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Integrated Approach of Intelligent Asset Maintenance and Resource Conservation for Circular Economy
Chin, Hon Huin ; Ditl, Pavel (oponent) ; Hanika, Jiří (oponent) ; Kravanja, Zdravko (oponent) ; Klemeš, Jiří (vedoucí práce)
The rapid global industrialisation and urbanisation have placed heavy burdens on natural material resources consumption. For example, water scarcity and water pollution have been affecting human lives and economic developments for a long time, and resorting to clean fresh water has been becoming an important issue. The increasing irregular water supply and water pollution issues require more advanced water resources assessment methodologies to guide practical water use and management. Another well-known issue is the plastic waste accumulation in the option, which raises an alarming concern in achieving the optimal resources conservation network, striving towards the goal of Circular Economy. The Circular Economy concept not only focuses on resources conservation but also highlights the importance of maintaining and preserving the assets’ lifetime. This thesis is focused on developing advanced approaches for resources conservation and asset maintenance This thesis presents the extended analysis of Pinch-based methods in conserving the material resources for an industrial site. The major extensions involve the conceptual analysis on the resource conservation network that involves multiple qualities constraints, headers targeting and synthesis, and Total Site material conservation network synthesis. These methods serve as the graphical user interface for the users to select the preferable design options while ensuring the fresh resources consumptions are minimal. The study also extends the incorporation of different types of resources, such as heat and water, into the conservation network. The management issues such as resources management, subsidies and cost allocations are also studied for the eco-industrial site. Considering the asset’s lifetime prolongation, the long-term planning of a process or industrial site is incorporated in this study covering the assets’ age, depreciation and reliability. Process Integration tools are proposed to plan for the maintenance cost for a time period and workforce scheduling. The study is also extended to more analysis involving standby units and technologies investment for any process. Combining asset performance with resources conservation, the fault diagnosis and prognosis framework is applied to the Total Site/Eco-industrial park asset maintenance planning.
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Integrated Approach of Intelligent Asset Maintenance and Resource Conservation for Circular Economy
Chin, Hon Huin ; Ditl, Pavel (oponent) ; Hanika, Jiří (oponent) ; Kravanja, Zdravko (oponent) ; Klemeš, Jiří (vedoucí práce)
The rapid global industrialisation and urbanisation have placed heavy burdens on natural material resources consumption. For example, water scarcity and water pollution have been affecting human lives and economic developments for a long time, and resorting to clean fresh water has been becoming an important issue. The increasing irregular water supply and water pollution issues require more advanced water resources assessment methodologies to guide practical water use and management. Another well-known issue is the plastic waste accumulation in the option, which raises an alarming concern in achieving the optimal resources conservation network, striving towards the goal of Circular Economy. The Circular Economy concept not only focuses on resources conservation but also highlights the importance of maintaining and preserving the assets’ lifetime. This thesis is focused on developing advanced approaches for resources conservation and asset maintenance This thesis presents the extended analysis of Pinch-based methods in conserving the material resources for an industrial site. The major extensions involve the conceptual analysis on the resource conservation network that involves multiple qualities constraints, headers targeting and synthesis, and Total Site material conservation network synthesis. These methods serve as the graphical user interface for the users to select the preferable design options while ensuring the fresh resources consumptions are minimal. The study also extends the incorporation of different types of resources, such as heat and water, into the conservation network. The management issues such as resources management, subsidies and cost allocations are also studied for the eco-industrial site. Considering the asset’s lifetime prolongation, the long-term planning of a process or industrial site is incorporated in this study covering the assets’ age, depreciation and reliability. Process Integration tools are proposed to plan for the maintenance cost for a time period and workforce scheduling. The study is also extended to more analysis involving standby units and technologies investment for any process. Combining asset performance with resources conservation, the fault diagnosis and prognosis framework is applied to the Total Site/Eco-industrial park asset maintenance planning.
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Local velocity scaling in upward flow to tooth impeller in a fully turbulent region
Šulc, R. ; Ditl, P. ; Fořt, I. ; Jašíková, D. ; Kotek, M. ; Kopecký, V. ; Kysela, Bohuš
The hydrodynamics and flow field were measured in an agitated vessel using 2-D Time Resolved Particle Image Velocimetry (2-D TR PIV). The experiments were carried out in a fully baffled cylindrical flat bottom vessel 400 mm in inner diameter agitated by a tooth impeller 133 mm in diameter. Distilled water was used as the agitated liquid. The velocity fields were investigated in the upward flow to the impeller for three impeller rotation speeds – 300 rpm, 500 rpm and 700 rpm, corresponding to a Reynolds number in the range 94 000 < Re < 221 000. This means that fully-developed turbulent flow was reached. This Re range secures the fully-developed turbulent flow in an agitated liquid. In accordance with the theory of mixing, the dimensionless mean and fluctuation velocities in the measured directions were found to be constant and independent of the impeller Reynolds number. On the basis of the test results the spatial distributions of dimensionless velocities were calculated. The axial turbulence intensity was found to be in the majority in the range from 0.4 to 0.7, which corresponds to the middle level of turbulence intensity.
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In-situ measurement of particle size distribution in an agitated vessel
Kysela, Bohuš ; Konfršt, Jiří ; Chára, Zdeněk ; Šulc, R. ; Ditl, P.
Agitation of solid-liquid suspension or two immiscible liquids is a frequent operation in chemical and metallurgical industries (suspension/emulsion polymerization, catalytic chemical reaction, hydrometallurgical solvent extraction). The product quality, yield and economy of the processes are significantly affected by a mixing process. Prediction of mean particle/drop size and particle/drop size distribution (PSD) during the agitation is fundamental for emulsification, suspension polymerization, solid particle dispersion or crystallization. \nThe aim of this contribution is to propose a simple method of in-situ measurement of particle size distribution. The particle size measurement is based on an image analysis performed on raw image records. Evaluation method based on the best focused particles with sharp detected boundaries enhanced by the analysis of particle circularity was developed. Precise spherical mono-disperse steel and plastic particles were used to verify accuracy of evaluation method. The method has been proposed for the measurement of the time evolution of the drop size distribution in liquid-liquid dispersion in an agitated tank. The effect of droplet size distribution on the impeller speed in wateroil dispersion in agitated vessel was obtained.
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The minimum record time for PIV measurement in a vessel agitated by a Rushton turbine
Šulc, R. ; Ditl, P. ; Fořt, I. ; Jašíková, D. ; Kotek, M. ; Kopecký, V. ; Kysela, Bohuš
In PIV studies published in the literature focusing on the investigation of the flow field in an agitated vessel the record time is ranging from the tenths and the units of seconds. The aim of this work was to determine minimum record time for PIV measurement in a vessel agitated by a Rushton turbine that is necessary to obtain relevant results of velocity field. The velocity fields were measured in a fully baffled cylindrical flat bottom vessel 400 mm in inner diameter agitated by a Rushton turbine 133 mm in diameter using 2-D Time Resolved Particle Image Velocimetry in the impeller Reynolds number range from 50 000 to 189 000. This Re range secures the fully-developed turbulent flow of agitated liquid. Three liquids of different viscosities were used as the agitated liquid. On the basis of the analysis of the radial and axial components of the mean- and fluctuation velocities measured outside the impeller region it was found that dimensionless minimum record time is independent of impeller Reynolds number and is equalled N. t(Rmin) = 103 +/- 19.
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Local velocity scaling in T400 vessel agitated by Rushton turbine in a fully turbulent region
Šulc, R. ; Ditl, P. ; Fořt, I. ; Jašíková, D. ; Kotek, M. ; Kopecký, V. ; Kysela, Bohuš
The hydrodynamics and flow field were measured in an agitated vessel using 2-D Time Resolved Particle Image Velocimetry (2-D TR PIV). The experiments were carried out in a fully baffled cylindrical flat bottom vessel 400 mm in inner diameter agitated by a Rushton turbine 133 mm in diameter. The velocity fields were measured in the zone in upward flow to the impeller for impeller rotation speeds from 300 rpm to 850 rpm and three liquids of different viscosities (i.e. (i) distilled water, ii) a 28% vol. aqueous solution of glycol, and iii) a 43% vol. aqueous solution of glycol), corresponding to the impeller Reynolds number in the range 50 000 < Re < 189 000. This Re range secures the fully-developed turbulent flow of agitated liquid. In accordance with the theory of mixing, the dimensionless mean and fluctuation velocities in the measured directions were found to be constant and independent of the impeller Reynolds number. On the basis of the test results the spatial distributions of dimensionless velocities were calculated. The axial turbulence intensity was found to be in the majority in the range from 0.388 to 0.540, which corresponds to the high level of turbulence intensity.
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Distribution of the turbulent kinetic dissipation rate in an agitated vessel
Kysela, Bohuš ; Sulc, R. ; Konfršt, Jiří ; Chára, Zdeněk ; Fořt, I. ; Ditl, P.
The design of the agitated tanks depends on the proposed operating conditions and processes\nfor that they are used for. Namely dissipation rate of the turbulent kinetic energy is important\nparameter for the scale-up modelling. The dissipation rate is commonly determined as integral\nvalue based on power input of the impeller, but without information about distribution inside\nthe agitated volume. The cumulative distributions of the dissipation rate within an agitated\nvessel are estimated by evaluations of the CFD (Computational Fluid Dynamics) results,\nwhere the data was obtained from RANS (Reynolds Averaged Navier-Stokes equations) and\nLES (Large Eddy Simulations). The simulations were performed for an agitated vessel\nequipped with four baffles and stirred by a standard Rushton turbine (tank diameter 0.3 m,\nimpeller diameter 0.1 m, off-bottom clearance half of tank diameter, impeller speed 200 rpm).\nThe values of the dissipation rate from the LES calculations were approximated by computing\nthe SGS (Sub Grid Scale) dissipation rate.
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