Experiences on dynamic simulation software in chemical engineering education

Commercial process simulators are increasing interest in the chemical engineer education. In this paper, the use of commercial dynamic simulation software, D-SPICE® and K-Spice®, for three different chemical engineering courses is described and discussed. The courses cover the following topics: basic chemical engineering, operability and safety analysis and process control. User experiences from both teachers and students are presented. The benefits of dynamic simulation as an additional teaching tool are discussed and summarized. The experiences confirm that commercial dynamic simulators provide realistic training and can be successfully integrated into undergraduate and graduate teaching, laboratory courses and research. © 2012 The Institution of Chemical Engineers.

Practice based learning for automotive engineering design students

The automotive industry combines a multitude of professionals to develop a modern car successfully. Within the design and development teams the collaboration and interface between Engineers and Designers is critical to ensure design intent is communicated and maintained throughout the development process. This study highlights recent industry practice with the emergence of Concept Engineers in design teams at Jaguar Land Rover Automotive group. The role of the Concept Engineer emphasises the importance of the Engineering and Design/Styling interface with the Concept engineer able to interact and understand the challenges and specific languages of each specialist area, hence improving efficiency and communication within the design team. Automotive education tends to approach design from two distinct directions, that of engineering design through BSc courses or a more styling design approach through BA and BDes routes. The educational challenge for both types of course is to develop engineers and stylist's who have greater understanding and experience of each other's specialist perspective of design and development. The study gives examples of two such courses in the UK who are developing programmes to help students widen their understanding of the engineering and design spectrum. Initial results suggest the practical approach has been well received by students and encouraged by industry as they seek graduates with specialist knowledge but also a wider appreciation of their role within the design process.

Engineering design of an integrated sustainable process system for cassava biobased materials

Cassava contributes significantly to biobased material development. Conventional approaches for its bio-derivative-production and application cause significant wastes, tailored material development challenges, with negative environmental impact and application limitations. Transforming cassava into sustainable value-added resources requires redesigning new approaches. Harnessing unexplored material source, and downstream process innovations can mitigate challenges. The ultimate goal proposed an integrated sustainable process system for cassava biomaterial development and potential application. An improved simultaneous release recovery cyanogenesis (SRRC) methodology, incorporating intact bitter cassava, was developed and standardized. Films were formulated, characterised, their mass transport behaviour, simulating real-distribution-chain conditions quantified, and optimised for desirable properties. Integrated process design system, for sustainable waste-elimination and biomaterial development, was developed. Films and bioderivatives for desired MAP, fast-delivery nutraceutical excipients and antifungal active coating applications were demonstrated. SRRC-processed intact bitter cassava produced significantly higher yield safe bio-derivatives than peeled, guaranteeing 16% waste-elimination. Process standardization transformed entire root into higher yield and clarified colour bio-derivatives and efficient material balance at optimal global desirability. Solvent mass through temperature-humidity-stressed films induced structural changes, and influenced water vapour and oxygen permeability. Sevenunit integrated-process design led to cost-effectiveness, energy-efficient and green cassava processing and biomaterials with zero-environment footprints. Desirable optimised bio-derivatives and films demonstrated application in desirable in-package O2/CO2, mouldgrowth inhibition, faster tablet excipient nutraceutical dissolutions and releases, and thymolencapsulated smooth antifungal coatings. Novel material resources, non-root peeling, zero-waste-elimination, and desirable standardised methodology present promising process integration tools for sustainable cassava biobased system development. Emerging design outcomes have potential applications to mitigate cyanide challenges and provide bio-derivative development pathways. Process system leads to zero-waste, with potential to reshape current style one-way processes into circular designs modelled on nature's effective approaches. Indigenous cassava components as natural material reinforcements, and SRRC processing approach has initiated a process with potential wider deployment in broad product research development. This research contributes to scientific knowledge in material science and engineering process design.

Reduction of functionalized graphite oxides by trioctylphosphine in non-polar organic solvents

Graphene, functionalized with oleylamine (OA) and soluble in non-polar organic solvents, was produced on a large scale with a high yield by combining the Hummers process for graphite oxidation, an amine-coupling process to make OA-functionalized graphite oxide (OA-GO), and a novel reduction process using trioctylphosphine (TOP). TOP acts as both a reducing agent and an aggregation-prevention surfactant in the reduction of OA-GO in 1,2-dichlorobenzene (DCB). The reduction of OA-GO is confirmed by X-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, and Raman spectroscopy. The exfoliation of GO, OA GO, and OA-functionalized graphene (OA-G) is verified by atomic force microscopy. The conductivity of TOP-reduced OA G, which is deduced from the current–voltage characteristics of a vacuum-filtered thin film, shows that the reduction of functionalized GO by TOP is as effective as the reduction of GO by hydrazine.

Mixing and drying mud and ash at Tully Mill

Disposal of mud and ash, particularly in wet weather conditions, is a significant expense for mills. This paper reports on part of a process to pelletise mud and ash, aimed at making mud and ash more attractive to growers across entire mill districts. The full process and the re-constituting and centrifuging rotary vacuum filter mud part of the process were described in two papers to the 2011 conference. The component described in this paper involves aspects of mixing mud and ash with subsequent drying using boiler exit gas. The mud material needs to mix easily with boiler ash and the mixture has to feed easily into and be pneumatically conveyed by a flue gas dryer. The performance of a pilot flue gas dryer for drying mud and ash was evaluated. The mud and ash mixture was found to dry much faster than final bagasse, provided the mud and ash material was broken up into individual particles. A previously developed computer model of bagasse drying was updated to take into account the smaller particle size of the mud and ash mixture. This upgraded model predicted the performance of the pilot flue gas dryer well.

CSG A Greener Tomorrow : Comprehensive Organizational and Socialistic Report

Humans have altered environments and enhanced their wellbeing unlike any other creature on the planet (Hielman & Donda, 2007); this is no different whether the environment is ecological, social or organizational. In recent times, the debate regarding greenhouse effects on the global weather patterns and the sustainment of the earth’s temperature necessary for life support has become quite infamously problematic as society pushes to find new sources of energy both renewable and environmentally sustainable. The feedback received on CSG from both government and companies alike is that the opportunities this industry creates has a lasting range of social and economic benefits worth over fifty (50) billion dollars in projects (Queensland Government, 2013). This however, has been overshadowed by social activist and lobbyist groups as ‘Lock the Gate Alliance’ saying, as one part of their report noted from the National Water Commission, “coal seam gas development could cause significant social impacts by disrupting current land-use practices and the local environment through infrastructure construction and access” (Lock the Gate Alliance, n.d.), and “In recent years both a NSW and Federal Senate inquiry into coal seam gas production were deliberately mislead by an organization that claims to work on behalf of the farming community, This is the battle for the end of the fossil fuel industry. This is the end game..." (Ward, 2013).

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.

Graphene-based supercapacitor with carbon nanotube film as highly efficient current collector

Flexible graphene-based thin film supercapacitors were made using carbon nanotube (CNT) films as current collectors and graphene films as electrodes. The graphene sheets were produced by simple electrochemical exfoliation, while the graphene films with controlled thickness were prepared by vacuum filtration. The solid-state supercapacitor was made by using two graphene/CNT films on plastic substrates to sandwich a thin layer of gelled electrolyte. We found that the thin graphene film with thickness <1 μm can greatly increase the capacitance. Using only CNT films as electrodes, the device exhibited a capacitance as low as ~0.4 mF cm−2, whereas by adding a 360 nm thick graphene film to the CNT electrodes led to a ~4.3 mF cm−2 capacitance. We experimentally demonstrated that the conductive CNT film is equivalent to gold as a current collector while it provides a stronger binding force to the graphene film. Combining the high capacitance of the thin graphene film and the high conductivity of the CNT film, our devices exhibited high energy density (8–14 Wh kg−1) and power density (250–450 kW kg−1).

Evaluation of mud filtrate clarification to improve factory performance

Clarification performance and flocculant dosage is strongly linked to the mud solids loading in the feed entering the clarifier. The recycle of filtrate can represent an extra ~10-15% mud solids loading on the clarifier, thereby reducing its effective capacity. Filtrate recycling may cause significant increase in turbidity, complexed calcium ion formation, phosphate, proteins and polysaccharides in mixed juice that impact on evaporator scale formation and molasses exhaustion. The paper details the results obtained from laboratory, pilot scale and factory trials of filtrate clarification using both sedimentation and flotation methods. Clarified filtrate could be produced of similar quality to ESJ. Filtrate clarification was able to significantly remove insoluble solids, turbidity, phosphate, and polysaccharides content with slight reductions in minerals content of the filtrate. On the basis of improved filtrate quality, the clarified filtrate could be directed to ESJ, instead of the normal practice of directing the mud filtrate to mixed juice. The potential impacts of implementing filtrate clarification are discussed in respect to improved performance and throughput of the clarification station.

Modular continuous crystallizer: operation, experimental arrangement and identification of process parameters

Crystallization is employed in different industrial processes. The method and operation can differ depending on the nature of the substances involved. The aim of this study is to examine the effect of various operating conditions on the crystal properties in a chemical engineering design window with a focus on ultrasound assisted cooling crystallization. Batch to batch variations, minimal manufacturing steps and faster production times are factors which continuous crystallization seeks to resolve. Continuous processes scale-up is considered straightforward compared to batch processes owing to increase of processing time in the specific reactor. In cooling crystallization process, ultrasound can be used to control the crystal properties. Different model compounds were used to define the suitable process parameters for the modular crystallizer using equal operating conditions in each module. A final temperature of 20oC was employed in all experiments while the operating conditions differed. The studied process parameters and configuration of the crystallizer were manipulated to achieve a continuous operation without crystal clogging along the crystallization path. The results from the continuous experiment were compared with the batch crystallization results and analysed using the Malvern Morphologi G3 instrument to determine the crystal morphology and CSD. The modular crystallizer was operated successfully with three different residence times. At optimal process conditions, a longer residence time gives smaller crystals and narrower CSD. Based on the findings, at a constant initial solution concentration, the residence time had clear influence on crystal properties. The equal supersaturation criterion in each module offered better results compared to other cooling profiles. The combination of continuous crystallization and ultrasound has large potential to overcome clogging, obtain reproducible and narrow CSD, specific crystal morphologies and uniform particle sizes, and exclusion of milling stages in comparison to batch processes.

Optimal design of multiproduct batch chemical plant using NSGA-II

The optimal design of a multiproduct batch chemical plant is formulated as a multiobjective optimization problem, and the resulting constrained mixed-integer nonlinear program (MINLP) is solved by the nondominated sorting genetic algorithm approach (NSGA-II). By putting bounds on the objective function values, the constrained MINLP problem can be solved efficiently by NSGA-II to generate a set of feasible nondominated solutions in the range desired by the decision-maker in a single run of the algorithm. The evolution of the entire set of nondominated solutions helps the decision-maker to make a better choice of the appropriate design from among several alternatives. The large set of solutions also provides a rich source of excellent initial guesses for solution of the same problem by alternative approaches to achieve any specific target for the objective functions