Improving combustion stability in sugar factory boilers

Reliable operation of a sugar factory boiler station is essential for efficient and timely processing of the cane supply. Sugar factory boilers have to contend with changes in fuel quality caused by variations in performance of the extraction station, different cane varieties and associated agronomic factors along with fluctuations in factory steam demand. These variations can affect the stability of combustion in boiler furnaces leading to reductions in boiler steam output and large furnace pressure fluctuations that can cause serious damage. This paper investigates the causes of unstable combustion, discusses aspects of boiler design that make a boiler more susceptible to unstable combustion and uses modelling to evaluate different options for improving combustion stability.

The experience of learning in “The Cube” : Queensland University of Technology’s giant interactive multimedia environment

In this paper we report findings of the first phase of an investigation, which explored the experience of learning amongst high-level managers, project leaders and visitors in QUT’s “Cube”. “The Cube” is a giant, interactive, multi-media display; an award-winning configuration that hosts several interactive projects. The research team worked with three groups of participants to understand the relationship between a) the learning experiences that were intended in the establishment phase; b) the learning experiences that were enacted through the design and implementation of specific projects; and c) the lived experiences of learning of visitors interacting with the system. We adopted phenomenography as a research approach, to understand variation in people’s understandings and lived experiences of learning in this environment. The project was conducted within the first twelve months of The Cube being open to visitors.

Shortages of rural mental health professionals

This study presents a conceptual model of the supply and demand for mental health professionals. It uses national data to profile differences in the supply of mental health professionals in different types of rural and urban areas. It contrasts the availability of general health and mental health professionals. It examines shortage areas identified in 2000 and their related community characteristics. Because of the absence of data on a national level to describe many types of mental health professionals state licensure data for one state were used to show the volume and distribution of these practitioners. To improve rural mental health service delivery it will be necessary to implement system changes to promote the increased availability, competency, and support of rural health professionals. Copyright 2003, Elsevier Science (USA). All rights reserved.

Measuring the biases in self-reported disability status : Evidence from aggregate data

Self-reported health status measures are generally used to analyse Social Security Disability Insurance's (SSDI) application and award decisions as well as the relationship between its generosity and labour force participation. Due to endogeneity and measurement error, the use of self-reported health and disability indicators as explanatory variables in economic models is problematic. We employ county-level aggregate data, instrumental variables and spatial econometric techniques to analyse the determinants of variation in SSDI rates and explicitly account for the endogeneity and measurement error of the self-reported disability measure. Two surprising results are found. First, it is shown that measurement error is the dominating source of the bias and that the main source of measurement error is sampling error. Second, results suggest that there may be synergies for applying for SSDI when the disabled population is larger. © 2011 Taylor & Francis.

A QUM partnership approach to regulating biosimilars in Australia

Despite the realisation of the potential implications from biosimilars is relatively recent, much has already been written about raising the awareness of differences between biosimilars and originating/ reference listed (innovator) pharmaceuticals. The European Medicines Agency has led the global charge in regulating biosimilars. Regardless of sufficient similarities across international regulations, differences do exist across jurisdictions. The consideration of regulating biosimilars demands a congruent approach across all stages: pre-registration (Australian copyright protection, patent, international obligations), registration (confidential information, international regulators, safety and efficacy), post-registration (Pharmaceutical Benefit Scheme, prescriber and dispenser awareness). Our National Medicines Policy could provide the necessary congruent framework and function for national and international regulation of biosimilars. The Policy concedes that pharmaceuticals will be affected by financial policies and trade considerations, international treaty obligations, industrial policies, education policies and the need for public-private partnerships.

Management of a high grade pan stage schedule to reduce the steam consumption

MOST PAN stages in Australian factories use only five or six batch pans for the high grade massecuite production and operate these in a fairly rigid repeating production schedule. It is common that some of the pans are of large dropping capacity e.g. 150 to 240 t. Because of the relatively small number and large sizes of the pans, steam consumption varies widely through the schedule, often by ±30% about the mean value. Large fluctuations in steam consumption have implications for the steam generation/condensate management of the factory and the evaporators when bleed vapour is used. One of the objectives of a project to develop a supervisory control system for a pan stage is to (a) reduce the average steam consumption and (b) reduce the variation in the steam consumption. The operation of each of the high grade pans within the schedule at Macknade Mill was analysed to determine the idle (or buffer) time, time allocations for essential but unproductive operations (e.g. pan turn round, charging, slow ramping up of steam rates on pan start etc.), and productive time i.e. the time during boil-on of liquor and molasses feed. Empirical models were developed for each high grade pan on the stage to define the interdependence of the production rate and the evaporation rate for the different phases of each pan’s cycle. The data were analysed in a spreadsheet model to try to reduce and smooth the total steam consumption. This paper reports on the methodology developed in the model and the results of the investigations for the pan stage at Macknade Mill. It was found that the operation of the schedule severely restricted the ability to reduce the average steam consumption and smooth the steam flows. While longer cycle times provide increased flexibility the steam consumption profile was changed only slightly. The ability to cut massecuite on the run among pans, or the use of a high grade seed vessel, would assist in reducing the average steam consumption and the magnitude of the variations in steam flow.

Capital cost model for Robert evaporators

ROBERT EVAPORATORS in Australian sugar factories are traditionally constructed with 44.45 mm outside diameter stainless steel tubes of ~2 m length for all stages of evaporation. There are a few vessels with longer tubes (up to 2.8 m) and smaller and larger diameters (38.1 and 50.8 mm). Queensland University of Technology is undertaking a study to investigate the heat transfer performance of tubes of different lengths and diameters for the whole range of process conditions typically encountered in the evaporator set. Incorporation of these results into practical evaporator designs requires an understanding of the cost implications for constructing evaporator vessels with calandrias having tubes of different dimensions. Cost savings are expected for tubes of smaller diameter and longer length in terms of material, labour and installation costs in the factory. However these savings must be considered in terms of the heat transfer area requirements for the evaporation duty, which will likely be a function of the tube dimensions. In this paper a capital cost model is described which provides a relative cost of constructing and installing Robert evaporators of the same heating surface area but with different tube dimensions. Evaporators of 2000, 3000, 4000 and 5000 m2 are investigated. This model will be used in conjunction with the heat transfer efficiency data (when available) to determine the optimum tube dimensions for a new evaporator at a specified evaporation duty. Consideration is also given to other factors such as juice residence time (and implications for sucrose degradation and control) and droplet de-entrainment in evaporators of different tube dimensions.

Experiences with control of evaporators using extensive vapour bleeding

FOR SUGAR factories with cogeneration plants major changes to the process stations have been undertaken to reduce the consumption of exhaust steam from the turbines and maximise the generated power. In many cases the process steam consumption has been reduced from greater than 52% on cane to ~40% on cane. The main changes have been to install additional evaporation area at the front of the set, operate the pan stages on vapour from No 1 or No 2 effects and undertake juice heating using vapour bleed from evaporators as far down the set as the penultimate stage. Operationally, one of the main challenges has been to develop a control system for the evaporators that addresses the objectives of juice processing rate (throughput) and steam economy, while producing syrup consistently at the required brix and providing an adequate and consistent vapour pressure for the pan stage operations. The cyclic demand for vapour by batch pans causes process disturbances through the evaporator set and these must be regulated in an effective manner to satisfy the above list of objectives for the evaporator station. The impact of the cyclic pan stage vapour demand has been modelled to define the impact on juice rate, steam economy, syrup brix and head space pressures in the evaporators. Experiences with the control schemes used at Pioneer and Rocky Point Mills are discussed. For each factory the paper provides information on (a) the control system used, the philosophy behind the control system and experiences in reaching the current system for control (b) the performance of the control system to handle the disturbances imposed by the pan stage and operate within other constraints of the factory (c) deficiencies in the current system and plans for further improvements. Other processing changes to boost the performance of the evaporators are also discussed.

Information Experience : Approaches to Theory and Practice

"The German word for experience - Erlebnis - the experience of the life, to live through something - underpins this book: making visible scholarly opportunities for richer and deeper contextualizations and examinations of the lived-world experiences of people in everyday contexts as they be, do and become." (Ross Todd, Preface). Information experience is a burgeoning area of research and still unfolding as an explicit research and practice theme. This book is therefore very timely as it distils the reflections of researchers and practitioners from various disciplines, with interests ranging across information, knowledge, user experience, design and education. They cast a fresh analytical eye on information experience, whilst approaching the idea from diverse perspectives. Information Experience brings together current thinking about the idea of information experience to help form discourse around it and establish a conceptual foundation for taking the idea forward. It therefore "provides a number of theoretical lenses for examining people's information worlds in more holistic and dynamic ways." (Todd, Preface)

Research in Early Childhood Education for Sustainability : International Perspectives and Provocations

Sustainability is a global issue that urgently needs addressing, the most serious consequences of which concern children and future generations. This insightful research text tackles one of the most significant contemporary issues of our times – the nexus between society and environment – and how early childhood education can contribute to sustainable living. By offering international and multidisciplinary research perspectives on Early Childhood Education for Sustainability, each chapter explores and investigates the complex topic of sustainability and its relationship to early childhood education. A particular emphasis that runs through this text is young children as empowered citizens, capable of both contributing to and creating change for sustainability. The chapter authors work from, or are aligned with, a transformative education paradigm that suggests the socio-constructivist frameworks currently underpinning Early Childhood Education require reframing in light of the social transformations necessary to address humanity’s unsustainable, unjust and unhealthy living patterns. This research text is designed to be provocative and challenging; in so doing it seeks to encourage exploration of current understandings about Early Childhood Education for Sustainability, offers new dimensions for more deeply informed practice, and proposes avenues for further research in this field.

Academic librarians' varying experiences of archives : a phenomenographic study

This article reports on a study investigating academic librarians' varying experiences of archives in order to promote understanding and communication among librarians and archivists. A qualitative, phenomenographic approach was adopted for the study. Three different ways of experiencing archives were identified from analysis of interviews. Archives may be experienced by academic librarians as 1) a place which protects collections; 2) resources to be used in accomplishing tasks such as teaching, research, or outreach; or 3) manifestations of politics. The third way of experiencing archives is the most complex, incorporating both the other experiences. The results of this study may help librarians, especially academic librarians, and archivists communicate more clearly on joint projects involving archival collections thereby enabling more collaboration.

Improving boiler performance with modified boiler control systems

For timely processing of the crop, sugar factories need boiler stations that can reliably produce steam when fired with fuel of variable quality. The control systems installed on most sugar factory boilers have changed little in the last thirty years and in some cases the default control system response to changes in fuel and/or fuel quality is not correct and operator intervention is required to prevent factory stoppages or reductions in crushing rate caused by poor combustion. Some factories have recently modified their boiler control systems for improved combustion performance and reduced maintenance costs. This paper describes testing carried out to evaluate some of these control system modifications and identifies boiler control system changes that can be applied more widely in the sugar industry.

Information Experience : New Perspectives and Research Directions

In this closing chapter the editors review key themes that have emerged through the book. We recognize the varied and dynamic nature of information experience across multiple contexts, and present our own conceptualization of information experience. Finally, we consider possible future directions for information experience research.

Review and future options for computer modelling in the sugar industry

Computer modelling has been used extensively in some processes in the sugar industry to achieve significant gains. This paper reviews the investigations carried out over approximately the last twenty five years,including the successes but also areas where problems and delays have been encountered. In that time the capability of both hardware and software have increased dramatically. For some processes such as cane cleaning, cane billet preparation, and sugar drying, the application of computer modelling towards improved equipment design and operation has been quite limited. A particular problem has been the large number of particles and particle interactions in these applications, which, if modelled individually, is computationally very intensive. Despite the problems, some attempts have already been made and knowledge gained on tackling these issues. Even if the detailed modelling is wanting, a model can provide some useful insights into the processes. Some options to attack these more intensive problems include the use of commercial software packages, which are usually very robust and allow the addition of user-supplied subroutines to adapt the software to particular problems. Suppliers of such software usually charge a fee per CPU licence, which is often problematic for large problems that require the use of many CPUs. Another option to consider is using open source software that has been developed with the capability to access large parallel resources. Such software has the added advantage of access to the full internal coding. This paper identifies and discusses the detail of software options with the potential capability to achieve improvements in the sugar industry.

An orientation to early childhood education for sustainability and research : framing the text

This publication arose from the interests of the chapter authors, ‘a small group of thoughtful people’ almost all of whom participated in one or both Transnational Dialogues in Research in Early Childhood Education for Sustainability, held in Stavanger, Norway in 2010 and Brisbane, Australia in 2011 (Refer Appendix 1 for list of participants). These meetings were the first time that a critical mass of researchers from vastly different parts of the globe - Norway, Sweden, Australia and New Zealand at the inaugural meeting, with additional participants from Korea, Japan and Singapore attending the second - had come together to debate, discuss and share ideas about research and theory in the emerging field of Early Childhood Education for Sustainability (ECEfS. Some of the researchers who joined these Transnational Dialogues, had met serendipitously at earlier conferences and meetings, or corresponded via email, but many had never met face-to-face. Now a significant number are contributing authors in this text. It is a testament to these researchers’ interest in this agenda that they mostly self-funded their travel and other costs to attend the Transnational Dialogues research meetings. While most chapter authors come from the field of early childhood education, a few are more aligned with education for sustainability/environmental education, while a much smaller number are already working at the intersection of early childhood education and education for sustainability. What we share as a group is a range of perspectives and orientations to research and to the research focus at the heart of this book - young children and their actual and potential capabilities as agents of change for sustainability. As researchers, regardless of experience and perspectives, participants knew they had something extra to offer - their expertise as researchers - providing scholarly insights into the work of practitioners, applying critically reflective lenses to curricula, pedagogies and assumptions, testing of ideas and theories, and presenting a sense for where ECEfS might fit or, indeed, go beyond norms and orthodoxies. This is a text, then, for both researchers and those whose primary interests lie in daily interactions with children, families and communities.