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Abstract: The article presents an engineering approach to the development of an alternative production with the existing equipment. Zeolite production is becoming an alternative to the old »Bayer« process for aluminum hydrate production. By applying appropriate know-how old equipment was used for an economically as well as ecologically acceptable production. In this equipment adaptation among other production steps the multistage evaporation battery was the most critical part of the process. We applied semi empirical approach on the basis of Z. Rant ideas to find heat transfer coefficients and to determine which equipment elements are more relevant for efficient performance and need serious maintenance.
Keywords: chemical engineering, evaporation in silicate technology, bauxite alumina production, evaporators, process optimization, heat transfer, heat flow, empirical equations, heat transfer coefficients, zeolites
Published in DKUM: 24.08.2017; Views: 1618; Downloads: 112
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Abstract: Fatty ester synthesis with immobilized 1,3-specific lipase from Mucor Miehei is described. 1,2-Isopropylidene glycerol was peoduced by condensation of glycerol with acetone was esterified with oleic acid in the presence of a Mucor Miehei lipaze (Lipozyme TM) to obtain 1,2 isopropylidene- 3-oleoyl glycerol. The effects of various process parameters (temperature and pressure)and various ratios (enzyme/substrate) have been investigated to determine optimal conditions for the esterification process. The highest conversion of oleic acid (80% w/w) was obtained at 55 oC and 57.057 bar, while the optimal addition of lipase to substrate was determined to be 0,096 g per gram of reaction mixture. The esterification can be modelled successfully as a reverse second order reaction. Thermodynamic properties of the reaction system at 55 oC and 0.057 bar were also determined. Activation energy was 20.82 kJ/mole, entropy of activation -0,26 kJ/(Kmole) and free energy of activation was 103.32 kJ/mole.
Keywords: chemical engineering, biotechnology, esterification, syntheses, esters, enzymes, lipase, Mucor miehei, reaction kinetics, reaction thermodynamics, 1, 2-isopropylidene-3-oleoyl glycerol
Published in DKUM: 06.06.2012; Views: 2549; Downloads: 100
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Abstract: Nowadays, the principles of sustainable development are becoming increasingly important and universities are acting as agents in promoting these principles within society. In the future, universities will inevitably play crucial role in propagating these principles. This paper highlights important documents and discusses definitions of the term education for sustainable development. Elements, based on continuous feedback loop (Deming spiral) are discussed, in order to incorporate sustainability principles into university activities. The University of Maribor has been used as a case study to test the effectiveness of the proposed integration of sustainable development principles.
Keywords: chemical engineering, trajnostni razvoj, sustainable university, higher education, study programs, environmental engineering
Published in DKUM: 01.06.2012; Views: 24392; Downloads: 108
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Abstract: This paper introduces the electronic Portal, reports on the experiences of its use, shows how it motivates students towards more successful study, encourages lecturers to give better lectures, enhances learning, and so reduces workloads. A group of students from the Department of Chemistry and Chemical Engineering in Maribor have used this Portal in their Process Synthesis Course for the last four years. Their responses to e-learning and the Portal were collected by means of a questionnaire. The students thought that the Portal was an effective tool that helped them to improve the quality and efficiency of their studies. They thought a combination of lectures and elearning to be the most suitable solution for them because it gives a freedom of choice in methods and time devoted to studying. They suggest that this kind of arrangement would be beneficial for use in the future. These statements could motivate college students to choose studies at departments that use modern technologies within the educational process and thus increase the enrolment in those departments. The faculties' responses to using the Portal are also presented. The results of their questionnaires were not as encouraging as the students'. A few lecturers had already used certain functions of the Portal but, in general, they thought that the incorporation of e-learning into the educational process means a heavier workload and is time-consuming. Perhaps the experiences of the lecturer for the Process Synthesis Course, who has been using e-learning for several years, will demonstrate that the incorporation of e-learning into the educational process leads to a heavier workload at the start, but this reduces over time. Perhaps this experience will encourage the faculty to reconsider.
Keywords: ICT, electronic tool, e-learning, chemical engineering courses
Published in DKUM: 31.05.2012; Views: 2045; Downloads: 37
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Abstract: The opportunities for additional profit depend very much on the existing plant and energy system. Heat and power integration can reduce fuel usage in chemical processes. Nonlinear programming contains equations which enable structural and parametric optimization. The NLP model is formulated using an optimum energy target of process integration and electricity generation using a gas turbine with separator. The reactor acts as a combustion chamber of the gas turbine plant, producing a lot of energy. The simultaneous NLP approach can account for capital cost, integration of combined heat and power, process modification and additional production of trade-offs, and can thus yield a better solution. The combined production of electricity, heat and chemical products can lead to better process efficiency. The methanol plant was optimized using a mathematical nonlinear programming model by including an additional flowrate of hydrogen in crude methanol recycle and increasing the methanol production by 2,5%. The electricity can be generated in methanol recycle using a gas turbine. The total additional profit is 2,5 MEUR/a.
Keywords: chemical engineering, methanol production, simultaneous process optimization, nonlinear programming, cogeneration, product increase
Published in DKUM: 30.05.2012; Views: 2644; Downloads: 51
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