ABSTRACTS

Condition Monitoring of a Large-scale PV Power Plant in Australia AMIT DHOKE

Condition monitoring of solar photovoltaic (PV) plants is essential to detect and diagnose faults. Condition monitoring of a PV plant includes performance analysis, energy loss measurement and detection of operational issues to eliminate the possibilities of safety hazards. This paper proposes a PV output prediction model. This model is used to identify common faults in PV system by comparing voltage and current with respect to threshold, predicted values and between strings. The procedure to calculate threshold is described and comparative analysis used to identify the faults. A simulation study is carried out with real-time plant data. The string disconnection and bypassed module faults were detected using string level monitoring with the measurements of operating voltage and current. The results were analysed for accurate fault detection and found that the string comparison method could be more reliable for monitoring and an accurate fault detection. Characterisation of proppant transport in hydraulic fractures using the coupled lattice Boltzmann method and discrete element method DUO WANG

Hydraulic fracturing was first employed in the 1940’s, and soon became one of the most popular techniques for the stimulation of unconventional gas reservoirs. The hydraulic fracturing process involves the high-pressure injection of an engineered particle suspension, comprised of the base fluid and high-strength particles referred to as proppant, into a wellbore. The aim of this research is to develop a particle-scale computational model that can provide fundamental new insights on proppant injection. In the developed model, the fluid phase is characterised using the lattice Boltzmann method (LBM) while the proppant phase is modelled by the discrete element method (DEM). For the fluid-particle system, the LBM and DEM are coupled via an immersed moving boundary (IMB) condition. The outcomes of this research could generate new understandings that hopefully would result in the improved efficacy of hydraulic fracturing.

Highly compact and uniform CH3NH3Sn0.5Pb0.5I3 films for efficient panchromatic planar perovskite solar cells

MIAOQIANG LYU

Organolead halide perovskites have recently been brought to the forefront of photovoltaic research due to their advantages, such as capability of solution-process, low band-gap, high absorption-coefficient, excellent carrier mobility, enable their applications in low-cost and high efficient solar cells. To fabricate efficient planar perovskite solar cells, a low optical band-gap and highly uniform perovskite film on the substrate are two prerequisites. In address these two critical issues, we demonstrate that a chlorobenzene-assisted spin-coating method can be very effective for preparing highly uniform and compact mixed lead-reduced perovskite CH3NH3Sn0.5Pb0.5I3 films with a very low optical band gap (1.23eV).

Energy Generation and Harvest

A power conversion efficiency of ~7% is achieved for a panchromatic planar configuration using a low-temperature, solution-processable method, which is among the best-reported performance for panchromatic planar perovskite solar cells with a light-absorption over 1000 nm. Methane Transport in Australain coals HLA SHWE

Coal is considered as a unique and unconventional reservoir with characteristic intrinsic properties which make understanding methane transport in coals as a challenging research work. As commonly agreed, coal is composed of two parts of porous spaces in which gasses can form predominantly as adsorbed state in the matrix and partly as free gas in cleat system of coals. It is equally important to determine the storage capacity as well as the gas transport mechanism in coal. As nature of coal varies across the continents, it is worth to mention; this research works dedicated to Australian coal (Surat Basin). The comparison of the type of coal and the petrological composition, proximity analysis results will be presented. The research work includes the experimental and modelling works since all modelling results need to be validated with hard data and vice versa. ... Using existing theories such as Fick's law, Langmuir to model gas concentration changes in relation to time and ....

Cesium-doped perovskite solar cell with enhanced performance and stability PENG CHEN

Although the best perovskite solar cell (PSC) has achieved 22.1% power conversion efficiency (PCE), the stability of organolead halide perovskite materials in ambient condition remains the most serious issue to prevent its further commercialization. By partially replacing the organic cations with inorganic cesium, the hybrid perovskites exhibit better moisture stability, as well as improved photovoltaic performance. Herein, the influence of substituted cesium with different doping concentrations in PSC has been studied, and the optimized morphology and interface as well as improved crystallinity are responsible to enhancing stability and performance under high humidity environment. Numerical analysis of thermo-hydrodynamic performance of helical-coil heat exchangers operated with ice slurry AMIN KAMYAR

Helical-coil heat exchangers offer a significantly enhanced thermal performance once they are operated with ice slurry (biphasic refrigerant). This is due to the superior heat transfer capability of ice slurry as a phase change material. The use of ice slurry contributes to substantial reduction of operating cost as a result of the decrease in the charge of primary refrigerant and the increase of heat exchanger load capacity. This paper presents a numerical study on the thermo-hydrodynamic performance of ethyl-alcohol ice slurry in a helical-coil heat exchanger. The flow and thermal behaviours as well as the entropy generation in the heat exchanger are examined. The results indicate that as the ice mass fraction and the Dean number increase, the rates of heat transfer rate and entropy generation increase. However, the contribution of heat transfer on the overall entropy generation decreases.

Effect of vertical deviatoric stress on the permeability of coal in face cleat direction SYED SHABBAR RAZA

It has been long understanding that permeability of coal is strongly depend up on the mechanical stress on the coal seam gas reservoir (CSG). The assumption of constant confining stress on the CSG reservoir leads to the conclusion that over the pressure drawdown period, the permeability of CSG reservoir will decrease. This understanding was also supported by the laboratory data that used the tri-axial stress to apply the constant confining pressure. Although, it is been observed in many CSG reservoir that permeability either remain constant or increase with pressure drawdown. To understand this phenomenon, a series of experiments are conducted to investigate the permeability evolution of coal sample as function of pore pressure, applied stress and deviatoric stress. Result shows the incease in the permeability of coal in the face cleat direction when the deviatoric stress increased parallel to face cleat direction.

Impact of flow regimes on coal fines generation during Coal Seam Gas production process TIANHANG BAI

The study presents the development of a fully coupled numerical model that integrates different flow regimes and the generation of coal fines. The Scanning Electron Microscopy was employed to obtain coal cleat geometry. The combination of shear and tensile failure criteria was selected to evaluate the generation of fines. The results reveal that more coal fines are generated in two-phase flow than single-phase flow. For two-phase flow conditions, residual displaced phase is observed inside the micro-roughness of cleat. Most coal fines are generated in these regions due to the substantial pressure difference between the trapped phase and the invading phase. Coal wettability plays an important role in coal fines creation. Using the wetting phase as the invading phase will produce one order of magnitude more coal fines than that from the other way. The change of fluid phase in the cleat creates considerable pressure fluctuations, which is unfavourable in managing the production of fines. Computational modelling of counter-current multiphase flows in annulus piping

TRAVIS MITCHELL

The bottom hole pressure (BHP) in natural gas wells is an important parameter in the effective design of well completions and artificial lifting systems. Poor estimation of this can lead to liquid loading in the wellbore and reduced efficiency of the extraction process. The complex interaction of gas and associated water can increase the uncertainty in pressure gradients and ultimately affect BHP estimation. A significant body of research has explored pressure gradients in the co-current multiphase flows found in conventional gas extraction, but these are not expected to hold for the counter-current regimes present in coal seam gas (CSG) extraction. Therefore, this research aims to develop a computational fluid dynamics model of simultaneous gas and fluid transport in CSG wells. This will provide fundamental new understanding of the influence of volume fractions on flow regimes and the pressure profiles for various subsurface conditions. Transient heat transfer at the proppant-fluid interface of hydraulic fracturing fluids

JON MCCULLOUGH

Existing methodologies for modelling the suspension properties of hydraulic fracturing fluids typically focus on large-scale macroscopic flow behaviour. However, this loses fundamental details relating to both the hydrodynamic and thermodynamic interactions that occur between the proppant and fluid phases. This may result in the reduced effectiveness of a hydraulic fracturing stimulation operation. A lattice Boltzmann framework is utilised to study heat transfer at the interface between two disparate media and compared to analytical solutions. Resolving this within a fracturing fluid may allow the development of strategies that optimise proppant transport by taking advantage of local convection behaviours. Introducing a two-dimensional experimental model for investigating hydraulic fracturing FARZIN HAMIDI

Characterizing crack initiation and propagation in a brittle rock medium is an important topic in all geo related areas such as mining, reservoir and geotechnical engineering. Most of the previous physical models used rock which lead to inconsistent results since rock samples underlie statistical variations. Thus, there is a need to use a material to keep the mechanical parameters constant for all sample during a parametric study. An experimental investigation on different material has been conducted in order to find a suitable substitute materials of low strength for brittle rock. Indirect Brazilian Tensile Strength (BTS) and Uniaxial Compressive Strength (UCS) are carried out to find their properties. This paper reviews current literature in synthetic rock materials, describes experimental procedure, introduces preliminary results and presents conclusions.

Model Driven Control System for Power Distribution Grids Equipped with Medium Scale Photovoltaic Generation

JAROSLAW KRATA

This presentation focuses on a novel real-time model driven control applied to a power distribution grid highly penetrated by photovoltaic generation. The research explores an issue of intermittent voltage fluctuations caused by typical weather conditions such as shade from moving clouds. In order to avoid unwanted sudden changes of voltage magnitude, a new control strategy has been proposed. The centralized controller with a built-in grid model predicts the future state of the grid according to an intermittent disturbance. The multidimensional, non-linear mixed integer optimization procedure is applied to find the most optimal grid response. The novelty of the method relies on the fact that the controller works in real-time and delivers globally optimized set-points. To verify the controller performance, complex simulations were performed basing on a real network. Obtained results indicate that the new controller can significantly help to mitigate intermittent voltage fluctuations.

LMI-based Robust Voltage Control for Utility-scale DFIG-connected Wind Turbine

SURINA MAT SUBOH

Energy Transmission and Distribution

The presence of turbulence will impact the loads on the turbine and, ultimately, its life span and produce undesired power flickers. LMI-based robust control method will be proposed. The controller will be specifically designed for 2MW wind turbine under turbulence and gusty wind condition. The main objective of the proposed voltage controller is to maximize the power capacity under rated wind speed. The control performances will be compared to the conventional PI controller in terms of stability and transient responses behavior. It is found that the proposed controller is robust to wind speed uncertainties.

Investigation of Non-Synchronous Penetration Level and Its Impact on Frequency Response in a Wind Dominated Power System

NAHID-AL MASOOD

Recently, most of the wind power plants in South Australia have been constructed using variable speed generators, which do not offer frequency control functions. These machines and a high voltage DC interconnection to Victoria often cause a higher level of non-synchronous generation in South Australia. During such cases, South Australian system may rely on a few synchronous machines for frequency control. Under such operating scenarios, a big contingency could result in unacceptable frequency deviation and under frequency load shedding. To explore this issue, this research evaluates non-synchronous penetration level in South Australia and investigates its effect on network frequency response.

Integration of MW Scale Fast Charging Stations for Electric Vehicles into the Power Grid

MOHSEN AHMADI

This presentation, provides a topological survey of charging stations available in the literature and evaluates them based on grid support, power density, modularity and other factors. Next, the most suitable topology for a fast charging station is selected and then the effect of simultaneous fast charging of EVs on the grid is investigated. The results show that the power required for a fast charging station introduces a very large voltage deviation at the point of common coupling and ultimately makes the charging station unstable. To mitigate this problem, the authors propose a bidirectional DC fast charging station with dynamic load control to address voltage drop and overload issue in weak and/or highly loaded distribution grids. By dynamic control of charging process, the proposed charging station maintains the voltage at the point of common coupling and prevents overloading in the incoming lines even when the charging power demand is more than the charging station capacity.

Voltage Management of Large Scale PV Systems Using an Optimal Power Factor Droop Control Scheme

LICHENG WANG

An optimal parameter setting approach for PV inverter power factor droop control scheme is proposed to enhance its voltage regulation performance. Firstly, an innovative method using a voltage-PV generation curve is developed to analyze the voltage response with respect to fast fluctuating PV generation. Then, on the basis of this voltage-PV generation curve, an optimization problem is established to calculate optimal parameters of the power factor droop control scheme considering the coordinated operation with a Step Voltage

Regulator (SVR). After the implementation of this approach, both voltage fluctuations and the amount of SVR tap changes are greatly mitigated.

Investigation of Voltage Performance of an LV Distribution Network for Improving Rooftop Photovoltaic Uptake in Australia

SHOHANA RAHMAN DEEBA

Recently, Queensland state of Australia has seen a rapid growth in rooftop solar photovoltaic (PV) installations. However, the growth can be throttled due to voltage violation constraints at the distribution feeder level. Consequently, distribution utilities in Queensland have set a guideline for new PV inverter connections. During light load condition and under high availability of PV power, voltage rise may exceed its acceptable range in some buses even after the PV inverters are operated at specified lagging power factor given by the aforementioned guideline. To address the above-mentioned issue, this work investigates the impact of upcoming PV units on voltage performance of a Queensland distribution system. This study also determines an allowable power export limit of a new PV inverter by satisfying standard voltage margins. This limit is utilised to develop a battery control strategy.

Plugging Well with Bentonite: Review of the Technology and New Lab Results

AMIN MORTEZAPOUR

Application of bentonite to plug oil& gas wells has shown successful application in US, Nigeria and Australia. The general advice is plugging wells with bentonite rather than traditional cementing is cheaper and beneficial in terms of self re-healing properties. The aim of this presentation is to review the application of bentonite in different places of world (Nigeria, Australia and US) and also present the results of new lab experiment that is performed in University of Queensland. This research is directed at saving 20-50% of the cost of well abandonment, while at the same time increasing the reliability of the plug. In Queensland thousands of CSG wells are currently being drilled and Queensland has at least one operating bentonite mine. The forecast is showing 40,000 wells will be drilled till 2030 and eventually need to be plugged.

A novel PV output power forecast framework for PV integrated smart buildings

MUHAMMAD QAMAR RAZA

The uncertainty associated with PV output power is one of major drawbacks of PV technology for higher penetration in residential areas and power grid. Therefore, an accurately forecast of the PV output power is utmost important for reliable and secure electrical energy supply. In this research study, a novel feed forward neural network (FNN) ensemble based forecast framework is proposed. Correlated variables such as wavelet transformed PV output power data, solar irradiance, temperature, humidity and wind speed are applied as inputs to precisely forecast the output power. Trim aggregation technique was applied to combine the output of ensemble network after removing the upper and lower forecast extremes. The proposed forecast framework depicts higher forecast accuracy than the comparative persistence, time series and neural network based forecast models.

Feasibility Study of Replacing SF6 Breakers with Air Interrupters in Australian Remote MV Feeders

ASIF ISLAM

This paper investigates the electrical stress at different locations of a power system and indicates the possible locations where SF6 breakers can be replaced with air interrupters. Arc conductance time constant has been varied to find out the optimum condition of successful arc switching at the remote locations of Australian MV distribution networks. Arc of different lengths (5, 20, 100 and 500 mm) and time constants (1, 10, 40, 80 and 140 µs) have been simulated and the critical rate of rise of transient recovery voltage for successful interruption is plotted against arc current for all cases. It has been found that in Australian 11 kV network, the arc time constant around 30 µs for rural areas and around 20 µs for semi-rural areas may be a suitable condition to develop new type of air interrupter to replace SF6 interrupters in these areas. Possible techniques to reduce the time constant of air arc from 140 µs to prescribed values are outlined at the end of this paper.

Moisture dependent fluctuations in power transformer winding clamping pressure

LAKSHITHA NARANPANAWE

Power transformer winding clamping pressure (CP) is a main parameter, which determines its short circuit withstand capability. Progressive loss of clamping pressure is a common phenomenon, which can be observed in power transformers. It has been identified that changes in the moisture content and repetitive compression cycles on pressboard during high current faults tend to change the winding CP. Hence, this study set of laboratory experiments and Finite Element modelling based simulations were performed to investigate above phenomenon on a 400kVA three phase distribution transformer winding. From both laboratory experiments and simulations, it was found that power transformer winding CP is highly sensitive to changes in moisture content.

Microgrid Impact on Low Frequency Oscillation and Resonance in Power System

AWAN KRISMANTO

Renewable technology based Micro Grid (MG) are mostly implemented with power electronic devices. Those MGs have no or very small aggregated physical inertia. Reduction in system inertia may have negative influence on stability. Conversely power injection from MG might reduce line congestion, stress on generators and improve damping performance. In this paper, a two-area power system with MG is connected in one area is thoroughly investigated. Eigenvalues analysis shows that damping of inter-area and local modes enhanced as MG penetration increased. For variation in system operating conditions two neighboring eigenvalues coincided and interacted. Furthermore, a weak resonance phenomenon is detected. With increasing of penetration of MG, the detected resonance becomes weaker. Eventually, the resonance can be prevented and system stability can be maintained.

Energy Device for Post Lithium-ion Battery YUXIANG HU

Smart Materials

Nowadays, the Metal batteries are acting more and more important role in our society, such as the portable devices, various vehicles, and power storage system. However, there exist amount of problems on the costing and energy density for current used Li-ion batteries. Developing high energy density, environment friendly, low cost batteries are still important challenge for us. Recently, researchers focus on the investigation about the post lithium-ion batteries, such as lithium-air batteries, sodium batteries, aluminum batteries and so on, which own high energy capacity and low cost comparing with lithium-ion batteries. In this presentation, I would show some kinds of post lithium-ion batteries energy storage devices, which have amount of application potential.

Bio-derived Carbon Material as Dual Performance Anodes in Sodium and Lithium-ion batteries

ROHIT RANGANATHAN GADDAM

Choosing sustainable and eco-friendly materials in energy storage is essential for todays’ battery technology. Using biomass derived carbon anodes in batteries for energy storage will enable lesser dependence on fossil fuel, thereby increasing the affordability of anode material without compromising the performance. The present work reports the development of novel bio-derived carbon materials (CM) from renewable precursors to produce high performance lithium-ion battery (LIB) and sodium-ion battery (NIB). Tested against sodium, the CM delivered a discharge capacity of 277 at a current density of 100 mAg-1 in the second cycle. For LIBs, the discharge capacities of CM was 741 at a current density of 100 mAg-1 in the second cycle. The present work has the following advantages: (i) the precursor is cheap and widely available, (ii) the synthesis method is scalable, and (iii) the obtained carbons show good performance in both NIBs and LIBs.

V2O5 modified by Cu-doping as promising cathode materials for lithium-ion batteries

PENG LIU

V2O5 is a potential cathode material for next-generation lithium-ion batteries due to its high theoretical capacity. However, its application is hindered by low electronic and ionic conductivities. In the present work, V2O5 was doped by various contents of copper to minimize the drawbacks of pure V2O5. The electric conductivity of V2O5 was greatly enhanced by Cu doping. Cu-doped V2O5 also exhibited excellent cycling and high-rate performance. Therefore, copper doping is an outstanding strategy to develop high-performance electrode materials for lithium-ion batteries.

Biomass and biomass-derived carbon electrodes for supercapacitors

HAO LU

The limited resources and availability of fossil fuels as well as the severe impact of burning them on climate change have been driving the world to exploit and use increasingly high proportion of sustainable and clean energy, while energy storage systems, such as batteries and supercapacitors, play a foremost role in its practical application. Meanwhile, with a fast-growing market for mobile, portable and high-power energy storage system, SCs are attracting increasingly more attention. During the past decade, more and more academic communities and companies have focused their research on SCs. And one of the most hot and challenging research direction is to synthesize electrodes of excellent performance, environmentally friendly and cost effective. Biomass most often refer to plants or plant-

derived materials as well as marine organism-derived materials. In my research, I mainly focus on biomass materials especially cellulose related materials.

Metabolic study of poly (3-hydroxybutyate) production from methane in a mixed culture

PAWARISA LUANGTHONGKAM

Methane-oxidizing bacteria (methanotrophs) are capable of growth on methane and attractive for methane-based biotechnology, including a production of poly-β-hydroxybutyate (PHB), a biodegradable bioplastic. Methanotrophs can accumulate a large amount of intracellular PHB in response to the limitation of essential nutrients. A challenge for a sustainable production of the high-value product is an application of eco-biotechnology, with processes employing natural mixed culture, which has showed difficulties in the physiological and genetic alterations. With current molecular techniques, we aim to characterize genetic properties and dynamic coupling between individual microorganisms involving a synthesis of intracellular PHB from methane. It has been expected that a system modelling approach would provide an effective tool for predicting metabolic parameters and improve our knowledge of symbiosis insights through PHB production from a methanotrophic mixed culture.

The Study of Novel Anode Materials for Sodium Ion Batteries

JINGWEN ZHU

To satisfy the growing energy storage demand of renewable energy, electrochemical energy storage (EES) technology attracted great research efforts in the past decade. While Lithium-ion batteries (LIBs) possess high energy density, the lack of lithium resources limits its wide application as EES devices for the storage of renewable energy. Of late, sodium-ion batteries (NIBs) was considered as the most appealing alternative to LIBs for its low cost and abundant resources in earth crust. However, graphitic carbons, the basis of the most common negative electrode material for LIBs can only accommodate very small amount of

Na+ due to its larger ionic radius compared to Li+. Therefore, the lack of suitable anode

material obstructs the application of NIBs. At the current stage, the objective of this work is to explore novel two-dimensional (2D) materials with well-defined geometry, good conductivity, and flexibility as high performance anode materials for NIBs.

Experimental and numerical investigation on one-dimensional diffusion of calcium chloride solution into alginate solution for Ca-alginate gel formation

BOON-BENG LEE

Ca-alginate microgels are popular for various encapsulation applications. The impinging aerosols method is one of the methods that can produce the microgels in large scale. The gelation of the microgels produced by the method is limited by a short contact time and the amount of CaCl2 present on the alginate droplets. The aim of this study is to investigate the Ca-alginate gel formation kinetics when a limited amount of CaCl2 solution is present. Formation of the gel was studied using the Murexide as the Ca2+ cations complexometric indicator. The gel length increases as CaCl2 concentration increases. In contrast, the gel length increases as alginate concentration decreases. A sufficient amount of Ca2+ cations is required to ensure the gelation progresses continuously. On the other hand, the length of CaCl2 solution diffused through alginate solution was computed using the one dimensional diffusion model. The computed results were compared with the experimental results.

The influence of real gas effects on the performance of supercritical CO2 dry gas seals

MOHD FAIRUZ ZAKARIYA

One of the main challenges of sealing supercritical CO2 with dry gas seal is that seal operating conditions are near the critical point. The current work investigates dry gas seals operation with supercritical CO2 at two operating conditions using CFD.One close and one far from the critical point. For each condition the effect of using a real gas in comparison to an ideal-gas is explored. At the operating condition far from the critical point a maximum change of 1.7% in pressure, 0.4% in temperature and 1.1% in density are observed. Contrary, closer to the critical point a maximum change of 6.5% in pressure, 6.7% in temperature and 39.5% in density are observed. These changes also influence opening force and leakage rate. Far from the critical point the maximum changes are 0.7% and 3.1%, whereas close to the critical point maximum changes of 3.4% and 10.3% are observed. The work also shows that centrifugal effect plays an important role when operating with dense gases.

Surprisingly advanced CO2 photocatalytic conversion over thiourea derived g-C3N4 with water vapor while introducing 200-420 nm UV light ZHUXING SUN

200-420 nm UV light was for the first time introduced for CO2 photocatalytic reduction over graphitic carbon nitride (g-C3N4). It was surprisingly found that thiourea derived g-C3N4 (TCN), which showed inferior activity in CO2 reduction under visible light irradiation, exhibited more remarkable CO2 conversion efficiency under > 200 nm light irradiation compared to g-C3N4 synthesized from urea (UCN) and commercial TiO2 (P25). Also, the highest selectivity to CO2 conversion was observed over TCN while P25 showed the most prominent H2 production followed by UCN. Through a series of characterizations, proposed reasons are given.

Enrichment of methanotrophic mixed culture for higher PHA accumulation capacity

SYARIFAH NURAQMAR SYED MAHAMUD

PHA production via mixed microbial cultures (MMCs) based on low cost carbon source (methane) is gaining interest as it can minimize production cost by eliminating the need for sterilization equipment and aseptic operation. The most recognized process to select the microbial populations with enhanced capacity to store PHA from MMC is the Feast and Famine process, in which the MMCs are subjected to continuous shift of external substrate excess and limitation. While many studies have succeeded in the enrichment of highly effective PHA-accumulating populations from activated sludge, the influence of the conventional feast-famine strategy on PHA production by methanotrophs has hardly been investigated. In this study, we aimed to gain a better understanding of the effect of feast-famine strategies on the capacity of a mixed methanotrophic culture to accumulate PHA.

Improvements in the thermal and mechanical properties of wood flour / polyhydroxyalkanoate (PHA) composites through the addition of non-reactive additives: boron nitride and talc

CLEMENT CHAN

Polyhydroxyalkanoates (PHAs) have received substantial attention within the field of wood plastic composites because of their biodegradability and low melt viscosity. However, the brittleness and slow crystallisation rate of PHAs remain the main obstacles to their broader use. To overcome these challenges, a study was conducted to explore the effect of a nucleating agent (boron nitride, BN) and an inorganic filler (talc) on the mechanical properties of pine wood flour / poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) composite. Through the addition of 10 wt% talc, the stiffness of the composites was significantly increased. Furthermore, BN significantly improved the rate of crystallisation of PHBV, as evidenced by Avrami analysis.

Robustness of steel moment resisting frames against sudden column loss considering the effect of span length

FARSHAD HASHEMI REZVANI

In this study, the effect of span length on progressive collapse resistance capacity of welded unreinforced flange – bolted web (WUF-B) connections was investigated by using the alternate path method as per Unified Facilities Criteria (UFC). Towards this aim, several nonlinear analyses were performed for three generic mo-ment resisting frames with WUF-B connections considering various span lengths. In order to reduce the simu-lation time, a macro-element, or component-based model is introduced and verified against the NIST test results. The analysis results revealed that for a certain frame length, by decreasing the span length (increasing the number of spans) as an indirect approach, it is possible to enhance the alternate path capacity of WUF-B con-nections and decrease the risk of progressive collapse occurrence. For example, for the cases studied here, it was shown that by decreasing the span length to half the failure overload factor of the frame increases more than twice.

Improved ultra-fine coal cleaning with oscillatory and intermittent air supply

JUNYU WANG

The generation of high quality ultra-fine coal in Australia keeps increasing. However, the cleaning efficiency of this fraction of coal is limited by current bubble generation techniques. The aim of this study is thus to improve the separation efficiency of ultra-fine coal by applying oscillatory and intermittent air supply to the system. Results showed that oscillatory air supply resulted in the generation of smaller bubbles and larger amounts of bubbles, and that intermittent air flow led to a wider bubble size distribution. Also, flotation results showed that the introduction of the former air flow pattern led to a slight increase in concentrate yield, while the latter resulted in 25% decrease in frother dosage.

Effect of carbon chain length of organic salts on the thermodynamic stability of methane hydrate

YUAN SU

This study presents the phase equilibrium conditions for methane (CH4) hydrate with one of the following five organic ammonium salts differing in carbon chain length: tetramethylammonium bromide (TMAB), tetraethylammonium bromide (TEAB), tetrapropylammonium bromide (TPrAB), tetrabutylammonium bromide (TBAB), and tetrapentylammonium bromide (TPeAB). The hydrate phase equilibrium measurements were conducted for a temperature range of 279.41 to 291.85 K and pressure range of 4.79 to 14.32 MPa using the step-heating pressure search method. The addition of TBAB or TPeAB shifts the phase equilibria of the semiclathrate hydrates (SCHs) of CH4 to a lower

pressure/higher temperature zone.At a given dosage, TBAB consistently outperformed TPeAB in thermodynamically promoting methane hydrate formation. TMAB, TEAB or TPrAB slightly shifts the phase equilibrium conditions to a higher pressure/lower temperature region, which is comparable to NaCl inhibition effect.

Understanding the separation of sphalerite (ZnS) by flotation using air bubbles

MAJID EJTEMAEI The chemical features of sphalerite surface in the presence of pyrite and CuSO4 (used to activate the sphalerite flotation) were investigated using X-ray photoelectron spectroscopic (XPS) and high-speed video microscopy (HSVM). The XPS results showed that the copper activation is an ion exchange mechanism with CuS layer formed on the mineral surface. They also showed S2- surface species on the pyrite surface was oxidized by the reduction of Cu(II) to Cu(I) during the Cu activation. The HSVM studies showed the formation of hydrophobic species on copper activated sphalerite that could be elemental sulfur, while this was not the case for pyrite activation by Cu. This study will lead to a better understanding of sphalerite flotation, saving millions of dollars for the mining industry by

using less CuSO4.

Galvanic interaction between gold and pyrite in the presence of oxygen YANGYANG HUAI The separation of gold bearing pyrite from blocky pyrite has long been an issue in sulphide mineral flotation industry. Although there are observations that pyrite is more oxidised when coupled with gold in ores, the fundamental knowledge of the gold and pyrite interaction in this area is lacking. In this study, the existence and enhancement of the galvanic interaction between gold and pyrite with oxygen was investigated using electrochemical techniques to guide the separation of gold and pyrite in industry. An intensive reduction peak appearing at -200mV on cyclic voltammetry curve indicated that an additional elemental or metallic deficient sulphur layer formed on the pyrite surface during oxygen enhanced galvanic interaction with gold, while only slight change showing in the ambient condition. A relative slow kinetics after galvanic interaction was confirmed by Tafel polarization and Electrochemical Impedance spectroscopy measurements.

The interfacial reactions between Ga based alloys and common substrates in microelectronics

SHIQIAN LIU

Ga based alloys have attracted great attention due to their unique properties which enable them to be used as a bonding material in various microelectronic interconnections. Its non-toxic nature, low melting temperature, and high vapour pressure make it a better substitute for mercury in many liquid metal applications.

Advanced Manufacturing Techniques

This study aims to develop a better understanding of interfacial reactions between Ga based alloys and common substrates in microelectronics. This presentation covers the results of my first year of research, including preparation of candidate alloys, microstructure analysis and the crystallography and physical properties of the intermetallics obtained by optical and electron microscopy and synchrotron X-ray diffraction experiments.

Mechanisms of Surface Stability in Al-Zn Coated Steel MATTHEW GEAR

Thin coatings of Al-Zn based alloys are frequently applied to mild steel to provide protection from corrosion. There are economic and environmental advantages associated with minimising the thickness of these surface coatings. Achieving a uniform thin stable coating in continuous production processes requires a deep understanding of the relationship between process variables and alloy composition. This research, performed in collaboration with numerous partners of the ARC Research Hub for Australian Steel Manufacturing, will use a variety of advanced techniques to understand the fundamental mechanisms influencing surface quality in the coating process. This presentation covers the results of my first year of research, including thermal analysis, fluid properties, and synchrotron work.

Transient Liquid Phase High Temperature of Sn-Cu alloys for Pb-free Solder Applications

FLORA SOMIDIN

Transient liquid phase processing (TLP) typically exploits the fact that interdiffusion between liquid metal and an adjacent solid phase will result in the formation of an intermediate solid phase of a higher melting point. This research will investigate the use of transient phase liquid processing to create lead-free solders for use at relatively high temperatures. The Sn-Cu alloy solder system will be used to create a TLP solder joint on Cu susbtrate. This presentation covers the results of my first year of research, including literature survey, preparation of candidate alloys, microstructure analysis by optical and electron microscopy work.

Development of High-Temperature Sn-Cu Soldering Alloys

SYEDA MEHREEN

With growing technological advances coupled with increasing complexity and miniaturization of electronic components, the electronic manufacturing and assembly sector is a key role player influencing the ever rising international demand for electronic goods. Environmental regulations placed on lead as a soldering constituent has restricted its use in electronic assembly manufacturing and has further driven R&D of Pb-free soldering alloys. Sn-Cu alloys have generated interest as potential candidates for high-temperature soldering applications, as they are economically feasible & environmentally safe. However, the challenge arises from the formation of a brittle intermetallic compound (IMC), produced as a result of a peritectic reaction that occurs in the Sn-Cu system. This research aims to develop a reliable Sn-Cu soldering alloy for high-temperature applications, whereby the brittle IMC is suppressed. By microalloying additional elements with Sn-Cu, promising results have been achieved.

Molecular dynamics simulation of diffusion of gases in polymer membranes

RAVI CHANDRA DUTTA

A combination of Grand Canonical MonteCarlo simulations and Molecular Dynamics has been employed in order to explore the structure of polymers and to compute the solubility and diffusivity of gases in polymer membranes. We report the structural properties of the polymers at different temperatures and pressures based on the radial distribution function and void distribution analysis. We also report the adsorption isotherms of gases on different polymers. Solubility of gases in polymers was systematically investigated based on free energy calculations and examined the temperature dependency on solubility. We report the self-diffusivity, corrected diffusivity and transport diffusivity of gases in different polymer systems at different temperatures and pressures. The permeability of the gases and hence the selectivity has been reported in different polymer systems.

Characterisation of bulldozer pivot push for autonomous operation

RICHARD HENSEL

Pivot push is a strip mining overburden removal process in which bulldozers systematically remove the material above a coal seam by pushing into an adjacent void. There are various methods by which pivot push may be implemented, but a lack of clear evidence to suggest which is most efficient for a given situation. As pivot push comes under autonomous operation, mission planning decisions must be based on a more thoroughly defined cost. We seek to develop a simulation framework to determine the cost of each strategy over a range of situations. The work presented relates to an experimental study conducted to inform the development of this framework. Data was gathered from a suite of sensors on board a bulldozer while at work in a production strip. It was found that strategies in which material is pushed to an edge and allowed to spoil naturally at the angle of repose were more efficient than those in which material is directly placed at its final location.

Determining turbulent spot initiation rates from transition lengths in hypersonic boundary layers

SREEKANTH RAGHUNATH

Experimental evidence indicates that boundary layers in hypersonic flows transition from being laminar to turbulent via the mechanism of formation of turbulent spots. Turbulent spots have been detected either using surface heat transfer gauge signals or pressure traces or visualized using high-speed schlieren techniques. However, it is not possible at present to predict the spot initiation rates in hypersonic transitional flows. As a first step towards developing a model to predict the turbulent spot initiation rates in hypersonic transitional flows, a methodology adopted to estimate the turbulent spot initiation rate from experimental hypersonic transitional mean heat transfer data is demonstrated for several test cases. The distribution of intermittency and mean heat transfer rate in the transition zone, re-constructed based on the

estimated turbulent spot initiation rates, are compared with the corresponding experimentally determined distributions, and found to agree well.

XRD characterization study of Starch-based material crystallization behaviour

ZHIXUE LIU

Starch is a promising biodegradable polymer which is renewable and cheap. Crystallization of starch-based materials is one of the main factors which affects their final properties, such as mechanical strength, dielectric properties and appearance. Thermal processing of starch leads to the destruction of natural crystalline structures and induces new crystalline structures. Crystalline structures of starch-based materials plasticized by glycerol and different types of ionic liquids studied by XRD will be discussed together with the effect on their resulting properties.

Effect of oxidation degree on the flotation behaviour of oxidized coal ZIYONG CHANG

In this work, the effect of coal oxidation on the flotation behaviour was studied. Flotation tests indicated that coal floatability decreased significantly after coal oxidation. XPS was used to assess the extent of coal oxidation and the percentage of oxidized carbon was developed as an oxidation index. The critical oxidation degree was found for coal oxidation, above which the flotation of oxidized coal was completely depressed. Both surface hydrophobicity and surface charge were found to be influenced by coal oxidation degree, and both of them contributed to the loss of coal floatability. Extended DLVO theory was applied to account for the role of surface hydrophobicity and surface charge in the existence of critical oxidation degree.

Application of Fibre Optic Sensing techniques for Rock Mass Deformation in Underground Mines

HONGKUI GONG

Roof deterioration in underground mines may lead to roof fall that can cause fatalities, injuries and interruptions to the mining production. The drawback is the complexity of conventional electrical and electromechanical sensing systems and practical issues in their installation in underground coal mines. Over the past decade, fibre optic techniques, which are considered as intrinsically safe sensing instruments, have proved to be successful in structural monitoring for a wide range of civil engineering applications such as bridges, dams and underground tunnels. For mining industry, deeper understanding of the mining-induced deformation field is the motivation for the development of mine-scale deformation monitoring techniques. This presentation will provide a review of the application of fibre optic sensing techniques for rock mass deformation in underground mines, focused on the technology advancement and the limitations.

Developing a model to enhance learner-learner interactions in virtual learning environments MOHSEN DOKHANCHI

The characteristics of online learner population are changing. They are not willing to go on receiving information passively with minimal interaction. Online collaborative learning is the answer for these changes. Online communication is one of the key players in this domain. There is a need to examine how learning in such contexts actually occurs. Technology provides solid platform for online communication, however it does not guarantee successful learning. It is essential to measure the quality of online communication and identify the factors that influence peer learning in online study groups. Number of participants are more than the total number of students posting in a discussion forum. Understanding issues that influence participation are essential for effectively designing online discussions. Structure and Rheological Properties of Constituent Polysaccharides from Plantago Ovata Seed Mucilage LONG YU

The mucilage envelope is a key structure implicated in seed dispersal and germination. In this study, we report the discovery that upon hydration of Plantago ovata seeds, mucilage is excreted as a multi-layered structure around the seed. Three constituent polysaccharide fractions have been isolated from the corresponding layers. All three polysaccharides are comb-like polymers, predominantly consisting of the xylose backbone densely decorated by arabinose and/or xylose side chains. The fraction from the outermost layer (L1) is rich in galacturonic acid residues behave like viscoelastic liquid , while the inner layers, which are neutral fractions L2 and L3, are classified as gels (G’>G”). L3 gel is more fluid-like and melts upon increase in temperature at 41°C, while L2 gel is more solid-like and remains a gel even when heated to 85°C. We also discover that different molecular architecture of these complex heteroxylans is responsible for their different rheological properties.

The relationship between upper-airway resistance and breath transition time. DWAYNE MANN

Introduction: People are known to extend the duty cycle of the inspiratory period of breathing patterns during periods of sleep where the upper-airway resistance is increased (i.e. in obstructive sleep apnoea, OSA). However, in normal tidal breathing during sleep, frequent periods of low or no airflow (transition period) appear between breaths. We hypothesised that the transition time between breaths represents a reserve capacity in which the inspiratory period can extend during periods of high upper-airway resistance to maintain ventilation. Methods: The transition time was calculated during 104 normal and 295 high resistance periods in 20 OSA patients. Results: The mean transition time was lower in normal resistance breathing than in high resistance breathing (0.817±0.279 to 0.567±0.187 seconds, p < 0.001, mean±SD). Discussion: Humans are able to compensate for high upper airway resistance by extending the inspiratory duty cycle and reducing the transition period between breaths.

Designing Smart Communities

Control Synthesis for Complex Motions KIANOOSH SOLTANI NAVEH

Motion control for multi-body systems remains a difficult mathematical and engineering problem. The difficulty arises from the nonlinearities and constraints. Model Predictive Control (MPC), which relies on repeatedly solving constrained optimization problems, has been considered as a promising approach to motion control. However, our background research revealed that robustness, feasibility and optimality issues pose an obstacle. A study of human motor control and learning, revealed that natural examples do not rely on instantaneous optimization, rather they rely on learning and combining primitive motion behaviors. Inspired by these findings, we present a number of hypotheses to study whether a paradigm based on the mixture of primitive behaviors can be formulated and realized. Pattern recognition for electronic noses SANAD SANAD

Nanotechnology and chemical sensing industry is growing fast nowadays, higher competition with increasing demands of reliable chemical processes is resulting in production of small, fast, cheap, and reproducible chemical sensors. This technology has become a basic enabling technology in machine olfaction (Electronic Noses) with many applications in environmental monitoring, health industry, safety, security, and industrial hygiene. Despite their reputation, their practical values are affected by their poor stability making them very vulnerable to drift and noise. These vulnerabilities can be resolved using periodic recalibration which in turn increases their cost significantly and make them overly complex. The primary objective of this research is to investigate, propose, and implement an effective and adaptive framework for gas sensor pattern recognition. DESIGNING COMMUNITIES OF FAITH : Brisbane Church Building Design in the 1960s LISA DAUNT

The twentieth century was a time of massive upheaval in the intellectual, theological and architectural spheres of society. This prompted a re-evaluation of Church building design. As a result, in Brisbane, as elsewhere, new approaches to suburban church building design emerged in the 1960s. The results were widely diverging as architects, denominations and church communities held different opinions on how the church building could be adapted to modern times. Analysing three exemplary Brisbane churches, this presentation will demonstrate how each design considered the local, South East Queensland context – both in terms of climate and community, the presentation will thus highlight how these churches sought to improve the built environment by casting a fine mesh of religious infrastructures across Brisbane’s suburban fabric. The Development of Optimised Operating Conditions for the X3R Reflected Shock Tunnel SAMUEL STENNETT

The Defence Science and Technology Group require a large-scale high-speed flow facility, capable of providing longer test times over larger models than current facilities in Australia, in order to allow experimental testing of their latest HIFIRE 8 scramjet. A proposal was made to modify The University of Queensland’s large ‘X3’ expansion tube to a reflected shock tunnel configuration ‘X3R’ in order to supply these long test times. My research topic is to

develop optimised operating conditions for ‘X3R’, in order to produce the desired long duration test conditions, while overcoming challenges relating to the facility’s unique geometry compared to other reflected shock tunnels. Structural and Impact Performance of Thin-Walled Folded Sandwich Structures for Modular Resilient Infrastructure YOUSEF AL-QARYOUTI

This project aims to develop folded sandwich structures: a new type of modular structural form that retains the streamlined construction of existing prefabricated systems and can additionally be rapidly fabricated with non specialist and low-cost manufacturing plant. Such a system would generate new technological and design options for community reconstruction efforts following infrastructure loss from extreme events and so directly addresses Strategic Research Priority 1, living in a changing environment . The project investigations will also develop structural engineering knowledge related to the new form and in the emerging field of origami-inspired engineering design. Nonlinear Analysis of Soil-Foundation-Superstructure Interaction under Dynamic Actions with Discrete Element Method AHMAD DEHGHANPOOR SICHANI

The phenomenon of soil-structure interaction can be briefly described as follows: during dynamic actions, soil deforms under the influence of the incident waves and carries dynamically with it the foundation and the supported structure. The phenomenon of soil-structure interaction can be briefly described as follows: during dynamic actions, soil deforms under the influence of the incident waves and carries dynamically with it the foundation and the supported structure. In turn, the induced motion of the superstructure generates inertial forces which result in dynamic stresses at the foundation that are transmitted into the supporting soil. Smoothed Particle Hydrodynamics for investigating of flood impacts on failure behaviour of an embankment under action of an overburden load MAZIAR GHOLAMI KORZANI

The structural and post-failure behaviours of embankments are of paramount significant due to extreme weather events. This study focuses on impacts of soil-water interacting forces, as a consequence of floods, and overburden loads due to service or emergency loads under the operating condition. Smoothed Particle Hydrodynamics (SPH) method was employed as a replacement to conventional numerical schemes. In general, this paper aims to provide a robust modelling tool and to enhance the SPH method for geotechnical engineering investigations. To achieve this goal, a novel approach is proposed in SPH to deal with soil-water interacting forces. Afterwards, the suggested scheme was validated intensively by various problems involving dry soil, water and the both. Finally, the developed tool was used to investigate the main problem. Results show that the capacity of an embankment to withhold a load on its crest as well as its post-failure behaviour are significantly dependent on flow conditions. Development of Disposable Aircraft for Atmospheric Data Collection ALEXANDER MACINTOSH

Small unmanned aircraft fitted with a guidance system and sensor payload have the potential to expand the scope and precision of atmospheric data collection beyond what is currently possible with existing devices, such as weather balloons and conventional aircraft. Additional data serves to improve weather forecasting and environmental monitoring capabilities. The challenge is to develop a design which is both functionally and economically competitive. In this presentation, a critical review of related research will be given to expose the knowledge gaps, followed by a summary of current and future work to address these gaps and the associated challenges. Efficient Schemes for Similarity-aware Refinement of Queries

ABDULLAH ALBARRAK

Interactive data exploration platforms are becoming increasingly popular. Typically, users without prior knowledge of data interact with these platforms in an exploratory manner hoping they might retrieve the results they are looking for. One way to explore large-volume data is by posing exploratory queries. Though, when a query fails, i.e., returns undesired results, users will have to undertake a frustrating trial-and-error process to refine their queries, until a desired result is attained. This data exploration process, however, is growing rather difficult as the underlying data is typically of large-volume and high-dimensionality. We address this challenge by proposing innovative schemes for efficient Similarity-Aware Refinement of Queries which aim to balance the trade-off between satisfying the constraints on the query's result and the similarity constraints imposed on the refined query to maximize its overall benefit to the end user. Revival of Vernacular Village in China--A Preliminary Investigation of the Rammed Earth Folk Houses in the Mountainous Area of Northern Fujian Province XIAOXIN ZHAO

In recent years, the rapid pace of urbanization in China has had significant large-scale impacts on rural areas are now confronted with challenges. A a new “vernacular frenzy” sweeping around villages in China. Based on this context, the character of vernacular architecture and the construction principles and process that using natural material from the local area is the subject of paper. In 2005, Chinese government proposed the “beautiful village” project, in order to improve the happiness and life satisfaction of people in rural areas. In 2013, the author participated in surveying the local village named Yangyuan Village, Zhenghe Count by interviewing villagers and craftsmen, photographing and computer modeling. In conclusion, using recyclable material and its construction principles, should be an eco-friendly and renewable way to the sustainable development of villages.

Modelling Influence of a Bus Rapid Transit System on Urban Land Use and Transport Accessibility: A Case Study of Brisbane SVITLANA PYROHOVA

Land use is an important aspect of government policies and regulation for activities and urban growth management. While most of previous studies on Bus Rapid Transit (BRT) and land use focused on the investigation of BRT influence on land price or value capitalization, the research on changes in land types is still evolving. This study will establish a methodology for identifying and quantifying factors that contribute to changes in land use via statistical analysis. With consideration of the level of integration between public transport and surrounding land uses, accessibility measures will be estimated. Longitudinal survey

data will be used to determine individuals’ choices of residential location in relation to a preferable way to travel. This will allow us to avoid bringing bias into the model and will contribute to policy making for such areas. On this basis, a new model will be developed to forecast future spatial development patterns within the alignment of busway corridors.

Marginal abatement cost curves for water-related greenhouse gas management should consider water end use

KA LEUNG LAM

Greenhouse gas management in urban water systems typically focus on optimising within the direct system boundary of water utilities. This work develops a marginal abatement cost curve of water-related greenhouse gas management from a city perspective and compares this with that from the water utility perspective. Results show that the cost-effective greenhouse gas abatement potential from a city perspective is far more significant than that from a utility perspective. In some cases, for similar capital cost, if regional water planners invested in water end use options instead of utility options, a greater abatement potential could be achieved.

Sustainable development through integrated urban water systems - The multiple use of iron

MARIO JR REBOSURA

Considering high iron concentration in drinking water sludge (in the case iron salts are used as coagulants), could impact the downstream processes in the sewer system and wastewater treatment. In sewers it has the potential to be beneficially reused in sewer networks for sulphide control. In wastewater treatment plants, chemical removal of phosphate in the biological water treatment processes as well as in the anaerobic digester sulphide is precipitated producing H2S-free biogas. This study investigated the effects of sewer discharge of iron containing DW sludge on the physical, chemical and biological processes occurring in the sewer systems and in various sub units of wastewater treatment. Lab-scale simulations will be performed similar to actual systems with a sewer reactor, primary settler, sequencing batch reactor (SBR), sludge thickener and the anaerobic digester (AD).

Synergistic Interaction between Anaerobic Ammonium Oxidizing Bacteria and Denitrifying Anaerobic Methane Oxidizing Archaea

JIAOYANG PU

Nitrogen imbalance which results from anthropic activities leads to environmental issues.So it is important to understand related biochemical processes better,like Anaerobic Ammonium Oxidation(Anammox)and Denitrifying Anaerobic Methane Oxidation(DAMO)processes. Usually Anammox bacteria utilize NH4+ and NO2- while DAMO archaea reduce NO3- to NO2- with CH4 as electron donor.Here,NO3- or NO2- with NH4+ and CH4 were supplied to 2 reactors with same biomass,respectively.From the results different pathways were shown. In the reactor with NO3-,NO3- was reduced to NO2-

Water

by DAMO archaea and the produced NO2- was used by Anammox bacteria.But in the reactor with NO2-, Anammox process occurred with the production of N2 and NO3-.Then DAMO archaea participated in the anaerobic NO3- reduction.FISH analysis also indicated DAMO archaea and Anammox bacteria could grow together well under different conditions. It could be inferred DAMO and Anammox processes might occur synergistically in natural environments.

Determining the response of nitrifiers to the antimicrobial agent free nitrous acid. ANDREW LALOO

Free nitrous acid (FNA) acts as a biocidal agent and exerts a stronger effect on the nitrite oxidising bacteria (NOB) than on ammonia oxidising bacteria (AOB) resulting in FNA being effectively applied to selectively inhibit NOB in wastewater treatment processes. However, to date there is little understanding of the mechanisms and inhibitory effects of FNA. Herein, we study the effect of FNA on a nitrifying community in an 11L-activated sludge sequencing batch reactor, operated with periodic exposure to FNA. Metagenomic sequencing and metaproteomic analyses identified over 500 Nitrosomonas (AOB) proteins among them were those identified those for Vitamin B12 transport, Ton B dependent transporters, CO2 fixation and biotin-associated proteins were abundant in the high FNA conditions. A thorough metaproteome analysis is underway to reveal the reasons for the higher tolerance of AOB to NOB.

Biotransformation of the antibiotic trimethoprim in anaerobic sewers

LUDWIKA NIERADZIK

Due to human consumption, the presence of the antibiotic trimethoprim in domestic wastewater has been reported frequently. 80 % of the excreted trimethoprim consists of the unmetabolised parent compound, which is discharged into sewers before entering downstream sewage treatment plants. In this work, the anaerobic biotransformation products of trimethoprim in sewers were investigated using lab-scale experiments in sewer biofilm reactors, which previously showed to mimic anaerobic sewer processes. It was shown that up to 78 ± 1 % of the parent compound were removed after a retention time of 8 h. Further experiments at 12 mg/L during 13 days revealed the formation of at least 2 anaerobic biotransformation products, namely P276 and P238. As only the parent trimethoprim is being monitored during wastewater treatment, the presence of these previously not identified biotransformation products may pose a previously unknown hazard for the receiving waters of treatment plants effluents.

Anaerobic co-digestion CATHERINE MACINTOSH

Anaerobic Digestion (AD) is a process that is widely applied in industry to treat organic waste and produce biogas. Recently there has been interest in Anaerobic co-digestion (AcoD) involving the simultaneous anaerobic digestion of two or more waste-streams. Whilst AcoD offers strong potential for enhanced methane production, incompatible substrates or overdosing of co-substrates can lead to process failure. Dosage strategies therefore need to be managed to avoid process risks. This presentation will detail research examining the co-digestion of glycerol with three different base-substrates: pig manure; sewage sludge; and cattle slaughterhouse wastewater.Preliminary experimental results

suggests that base substrate characteristics as well as the microbial community can influence the maximum co-substrate dose.

Electrofermentation As a Tool to boost the anoxic metabolism of Pseudomonas putida

BIN LAI

Pseudomonas putida is a promising host for the bioproduction of chemicals, but its industrial applications are significantly limited by its obligate aerobic character. In this presentation, I will share our work to empower the anoxic metabolism of Pseudomonas putida by bioelectrochemical system (BES). Intracellular energy and redox equivalents were tested to study the effect of electric redox power on cell status. Overall, this study, for the first time, proved the principle that a BES-driven bioconversion of glucose can be achieved for a wild-type obligate aerobe. The yield of 2-keto-gluconate from glucose is over 90%, and the productivity is positively correlated with the redox power from BES. This study proposed a non-growth bioconversion process and confirmed it in high yields, high purity and also delivering the necessary metabolic energy for cell maintenance from redox power of BES.

Acid mine drainage treatment using Bio-Electrochemical technologies

GUILLERMO POZO

In this work, a novel two-stage bio-electrochemical process was devised and tested at lab scale for the removal of sulfate, salinity and acidity from acid mine drainage treatment. first stage cell (bio-electrochemical) hosts the biocathode working electrode, where autotrophic sulfate reduction takes place, which may involve direct electron transfer by sulfate reducing microorganisms or indirect (H2-mediated) sulfate reduction. In a second stage (electrochemical cell), elemental sulfur is generated by electrochemical anodic oxidation of the produced sulfide, which is subsequently recovered, while simultaneously removing sulfide toxicity on the SRBs.

A novel decentralized grey-water treatment system based on combined adsorption and electrochemical oxidation in a 3D reactor ELISABET ANDRES GARCIA

Decentralized water production (i.e. small scale plants to treat wastewater in-situ) and the use of reclaimed water provides an excellent opportunity for sustainable, reliable and cost effective growing demand, increasing the robustness of water supply networks. Electrochemical systems present several promising characteristics to be implemented, and are comparable with other technologies in cost and efficiency. The performance of these systems can be substantially improved by the use of a bed material inside the reactor. The aim of this project is to develop a water treatment system based on adsorption and electrochemical oxidation for the treatment of greywater. Combination of both processes have demonstrated a better performance than their operation individually and superposed.

Effect of Chloride ions on Electrochemically-Generated Sulfate Radicals for the Removal of Organic Matter

ALI FARHAT

Electrochemical techniques for the degradation of organic matter are being widely investigated, where sulfate and chloride radicals are produced at the anode and both play a major role in the electrooxidation of organic matter. Active chloride radicals' presence produces chlorinated organic and inorganic undesired contaminants. Since chloride and sulfate ions are ubiquitous in most water and wastewater systems, it is crucial to investigate the effect of chloride and sulfate ions on the quality of the treated water. The removal of resorcinol was studied in the presence of different concentrations of chloride and sulfate ions. Results show that the presence of sulfate accomplishes higher removal rates of the organic matter, produces less chlorinated organic compounds by 84%, yet generates higher concentrations of chlorate and perchlorate.

Nitrogen recovery from hydrolysed urine through microbial electroconcentration JOHANNES JERMAKKA

Microbial fuel cells (MFC) enable moderate electricity production from waste water streams, but feasible practical applications are still lacking. A novel chemicals free concept for nitrogen recovery for fertilizer use from human urine as a solid is presented, in which a microbial fuel cell is combined with electrodialytic unit. Urine is highly promising substrate for electrochemical treatment, as it is highly buffered, highly conductive and contains high concentrations of ammonium nitrogen. The concept efficiency and viability depends on several study questions forming the structure of this PhD. Firstly, a method of forming a solid nitrogen compound through electroconcentration is investigated. Secondly, the cathode oxidation rate is a bottleneck and a previously unpublished oxygen delivery method is researched. Thirdly, hydrolysed urine is a difficult environment for a bioanode, and different anodic setups are regarded. Finally, this thesis aims to a working application.

Smart nutrient recovery systems based on starch hydrogels: Sustainable material solutions for wastewater industries

SAMIRA SIYAMAK

Hydrogels are a novel class of functional biopolymers with the ability to dynamically respond to external stimuli. Their tailorablity differentiates them from other polymeric materials, making them excellent candidates for the design of smart devices 1. Amongst them, starch hydrogels have recently been identified as having potential to be successfully employed in a variety of unconventional applications such as recovery of nutrient from wastewater 2. The existing starch hydrogels are currently only found in the laboratory and have limited functionality as nutrient recovery systems 3. Therefore, the development of affordable and smart nutrient recovery systems based on starch hydrogels is a propitious approach for reducing the environmental impact of industrial pollution 4. Our vision is to develop a novel processing method based on reactive extrusion, designed for industrial scale production of this smart hydrogels for the treatment of industrial wastewater.

The Future Insight of the FO-AnMBR Implementation in Wastewater Treatment NUR HAFIZAH AB HAMID

Water scarcity becomes one of the major concerns nowadays and research has been done progressively in determining the best technologies for water treatment. The development of membrane filtration provides a new insight, especially for the wastewater treatment field and forward osmosis (FO) is currently gaining the industrial attention not only because of its well

rejecting performance, but also due to its lower operating cost. The implementation of forward osmosis-anaerobic membrane bioreactor (FO-AnMBR) is expected to be the future leading technology, however, more research need to be done especially in determining the optimum design to reduce the major limitation of membrane filtration; the membrane fouling.

Performance of inorganic carbon membranes for oil-water separation

SITI NUREHAN ABD JALIL

Water pollution caused by oily wastewater to the environment is a serious global concern. Although the technologies for oily wastewater treatment have been in constant development and update in the last 30-40 years, the major drawbacks are high energy demand, operating cost and chemical consumption. The application of inorganic membrane filtration, especially carbon-based membranes, can offer several advantages namely: (i) size-exclusion of oil droplets from emulsions, (ii) no chemical addition is required, (iii) stable in aggressive environments and (iv) easy maintenance and operation. This project focuses on changing the pore size and surface property of carbon membranes to achieve high water flux, high oil rejection and reduced membrane fouling. Water permeation and oil rejection results of 12 kg m-2 h-1 and 98% respectively, were found to be promising. Also, the degree of reversible fouling via the recovery of membrane performance after cleaning in cycling experiment is reported.

Feasibility of PV and battery energy storage based EV charging in different charging stations MD SHARIFUL ISLAM

Depending on charging locations and business interest, EV charging facilities can be classified into Commercial Charging (CC), Business Charging (BC), and Home Charging (HC). Diurnal load distribution in these EV charging facilities can be dissimilar on the account of different customers’ behavior. Therefore, these charging facilities will put forth different degrees of impacts on the grid. A portion of the impacts can be reduced through onsite deployment of PV and battery energy storage system (BESS). However, the extent of reduction depends on wide range of factors such as costs, correlation between EV load profile and PV generation profile etc. Thus, the objective of this work is to find out which one of these three charging facilities is technically and economically feasible for PV and BESS based EV charging station.

Structural and Impact Performance of Thin-Walled Folded Sandwich Structures for Modular Resilient Infrastructure

YOUSEF AL-QARYOUTI

This project aims to develop folded sandwich structures: a new type of modular structural form that retains the streamlined construction of existing prefabricated systems and can additionally be rapidly fabricated with non specialist and low-cost manufacturing plant. Such a system would generate new technological and design options for community reconstruction efforts following infrastructure loss from extreme events and so directly

Poster

addresses Strategic Research Priority 1, living in a changing environment. The project investigations will also develop structural engineering knowledge related to the new form and in the emerging field of origami-inspired engineering design.

Modelling Park-and-ride user behaviour in South East Queensland

BIBHUTI SHARMA

This paper presents a discrete choice model for the park-and-ride (PNR) lot choice in South East Queensland (SEQ). Many PNR lots in SEQ are underutilized while some have parking that spills over into nearby streets. To understand what makes users choose one PNR lot versus another, we conduct a user survey in eighteen PNR lots of SEQ. Questionnaire surveys are distributed to PNR users while they are in the platform waiting for the public transport service. Altogether 442 questionnaires are returned back. The result from the survey shades light on several issues like amenities that users consider important, reasons why user consider particular PNR lot versus another, reason why user consider using PNR versus driving alone and so on. These results will be modelled using discrete choice modelling technique. The model is likely to give a detail understanding on the factors that influence users’ PNR choice.

Energy use for water provision in cities KA LEUNG LAM

Energy demand for urban water supply is emerging as a significant issue. This work undertakes a multi-city time-series quantification and analysis of the energy use for water provision in 30 cities from 13 countries, and illustrates their performance with a new time-based water-energy profiling approach. High variation in per capita energy use for water provision exists among the cities (14 - 346 kWh/person/year). Data on potential influencing factors are used to explore how and why the energy use differs across the cities. In addition, the general reduction trends (11-30%) between 2000 and 2014, and some lessons learned are discussed.

Investigation of Power System Frequency Response in Presence of High Solar PV Generation

NAHID-AL MASOOD

At present, installed capacity of solar photovoltaic (PV) in South Australian network is around 600 MW. Within next few years, this capacity may exceed 1,000 MW. Unlike synchronous generators, PV sources do not provide frequency control functions such as inertia and governor response. Moreover, many distributed PV systems in South Australia may have a default under-frequency protection setting, which could be higher than the under frequency load shedding threshold. Hence, a moderate load-generation imbalance may cause a massive secondary PV trip, which results in an unacceptable low frequency. Consequently, customers may face unexpected load shedding, which affects network service standard.

Potential of nanoparticles to prevent clay swelling in coal seam gas reservoirs. ARCHANA PATEL

We evaluated the effectiveness of six commercial nanoparticles (NPs) to mitigate swelling of smectite clays in coal bed methane (CBM) reservoirs. The commonly used clay stabilisation chemical in Queensland CBM wells is potassium chloride (KCl) brine, but CBM

operators report the effectiveness of KCl is limited to a short time once production from the reservoir commences. Thus, an objective of this study is to develop alternative or complementary clay stabilisation technologies that can continue to work after several days of gas and water production.

Swelling tests were made by a visual method (American Society for Testing and Material’s ASTM D5890-11) model formation water (pH 5 to 9, TDS 2550 mg/L and 9000 mg/L as NaCl). We observed that, in typical model formation water prepared according to Queensland CBM reservoir water chemistry, the silica NPs show the most promising clay stabilisation potential. Apart from this, Silica and Magnesium oxide both showed potential to prevent clay swelling in formation water with addition of 2%KCl. There are few published reports on the use of NPs to control clay swelling in petroleum reservoirs. This paper presents new experimental data and insights into the fundamental mechanisms by which NPs may act to stabilise the swelling of clays in an unconventional gas reservoir.

Effect of hydrogen peroxide oxidation of carbon nanotube additives on the microstructure of pitch-derived activated carbon foam

SHUAI GAO

Carbon foams with high porosity, large surface area, good thermal stability and mechanical strength have potential applications in energy storage, catalyst supports, and adsorption. Filler particles such as carbon nanotubes (CNT) can be used to control the foaming process and to enhance the mechanical properties of the foam. In this study, CNT-reinforced activated carbons foams were prepared by low-pressure foaming and carbonization of pretreated tar-pitch mixed with hydrogen peroxide treated CNT in ethanol. Sonication of the pitch + CNT mixture was another variable investigated. Potassium hydroxide was added as a chemical activation agent to the pitch + CNT mixture. The BET surface area of the treated-CNT carbon foam was 1541 m2/g. Our results show that treatment of CNTs can improve their effectiveness as filler particles of carbon foams derived from pitch.

An overview of Existing In-Sewer Physical, Chemical and Biological Processes Modelling Approaches

SOHAN SHRESTHA

In-sewer wastewater including sewer structure are subjected to significant changes in composition during conveyance due to various complex and dynamic in-sewer physical, chemical and biological processes. Extensive research works regarding modelling approaches had been undertaken since last 70 years for understanding and predicting H2S/sulfide build-up, sewer pH, biofilm formation, concrete corrosion, natural or forced ventilation, pollutant transport, recovery of available heat energy from sewer system including in-sewer sediment processes. Modelling approaches of complex biochemical transformation of organic matter caused by diverse microorganisms present in slime layer under aerobic, anoxic and anaerobic conditions are depicted. However, development of a state-of-an-art mathematical sewer model is still lacking. To this notion, some research gaps requisite for the further advancement of in-sewer process modelling are also incorporated.

Comprehensive CES Planning based on the Cost Benefit Analysis JUNAINAH SARDI

This paper proposes a methodology to determine the optimal location and capacity of a single Community Energy Storage (CES) by considering all possible benefits of CES. The

benefits include energy arbitrage, peaking power generation, energy losses reduction, Transmission and Distribution (T&D) system upgrade deferral, reduction in CO2 emission and VAR support. Moreover, a comprehensive cost benefit analysis is conducted to identify the optimal Net Present Value (NPV) of profit, Discounted Payback Period (DPP) and Benefit to Cost ratio (BCR) of CES investment using the current, 2025 and 2035 CES’s capital costs. Numerical results presented show that the proposed CES planning strategy is able to identify the optimal location and size of CES unit for maximizing the NPV of the profit. In addition, some interesting findings are also discussed in the paper

Removal of Persistent Organic Contaminants by Electrochemically-generated Sulfate Radicals and Persulfate ALI FARHAT

Electrochemical advanced oxidation processes (EAOPs), especially with boron-doped diamond (BDD) anodes, can effectively oxidize toxic trace organic contaminants such as pharmaceuticals and herbicides which are inefficiently removed in conventional wastewater treatment systems. Persulfate is reported to be produced in sulfate-based BDD-EAOPs; however, no mechanism of its interaction in such systems have been outlined. This work addresses the potential formation of SO4•- radicals through the step of formation of persulfate as well as its decomposition and investigates the contribution of such radicals to the degradation of the toxic organics. Results show faster degradation rates and complete removal of the toxic organics in sulfates compared to nitrates, where higher rates were reported at higher sulfate concentration and current density. Chemical oxidation of these organics showed no oxidation power of pure persulfate, holding SO4•- radicals responsible for the faster oxidation rates.

Cathodic biofilm activates electrode surface and achieves efficient autotrophic sulfate reduction

GUILLERMO POZO

Electron transfer pathways occurring in autotrophic sulfate-reducing biocathodes are still unknown. Here, we studied the biocathode operation under different ratios of sulfate and CO2 as electron acceptors, using an integrated approach comprising (i) electrochemical tools, including chronoamperometry and linear sweep voltammetry; (ii) liquid phase chemical analysis; and (iii) real-time off-gas measurement by mass spectrometry. The key message is that the enriched biofilm had role in activating the electrode surface for hydrogen evolution reaction (HER), putatively via surface immobilisation of metallic and proteinaceous materials, suggesting that the biofilm was able to modify the electrode surface towards more efficient HER and achieved efficient autotrophic sulfate reduction.

Decentralized Grey-water Treatment System Based On Electrochemical Oxidation

ELISABET ANDRES GARCIA

Due to climate change and population growth experienced today globally, appropriate water management becomes a priority. Decentralized water production and the use of reclaimed water provides an excellent opportunity for sustainable, reliable and cost effective growing demand for safe water quality by complementing centralized water supply systems. The objective of this project is the development of low-cost and low-energy-consuming water treatment system, based on combined adsorption and electrochemical oxidation, capable to recover the grey-water in situ for fit-for-purpose water production. The results obtained from the preliminary experiments show that the main driver for the removal of organic matter, close to 90%, is the adsorption onto activated carbon (AC). However when a current

is applied through the material, electrochemical regeneration of the bed is achieved extending the saturation of the AC in the system and oxidising the pollutants present in the water.

Stochastic Generation and Transmission Planning Considering Future Renewable and Gas Opportunities in Queensland, Australia

JULIANA NUNES

This paper assesses long term electricity planning under uncertain load growth, gas price, renewable production and new technologies’ investment costs for the state of Queensland, Australia in 2030. A stochastic programming approach is mathematically formulated to decide which technology to be built, while determining its capacity and location. Additionally, new investments in transmission lines are examined. The problem is modeled as a mixed-integer linear programming approach and is solved using four distinct cases to assess the impact of carbon costs, the renewable energy target and retirement of coal-based generation.

A review of flow pattern maps to predict gas-liquid flow regimes in vertical pipes and annuli BENJAMIN PO-CHIEH WU

Two-phase gas-liquid flows in vertical configurations are complicated phenomena that are utilised in the petroleum and nuclear energy industries amongst others. These flows manifest themselves in a sequence of flow regimes that are intrinsically linked to the flow mechanisms of the system. Previous attempts at empirical solutions for predicting these flow regimes have considered only limited data sets which result in highly case specific predictions. This review summarises all published experimental results concerning two-phase flow regimes in vertical pipe and annuli allowing for a more universally applicable interpretation. Collating these results also permits for the identification of those parameters that most significantly affect the flow regimes, and validation of published two-phase flow models. The author also investigates the possibility of a non-dimensional solution capable of accounting for various parameters but results are inconclusive.

Core Analysis and Pulsed Arc Electrohydraulic Discharge (PAED) Stimulation of Coal Seam Interburden

FEI REN

The interburden of coal seam reservoirs mainly consists of mud, silt, clay and organic matter. Its potential, as a viable methane source, has not yet been well researched or developed, comparing with that of sandstone, coal or shale. The reason is that interburden formations possess some intrinsic properties, such as malleability, compressibility, impermeability and more importantly low gas content, which impede their commercial production utilizing existing technologies and methodologies. However, there is an obvious advantage in mudstones that their greater thickness, when compared to thin coal measures, leads to a considerable total gas volume. Based on this fact, this research will address a novel stimulation methodology, i.e., pulsed arc electrohydraulic discharge, for the exploitation of carbonaceous mudstones and siltstones interbedded between coal measures.

Condition Monitoring and Fault Detection in Solar PV System

AMIT DHOKE

Condition monitoring of solar PV plants is essential for fault detection and diagnosis. This research will contribute to developing a system for monitoring large solar PV plants. A mathematical model of PV module will be developed that will take into account wind and temperature effects on PV output in addition to the Global Horizontal Irradiance (GHI). Using the module level model, PV plant model will be developed. The PV plant model will be used for fault diagnosis.The model will be developed in Matlab to demonstrate the detection of partial shading and degradation faults in PV systems. The method to be used for fault detection will be based on the string level monitoring with the measurements of operating voltage and current. The simulation and experimental results will be presented to validate the proposed PV plant model and the fault detection method.