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Social Innovation and Deep Institutional Innovation for Sustainability and Human Development

The engineering graduate of today will engage in a career which will span the middle of the twenty-first century, and beyond. They will work in a world which is increasingly more complex and uncertain than at any time before. This will require an integrated combination of technical knowledge and transferable skills and values, to a greater extent than ever before. This paper highlights the need for the contemporary engineering graduate to develop capacity to deal with increased uncertainty and complexity. It seeks to demonstrate how this can be achieved through developing key graduate attributes. These attributes may be promoted through suitable exposure to progressively more open-ended problems and activities across the programme. A number of exemplars are provided from two European chemical engineering programmes.

A vital first step for regional energy transitions is to develop an understanding of the current energy balance and related carbon dioxide emissions. However, there is a lack of clarity within existing literature on how best to determine a complete regional energy balance including industry, residential, services, agriculture, and transport sectors. This paper identifies four key limitations in the literature: over-reliance on simple population-based proportioning, a narrow focus on building energy, subsequent omission of transport energy in the majority of studies and a lack of transparency in a significant number of studies. This paper proposes a novel conceptual framework to address these gaps using a combination of local energy usage indicators and national unit energy consumption statistics. The authors apply this multi-dimensional approach to a rural case study region, carefully examining the range of energy usage indicators in each sector before selecting the most suitable. The results quantitatively demonstrate the value of this approach, with the final energy demand in some sectors varying by as much as double or threefold compared with a population weighting. Focusing on the socio-economic drivers of energy demand in this manner provides useful insights into the local context that defines the energy system.

Metaphor, along with narrative and other linguistic devices such as myth, fable, parable, and allegory, enables us to make sense of the world around us and shape how we think and act individually and collectively in relation to society and the natural world. The chapter considers the properties of metaphors and how they can promote or curtail action towards transformative change in the direction of sustainability. The notion of transformation itself is examined and is taken to represent profound changes in the ways we understand economy, society, and the place of technology. Indeed, it calls for a recalibration of the popular imagination – and this is where metaphor, myth, and fable have such a vital role to play. As an introduction to the book, the chapter explains the structure of the volume comprising four parts each of which explore different dimensions of metaphor from the ways it shapes our relationship with science and technology to the rich terrain of psychoanalysis, creativity, and artistic practice. Each of the subsequent 13 chapters are briefly described and demonstrate the spirit of transdisciplinary collaboration which informs their quite different analyses, but which share a commitment to sustainability representing an authentic societal and environmental flourishing.

The present moment of deep transition, as well as being a time of danger, presents an opportunity for positive renewal. This paper develops a model of deep institutional innovation at times of historic change such as the present and outlines a research agenda aimed at initiating a holistic assessment of the main foundational institutions in society and re-imagining them in ways that will allow them to fulfill their basic ethical and effectiveness functions. Such a fundamental critique and re-imaging, the paper argues, is essential if global challenges are to be mitigated and resolved.

Biopharmaceuticals manufacturing is a critical component of the modern healthcare system, with emerging new treatments composed of increasingly complex biomolecules offering solutions to chronic and debilitating disorders. While this sector continues to grow, it strongly exhibits "boom-to-bust" performance which threatens its long-term viability. Future trends within the industry indicate a shift towards continuous production systems using single use technologies that raises sustainability issues, yet research in this area is sparse and lacks consideration of the complex interactions between environmental, social and economic concerns. The authors outline a sustainability-focused vision and propose opportunities for research to aid the development of a more integrated approach that would enhance the sustainability of the industry.

This paper presents a systematic review of participatory methods used in energy system modelling and planning. It draws on a compiled database of fifty-nine studies at a local, regional, and national level detailing analysis on full energy systems down to sectors, modes, and single technologies. The initial aim of the paper is to consolidate and present this growing body of literature, providing a clear understanding of which stakeholder groups have been engaged and what methods have been used to link stakeholder engagement with quantitative analysis. On from this, the progress to date in democratising key decision-making processes is discussed, reflecting on the benefits and challenges of a participatory approach, as well as highlighting gaps within the current body of literature. During the review, two differing spatial levels at subnational (cities, municipalities, or regions) and national scale emerged as separate groups for analysis. A clear distinction between the two groups was the motivation for involving stakeholders. At a subnational level, researchers hoping to build local capacity to bring about real-world change engaged with community representatives, whereas national level studies concerned with generating more impactful energy policy measures involved industry, policymaking, and academic experts. One key finding from the review was that only ten out of the fifty-nine studies reviewed noted some form of collaboration with non-academic stakeholders, and moreover 36% of studies involved just a single interaction with participants. This indicates a lack of progress to date in process democratisation within energy system modelling and planning research.

The absorption of steam bubbles in a hot aqueous solution of Lithium Bromide is a key process that occurs in the absorber vessel of a heat transformer system. During the condensation process, their size and shape changes dynamically with time as they rise up through the column of liquid. An understanding of the factors that control the vertical upwards motion of the bubbles is necessary to enable proper design of such units. However, the exact vertical displacement of a bubble moving through a liquid is difficult to predict and becomes much more complex if the bubble is simultaneously collapsing. In this paper, the displacement of steam bubbles collapsing in a concentrated aqueous lithium bromide solution (LiBr–H2O) has been quantified experimentally. A simple kinetic model predicting the vertical displacement as a function of time was then developed from elementary force–balance considerations. A key feature of the system is the large variability in the motion of the bubbles arising from extreme fluctuations in their size and shape. Bubble dynamic morphology was modelled with stochastic techniques and the output from this was used in the kinetic model to predict dispersion in bubble displacement with time. While the uncertainty predicted by the stochastic model is shown to be less than that observed experimentally, it nonetheless highlights the importance of this random behaviour during the design of such an absorption column.

Evaporation maps are a convenient way of representing the dynamic composition of evaporating liquid mixtures. Specifically, these maps represent the residual composition of evaporating ternary non-ideal mixtures over the full range of composition, and are analogous to the commonly used residue curve maps of simple distillation processes. The evaporation process considered here involves gas-phase limited evaporation from a liquid or wetted-solid surface, over which a gas flows at known conditions. Evaporation may occur into a pure inert gas, or into one pre-loaded with a known fraction of one or more of the ternary components. The model developed here uses an exact solution to the Maxwell–Stefan equations for mass transfer in the gas film, with a lumped approach applied to the liquid phase. Solutions to the evaporation model take the form of trajectories in temperature–composition space, which are then projected onto a ternary diagram to form the map. Efficient Newton-based methods are used to calculate the composition and temperature of pseudo-azeotropes in the mixture, and to calculate the wet-bulb temperature at a given composition. A numerical continuation method is used for tracking the bifurcations which occur in the evaporation maps, where the composition of one component of the pre-loaded gas is the bifurcation parameter. The bifurcation diagrams can in principle be used to determine the required gas composition to produce a specific terminal pseudo-azeotrope composition. Provided the gas-phase limited assumption applies, such analysis is applicable to applications such as drying of solvent-based coatings and tray-drying of granulated pharmaceutical products.

Vapour absorption heat transformers are thermodynamic cycles which are capable of upgrading the temperature of waste heat energy using only negligible quantities of electrical energy. Although marked as a future technology by the IEA (International Energy Agency), as being important for energy utilization in the 21st century, industrial applications of heat transformers are still very limited. This paper presents a comprehensive review of heat transformer research over the past two decades. Emphasis is placed upon optimisation studies, alternate cycle configurations, working fluids comparisons and industrial application case studies.

This study evaluated the personal carbon footprints of two lecturers who have western life-styles living in the global north and would also consider themselves as being environmentally and sustainability conscious individuals. Not surprisingly, both had relatively high carbon footprints that were similar to the average in their country of residence at double the global average. A major reflection from the study is that it is difficult for (even environmentally conscious) individuals to drastically reduce their carbon footprints when they live and participate in a society that has a high carbon footprint. Change in complex adaptive holarchic systems is recursive and thus there is a need for concomitant societal change in order to facilitate further the individuals’ capacity to achieve the radical reductions in their carbon footprints required to realise a sustainable society operating within biophysical limits.

Education represents a key intervention point in encouraging the emergence of a professional engineering ethos informed by a sustainability ethic. In terms of establishing an appropriate relationship between sustainability and education, many would contend that incorporating sustainability as merely add-on material to already overcrowded curricula is insufficient. Instead sustainability should actually be a leading principle for curricula. Traditional reductionist models of engineering education seek to extinguish context and uncertainty and reduce complexity across socio-economic and ecological domains. They therefore constitute a wholly inadequate response to the need for fit-for-purpose, twenty-first century graduates required to address broader sustainability issues. This paper presents research from an undergraduate module at University College Cork, Ireland. The module is aimed at developing students' conceptions of complexity, uncertainty, risk, context and ethics as foundational bases for productively engaging with sustainability. The paper also highlights some problematic issues.

Absorption heat transformers are thermodynamic cycles that are capable of recycling waste heat energy by increasing its temperature. One of the most important unit operations in a heat transformer is the exothermic absorption of water vapour into a solution of choice at a higher temperature. Bubble columns are potentially an efficient means of achieving this. An experimental analysis is conducted which examines the absorption of single steam bubbles into a concentrated aqueous lithium bromide solution. The bubbles are tracked using a high speed camera, and their rate of absorption is modelled using a simple ordinary differential equation model. Accurate model predictions are obtained when oscillating bubble Nusselt and the Sherwood number correlations are utilised. The proposed model is capable of describing 96% of the observed experimental variability. Very large mass transfer coefficients of approximately 0.0012 m/s are obtained, which is higher than any previously reported values used in heat transformer absorber design.

Heat transformers are closed cycle thermodynamic systems which allow waste heat energy to be recycled by increasing its temperature. TAHTs (Triple stage heat transformers) are capable of increasing the temperature of supplied heat by up to ∼140 °C. This paper attempts to analyse the industrial attractiveness of such cycles by conducting a case study on the potential installation of a TAHT in a small Irish oil refinery, examining various different natural gas price scenarios. The choice of waste heat energy being recycled is shown to be pivotal to the success or failure of the installation. TAHTs are demonstrated to show most benefits when applied to waste heat streams with large quantities of latent heat. The usage of more efficient and cost effective equipment instead of conventional shell and tube heat exchangers within the system dramatically increases the potential economic return from the heat transformer. At the present gas price, the capital cost of (conventional) equipment is too high to make this investment financially attractive for the current industrial example, with excessive payback periods predicted. However a return to natural gas price levels observed in 2008 and 2009 would make the unit economically viable.

In this paper, a rigorous multi-dimensional analysis is conducted upon a triple absorption heat transformer (TAHT) using the working fluids water and lithium bromide (LiBr). A full factorial design is created which determines the most influential factors affecting the system’s coefficient of performance (COP), exergetic coefficient of performance (ECOP), flow ratio (FR) and total exergy destruction (ED). The aim is to draw general conclusions which may be adopted into any such TAHT cycle and not simply be specific to any one scenario. Accordingly the paper analyses the position of each variable across its thermodynamically available range instead of the traditional selection of arbitrary temperatures. It is found that in general the condensation temperature and the pinch heat transfer gradient selected have the greatest effect, and that these should be minimised in all situations. There exist points of optimum for the temperatures of the two absorber–evaporators within the cycle, however the evaporation temperature has conflicting effects for different dependent variables, and must therefore be selected based on an economic analysis. The results of this study also show that the generator is the source of the largest exergy destruction in the cycle, followed by the two absorber–evaporators.

In a bulk chemical plant producing resins, a flashback from an incinerator through the vent system into the reactor hall occurred during commissioning of a newly installed vent header system. The original design of the vent header system was seriously flawed not being in line with current practice. Subsequently the vent header was re-designed into a rich/lean vent header system. This paper explores the reasons behind a number of incidents and near misses that occurred during both the commissioning of a vent header system and its recommissioning following system re-design. Furthermore, it reflects on some broader implications for approaches to safety around what can be recognised as complex socio-technical systems.

PurposeThis paper aims to present key findings from an inquiry into engineering accreditation and curricula renewal. The research attempted to ascertain conceptions of requisite sustainability themes among engineering academics and professionals. The paper also reflects on the potential role of professional engineering institutions (PEIs) in embedding sustainability through their programme accreditation guidelines and wider implications in terms of rapid curricula renewal.Design/methodology/approachThis research comprised an International Engineering Academic Workshop held during the 2010 International Symposium on Engineering Education in Ireland, on “accreditation and sustainable engineering”. This built on the findings of a literature review that was distributed prior to the workshop. Data collection included individual questionnaires administered during the workshop, and notes scribed by workshop participants.FindingsThe literature review highlighted a wide range of perspectives across and within engineering disciplines, regarding what sustainability/sustainable development (SD) themes should be incorporated into engineering curricula, and regarding language and terminology. This was also reflected in the workshop discussions. Notwithstanding this diversity, clusters of sustainability themes and priority considerations were distilled from the literature review and workshop. These related to resources, technology, values, ethics, inter‐ and intra‐generational equity, transdisciplinarity, and systems and complex thinking. Themes related to environmental and economic knowledge and skills received less attention by workshop participants than represented in the literature.Originality/valueThis paper provides an appreciation of the diversity of opinion regarding priority sustainability themes for engineering curricula, among a group of self‐selected engineering academics who have a common interest in education for SD. It also provides some insights and caveats on how these themes might be rapidly integrated into engineering curricula.

A macro-scale probabilistic model of dilute phase pneumatic transport is developed to analyse the dispersion in the velocity of conveyed particles and to predict their velocity statistics. Fluid drag force, proportional to the relative velocity between the particle and fluid, is taken to be the agent that causes particle motion in the axial direction. The basic premise of the approach is that dispersion in axial particle velocity is a result of subsidiary random motion in the radial direction through the fluid velocity field. Two causes are investigated for this radial motion; gravity and inter-particle collisions. As the local fluid velocity experienced by a particle thus continuously varies in an unpredictable fashion, then the associated drag force fluctuates as does the resulting particle velocity. The non-deterministic nature of the fluid velocity acting on the particle is captured by treating fluid velocity as a stochastic process whose description comes from combining knowledge of the flow field with the nature of the radial motion of the particle. This novel approach allows analytical expressions to be obtained for the mean and variance of particle velocity. The accuracy of these predictions was checked by numerical simulation and found to be good. The analysis demonstrates that dispersion in particle velocity is a function of the magnitude of dispersion in fluid velocity (a fluid property), on the inertial rate constant of the particle (a combined particle/fluid property) and the autoregressive parameter (a property reflecting the type of radial motion).

In this paper, the design of a triple absorption heat transformer (TAHT) using the working fluids water and lithium bromide is dissected and reassembled using heat exchange network modelling in order to determine the optimum number and locations of internal heat exchange units within the system. It is found that the conventional design of the TAHT does not employ heat exchangers effectively, and that thus by rearranging these units system COP may be increased by 11.7% while exergy destruction within the system (its irreversibility) can be reduced by 21%. Strategically adding an extra one or two heat exchangers increases the COP by 16.4% and 18.8% while decreasing exergy destruction by 28% and 31.5% respectively compared to a conventional TAHT design.

Quality by Design (QbD) considers both the critical product characteristics and the environmental variables to design an optimum packaging system. This study applied the QbD approach for packaging and shelf-life determination of Granola by i) determining the water vapour transmission rate (WVTR) of packaging films at different environmental conditions, ii) develop and validate a shelf-life model of packed granola breakfast product and iii) predict shelf-life of packed Granola. The WVTR of packaging films (BOPP and biodegradable films, i.e., NK, NM, N913) was measured according to a full factorial experimental design (32), i.e., 10, 30, 40 °C; 32.5 ± 0.5, 75.5 ± 0.5, 92.5 ± 3.5% RH, and a mathematical model was developed. Granola breakfast product was packed (using the mentioned materials and also a commercial packaging film-control), stored under accelerated conditions (38 °C and 90% RH) and assessed for moisture content (critical quality parameter). A shelf-life model was developed and validated for Granola describing the relationship of the food, packaging and environmental conditions, and shelf-life was inferred for normal storage conditions. The developed WVTR global model considering the dependency of temperature and relative humidity was found to fit the experimental data well (R2 > 0.914). Granola moisture gain was the lowest in BOPP package followed by biodegradable N913 package. The shelf-life for Granola under accelerated conditions ranged from 2 to 13 days depending on the packaging film, and under normal storage conditions (20 °C and 75% RH) was 271, 269, 90, and 33 days for BOPP, N913, NK and NM packages, respectively.

The present study examines the breakage of particulate granola produced by fluidised bed granulation during pneumatic conveying process. Granola was pneumatically conveyed in a purpose built conveying rig designed to mimic product conveying and packaging. Three different conveying rig configurations were employed: a straight pipe, a rig consisting two 45o bends and one with a 90o bend. Particle breakage increases with applied pressure drop, and a 90o bend pipe results in more attrition for all conveying velocities relative to other pipe geometry. In terms of the fluidised bed granulation, there was no single operating parameter that was deemed to have a significant effect on breakage during subsequent conveying. A simple power law breakage model based on process input parameters was developed to describe aggregate breakage during pneumatic conveying. © 2013 Curtin University of Technology and John Wiley & Sons, Ltd.

A macro-scale model of the breakage of particles at a 90° bend during dilute phase pneumatic transport is presented. Breakage results if the impact force between the particle and pipe bend exceeds the intrinsic strength of the particle. The latter is taken to be distributed according to the Weibull distribution. Impact force depends on impact velocity and this relationship is obtained by a two-phase structural model of the particle, based on the widely used Kelvin–Voigt model. The impact velocity is distributed as a result of a distribution in particle velocity and in impact angle, though the variability in the latter is shown to be the significant component. The results of the theoretical analysis are confirmed by Monte Carlo simulations. For infant formula agglomerates with typical dimensions, slightly less than 2% of the infant formula agglomerates are predicted to fail when conveyed through a simple system containing one 90° bend (radius of 0.8 m) at a maximum superficial velocity of 20 m/s.

This chapter outlines a vision of progress and sustainability encapsulated by a process approach to reality as elucidated by Heraclitus and bolstered by contemporary scientific understanding around irreducible complexity and ineliminable uncertainty. It seeks to demonstrate that a process-informed approach to progress and sustainability is required, one encapsulating a transdisciplinary approach and ethos, as a prerequisite for addressing issues emanating from an unsustainable societal construct. Popular conceptions of sustainability typically envisage it in terms of competing or overlapping requirements of respective economic, social and ecological domains. Dominant models and conceptions of sustainability emanate from and cohere with the dominant societal paradigm. Robert Ulanowicz, a systems ecologist with a background in chemical engineering has developed a quantitative model for ecological networks. This model represents a radical departure from the tradition of ecosystems modelling based on simulation. While Ulanowicz's quantitative model has been developed for and successfully applied to systems ecology, it carries far broader resonance.

Sustainability is a normative topic framed by disciplinary perspectives. This can be problematic as the tools that are used and applied to meta-problems and ‘grand challenges’ associated with societal (un)sustainability, and which may result in proposed ‘sustainable solutions’, are framed through the lens of the ‘object world’ disciplinarian. Traditional engineering education and practice has tended to frame problems in narrow techno-economic terms, often neglecting broader social, environmental, ethical and political issues; or what might be termed the social complexities of problems (Bucciarelli 2008; Mulder et al. 2012). This reductionist approach has sought to close down risk and uncertainty through deterministic modelling and design, resulting in frameworks/models which provide an air of misplaced confidence but which are incapable of accounting for (or recognising) unknowability, and can thus lead to behaviour which ironically, results in increased fragility, rather than promoting increased robustness or resilience. Researchers in the social sciences and humanities are inherently more comfortable and adept with dealing with complexity, uncertainty and unknowability. This paper is posited in this context, whereby chemical engineering and sociology students taking respective disciplinary sustainability/environmental modules were brought together to work on a common assignment dealing with some aspect of sustainability. This paper reflects on this collaborative exercise, including the experiences of the students themselves, alongside some challenges and successes. It concludes that transdisciplinary approaches to learning are not just desirable in addressing wicked and meta-problems when addressing challenges of (un)sustainability, but represent a sine qua non for building the social capacity in confronting these issues.

Infant formula is usually produced in an agglomerated powder form. These agglomerates are subjected to many transient forces following their manufacture. These can be difficult to quantify experimentally because of their small magnitudes and short durations. Numerical models have the potential to address this gap in the experimental data. The objective of the research described here was to calibrate a discrete element model for these agglomerates using experimental data obtained for quasi-static loading, and to use this model to study the mechanics of the particle response in detail. The Taguchi method was previously proposed as a viable calibration approach for discrete element models. In this work, the method was assessed for calibration of the model parameters (e.g., bond stiffnesses and strengths) considering three responses: the force at failure, strain at failure and agglomerate stiffness. The Weibull moduli for the simulation results and the experimental data were almost identical following calibration and the 37% characteristic stresses were similar. An analysis of the energy terms in the model provided useful insight into the model response. The bond energy and the normal force exerted on the platens were strongly correlated, and bond breakage events coincided with the highest energy dissipation rates.

This study involves comparing key quality parameters (size, textural) of commercially available breakfast cereal granola with product produced by high shear and fluidised bed granulation processes. Impeller rotational speed was found to be the single most important process parameter which influences granola physical and textural properties in the production of high shear granola. In a fluidised bed granulation process nozzle air pressure and binder spray rate were both found to affect aggregate quality attributes. Overall, the high shear granulation process led to larger, denser, less porous and stronger (less likely to break) aggregates compared with the fluidised bed process. Commercial granola samples were compared with the granola produced in this study and showed a large variation in terms of size and textural properties across the brands investigated. Depending in the type of granola required (for example, to be sold as a stand alone breakfast cereal or as accompaniment to yogurt) different manufacturing processes and process parameters may be recommended. The insights gained from this work can aid in developing processes for the production of granola or similar products to match with consumer and manufacture expectations and requirements.

PurposeThe purpose of this paper is to ascertain the engagement and response of students to the teaching of engineering ethics incorporating a macro ethical framework whereby sustainability is viewed as context to professional practice. This involves incorporating a broader conception of engineering than is typically applied in conventional teaching of engineering ethics.Design/methodology/approachA real life wicked problem case study assignment was developed. Students' understanding and practical application of the concepts were considered. A survey was conducted to gauge students' appreciation of the professional importance and their enjoyment of the subject matter.FindingsIt was found that students appreciate and enjoy a macro ethical sustainability informed approach, but find it more challenging to apply in practice.Practical implicationsThe paper demonstrates an approach to the teaching of engineering ethics using a practical example, which can help broaden engineers' self‐perceived role towards one where sustainability is context. It also shows how students can find such an approach to teaching ethics to be both enjoyable and relevant.Social implicationsEngineers educated to perceive the importance of engaging with macro ethical issues as part of professional practice will be significantly better placed to inform public and industry policy towards greater good and engage with other professional and expert groups.Originality/valueIn this paper, an approach to engineering ethics which diverges from the traditional is proposed. This can be of value to those involved in the teaching of engineering ethics, particularly those seeking to incorporate sustainability and other macro ethical issues.

In the fluidised bed granulation process the effect of nozzle air pressure and binder spray rate on key aggregate quality attributes were studied. The experimental results show that a decrease in nozzle air pressure leads to larger mean granule size. The combination of lowest nozzle air pressure and lowest binder spray rate results in granules with the highest levels of hardness and crispness. The combination of low nozzle air pressure and low binder spray rate results in the least distribution span. Granola hardness was affected by nozzle air pressure. Nozzle air pressure and binder spray rate did not have significant effect on crispness.

The operating performance of high purity water systems such as pharmaceutical Deionized and Water for Injection (DI/WFI) distribution systems can be difficult to analyse due to the highly variable demand that is drawn from these systems; a situation compounded by schedule and demand volume uncertainties. This work presents a stochastic model to simulate volume and schedule uncertainties of industrial size DI/WFI systems. The model utilises discrete-event simulation combined with the Monte Carlo method to calculate the demand profile of the distribution system and a continuous simulation to compute the variation of the level in the storage tank. It is shown that the model may be used to predict if an existing DI/WFI systems is capable of delivering water for a new process, for which historical data is lacking. The model is programmed in Excel 2003 and is available for download [1] as open software.

Granola is an aggregated cereal food product which can be used as a breakfast cereal or snack comprised of ingredients such as cereals, nuts and honey. A high shear mixer granulator was used to produce granola in a wet granulation process followed by oven drying. The aim was to investigate the effect of granulation parameters; impeller speed, binder addition rate and wet massing time on key granola physical properties. Experiments were carried out at impeller speeds of 150, 200 and 300 rpm during binder addition and wet massing. Binder addition rates of 0.22, 0.33 and 0.65 g s−1 and wet massing periods of 6, 9 and 12 min were applied respectively. The granola was then dried on an oven at 160 °C for 10 min. Granule size distribution and granule strength were measured using a digital image analyser and texture analyser respectively. Regarding the process variables, the agglomeration behaviour was found to vary greatly with impeller speed. Granules formed at low impeller speed were found to have low apparent density. The results enabled the optimal ranges of impeller speeds, liquid binder addition rate and the wet massing time to be established for this system, thereby aiding the manufacturing process in terms of controllability and reproducibility.

The objective of this paper is to investigate the relationship between the compositions of four typical infant formulae, the evolution of key quality characteristics during pneumatic conveying and the mechanical properties of individual agglomerates. Conveying experiments were conducted using a lab-scale rig. Four quality characteristics were measured before and after conveying: bulk density, volume mean diameter, wettability and percentage free fat. Relative breakages were calculated from particle size distributions. Uniaxial compression experiments were performed on individual agglomerates, giving forces and strains at failure and agglomerate stiffnesses. Coefficients of restitution of the agglomerates were obtained by video analyses of drop tests. The data indicate that bulk densities before conveying and the force and the strain of individual agglomerates at failure were related to the protein content. The force at failure and agglomerate stiffness were strongly correlated, and generally increased with increasing protein to fat ratio while the strain at failure decreased.

The present review discusses the attributes of granola breakfast cereal produced by wet granulation. Granola is an aggregated baked food product often eaten as a breakfast cereal containing natural ingredients such as oats, nuts and honey. Wet granulation is a unit operation where fine primary particulate materials (powders, grains etc.) agglomerate in the presence of a liquid binder to produce larger granules. High-shear granulation and fluidised bed granulation are the most common mode of wet granulation. Granulation prevents the segregation of co-agglomerated components, resulting in an improvement in content uniformity. In addition, the compression and dissolution characteristics, product attractiveness of the product are improved. The granulation process and operation conditions are discussed in detail and a case study employing granola production is presented.

The geometry and operating conditions of a pneumatic conveying rig for infant formula were varied according to an L18 orthogonal array, with the goal of minimising variations in four product quality characteristics: bulk density, volume mean diameter, particle density and wettability. A modular pneumatic conveying rig was fabricated from 316L stainless steel components. The factors that were varied in these experiments included mode of conveying, air velocity, number of rig passes, bend radii and vertical rig section length. A factorial analysis of variance showed that the mode of conveying, air velocity and number of passes had a statistically-significant effect on bulk density. The optimum settings to minimise variability were dense phase conveying with a 50 mm plug length, 960 mm vertical section, 3 m/s air velocity, 2 passes and 50 mm bend radii, assuming a linear model. The bulk density change at these optimum settings was negligible at 0.9%.

The operating performance of deionized and water for injection (DI/WFI) distribution systems can be difficult to analyse due to the highly variable demand that is drawn from these systems, a situation compounded by schedule uncertainties. This paper presents a fuzzy logic (FL) model of a typical DI/WFI system simulating schedule uncertainties in the opening and closing events of the offtake valves based on operator behaviour, e.g. tiredness of the operators. The model utilises discrete-event simulation to calculate the demand profile of the distribution system and a continuous simulation to compute the variation of the level in the storage tank. It is shown that the FL model may be useful in the design of new DI/WFI systems if little historical data are available.

This work presents a deterministic and a stochastic model for the simulation of industrial-size deionized water and water for injection (DI/WFI) systems. The objective of the simulations is to determine if additional DI/WFI demand from future production processes can be supported by an existing DI/WFI system. The models utilize discrete event simulation to compute the demand profile from the distribution system; they also use a continuous simulation to calculate the variation of the water level in the storage tank. Whereas the deterministic model ignores uncertainties, the stochastic model allows for both volume and schedule uncertainties. The Monte Carlo method is applied to solve the stochastic method. This paper compares the deterministic and stochastic models and shows that the deterministic model may be suitable for most applications and that the stochastic model should only be used if found necessary by the deterministic simulation. The models are programmed within Excel 2003 and are available for download as open public domain software (1), allowing for public modifications and improvements of the model. The proposed models may also be utilized to determine size or analyze the performance of other utilities, such as heat transfer media, drinking water, etc. LAY ABSTRACT: Water for injection (WFI) and other pharmaceutical water distribution systems are notoriously difficult to analyze analytically due to the highly dynamic variable demand that is drawn from these systems. Discrete event simulation may provide an answer where the typical engineering approach of utilizing a diversity factor fails. This paper develops an Excel based deterministic and stochastic model for a WFI system with the latter allowing for the modeling of offtake volume and schedule uncertainty. The paper also compares the deterministic and stochastic models and shows that the deterministic model may be suitable for most applications while the stochastic model should only be used if found necessary. The models are available for download as open public domain software allowing for modifications and improvements of the model.

Discrete element modelling (DEM) is commonly used for particle-scale modelling of granular or particulate materials. Creation of a DEM model requires the specification of a number of micro-structural parameters, including the particle contact stiffness and the interparticle friction. These parameters cannot easily be measured in the laboratory or directly related to measurable, physical material parameters. Therefore, a calibration process is typically used to select the values for use in simulations of physical systems. This paper proposes optimising the DEM calibration process by applying the Taguchi method to analyse the influence of the input parameters on the simulated response of powder agglomerates. The agglomerates were generated in both two and three dimensions by bonding disks and spheres together using parallel bonds. The mechanical response of each agglomerate was measured in a uniaxial compression test simulation where the particle was compressed quasi-statically between stiff, horizontal, frictionless platens. Using appropriate experimental designs revealed the most important parameters to consider for successful calibration of the 2D and 3D models. By analysing the interactive effects, it was also shown that the conventional calibration procedure using a “one at a time” analysis of the parameters is fundamentally erroneous. The predictive ability of this approach was confirmed with further simulations in both 2D and 3D. This demonstrates that a judicious strategy for application of Taguchi principles can provide a sound and effective calibration procedure.

Granola is a baked aggregated food product which serves as a breakfast cereal or snack consisting of oats, cereals, nuts and honey. Particle breakage of aggregated granola can occur during conveying as product is transferred as part of the production process on its way to packaging. Such breakage occurs as a result of particle–particle and particle–wall collisions with the conveying equipment. In this work, a population balance model is developed to describe the breakage of granola as it is conveyed through a pneumatic conveying pipeline rig. The model incorporates the influence of conveying pressure, exposure time and pipeline geometry, and is also related to parameters associated with aggregate formation such as granulator mixing speed and time. The aggregates were formed in a high shear granulator subject to impeller agitation of 300 rpm for 9 min and were then propelled through a pipeline with a 90° bend at a number of different flow rates. Trials were carried out by applying compressed air at pressures of 200 kPa, 300 kPa and 400 kPa while the aggregates were subjected to a number of recycles through the rig. Modelling of this breakage process was achieved by constructing the population balance equations (PBEs) in the form of a mass balance on the granola aggregates. The solutions to the PBEs were obtained by means of discretization through the application of the Markov chain method. When the size range of the system was divided into an appropriate number of states, the Markov chain method for the population balances exhibited a reasonable approximation for predicting the particle size distribution (PSD) over time particularly during the initial rig cycles.

This paper focuses on two mechanical properties of granules, the coefficient of restitution and the strength, and analyzes their sensitivity to granule geometric parameters. The granules were obtained by fluid bed granulation of glass beads with an aqueous solution of PEG1500. Collisions were arranged between granules, and for granules against two glass plates, the first of them a non-covered plate, whereas the second was a plate covered with a thin film of PEG1500. The coefficient of restitution and the strength were measured for the granules, the former for individual particles also. In the case of individual glass particles the coefficient of restitution was around 0.61 for impacts on the flat glass, and 0.5 on the covered glass; for the granules, this parameter was around 0.44 for both situations and for collisions between granules. Sphericity, lacunarity and fractal dimension of the granule projected area, as well as the granule porosity, were determined. Granules giving the highest values for strength had the largest fractal dimension and the smallest lacunarity values regardless of their sphericity, porosity and coefficient of restitution.

Fluidised bed granulation (FBG) is a particle size enlargement technique which is widely employed in industry. Modelling of FBG is important in order to understand, control and optimise the process. In literature, population balance modelling (PBM) which is based on population balance equations (PBEs) is a common tool to model the processing of these particulate systems. However, the solution of PBEs is not straightforward except for relatively simple cases. In this paper, Markov chain simulation is introduced in order to model and analyse the particle size enlargement process in fluidised bed granulation where aggregation and breakage occur simultaneously. For the study, the size enlargement process of granules based on glass beads is examined. 10 g PEG (poly ethylene glycol) with 60% concentration is used as the binder for a 200 g batch. The results show that Markov chains are an efficient tool to model the granulation process. Particle size enlargement and the shape of particle size distributions during the granulation process have been estimated within acceptable errors.

Two fundamental properties of the particles are their velocity and consequent displacement versus time history during the granulation process. Knowledge of the particle velocity might supply much information about the sub-processes. In this paper, an analytical model of a solid particle motion in an internal re-circulatory fluidised bed unit is developed and validated against experimentally obtained data. The model predictions show good correspondence with the experimental results for the spherical particles. For the case of non-spherical granules, the agreement between the model and the experiments is not equally convincing but still adequate. Deux propri´´ fondamentales des particules sont la v´ elocit´

Analytical solution of population balance equations (PBEs) may be impossible except for some simple cases. In the literature there are a number of methods to solve PBEs including discrete methods, Monte Carlo simulation, and method of moments. In this paper, the Markov chain is presented as a discrete solution for a population balance equation of a breakage process for determining the particle size distribution (PSD) over time. The transition matrix P, which is the key operator of a Markov chain, is built using breakage equations. Thereafter, from calculating transition matrix, P, the particle size distribution of the system is easily evaluated using the Markov chain. According to simulation results, if the size range of the system is divided into a sufficient number of states and an appropriate transition time step was chosen, then results from the Markov chain are in agreement with the analytical solution of PBEs governed by the same breakage functions. In addition to theoretical illustration, the Marko...

Particle breakage due to fluid flow through various geometries can have a major influence on the performance of particle/fluid transport and separation processes. Whey protein precipitate dispersions were used as a case study to investigate the effect of flow intensity and exposure time on the breakage of precipitates during transport. Computational fluid dynamic (CFD) simulations were performed to evaluate the turbulent energy dissipation rate ( ɛ ) and associated exposure time along various flow geometries. A breakage model, incorporating the CFD output and experimentally determined parameter values, was found to provide a satisfactory capability for predicting the breakage of the protein precipitate particles. The breakage modelling approach was then applied to particles formed under different agitation intensities during the precipitation process. The formation history of the precipitates had a significant effect on their structure and strength and hence different breakage rates were observed. The precipitate dispersions were propelled through a number of different geometries such as bends, tees and elbows. The shape of the flow geometry was found to have an important effect on particle size reduction. This predictive particle breakage modelling approach was then applied to larger-scale flow geometries with cross-sectional area of 150 times greater than the experimental.

The breakage of liquid–liquid, solid–liquid and solid–gas dispersions occurs in many industrial processes during the transport of particulate materials. In this work, breakage of whey protein precipitates passing through a capillary pipe is examined and an experimentally derived breakage frequency is applied to construct a suitable population balance model to characterize the breakage process. It has been shown that the breakage frequency of precipitate particles is highly dependent on their shear history and on the turbulent energy dissipation rate in the pipe. The population balance equation (PBE) uses a volume density based discrete method which is adapted from mass density based discretization. In addition to comparing the model with experimental data, predicted results at different velocities are presented. It was found that the population balance breakage model provides satisfactory results in terms of predicting particle size distributions for such processes.

There is a global shift in education from solely content-driven teaching to teaching that takes learning outcomes into account. This movement underpins much of the educational reform in the area of engineering education. Programme learning outcomes for degrees in engineering education are more commonplace as more and more professional accrediting bodies require fulfillment or compliance with prescribed learning outcomes. However, the students may not be presented with these learning outcomes as they are often “hidden” in documentation submitted by institutions for accreditation purposes and hence may not be divulged to students. Undergraduate students (2006–2008) taking the BE degree programme in Process & Chemical Engineering at UCC were first surveyed to assess their level of knowledge of the learning outcomes concept and of the degree programme learning outcomes. The contents of two documents used in applications for accreditation by professional accreditation bodies as well as professional Institution guidelines were reviewed to formulate the degree programme learning outcomes which were presented to the students. These students were then surveyed after the presentation. The results of the questionnaire completed by students demonstrated a major improvement in their knowledge of both the concept of learning outcomes and also of the degree programme learning outcomes. It also showed that the students found the session to be of overall beneficial value.

The effect of orifice diameter and orifice length on the breakage of flowing protein precipitates was evaluated. These orifices were intended to mimic the flow intensity present in certain valves, pumps, flow meters and centrifuges that might be present in the transportation of precipitates. Different orifice contraction ratios (0.12–0.36), orifice lengths (0.3, 1.0 and 3.5 mm) and flow rates (6.0–9.0 g s −1 ) were studied. The extent, rate and mechanism of precipitate disruption were significantly affected by all these variables. The energy dissipation rate ( ɛ ) within each flow geometry was computed using CFD. A wide range of ɛ values (3.4 × 10 2 to 1.4 × 10 6 m 2 s −3 ) was generated and at least two different breakage mechanisms were observed. The first mechanism dominates at high ɛ and is characterized by significant production of submicron particles; the other one dominates at low ɛ with negligible production of fines. Both the breakage rate and mechanism were modelled as continuous functions of ɛ . The proposed breakage model predicts that significant precipitate disruption will occur according to the former breakage mechanism in certain post-formation processing equipment.