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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
201

Shear strength characteristics of mechanically biologically treated (MBT) waste

Fernando, V. I. Sudarshana C. K. January 2011 (has links)
Mechanical biological treatment (MBT) is the generic name for a group of processes which have been used to reduce the biodegradable content of municipal solid waste (MSW) in order to aid compliance with the Landfill Directive. As a result of mechanical biological treatment, MSW is converted to a material which has different properties to its parent material, including changes to its mechanical properties. The aims of this research were to identify: • The shear strength characteristics of aerobically treated MBT, processed at New Earth Solutions (NES) in the UK • Changes to the properties of the reinforcing elements due to the MBT process and its impact to the shear strength NES produced two fractions of MBT residue (0-10 mm and 0-20 mm) which were tested using direct shear equipment in order to identify the shear strength characteristic of the MBT residues. It was thought MBT might be a weak material compared to MSW due to the significant reduction of the reinforcing particles size and content, the results confirmed that MBT is a strong material (mobilizes its strength rapidly with displacement) compared to MSW. MBT processes lead to changes in both the content of reinforcing particles and their properties. The reinforcing effect and its impact on the shear strength of MBT waste was tested using direct shear. To an unreinforced basic matrix of either MBT or compost were added reinforcing elements in a controlled way to investigate the impact on shear strength from each identified reinforcement property.
202

Process improvement for the production of fermentable sugars using paper pulp derived from municipal solid waste

Puri, Dhivya Jyoti January 2014 (has links)
Sugar-lignin bio-refineries using renewable lignocellulosic carbon as an input material could be used in the future to produce a variety of value added products including fuels and specialty chemicals. The bio-refinery aims to replace a proportion of goods currently produced using fossil fuels. Lignocellulosic material has a significant sugar potential in the form of cellulose and hemicellulose and this can be accessed using enzymatic hydrolysis. The lignocellulosic feedstock used in this research was paper pulp derived from municipal solid waste (MSW) and the aim of the work was to maximise the efficiency of producing a concentrated sugar solution from the cellulose (or glucan) component of MSW using commercial enzyme preparations. Analysis of the pulp by acid hydrolysis showed a ratio of 56: 12: 27: 5 of Glucan: Hemicellulosic sugar chains other than glucan: Lignin & pseudo lignin: Ash on total solids (TS). The hydrolysis behaviour of this pulp was similar to that of other lignocellulosic substrates even though the matrix of this material is perhaps more complex. Glucan conversion could be increased by 6% if the pulp was extracted with acetone to remove solvent soluble compounds. Using the additive PEG 6000 increased conversion by 15 % over 48 hours, and allowed a 40 % reduction in the enzyme requirement. PEG also increased the centrifugal dewaterability of the substrate by up to 13%. These results were obtained in single stage batch experiments. It was found, however, that both the glucose concentration in solution and the overall glucan conversion in the substrate could be improved by using a two-stage hydrolysis strategy. Using 50 mg enzyme g-1 pulp at high total solids content >18.5% TS singlestage enzyme hydrolysis gave a maximum glucan conversion of 68%. It was found that two-stage hydrolysis could give higher conversion if sugar inhibition was removed by an intermediate fermentation step between hydrolysis stages. This, however, was not as effective as direct removal of the sugar products, including xylose, by washing of the residual pulp at pH 5. This improved the water availability and allowed reactivation of the pulp-bound enzymes. Inhibition of enzyme activity could further be alleviated by replenishment of β-glucosidase which was shown to be removed during the wash step. The two-stage hydrolysis process developed could give an overall glucan conversion of 88%, with an average glucose concentration of 7.5 wt% in 4 days after combining the hydrolysates of the first and second stage of hydrolysis. The residual washwater from the two-stage hydrolysis with intermediate wash step process contained a dilute amount of sugar. It was found that this washwater could be used as dilution water for a new batch of hydrolysis without any detriment to conversion efficiency. Thus, to further the work above a washwater recycle strategy was applied to the two-stage hydrolysis process. Washwater at various pHs and with or without the addition of PEG 6000 was used as dilution water for a subsequent round of hydrolysis, where up to 6 rounds of 48-hour hydrolysis were completed to reach a steady stage configuration. In these strategies the enzyme dose was reduced to 30 mg C-Tec3 g-1 pulp. Use of a pH 5 or pH 9 wash resulted in an increase in conversion of up to 5% in the first-stage hydrolysis rounds, indicating that enzyme carryover was occurring. The sugar augmentation and enzyme carryover consistently resulted in glucose yields above 7.0 wt% in the first stage hydrolysate when using this lower enzyme dose. The best result achieved in this strategy was obtained when using 0.25 wt% PEG 6000 in the reaction medium and washwater. By reducing the amount of liquid in the second-stage of hydrolysis, it was found that an overall average glucan conversion of 81% could be achieved over the two hydrolysis stages with an average glucose concentration of over 8 wt% in a 4 or 5 day reaction period. This result is significant, as it meets the downstream processing requirements for bioethanol, a major bio-refinery product, and does this with a low enzyme loading. Furthermore, the waste discharge is minimised due to the high glucan conversion.
203

Effect of dissociation on the properties of hydrate bearing sediments

Sultaniya, Amit Kumar January 2011 (has links)
Gas hydrates are clathrate hydrates, which are solid, ice-like compounds. Gas hydrates exist where there is an ample supply of gas and water combined with high pressure and/or low temperature conditions. In nature these are found in sediments where permafrost is present, and in deep-marine sediments. The morphology of gas hydrate within a sediment has a large impact on the strength and stiffness properties of hydrate bearing sediments. Gas hydrates are metastable and they dissociate if the temperature and/or pressure conditions are sufficiently altered. The dissociation of gas hydrate and its potential as a submarine geohazard have become of increasing importance as oil and gas exploration activities extend into significant water depths on continental margins and seas where gas hydrates are known to exist. Such activities may lead to dissociation of hydrate, possibly increasing pore pressure, and altering the stiffness and strength of the sediment. Due to difficulty in performing field testing and obtaining undisturbed in-situ samples for testing, at present, hydrate dissociation in the natural environment and its effects are hypothesised on the basis of remote observations. Therefore, a series of well-controlled laboratory tests were conducted on laboratory-prepared methane hydrate bearing sand sediments. The tests were undertaken with hydrate saturation ranging from 7% to 27% in the Gas Hydrate Resonant Column Apparatus (GHRC). Factors such as effective stress were also assessed with regard to specimen stiffness. Resonant column testing during hydrate formation and dissociation processes carried out for the first time, such that not only final change in specimen properties to be determined as a function of total hydrate saturation but also the change in specimen properties as function of the percentage of hydrate formation and dissociation. Test results showed that a rapid reduction in stiffness occurred for a minor change in hydrate saturation of sand specimens where dissociation was induced by temperature increase, but for specimens that were dissociated using the pressure reduction method a slower reduction occurred. In contrast, during hydrate formation stiffness increased more gradually. In addition, test results showed that the hydrate formation using the excess gas method led to higher increases in the shear stiffness compared to the flexural stiffness of specimens, and the linear stiffness threshold limit of hydrate bearing specimens were lower than the non-hydrate bearing sands. In addition to laboratory tests, an analytical model was built to predict the increase in pore pressure under undrained conditions within hydrate bearing sediment during dissociation. The results obtained from the laboratory tests were used to compare the predicted results from the model. Analytical model showed that the rise in pore pressure within a sediment was dependent on a number of factors: major factors were initial pore pressure, amount of hydrate dissociation, cage occupancy of gas within hydrate, stiffness of the sediment, and degree of water saturation; Minor factors were methane gas solubility in water, and methane hydrate density.
204

Experimental and numerical research on pharmaceutical aerosols

Ju, Dehao January 2012 (has links)
With the background of health issues regarding the consumption of tobacco, the widespread availability of safer nicotine products and a harm reduction policy is encouraged. A cigarette alternative is designed to deliver a dose of medicinal nicotine within a timeframe comparable to that of a cigarette, and gives much of what smokers expect from a cigarette without the risks of smoking tobacco. The general purpose of this Ph.D. project is to study the process of flashing atomization and dispersion, with a view to supporting the development of a cigarette replacement device. In order to test the effectiveness of the nicotine formulations, the analysis is carried out sizing the droplets of the aerosols at the position where human oropharynx locates, to support the further research on the deposition of droplets in the human respiratory tract. A mechanical lung has been assembled and programmed to trigger the ‘cigarette-like’ devices with different inhalation profiles, and a dual laser system has been designed to measure the global actuation flow characteristics (e.g. spray velocity and opacity). In order to efficiently acquire sufficient droplet information (e.g. diameter and aspect ratio) from images of in and out of focus droplets, a multi-threshold algorithm is developed and successfully implemented in the automatic particle/droplet image analysis (PDIA) system. It increases the depth of field (DoF) of small particles with diameters smaller than 50μm, and it performs more efficiently than the dual threshold methods which are widely used in the commercial software. A numerical multi-component two-phase actuation flow model has been developed, in order to test different formulations within various flow domains of the cigarette replacement devices. The simulated results of the numerical model have been validated with the experimental measurements and the results of previous researchers. In order to acquire an aerosol with relatively low and steady mass flow rate of nicotine, it is recommended that the mass fraction of propellant (HFA 134a) should be kept around 75%~90% to avoid the sharp temperature drop causing the sensation of freezing. The actuator nozzle diameter should be 0.2mm~0.3mm to produce a flow with relatively low mass flow rate. Furthermore the numerical model is capable of predicting the residual mass median diameter (MMD) of the spray, by using evaporation model of multicomponent liquid droplets, to quantify the sprays. Two different formulations with 95% and 98% mass fraction of HFA 134a, and two prototype cigarette alternatives with different expansion chamber volumes, have been analyzed by the numerical model and compared with the dual laser measurements. In addition, it considers the spray character by high speed imaging, with the special interest in the flashing phenomena and droplet sizes. It concludes that a larger expansion chamber volume enhances the propellant evaporation, recirculation, bubble generation and growth inside the chamber, and it made a significant improvement to produce finer sprays. Although the formulation with 98% of HFA 134a can generate smaller droplets, the formulation with 95% of HFA 134a produces more steady puffs with relatively low mass flow rate.
205

Synthesis and use of magnetic nanoparticles for the adsorption of mercury from water

Hakami, Othman January 2012 (has links)
This study used magnetite (Fe3O4) nanoparticles (NPs), mesoporous silica coated magnetite NPs (SCMNPs) and thiol functionalised silica-coated magnetite nanoparticles (SH-SCMNPs) for Hg(II) removal and recovery from water. The Fe3O4 NPs were prepared via conventional co-precipitation methods. Mesoporous silica coating was created on dense liquid-silica coated magnetite NPs (DLSC-Fe3O4 NPs) using cetyltri-methyl-ammonium chloride (CTAC) as molecular templates and followed by a sol-gel reaction. SCMNPs were functionalised with 3-MPTMS using the co-condensation method. Functionalisation of SCMNPs with this specific organic group was performed to enhance the selectivity of the magnetic NPs towards Hg(II). The characteristics of these particles were assessed at different stages in the production process. The hydrodynamic particle size distribution increased from an average diameter of ~75 nm for Fe3O4 NPs to ~105 nm after silica coating, and was found to be ~111 nm after functionalisation with thiol. The particles were found to be almost spherical with a uniform mesoporous structure with a pore size of ~2.1 nm. The particles were strongly responsive to an external magnetic field making separation from solution possible in less than 1 minute using a permanent magnet. Batch tests were used to evaluate the feasibility of the prepared NPs for the adsorption and desorption of Hg (II) from synthetic wastewater. SH-SCMNPs displayed a high removal efficiency for Hg(II) uptake, with 90% of Hg(II) removed during the first 5 minutes and equilibrium in less than 15 minutes. The adsorption efficiency was highly pH dependant. Adsorption was not affected by the majority of coexisting cations and anions under the conditions tested. 3 M HCl and thiourea in a 3 M HCl solution was an effective eluent for the desorption of adsorbed-Hg on SCMNPs and SH-SCMNPs respectively. This did not result in the destruction of the nanoparticles and they could subsequently be reused, without loss of their activity, in further adsorption tests. The adsorption characteristics of the particles were quantified in a series of isotherm experiments using Hg(II) solution concentrations of between 40 and 1000 μg L−1 at adsorbent concentrations of 4 and 8 mg L-1. The adsorption capacity was higher than for other commonly used adsorbents. Both the Langmuir and Freundlich isotherm models were applied to the isotherm data and the maximum adsorption capacity was achieved when the ratio of adsorbent to adsorbate was low. A semi-continuous method for using the process at a lab scale was developed and was found to be successful in the removal and recovery of Hg(II) and confirmed the results of the batch experiments.
206

Method development for enhanced antifouling testing using novel natural products against marine biofilms

Salta, Maria January 2012 (has links)
Marine biofouling is the accumulation of organisms on underwater surfaces, causing increased ship hydrodynamic drag, which results in higher fuel consumption and decreased speed and range. Biofilms constitute a major component of the overall biofouling and may lead to a 14 % increase in ship fuel costs. Past solutions to antifouling (AF) have used toxic coatings which have subsequently been shown to severely affect marine life. The prohibited use of these antifoulants has led to the search for bio-inspired AF strategies. Current approaches towards the production of alternative coatings include the incorporation of natural AF compounds into paints. Screening assays for novel AF compounds are often separated into two categories; toxicity and AF assays. Increasingly there is evidence that active compounds affect organisms at non-toxic concentrations, hence, the necessity for more insightful AF testing, such as bacterial and diatom attachment. This study assessed natural product (NP) antifouling performance of two marine seaweeds (Chondrus crispus and Bifurcaria bifurcata) and two isolated pure compounds from terrestrial sources (usnic acid and juglone) against two marine biofilm bacteria, Cobetia marina and Marinobacter hydrocarbonoclasticus. Overall it was found that all NPs affected bacterial attachment, however, juglone demonstrated the best AF performance against both bacterial species at a concentration range between 5 - 20 ppm. Biofilm colonisation is a surface related phenomenon, thus novel bioassays have been developed to directly test biofilm attachment and growth on NP-containing coatings for both static and hydrodynamic conditions. This study has incorporated NPs into a model coating system, using two formulations in order to assess their effect on biofilm growth. Laboratory screening of NP-containing coatings is often largely unexplored mainly due to difficulties in assessing their activity over short experimental time scales (typically only a maximum of a few days). To date there are only a limited number of reports on laboratory assessment for antifouling paints and their effect on biofilm growth and/or attachment. In this study, NP-containing model paints were applied on to coupons, placed in 24-well plates and then inoculated with the marine biofilm forming bacteria. This has been achieved by the development of a novel bioassay protocol that has allowed the in situ observation of biofilm formation and growth, by corroborating different techniques such as a multidetection microplate reader and confocal laser scanning microscopy (through nucleic acid staining). There was good correlation between the two techniques which showed that the NP containing coatings significantly inhibited biofilm growth and also revealed marked differences in biofilm structure (e.g. bio-volume, morphology and thickness). The goal of this study was to develop a new protocol to allow assessment of biofilm formation on coatings in a high throughput non-invasive manner. New protocols and methods using microfluidic devices were developed for the assessment of bacterial attachments and initial biofilm formation in the presence and absence of a NP under hydrodynamic conditions. This led to the development and fabrication of a novel lab-on-a-chip device for the investigation of the biofilm response to different hydrodynamic conditions. The microfluidic flow channels were designed using computational fluid dynamic simulations so as to have a pre-defined, homogeneous wall shear stress in the channels, ranging from 0.03 to 4.30 Pa, which are relevant to in-service conditions on a ship hull.
207

The green technology financing scheme (GTFS) in Malaysia : revealing the competency trap

Zaharudin, Mohd Azlan January 2017 (has links)
This research aims to understand the transition of established entrepreneurial firms into sustainable entrepreneurship ventures in Malaysia using a competency based perspective. The research considers established entrepreneurial firms attempts to acquire green technology financing. By observing a green technology financing scheme (GTFS) a competency trap is identified that constrains established entrepreneurial firms, regardless of their excellent financing track record and previous business success in other ventures. Utilising Rasmussen et al.’s (2011, 2014) evolutionary entrepreneurial competency framework, the research examines how established entrepreneurial firms develop the entrepreneurial competencies to overcome this trap and acquire green technology financing. By comparing different established entrepreneurial firms during the process to acquire financing, the research examined the GTFS contextual influence on the deployment of competencies, revealing the multi-faceted nature of the competency trap. In order to acquire GTFS financing the research identified two sets of entrepreneurial necessary competencies; (i) opportunity refinement competencies (ii) resource acquisition competencies. However, development of these competencies is influenced by the established entrepreneurial firms’ paths and the competency trap. Four different pathways to address the competency trap are highlighted. This emphasizes the need for more contextual based research at multiple levels of analysis to understand established entrepreneurial firms’ transition into sustainable entrepreneurship ventures.
208

Novel co-precipitated oxygen carriers for chemical looping combustion of gaseous fuel

Ekpe, Ngozi Chinwe January 2017 (has links)
Carbon Capture and Storage (CCS) is one option to meet the increasing energy demand as well as reduce net CO2 emissions to the atmosphere. Chemical Looping Combustion (CLC) is a promising CCS technology proposed to meet the challenge of mitigating the carbon dioxide (CO2) emissions. CLC process can be based on interconnected fluidized beds, consisting of air reactor, fuel reactor and oxygen carrier (OC) which undergoes redox reactions while it circulates between the reactors. The main products are CO2 and water, thus eliminating the need of an additional energy intensive CO2 separation. The feasibility of CLC depends on the oxygen carrier's (OC) ability to transfer O2 from air reactor to fuel reactor and have sufficient oxygen capacity, high reactivity and withstand a high number of redox cycles without significant loss in performance. OCs based on transition metal oxides of Cu, Co, Fe, Mn and Ni has been explored. Nevertheless, research is focused on improving the OCs performance with the aim to overcome their various practical limitations. Mechanical mixing and impregnation which fails to provide a high degree of dispersion and high metal loading respectively are commonly used for OC synthesis. Very few works have been reported for Mn-oxide and co-precipitated oxygen carriers. The few studies on co-precipitated OCs mainly use strong base as precipitants. One drawback to this is the repetitive washing of precipitate to remove excess alkali ions and controlled loading of active components cannot be easily obtained. In this study, weak base instead of strong base was used in the synthesis of OCs. This is the first time this controlled approach has been applied to prepare oxygen carrier in CLC for manganese and iron. This thesis is a novel research on development and detailed investigation of co-precipitated Mn-oxide and Fe-oxide OCs with ZrO2 and combined ZrO2–CeO2 support. The reaction kinetics, stability and oxygen transfer capacity (OTC) of the OCs were studied by TGA up to 1173 K in H2, CO and CH4. Characterization of physical and chemical structures of particles was obtained by SEM-EDX, XRD, BET and pycnometer. The result reveals that regardless of the composition of the co-precipitated oxygen carriers, there was no interaction of the metal oxides with the support material which could have altered the thermodynamics of the redox system. Furthermore, co-precipitated Mn/Zr and Fe/Zr OCs were more reactive than their counterpart prepared by impregnation and mechanical mixing. Also, changes in reactivity and OTC suggest that the synergistic effect varies with ratios of the single oxides in the bimetallic OCs. Co-precipitated Mn-rich oxygen carriers were more reactive than Fe-rich OCs. Interestingly, OCs with zirconia-ceria support exhibited activation tendency behaviour. Moreover, the use of combined zirconia-ceria for bimetallic Mn-Fe oxide reversed the characteristic progressive decrease in the performance of the OC with equimolar composition. For co-precipitated Mn-Fe Oxide oxygen carriers, zirconia content of 44 wt. % is sufficient to maintain the mechanical integrity of the particles during redox reactions compared to a zirconia content of 20 wt. %. This research has resulted in the development of highly reactive and stable oxygen carriers, which are promising for CLC. Mn/Zr OC reached full conversion in less than 48 secs and bimetallic Mn-Fe OCs reached 30% conversion in less than 43 secs in CH4 and maintained stability in a thirty multicycle test. The redox reaction kinetics of the most reactive oxygen carrier using CH4, H2, CO and air was investigated at isothermal conditions (973-1173 K) to determine the kinetic parameters. Models of the reduction and oxidation reactions were selected by using a model fitting method. The nucleation model was the most statistically significant and suitable model for describing the reduction and oxidation behaviour of the oxygen carrier. The values of activation energy obtained for the reduction reaction in CH4, H2 and CO were 142.8 KJ/mol, 32.95 KJ/mol and 26.37 KJ/mol respectively. Whereas, for the oxidation reaction, the activation energy obtained using air was 28.83 KJ/mol. In the application of co-precipitation technique for the synthesis of multicomponent materials, a heterogeneous product could be obtained from using improper preparation conditions. Results from this research have demonstrated that, the application of the well-designed co-precipitation procedure effectively produced composite materials (up to four co-precipitated mixed metal oxides) with controlled compositions and homogeneous dispersion. Furthermore, this study provides insight into the fundamental behaviours of co-precipitated manganese and iron based oxygen carriers to aid the design and optimization of future materials development.
209

Effective carbon adsorbents of solid looping technologies for post combustion carbon capture

Liu, Jingjing January 2017 (has links)
Carbon Capture and Storage (CCS) has been considered as one of the most promising techniques to reduce anthropogenic CO2 emissions in the atmosphere. As an alternative to replace the traditional technology of aqueous amine scrubbing, solid adsorbents looping technology (SALT) has attracted growing attention. Among various solid adsorbent materials, carbon-based materials with unique properties such as wide availability, relatively low cost, highly porous structure ease of regeneration, and stable cyclic performance, have been considered as promising candidates at both low pressure and moderate to high partial pressure. In this PhD research, activated carbon spheres derived from two different precursors, which are phenolic resin and coal-tar pitch, have been prepared and modified with potassium intercalation to improve CO2 capture performance for post combustion carbon capture. The project aims to investigate the factors that affect CO2 adsorption performance for post combustion carbon capture. Firstly, series of spherical activated carbon beads (with a uniform diameter of ca. 0.6-0.8 mm) derived from phenolic resin have been developed and characterised. The results show that the surface polarity can be enhanced by potassium intercalation. The intercalation of potassium significantly increased the CO2 capacity of the AC beads by a factor of up to 2 at 0.15 bar while the effects of the treatment on their mechanical strength and morphological features were negligible at KOH/AC mass ratios of 0.3 and below. The factors other than adsorption that affect the performance of phenolic resin derived carbon spheres were also investigated in terms of adsorption kinetics, cyclic performance, heat of adsorption, the effect of moisture, and regeneration heat. Secondly, coal tar pitch derived activated carbons, with uniform spherical diameter of 1-2 mm were synthesised via two different activation approaches, which is firstly an initial steam activation followed by KOH activation, and secondly one-step KOH activation, both with mild KOH/carbon mass ratios. Samples prepared with one-step KOH activation method had shown a better microporous structure and a higher CO2 adsorption capacity. Owing to the narrow micropores and K-doping, the samples demonstrated outstanding CO2 capacities at relatively low CO2 partial pressure. Multicycle stability was examined over 50 cycles of adsorption and desorption, and both samples present excellent adsorption kinetics and regeneration ability. Finally, the volumetric CO2 uptake of best performing samples were also calculated and compared with other candidates. Based on our previous results, further investigation towards the influence of precursor materials and correlation between microporosity pore size ranging from 0.4 nm to 2 nm and CO2 uptakes have been carried out. Future work on how to improve the CO2 sorption performances of the studied materials has been proposed.
210

Bioremediation of estrone from water matrices using the enzyme laccase combined with mathematical modelling

Jenidi, Youla January 2017 (has links)
The presence and impact of steroid estrogens in natural water matrices has driven development and evaluation of wastewater treatment technologies that may reduce the steroid load entering water environments. This work was undertaken to assess and predict the ability of Trametes versicolor laccase to degrade estrone (E1) in water matrices under realistic conditions to wastewater treatment plants (WWTPs) and with consideration of the complex and variable nature of the wastewater matrix. A robust experimental procedure was developed to ensure the efficiency of the enzyme laccase to degrade E1 in water matrices was not overestimated due to errors arising from poor experimental design. These experiments demonstrated that commercially-obtained laccase in concentrations above > 1 mg/ml are inhomogeneous requiring centrifugation prior to use to reduce error and provide more accurate evaluation of laccase capability. Sample filtration, which is necessary for chromatographic analysis, identified regenerated cellulose (RC) membrane filters as the optimum filters for particulates removal from E1 solutions due to their low affinity toward E1 (3.2 ±1.72 %). An optimum enzyme inactivation procedure using hydrochloric acid was also developed to ensure that the enzyme laccase was instantly inactivated without affecting the target steroid E1 itself. Using the established experimental procedure, bench-scale studies evaluating the efficiency of laccase-based treatment in a ‘clean’ water matrix were investigated. Experiments in deionised water provided a proof of concept of laccase ability to degrade E1 in water under realistic ranges of temperature [6˚C - 25˚C] and contact time [0.5 hr – 8 hrs] to the WWTP and evaluate the use of models to fit experimental data and predict within that system. Box Behnken Design (BBD) was applied to determine the number and the conditions of the performed experiments. The experimental data was then utilised to build two different models to predict E1 removal efficiency under any set of conditions and optimise the performance of laccase-based treatment system. The goodness of the fit for each model was tested using statistical indices such as coefficient of determination (R2), mean squared error (MSE) and absolute average deviation (AAD). The artificial neural network (ANN) model showed a better fit to the experimental data than the response surface methodology (RSM) model (RSM and ANN of R2 = 0.9908 and R2 = 0.9992 respectively. In addition, the predictive capabilities of RSM and ANN were tested using a set of statistically designed unseen data that was not previously used in models’ training. Both models showed limited predictive capabilities. The ability of laccase-based treatment to remove E1 in real-world wastewater was studied at bench scale. To account for the complexity and variability of the wastewater matrix, effluent samples during the period December 2014 - June 2015 were characterised for standard water quality parameters, where the temporal variation in wastewater chemical oxygen demand (COD), total suspended solids (TSS) and pH, were observed. A new water quality parameter, “Benchmark” was also developed and applied to quantify the impact of wastewater variability on laccase performance for E1 removal. The average benchmark value in the period between December 2014 and June 2015 was 79.8±3.7%. In addition, the impact of laccase inhibitors, which are likely to be present within the wastewater matrix, such as chloride, copper, iron and zinc, on laccase activity was investigated. The inhibitory effect of chloride ions increased with increasing chloride concentration above 200 mg/l. Copper and zinc ions exhibited negative effects on the enzymatic degradation of E1 at concentrations equal or above 10 mg/l and 200 mg/l. The impact of water matrix temperature, contact time and laccase concentration were studied in wastewater effluent and the experimental data was used to build RSM and ANN models. The predictive capability of the generated RSM model was relatively poor (R2 = 0.863) and even lower than the achieved predictive capability in clean matrix when tested using unseen data, this was partially attributed to the variability of wastewater matrix that could have not been addressed in this type of models. Whilst the improved ANN model showed a better predictive capability than RSM (R2=0.991) An advantage of the ANN model compared to the RSM model and reported for the first time, was the ability to include the impact of matrix complexity and variability on laccase performance, assessed via the benchmark data added as a forth factor in the ANN model. The final ANN model incorporating the matrix variability observed temporally during the sampling period had extremely high predictive capabilities (R2 > 0.99). This model approach holds the potential to help researchers evaluate and optimise laccase-based treatment (as well as other treatment technologies) and predict the removal efficiency of various bioactive chemicals under a wide range of conditions. Performing laccase-based treatment in a continuous reactor, utilising actual wastewater effluent and under realistic conditions to WWTPs, is the next stage that should be investigated in detail.

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