all three metals during the course of a 40 and 160 day incubation study. The proportion of non-labile Cu held by HA could be 40-50%. The presence of a non-labile metal fraction held by HA may substantially invalidate the assumption of reversible equilibrium which is central to all current geochemical models of metal binding to humic substances.

Climate change is a consequence of changing in climate on environment over the worldwide. The increase in developmental activities and Greenhouse Gases (GHGS) put a strain on environment, resulting in increased use of fuel resources. The consequence of such an emission to the atmosphere exacerbates climate pattern. There are numerous Climate Change Downscaling studies in coarse resolution, which have largely centred on employing the dynamic approaches, and in most of these investigations, the Regional Climate Model (RCM) has been reported to numerically predict the local climatic variables. The majority of previous investigations have failed to account for the spatial watershed scale, which could generate an average value of downscaled variables over the watershed scale. To address shortcomings of previous investigations, the work undertaken in this project has two main objectives. The study first aims to implement a spatially distributed Statistical Downscaling Model (SDSM) to downscale the predictands, and second to evaluate the impact of climate changes on the future discharge and peak flow. It is conducted based on the IPCC Scenarios A2 (Medium–High Emission scenario) and B2 (Medium–Low Emission scenario). The main objectives of the study are as follows: • To generate fine resolution climate change scenarios using Statistical Downscaling Model in the watershed scale, • To project the variability in temperature, precipitation and evaporation for the three time slices, 2020s (2010 to 2039), 2050s (2040 to 2069) and 2080s (2070 to 2099), based on A2 and B2 scenarios, • To calibrate and validate hydrological model using historical observed flow data to verify the performance of the hydrological model, • To evaluate the impact of climate changes on the future discharge and future peak flow for three timeslices: 2020s (2010 to 2039), 2050s (2040 to 2069) and 2080s (2070 to 2099). Thus, to meet the objectives of the study, projection of the future climate based on climate change scenarios from IPCC is carried out as the most important component in the research. The results of this research are presented as follows: • The study indicates that there will be an increase of mean monthly precipitation but with an intensified decrease in the number of consecutive wet-days and can be concluded as a possibility of more precipitation amount in fewer days. • The watershed is found to experience increased rainfall towards the end of the century. However, the analysis indicates that there will likely be a negative trend of mean precipitation in 2020s and with no difference in 2050s. The precipitation experiences a mean annual decrease by 7.9%, 0.6% in 2020s and 2050s and an increase by 12.4% in 2080s corresponding A2 scenario. • The maximum and minimum temperatures are likely to be increased toward the end of the century by 2.7oC and 0.8oC respectively when compared to the current observed temperature (1975-2001) at the Subang temperature station. • The average annual mean discharge is predicted to be decreasing by 9.4%, 4.9% and an increase of 3.4% for the A2 and a decrease of 17.3%, 13.6% and 5.1% for the B2 scenario, respectively in the 2020s, 2050s and 2080s. • The average annual maximum discharge is projected to decrease by 7.7% in 2020s and an increase by 4.2% and 29% in A2 scenario for 2050s and 2080s, respectively. But there will most likely be a decrease in the maximum discharge for all the future under B2 scenario. It is projected a decrease of 32.3%, 19.5% and 2.3% for 2020s, 2050s and 2080s, respectively. • The projected mean discharge indicates a decline in the months from January to April and also from July to August in all the three future periods for A2 and B2 scenarios. There is an increasing trend in the discharge of September and October in the 2020s according to the A2 and B2 scenarios. • The highest increase in precipitation frequency occurs in 2080s under A2 scenario in which the increase in the magnitude of 100 Return Year is found to be 88% greater than the one of the maximum observed. • The highest increase in flood frequency at Sulaiman streamflow station occurs in 2080s under A2 scenario. The increase in the magnitude of 100 Return Year is found to be 26.5% greater than the one of the maximum observed.

Dust from mining activities is produced from several unit operations and is often a serious problem to the industry, due to the influence it can have on human health and the safety record and productivity of a mine. So far, legislative parties and the industry have approached dust as an issue that needs to be controlled, only when a mining operation or process generates undesirable particulates. Nevertheless, new legislation and standards, such as the EU IPPC directive (Integrated Pollution Prevention and Control) and air quality strategies aim to drive mining companies to incorporate dust assessment planning that will be implemented through the whole life cycle of the mine. Mitigation and monitoring practices as well as health surveillance programs will need to be clearly defined. This project’s purpose is to understand how mining processes and in particular how the mechanisms inherent within common unit operations (i.e transfer processes using haulage roads or conveyor belts, the tipping, loading and stockpiling process, the screening process etc) result in the generation of dust. If the operation of unit operations could by optimized to produce less dust, then a “fit-for-purpose” strategy for dust minimisation could be developed to follow exploitation, processing and production demand. The literature on dust from mining operations identified that generation of fines/dust occurs due to the presence of the mechanisms of abrasion and impact. Based on this logic, an experimental methodology was developed, which aimed to assess how dust was generated for each different mechanism and for a variety of ores of different mineralogy. Five different ores were tested, a limestone, talc, an iron ore, a lamproite and a copper ore and the same experimental methodology was followed for each. Experimentation using the HSE-WSL tumbling mill test determined that under the effect of abrasion, ores yielded higher dustiness values during longer tumbling times, whilst parameters such as the sample mass and the particle size distribution of the feed sample could also influence the dust generation patterns. The findings of the computational modelling (discreet element modelling) and experimentation (high speed video recording) suggested that control and optimisation of operational parameters (e.g mill velocity, or tumbling time) within processes that involve abrasion, such as the use of conveyor belts, mills, and screens could minimise the potential of dust generation by this mechanism. The use of a novel impact test determined a positive relationship between the energy input and the particle size distributions of the broken particles, as well as the accumulation of fine particulates in the range of dust (<75μm). Also an increase in the bulk volume of ores resulted in larger quantities of fine particulates. These observations suggest that it is possible to reduce dust in processes that involve drop from heights and impaction (i.e transfer points in conveyor belts, tipping, loading) by adjusting the energy input and the bulk volume of ore at impact to as low a level possible. Particle size analysis of the produced dust fractions were found to be material dependent and varied considerably for the different ores. Almost all materials produced significant amounts of ultra fine particles below 10μm and 2.5μm, both under impact and abrasion, which reveals the potential adverse impacts to the environment and human health. Quantitative mineralogical analysis using the mineral liberation analyser determined that the dust fraction presents a different composition to that of the ore. Comparison of the results collected for the five different ores using the HSE-WSL mill and the impact test identified that certain materials yielded high dust levels under abrasion and low under impact. Therefore it would be expected that dust control approaches for such materials would differ according to the mechanisms of the involved process and the mineralogy of the sample. According to the findings of this study a reduction in dust produced from mining unit operations could be possible by optimising the involved processes either by altering their operating parameters (drop height during tipping, velocity of conveyor belt) or by optimising the design of processes so as to reduce abrasion or impact. New legislation such as the EU IPPC directive has already started considering such an approach as important, and newly developed Best Available Techniques documents refer to this as the primary step companies should follow to minimise dust. Additional advantages of this approach are that it can reduce cost for dust control by making use of less conventional mitigation practices, and in the long term it could also minimise the utilization of energy and water going to suppression, extraction and dust collection systems. In certain cases the proposed route could also optimise the production chain, especially where the generation of fines is undesirable (e.g iron ore processing or aggregates production).

This dissertation is a contribution to two fields of study: applied social epistemology and the philosophy of technology. That is, it is a philosophical study, based on empirical fieldwork research, of social and technical knowledge. Social knowledge here is defined as knowledge acquired through the interactions between epistemic agents and social institutions. Technical knowledge is here defined as knowledge about technical artefacts (including how to design, produce, and operate them). I argue that the two must be considered collectively both in the sense that they are best considered in the light of collectivist approaches to knowledge and in the sense that they must be considered together as part of the same analysis. An analysis solely of the interactions between human epistemic agents operating within social institutions does not give adequate credit to the technological artefacts that help to produce knowledge; an analysis of technical knowledge which does not include an analysis of how that technical knowledge is generated within a rich and complex social network would be similarly incomplete. I argue that it is often inappropriate to separate analyses of technical knowledge from social knowledge and that although not all social knowledge is technical knowledge, all technical knowledge is, by definition, social. Further, the influence of technology on epistemic cultures is so pervasive that it also forms or 'envelops' what we consider to be an epistemic agent.