ソーシャルインクルージョンの醸成を目的とした障害に対する理解を深めるワークショップのあり方に関する研究 - チュニジアでの視覚障害を事例として

博士（芸術工学）神戸芸術工科大学201

Experimental and Theoretical Thermodynamic Study of Distillable Ionic Liquid 1,5-Diazabicyclo[4.3.0]non-5-enium Acetate

© 2016 American Chemical Society.A thermochemical study of the protic ionic liquid 1,5-diazabicyclo[4.3.0]non-5-enium acetate ([DBNH][OAc]), a prospective cellulose solvent considered for the Ioncell-F process, was carried out. The heat capacities of 1,5-diazabicyclo[4.3.0]non-5-ene (DBN) and [DBNH][OAc] were measured by differential scanning calorimetry (DSC) at 223-323 and 273-373 K temperature ranges, respectively. The enthalpies of fusion and synthesis reaction of [DBNH][OAc] were measured by DSC and reaction calorimetry, respectively. The gas-, liquid-, and solid-phase enthalpies of formation of [DBNH][OAc] and DBN were determined using calorimetric and computational methods. The enthalpy of vaporization of [DBNH][OAc] was estimated from the formation enthalpies. The activity coefficients at infinite dilution of 17 and the enthalpies of solution at infinite dilution of 25 organic solutes in [DBNH][OAc] were measured by gas chromatography and solution calorimetry methods, respectively. The obtained data will be used in the design and optimization of the Ioncell-F process

Solution of bivariate population balance equations with high-order moment-conserving method of classes

In this work the high-order moment-conserving method of classes (HMMC) (Alopaeus et al., 2006) is extended to solve the bivariate Population Balance Equation (PBE). The method is capable of guaranteeing the internal consistency of the discretized equations for a generic moment set, including mixed-order moments of the distribution. The construction of the product tables in the case of aggregation, breakage and convection in internal coordinate space are discussed. Eventually, several test cases are considered to assess the accuracy of the method. The application to a realistic mass transfer problems in a liquid-liquid system is preliminarily discussed. The comparison with analytical solutions of pure aggregation problems shows that the proposed method is accurate with only a limited number of categories

Improving Group Contribution Methods by Distance Weighting

A novel approach for improving estimations of existing group contribution methods is developed. Instead of fixed contributions, weighted contributions are optimized for each property estimation using a database. These weighting factors are calculated based on similarities between the compound whose properties are estimated and the other compounds in the database. By this approach, those components which are chemically more similar to the estimated one can systematically be given more weight in the estimation process, while sustaining the general nature of the group contribution methods. The new approach was applied to the Joback and Reid (1987), and the Marrero and Gani (2001) group contribution methods. The performances were demonstrated on Normal Boiling Point (NBP) predictions. The absolute average error of NBP estimations was reduced by 6.3 K for the Joback and Reid method and by 4 K for the Marrero and Gani method. Other physical properties such as critical pressure, volume, formation energies, melting temperature and fusion enthalpy were estimated by applying the new technique to Joback and Reid method

A novel simplified multivariate PBE solution method for mass transfer problems

Interphase mass transfer estimation may require not only the accurate knowledge of the interfacial area, which depends on the information about the size of each dispersed element, but also on the driving force, that can be different if the elements of the disperse phase have different chemical composition. To take into account such polydispersity, bivariate (or multivariate) population balance model (PBM) are formulated according to physical phenomena occurring in the investigated mass transfer problem. This often includes aggregation, breakage, advection, mass transfer of the chemical species and chemical reactions of the transferring components. In this work we propose a novel and simplified method to solve the bivariate/multivariate population balance equation for a mass transfer problem, based on the high-order moment-conserving method of classes (HMMC) (Alopaeus et al., 2006). The proposed method is based on the idea of deriving additional material balance equations for the concentration of droplets belonging to each size class, reducing significantly the total number of unknown variables with respect to true bivariate/multivariate method of classes. This modeling approach is compared with two other possible solution methods for a test case in which mass transfer and chemical reactions occur in a system with two immiscible liquid phases. In the first the traditional approach is used, where a single material balance is formulated for the disperse phase along with PBM, while in the second a true bivariate/multivariate solution method is used. The results of this comparison show that the proposed method is robust and accurate, capable of properly describing the multidimensional droplet size-composition distribution needed to evaluate the mass transfer rates, in a fraction of computational time compared with more accurate methods

Experimental determination of size distributions

The measurement of various particle size distributions is a crucial aspect for many applications in the process industry. Size distribution is often related to the final product quality, as in crystallization or polymerization. In other cases it is related to the correct evaluation of heat and mass transfer, as well as reaction rates, depending on the interfacial area between the different phases or to the assessment of yield stresses of polycrystalline metals/alloys samples. The experimental determination of such distributions often involves laborious sampling procedures and the statistical significance of the outcome is rarely investigated. In this work, we propose a novel rigorous tool, based on inferential statistics, to determine the number of samples needed to obtain reliable measurements of size distribution, according to specific requirements defined a priori. Such methodology can be adopted regardless of the measurement technique used.Peer reviewe

Liquid-liquid extraction in a rotating disc column: Solution of 2D population balance with HMMC

In this work mass transfer in liquid-liquid extraction is investigated with the two-dimensional high-order moment-conserving method of classes (2D-HMMC) (Buffo and Alopaeus, 2016). The solution of a realistic liquid-liquid test case, a counter-current rotating disc column (RDC) composed of three stages where the droplets exchange mass with the continuous phase, is studied. This detailed modelling approach is compared with two other possible approximated models. In the first all the droplets are assumed to have the same size and concentration, and in the second all the droplets are assumed to have the same concentration but different sizes. The results of this comparison show that the information regarding the two-dimensional droplet size-concentration distribution may be needed to properly evaluate the mass transfer rates and therefore the behaviour of the system for all the operating conditions investigated

Modeling of gas-liquid packed-bed reactors with momentum equations and local interaction closures

An algebraic model for the estimation of gas−liquid packed-bed hydrodynamic parameters is developed, based on one-dimensional material and momentum balances for gas and liquid phases. Underlying momentum exchange closures are critically analyzed, which leads to discarding some interaction models between the phases and development of new models based on local hydrodynamics. The present approach is based on more-relevant assumptions for the particle scale geometry than the slit models presented in the literature. The resulting model requires a one-parameter iterative solution, from which both pressure drop and liquid holdup are obtained. The model can be used without any extra complication in situations where the boundary conditions are specified either at the inlet or at the outlet of the reactor. It is suitable for modeling both low- and high-pressure operations, trickling as well as pulsing flow, upflow and downflow arrangements, and processes with Newtonian as well as non-Newtonian liquids. Finally, the present model is compared to its differential counterpart, and to available experimental data from open literature. Reasonably good agreement was observed for both pressure drop and liquid holdup data from a wide range of operating conditions, using only a single set of Ergun parameters