The Experts below are selected from a list of 150 Experts worldwide ranked by ideXlab platform
Hermann Nirschl - One of the best experts on this subject based on the ideXlab platform.
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Filter Cake Washing of Mesoporous Particles
Chemical Engineering & Technology, 2012Co-Authors: S. Noerpel, V. Siauw, Hermann NirschlAbstract:Particle synthesis in liquid phase usually requires a subsequent Washing step in order to remove undesirable impurities such as unreacted educts, byproducts, solvents and salts. In particular, the Washing of mesoporous particles is a challenging task due to large specific surface areas and void volumes. The filter Cake Washing of mesoporous SiO2 particles contaminated either with an adsorbing fluorescent dye or sodium sulfate is presented. The effects of wash liquid mass flow rate, mean particle size, and mean pore size on the wash efficiency were investigated. Especially the interaction between impurities and the solid surface, and thereby the initial impurity distribution within the filter Cake, led to distinctive Washing behaviors.
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Adaptation of Optimum Washing Strategies to Product and Process Parameters in Centrifugal Processes
Chemical Engineering & Technology, 2010Co-Authors: Franky Ruslim, Ates Erk, Thomas Danner, Valentin Wenzel, Hermann NirschlAbstract:Filter Cake Washing is a purification process during solid/liquid separation which is applied to various particulate products with different product properties. A generalization of the Washing strategy is in most cases not possible nor is it reasonable due to product diversity. This paper presents an overview of the adaptation of the optimum Washing strategies in centrifuges to different process parameters and product properties, such as Cake structure and permeability.
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the influence of temporal Cake moisture content on a discontinuous Washing process in the centrifugal field
Aiche Journal, 2009Co-Authors: Franky Ruslim, Hermann Nirschl, W Stahl, Philippe CarvinAbstract:In solid/liquid separation processes, filter Cake Washing is an essential step in improving the quality of particulate products by elimination of impurities. During Cake Washing and dewatering, the Cake saturation changes depending on the flow conditions and it cannot always be measured and controlled accurately. This article deals with investigations on the influence of the initial and temporal Cake saturation on Washing PVC and silica sand particles in the centrifugal field. It was found, that high initial saturation levels and high maximum saturations during the Washing process had a positive impact in inducing a high hydrostatic pressure for advective flow and enabling a homogeneous distribution of the wash water inside the Cake. This was achieved by increasing the wash water flux and/or decreasing the g-factor. A good method to obtain low final impurity quantity is the combination of Washing at a low g-factor and dewatering at a high one. © 2009 American Institute of Chemical Engineers AIChE J, 2009
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Evaluation of pathways for Washing soluble solids
Chemical Engineering Research and Design, 2009Co-Authors: Franky Ruslim, Hermann Nirschl, Bernhard Hoffner, Werner StahlAbstract:Abstract Filter Cake Washing is a purification method for particulate products in liquids. This process is mostly one step of a sequence in a solid–liquid separation process. For soluble products not only the mechanical transport mechanisms in Washing but also the dissolution process of the product must be considered in order to describe the Washing process appropriately. An unconsidered dissolution may cause problems and often severe product loss depending on the material properties. This paper presents several methods of soluble solids Washing including filter Cake Washing by pressure and centrifugal forces as well as moving bed Washing. The advantages and drawbacks of each method are discussed to evaluate the suitability of its technical application.
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calcium ion removal from peat by a mechanical filter Cake Washing process
Chemical Engineering & Technology, 2007Co-Authors: Franky Ruslim, Hermann Nirschl, Antonina Mezhibor, Leonid RikhvanovAbstract:This contribution aims to bridge two different fields of science, viz., geoecology and mechanical process engineering. The study reports on the application of mechanical Washing processes especially filter Cake Washing, on calcium-ion removal from peat, which is a natural material that is used in different fields of application such as agriculture, medicine, cosmetics, etc. The interesting properties of peat such as its porous structure and the sorption behavior influence the distribution of liquid inside the bulk and the liquid flow behavior through the porous structure. Experimental results are obtained from filtration tests using differential gas pressure in a filter nutsche. The Washing efficiency is determined for different pressures and specific amounts of applied wash liquor. It is found that the water repellent phenomena that occurs when peat has been dried, affects the Washing efficiency in a very negative way. The results obtained are compared to the conventional filter Cake Washing process.
Franky Ruslim - One of the best experts on this subject based on the ideXlab platform.
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Adaptation of Optimum Washing Strategies to Product and Process Parameters in Centrifugal Processes
Chemical Engineering & Technology, 2010Co-Authors: Franky Ruslim, Ates Erk, Thomas Danner, Valentin Wenzel, Hermann NirschlAbstract:Filter Cake Washing is a purification process during solid/liquid separation which is applied to various particulate products with different product properties. A generalization of the Washing strategy is in most cases not possible nor is it reasonable due to product diversity. This paper presents an overview of the adaptation of the optimum Washing strategies in centrifuges to different process parameters and product properties, such as Cake structure and permeability.
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the influence of temporal Cake moisture content on a discontinuous Washing process in the centrifugal field
Aiche Journal, 2009Co-Authors: Franky Ruslim, Hermann Nirschl, W Stahl, Philippe CarvinAbstract:In solid/liquid separation processes, filter Cake Washing is an essential step in improving the quality of particulate products by elimination of impurities. During Cake Washing and dewatering, the Cake saturation changes depending on the flow conditions and it cannot always be measured and controlled accurately. This article deals with investigations on the influence of the initial and temporal Cake saturation on Washing PVC and silica sand particles in the centrifugal field. It was found, that high initial saturation levels and high maximum saturations during the Washing process had a positive impact in inducing a high hydrostatic pressure for advective flow and enabling a homogeneous distribution of the wash water inside the Cake. This was achieved by increasing the wash water flux and/or decreasing the g-factor. A good method to obtain low final impurity quantity is the combination of Washing at a low g-factor and dewatering at a high one. © 2009 American Institute of Chemical Engineers AIChE J, 2009
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Evaluation of pathways for Washing soluble solids
Chemical Engineering Research and Design, 2009Co-Authors: Franky Ruslim, Hermann Nirschl, Bernhard Hoffner, Werner StahlAbstract:Abstract Filter Cake Washing is a purification method for particulate products in liquids. This process is mostly one step of a sequence in a solid–liquid separation process. For soluble products not only the mechanical transport mechanisms in Washing but also the dissolution process of the product must be considered in order to describe the Washing process appropriately. An unconsidered dissolution may cause problems and often severe product loss depending on the material properties. This paper presents several methods of soluble solids Washing including filter Cake Washing by pressure and centrifugal forces as well as moving bed Washing. The advantages and drawbacks of each method are discussed to evaluate the suitability of its technical application.
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calcium ion removal from peat by a mechanical filter Cake Washing process
Chemical Engineering & Technology, 2007Co-Authors: Franky Ruslim, Hermann Nirschl, Antonina Mezhibor, Leonid RikhvanovAbstract:This contribution aims to bridge two different fields of science, viz., geoecology and mechanical process engineering. The study reports on the application of mechanical Washing processes especially filter Cake Washing, on calcium-ion removal from peat, which is a natural material that is used in different fields of application such as agriculture, medicine, cosmetics, etc. The interesting properties of peat such as its porous structure and the sorption behavior influence the distribution of liquid inside the bulk and the liquid flow behavior through the porous structure. Experimental results are obtained from filtration tests using differential gas pressure in a filter nutsche. The Washing efficiency is determined for different pressures and specific amounts of applied wash liquor. It is found that the water repellent phenomena that occurs when peat has been dried, affects the Washing efficiency in a very negative way. The results obtained are compared to the conventional filter Cake Washing process.
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Optimization of the wash liquor flow rate to improve Washing of pre-deliquored filter Cakes
Chemical Engineering Science, 2007Co-Authors: Franky Ruslim, Hermann Nirschl, Werner Stahl, Philippe CarvinAbstract:Abstract Filter Cake Washing is a common way of improving the quality in purity of particulate products in solid–liquid separation processes. In industrial applications, this process step is usually treated as a black box where optimization is performed through trial and error. Decisive progress has been made in academia by the development of physical models to describe the Washing phenomena inside a porous structure such as filter Cakes. Although some models have led to a better understanding of the process, experimental efforts are still inevitable for determining optimization strategies. This contribution is an empirical approach to investigate the influence of important process parameters of Washing pre-deliquored Cakes with the focus on the wash liquor and filtrate flow rate. In Washing a pre-deliquored Cake, low moisture content at the time of wash liquor addition can be very disadvantageous for the wash efficiency due to inhomogeneous flow. This can be the result of a poor re-wetting process while Washing at low wash liquor flow rates. An increase of the flow rate was observed to be very advantageous to set higher moisture content of the filter Cake and therefore enforce a homogeneous distribution of the wash liquor. A homogeneous distribution of the wash liquor inside the Cake is generally required for good Washing.
Philippe Carvin - One of the best experts on this subject based on the ideXlab platform.
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the influence of temporal Cake moisture content on a discontinuous Washing process in the centrifugal field
Aiche Journal, 2009Co-Authors: Franky Ruslim, Hermann Nirschl, W Stahl, Philippe CarvinAbstract:In solid/liquid separation processes, filter Cake Washing is an essential step in improving the quality of particulate products by elimination of impurities. During Cake Washing and dewatering, the Cake saturation changes depending on the flow conditions and it cannot always be measured and controlled accurately. This article deals with investigations on the influence of the initial and temporal Cake saturation on Washing PVC and silica sand particles in the centrifugal field. It was found, that high initial saturation levels and high maximum saturations during the Washing process had a positive impact in inducing a high hydrostatic pressure for advective flow and enabling a homogeneous distribution of the wash water inside the Cake. This was achieved by increasing the wash water flux and/or decreasing the g-factor. A good method to obtain low final impurity quantity is the combination of Washing at a low g-factor and dewatering at a high one. © 2009 American Institute of Chemical Engineers AIChE J, 2009
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Optimization of the wash liquor flow rate to improve Washing of pre-deliquored filter Cakes
Chemical Engineering Science, 2007Co-Authors: Franky Ruslim, Hermann Nirschl, Werner Stahl, Philippe CarvinAbstract:Abstract Filter Cake Washing is a common way of improving the quality in purity of particulate products in solid–liquid separation processes. In industrial applications, this process step is usually treated as a black box where optimization is performed through trial and error. Decisive progress has been made in academia by the development of physical models to describe the Washing phenomena inside a porous structure such as filter Cakes. Although some models have led to a better understanding of the process, experimental efforts are still inevitable for determining optimization strategies. This contribution is an empirical approach to investigate the influence of important process parameters of Washing pre-deliquored Cakes with the focus on the wash liquor and filtrate flow rate. In Washing a pre-deliquored Cake, low moisture content at the time of wash liquor addition can be very disadvantageous for the wash efficiency due to inhomogeneous flow. This can be the result of a poor re-wetting process while Washing at low wash liquor flow rates. An increase of the flow rate was observed to be very advantageous to set higher moisture content of the filter Cake and therefore enforce a homogeneous distribution of the wash liquor. A homogeneous distribution of the wash liquor inside the Cake is generally required for good Washing.
Ross E. Swaney - One of the best experts on this subject based on the ideXlab platform.
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flowsheet synthesis of fractional crystallization processes with Cake Washing
Computers & Chemical Engineering, 2004Co-Authors: Luis A. Cisternas, Jessica Y. Cueto, Ross E. SwaneyAbstract:Abstract A flowsheet synthesis methodology is presented for the design of fractional crystallization processes. The methodology is based on four interconnected/nested networks. The first network is derived by identifying a set of thermodynamic states providing a basis for feasible separation alternatives. In this network, the nodes correspond to multiple saturation points, solute intermediates, and process feeds and end products. The second network type represents the variety of tasks that can be performed at each multiple saturation point. These tasks include cooling crystallization, evaporative crystallization, reactive crystallization, dissolution, and leaching. Heat integration is incorporated using the transshipment formulation to represent the heat exchanger network. The fourth network represents the filtration and Cake Washing alternatives. The Cake wash and task networks are modeled using disjunctive programming and then converted into a mixed-integer program. The method is applied to the design of three salt separation example problems. The optimal design costs are seen to depend on design parameters such as product impurity level and liquid retention in the Cake. The advantage of an integrated synthesis approach is demonstrated.
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Complete separation system synthesis of fractional crystallization processes
Computer Aided Chemical Engineering, 2003Co-Authors: Luis A. Cisternas, Jessica Y. Cueto, Ross E. SwaneyAbstract:Abstract A methodology is presented for the synthesis of fractional crystallization processes. The methodology is based on the construction of four networks. The first network is based on the identification of feasible thermodynamic states. In this network the nodes correspond to multiple saturation points, solute intermediate, process feeds and end products. The second network is used to represent the variety of tasks that can be performed at each multiple saturation point. These tasks include cooling crystallization, evaporative crystallization, reactive crystallization, dissolution, and leaching. Heat integration is included using a heat exchanger network which can be regarded as a transhipment problem. The last network is used to represent filtration and Cake Washing alternatives. The Cake wash and task networks are modelled using disjunctive programming and then converted into a mixed integer program. The method is illustrated through the design of a salt separation example.
Nina Salmela - One of the best experts on this subject based on the ideXlab platform.
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filter Cake Washing partial dissolution of organic particles and real time monitoring based on raman spectroscopy
Separation and Purification Technology, 2008Co-Authors: Marjatta Louhikultanen, Nina Salmela, Juha Kallas, Lars NystromAbstract:The partial dissolution of crystalline material during filter Cake Washing can affect greatly on the Cake permeability in separation and purification processes. Besides decreasing the Cake thickness, the dissolving may cause changes in the Cake structure as it may alter the particle size distribution based on the fact that different sized particles have different dissolution rates. This is especially the case if the Cake consists of particles having a wide particle size distribution. The present work introduces a model based on mass transfer to predict the dissolution rates of crystalline material having different solubility in various Washing liquors. The filtration system studied experimentally was ground sucrose filtered from ethanol solution. In addition, inline monitoring of the filtration and Cake Washing with a Raman spectrometer immersion probe was carried out. The studied impurity was cyclohexane. The measuring method allowed measuring of the ternary compound system: the impurity, the concentrations of the mother liquor and the solid in the filter Cake.
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monitoring and modelling of starch Cake Washing
International Journal of Food Science and Technology, 2006Co-Authors: Nina Salmela, Marja OjaAbstract:Summary This study describes the Washing of starch filter Cakes in a filter press, and shows an easy, simple and reliable method for the prediction of starch Cake Washing. The specific properties of starch particles that affect the filtration behaviour are introduced, as well as the starch pressure filtration process cycle, the monitoring of the Cake Washing process in a filter press, the sampling of the filter Cake, and the modelling of the Washing process. The monitoring of the Washing process for industrial-scale Cake Washing operations is quite difficult, and a prediction of the result is needed. The use of the simple model in predicting the Washing process is for the purpose of making the Washing process easier. The results obtained show that the starch Cake Washing can be effectively carried out in a filter press and the behaviour of the starch Cake during Washing can be interpreted with the Washing models if the filtration properties of that starch are known.
