Thesis (Ph. D.)--Oregon State University, 2004. / Printout. Includes bibliographical references. Also available on the World Wide Web.

This thesis presents procedures to properly simulate naturally fractured reservoirs using dual-porosity models. The main objectives of this work are to: (1) determine if the spontaneous imbibition can be simulated using a two phase CMG simulator and validate it with laboratory experiments in the literature; (2) study the effect of countercurrent imbibition in field scale applications; and (3) develop procedures for using the dual-porosity to simulate fluid displacement in a naturally fractured reservoir. Reservoir simulation techniques, analytical solutions and numerical simulation for a two phase single and dual-porosity are used to achieve our objectives. Analysis of a single matrix block with an injector and a producer well connected by a single fracture is analyzed and compared with both two phase single and dual-porosity models. Procedures for obtaining reliable results when modeling a naturally fractured reservoir with a two phase dual-porosity model are presented and analyzed.

Thesis (MEng) -- Stellenbosch University, 2014. / ENGLISH ABSTRACT: Supercritical fluids are enjoying ever increasing popularity as a solvent medium for extraction, stripping and absorption processes. Being readily tuneable and able to achieve sharp, highly efficient separations, supercritical fluids present an attractive alternative to traditional solvents, while using less intrinsically harmful compounds. Although the potential of supercritical fluids as solvents have been known for more than a century, there are still several areas of uncertainty, one being the hydrodynamics of extraction columns operating under supercritical conditions. This shortcoming can be attributed to the satisfactory performance of modified standard hydrodynamics to approximate column design, along with a predominant culture of overdesign in process engineering. Even though modified subcritical hydrodynamic models provide a good approximation they do not successfully predict the effect of changes in density, viscosity and surface tension of a supercritical fluid, leading to inaccuracies in column design. This study investigates the state of hydrodynamics under supercritical conditions in counter current packed columns discussed in literature, identifies shortcomings in existing literature and devises a way of addressing the said shortcomings. The primary objective of this study is to establish a multipurpose supercritical pilot plant capable of measuring hydrodynamics under supercritical conditions, followed by the secondary objective of measuring preliminary hydrodynamic data to prove the plant can deliver on its design requirements in measuring reliable hydrodynamic data. During a survey of available literature it was found that very little experimental work has been performed on hydrodynamics under supercritical conditions and especially on random packings. Further it is found that the systems investigated in literature were conducted under conditions of significant mass transfer. As mass transfer directly affects flow rates and fluid properties of the fluids in the column, it is vital to use systems with very little to no mass transfer. This ensures the most accurate approach possible when investigating fundamental hydrodynamic behaviour. Finally it was found that there are no well-defined correlations available for a wide range of packings, fluid properties and hydrodynamic phenomena for columns under supercritical conditions. To remedy the shortcomings in hydrodynamic data it was decided that more pilot plant work is required. It was found that no pilot plants available can measure hydrodynamic data. An investigation was performed into retrofitting available pilot plants, plants used by other research groups and commercially available plants. It was concluded that the best option was to salvage the major parts of an existing old pilot plant and use them to construct a new, customized pilot plant. This provides the opportunity of constructing a custom, multipurpose pilot plant capable of use in future research. After an initial concept design a full design of the new pilot plant was performed. The plant consists of two columns of 17 mm and 38 mm inside diameter and 3.5 m and 1.5 m packed height, respectively, and is capable of pressures and temperatures of up to 300 bar and 200°C. Furthermore the pilot plant can measure liquid hold-up, pressure drop, flooding and entrainment in accordance with the objective of measuring supercritical hydrodynamic data. Liquid hold-up was determined by stopping the process and allowing the column to drain, after which the volume drained was measured. To measure the pressure drop an Endress+Hauser Deltabar S PMD75 DP cell was used. Flooding was determined using the measured pressure drop and volumetric rate of column overheads, from where a hydrodynamically inoperable state is defined. Overall entrainment, although unlikely due to the presence of a demister in the column, was investigated by comparing the column overheads to literature phase equilibria. Preliminary hydrodynamic testing was performed using the 38mm diameter column packed with 1/4” Dixon rings. Testing is performed with at 120 bar and 40°C with a CO2 supercritical phase and polyethylene glycol liquid phase with an average molar mass of 400 (PEG 400). The hydrodynamic data gathered showed expected trends, but showed discrepancy with literature due to differences in liquids used, column packing and experimental system between the respective studies. / AFRIKAANSE OPSOMMING: Superkritiese vloeistowwe is besig om toenemende gewildheid as 'n oplosmiddel vir ekstraksie, stroping en absorpsie prosesse te geniet. Hierdie gewildheid is as gevolg van ʼn vermoë om skerp, hoogs effektiewe skeidings te bewerkstellig deur gebruik te maak van ʼn maklik aanpasbare oplosmiddel wat minder intrinsiek skadelik is as tradisionele oplosmiddels. Hierdie voordele lei daartoe dat superkritiese vloeiers as ʼn aantreklike alternatief tot tradisionele oplosmiddels gesien kan word. Alhoewel die potensiaal van superkritiese vloeistowwe as oplosmiddels al vir meer as ʼn eeu bekend is, is nog weinig eksperimentele werk al gedoen oor die hidrodinamiese gedrag van superkritiese gepakte kolomme. Hierdie tekortkoming kan toegeskryf word tot die bevredigende prestasie van aangepaste standaard hidrodinamiese korrelasies gedurende superkritiese kolomontwerp en ʼn oorheersende kultuur van oorontwerp in proses-ingenieurswese. Alhoewel aangepaste standaard hidrodinamiese korrelasies ʼn aanvaarbare benadering bied, beeld dit nie die effek van die veranderde digtheid, viskositeit en oppervlakspanning van ʼn superkritiese vloeistof uit nie, wat lei tot foute in kolomontwerp. Hierdie studie ondersoek die stand van superkritiese hidrodinamika in literatuur, spesifiek in teenstroom gepakte kolomme. Tekortkominge in die bestaande literatuur is geïdentifiseer en 'n metode om die genoemde tekortkominge reg te stel is bedink. Die primêre doel van hierdie studie is om 'n veeldoelige superkritiese loodsaanleg te bou wat tot staat is om superkritiese hidrodinamika te meet, gevolg deur die sekondêre doelwit wat die meet van voorlopige hidrodinamiese data behels, wat sal bewys dat die loodsaanleg voldoen aan ontwerpsvereistes. Tydens 'n opname van beskikbare literatuur was daar gevind dat weinig eksperimentele werk al gedoen is in die veld van superkritiese hidrodinamika, en nog minder oor sogenoemde ongeordende of ‘random’ kolompakkings. Verder is daar gevind dat eksperimente uitgevoer in literatuur slegs bestaan uit stelsels waar beduidende massa-oordrag plaasvind. Aangesien massa-oordrag die vloeitempo en fisiese eienskappe van die vloeiers in ʼn kolom direk beïnvloed, is dit noodsaaklik om gebruik te maak van stelsels met baie min of geen massaoordrag. Dit verseker ʼn akkurate benadering tot die meet van fundamentele hidrodinamiese gedrag. Laastens is gevind dat daar geen hidrodinamiese korrelasies beskikbaar is wat ʼn wye verskeidenheid van kolompakkings, vloeier eienskappe en hidrodinamiese verskynsels onder superkritiese toestande dek nie. Om die tekortkominge in superkritiese hidrodinamika in literatuur aan te spreek, word meer eksperimentele loodsaanlegwerk vereis. Daar is gevind dat geen van die beskikbare loodsaanlegte hidrodinamiese data kan meet nie. Ondersoek is ingestel tot die ombouing van bestaande loodsaanlegte, aanlegte wat gebruik is deur ander navorsingsgroepe en kommersieel beskikbare aanlegte. Daar is tot die gevolgtrekking gekom dat die beste opsie is om ʼn nuwe loodsaanleg self te bou en gebruik te maak van parte uit een van die ou bestaande aanlegte om kostes laag te hou. Sodoende kan ʼn veeldoelige, pasgemaakte loodsaanleg gebou word wat ook vir toekomstige navorsing gebruik kan word. Na ʼn aanvanklike konsep ontwerp vir die nuwe loodsaanleg, is ʼn volledige ontwerp gedoen. Die aanleg bestaan uit twee kolomme van onderskeidelik 17 mm en 38 mm binnedeursnee en 3,5 m en 1,5 m gepakte hoogte, en is in staat om eksperimente by ʼn maksimum druk en temperatuur van tot 300 bar en 200°C uit te voer. Verder is die loodsaanleg in staat daartoe hidrodinamiese data te meet, naamlik die vloeistofophoud in die kolom, drukval oor die kolompakking, kolomvloed en druppel meesleuring. Die vloeistofophoud in die kolom is bepaal deur alle voer tot die kolom te stop en tyd toe te laat vir die vloeistof om te dreineer, waarna die gedreineerde afgetap en gemeet is. Om die drukval te meet word ʼn Endress+Hauser Deltabar S PMD75 DP sel gebruik. Kolomvloed is bepaal met behulp van die drukval oor die kolom en die vloeitempo van die kolom se boonste produkstroom, van waar ʼn hidrodinamies onbruikbare toestand gedefinieer word. Algehele druppel meesleuring, alhoewel onwaarskynlik as gevolg van die teenwoordigheid ʼn ontwasemer in die kolom, is wel ondersoek deur die vloeistofinhoud in die kolom se boonste produkstroom te vergelyk met fase ewewigsdata in literatuur. Voorlopige hidrodinamiese eksperimente is uitgevoer met behulp van die 38mm deursnee kolom gepak met 1/4 " Dixon ringe. Eksperimente is uitgevoer by 120 bar en 40 ° C met 'n CO2 kritiese fase en 'n poliëtileenglikol vloeistof fase met ʼn gemiddelde molêre massa van 400 (PEG 400). Die hidrodinamiese data het verwagte tendense getoon, maar diskrepansies met literatuur waardes. Die verskille tussen die eksperimentele en literatuur data word geregverdig deur die verskille tussen die vloeistowwe, pakking en eksperimentele stelsels wat in die onderskeie studies gebruik is.

Thesis (M.S.)--University of Hawaii, 1966. / Bibliography: leaves [14]-16.

Orientador: Marco Aurelio Cremasco / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-04T19:17:49Z (GMT). No. of bitstreams: 1 Starquit_AxelNicolasVincentReneDesire_M.pdf: 14668743 bytes, checksum: 4db90a43a39b4d77f2e635582b6323b4 (MD5) Previous issue date: 2004 / Resumo: O Brasil é dono de inigualável diversidade biológica, da qual é possível encontrar fármacos de altos valores agregados.A obtenção desses produtos atravessa diversas etapas, desde a identificação de um determinado principio ativo, até a sua recuperação e posterior purificação. São nessas etapas finais que se podem utilizar sistemas de separação baseados na adsorção e, em particular, a técnica cromatográfica de leito móvel simulado (LMS). Na descrição do LMS, é freqüente recorrer à sua modelagem e simulação. Por outro lado, ao se tratar de modelagens rigorosas, estas levam a problemas matemáticos de equações diferenciais parciais acopladas. Tendo em vista a complexidade de tais modelos, resoluções numéricas são necessárias, sendo que o método das colocações ortogonais é o que se encontra com freqüência na literatura para a simulação do LMS. O objetivo desta Dissertação, portanto, é o de desenvolver um método numérico alternativo destinado à resolução do modelo matemático que descreve o fenômeno e a operação do LMS, utilizando-se quatro zonas de separação, cada qual formada por leitos fixos, em sistemas descritos por isotermas lineares. O método matemático proposto é hibrido, comportando parte analítica para o balanço de massa da fase estacionária, a qual é relacionada através do teorema de Duhamel ao balanço de massa da fase móvel que, por sua vez, é resolvido numericamente. O aplicativo computacional desenvolvido foi avaliado por comparação com resultados experimentais advindos da literatura para mistura binária dos aminoácidos fenilalaninae tirosina; para mistura temária desses aminoácidos mais o triptofano e para uma mistura multicomponentes contendo o Pac1itaxel, conhecido como Taxol@, um poderoso agente cancerígeno. Os resultados obtidos demonstraram desempenho satisfatório de método proposto. Além do leito móvel simulado, o aplicativo pode ser avaliado para outros sistemas cromatográficos: curvas de ruptura ("breakthrough") que descrevem a cinética de adsorção em batelada utilizando leito fixo; respostas de pulsos cromatográficos em leito fixo, o que leva às curvas de eluição do pulso. A presente Dissertação de Mestrado foi desenvolvida no Laboratório de Processos em Meios Porosos (LPMP), do Departamento de Termotluidodinâmica (DTF), da Faculdade de Engenharia Química (FEQ),na Universidade Estadual de Campinas (Unicamp) / Abstract: In Brazil, the biodiversity is huge so this country may become one of the greatest bioproducts producers worldwide. When extracted fiom their natural source, those bioproducts are generally obtained in a mixture containing many other compounds, such that, in order to obtain a commercialproduct, the mixture must go through separation and purification processes. In the field of bioprocucts separation, the simulated moving bed process (SMB) has gained much attention since the beginning of the 90th. In modem engineering, modeling and simulating processes has become very common, from the beginning of a new project to the process control in the existing production plants. For simulated moving bed, when rigorous models are used, the model takes the form of a system of coupled partials differentials equations, so that numerical resolutions of the mathematicalproblem are needed. For simulatedmoving bed (SMB) the numerical method of orthogonal collocations is the one most frequently encountered in the literature. This Dissertation presents an altemative numerical method for the simulated moving bed when isotherm can be considered linear. The method proposed, composed of both analytical and numerical schemes which are correlated through Duhamel's theorem, is hybrid. Most of the mass transfer parameters necessary for simulationsare estimated by the use of correlations from literature. Simulation's results for the separation of pharmaceutical's products, using the proposed numerical method, are obtained and compared with experimentalresults fiom literature. Those comparisons demonstrate the validity of the proposed numerical method, showing that it does not induces significant numerical errors, so that one canhave confidence in the results from those simulations.Investigations were also ~ade in order to analyze the influence some of the 5MB operating parameters on the overall equipment' s performances / Mestrado / Engenharia de Processos / Mestre em Engenharia Química

Countercurrent chromatography (CCC) is an advanced liquid-liquid extraction technique that purifies chemical components from complex mixtures. The Brunel CCC' is a J-type centrifuge based upon this technique. This machine can process 5g quantities of sample every 5 hours [Sutherland 1998]. To process 1 tonne of sample per year would require 200 Brunel CCCs, which is not practical as an industrial process. A practical alternative is to use one machine with 200 times the processing capability. To construct such a machine requires a greater understanding of the stationary phase retention inside a coil (column) and the column efficiency (mass transfer between the mobile and stationary phases). This thesis contains research into stationary phase retention. A hypothesis that all J-type centrifuges act as constant pressure drop pumps is proposed. This hypothesis combined with the Hagan-Poiseuille equation for laminar flow produces a theoretical basis for plotting the stationary phase retention against the square root of the mobile phase flow rate as proposed by Du et al [1999]. Supporting experimental evidence is presented showing that the mobile phase flows in a laminar manner and that the pressure drop across a coil is constant for a given set of operating conditions. It is shown that the pressure drop is the same in both normal and reverse phase modes if specific conditions are met. The pressure drop is shown to be independent of tubing bore for helical coils provided that the same helical pitch is used. The experimental results also show how the pressure drop varies with the phase system and rotational speed. Hopefully this is a significant advance in predicting the stationary phase retention of industrial scale J-type centrifuges.

O enriquecimento isotópico de nitrogênio-15 por troca química no sistema NO/HNO3 foi estudado através de duas teorias distintas. Os fatores de fracionamento isotópicos, obtidos pela teoria de contracorrente e os estimados pela teoria da eqüipartição isotópica, foram confrontados através de um modelo. Construiu-se uma coluna de contracorrente, em escala de laboratório, e parâmetros tais como: número de placas teóricas, altura equivalente de uma placa teórica, tipo de enchimento, altura total da coluna, produção de H15NO3/semana, obtidos em condições de equilíbrio dinâmico isotópico, foram estudados comparativamente aos da literatura / Nitrogen-15 isotope enrichment by chemical exchange in NO/HNO3 system was studied using two different theories. The isotope fractionation factors obtained by the countercurrent theory was compared to those estimated by the isotope equipartition theory were confronted through a model. It was built a column in countercurrent at laboratory scale and parameters such as: number of theoretical plates, height equivalent to a H15NO3week, obtained under isotope dynamic equilibrium conditions, were studied in comparison to those in the literature

O enriquecimento isotópico de nitrogênio-15 por troca química no sistema NO/HNO3 foi estudado através de duas teorias distintas. Os fatores de fracionamento isotópicos, obtidos pela teoria de contracorrente e os estimados pela teoria da eqüipartição isotópica, foram confrontados através de um modelo. Construiu-se uma coluna de contracorrente, em escala de laboratório, e parâmetros tais como: número de placas teóricas, altura equivalente de uma placa teórica, tipo de enchimento, altura total da coluna, produção de H15NO3/semana, obtidos em condições de equilíbrio dinâmico isotópico, foram estudados comparativamente aos da literatura / Nitrogen-15 isotope enrichment by chemical exchange in NO/HNO3 system was studied using two different theories. The isotope fractionation factors obtained by the countercurrent theory was compared to those estimated by the isotope equipartition theory were confronted through a model. It was built a column in countercurrent at laboratory scale and parameters such as: number of theoretical plates, height equivalent to a H15NO3week, obtained under isotope dynamic equilibrium conditions, were studied in comparison to those in the literature

Denna studie har utförts på Calamo AB som arbetar med elektropolering och betning av rostfritt stål. Efter ytbehandlingssteget krävs sköljning av godset för att avlägsna kemikalierester vilket medför att stora mängder surt sköljvatten uppstår. Idag används våtkemisk fällningsanläggning för att rena sköljvattnet. Det befintliga reningsverket kräver flertalet tillsatser samtidigt som mängden slam som går till deponi är stor. Företaget vill utreda miljönyttan med att installera en vakuumindunstare för att ersätta det befintliga reningsverket som reningsmetod samt se över möjligheten att minska sin vattenförbrukning i samband med sköljning av gods för att bland annat kunna reducera storleken på indunstaren, minska belastningen på reningsstegen samt reducera mängden avfall. Studiens mål var att kartlägga uppkomsten av förorenat sköljvatten, identifiera potentiella vattenbesparande åtgärder och hur dessa åtgärder påverkar effektiviteten hos reningsanläggningarna. Samt visa hur installation av en vakuumindunstare förändrar företagets miljöpåverkan och utreda om det finns möjligheter att återanvända eller återvinna kemikalier och metaller från processen. Kartläggning och flödesmätningar av sköljvattenbehovet utfördes med hjälp av information av personal på Calamo samt en ultraljudsmätare. Vattenbesparande åtgärder, påverkan på reningsanläggning samt möjligheter till återvinning av kemikalier undersöktes genom litteraturstudie samt modellering i Excel. Utredningen av miljönyttan genom att ersätta befintligt reningsverk med vakuumindunstare utfördes med hjälp av LCA-värden hämtade från databasen SimaPro 8.0.4. Flera olika förslag på vattenbesparande åtgärder studerades och dessa gav en total vattenreduktion till reningsverket på mellan 5 - 81 % beroende på hur många samt vilka åtgärder som vidtogs. Enligt miljöberäkningarna genererar vakuumindunstaren 3 gånger högre utsläpp av koldioxidekvivalenter och 7 gånger större behov av icke förnyelsebar energi jämfört med det befintliga reningsverket. Genom att installera sprutskölj med motströmsteknik i stycke, sammankoppla befintliga sköljkar i avdelningarna betning, AVFKA samt automaten och installera sparsköljstank i alla avdelningar uppnås en reduktion av förorenat vatten till reningsstegen på 81%, vilket ytterligare kan optimeras genom installation av jonbytare, återanvändning av varmt vatten från renrum. Dessutom ökar föroreningshalten med 61% då dessa åtgärder vidtas vilket gynnar reningseffektiviteten i reningsanläggningarna och därav rekommenderas detta alternativ. Även kemikalieanvändningen och förluster av metalljoner reduceras avsevärt i processen genom användningen av sparskölj. Att installera vakuumindunstare rekommenderas inte på grund av dess stora energianvändning, dock kan andra resultat uppstå då andra LCA-värden används samt genom andra antaganden och hänsyn till kemikalie- och metallåtervinning istället för deponi. / This study has been carried out at Calamo AB, which works with electropolishing and pickling of stainless steel. After the surface treatment step, rinsing of the material is required to remove chemical residues, which results in large amounts of acid rinse water. Today, wet chemical precipitation plant is used to clean the rinse water. The existing treatment plant requires most additives, while the amount of sludge that goes to landfill is large. The company wants to investigate the environmental benefits of installing a vacuum evaporator to replace the existing sewage treatment plant as a purification method and to review the possibility of reducing its water consumption in connection with rinsing of goods in order to reduce the size of the evaporator, reduce the load on the purification steps and reduce the amount of waste. The aim of the study was to map the emergence of polluted rinse water, identify potential water-saving measures and how these measures affect the efficiency of the treatment plants. And show how the installation of a vacuum evaporator changes the company's environmental impact and investigate whether there are opportunities to reuse or recycle chemicals and metals from the process. Mapping and flow measurements of the rinse water requirement were performed using information from staff at Calamo and an ultrasonic meter. Water-saving measures, impact on treatment plant and opportunities for recycling of chemicals were investigated through literature study and modeling in Excel. The study of the environmental benefits by replacing existing treatment plants with vacuum evaporators was carried out using LCA values obtained from the database SimaPro 8.0.4. Several different proposals for water-saving measures were studied and these gave a total water reduction to the treatment plant of between 5 - 81% depending on how many and what measures were taken. According to the environmental calculations, the vacuum evaporator generates 3 times higher emissions of carbon dioxide equivalents and 7 times the need for non-renewable energy compared to the existing treatment plant. By installing spray rinse with countercurrent technology in one piece, interconnecting existing rinses in the cuttings departments, AVFKA as well as the dispenser and installing sparse rinse tank in all departments, a reduction of contaminated water to the purification steps of 81% is achieved, which can be further optimized by installation of ion exchangers, reuse of hot water from clean room. In addition, the pollutant content increases by 61% as these measures are taken, which favors the purification efficiency of the treatment plants and hence this option is recommended. The use of chemicals and losses of metal ions are also considerably reduced in the process through the use of savings rinses. Installing vacuum evaporators is not recommended due to its large energy use, however, other results may arise when other LCA values are used, as well as through other assumptions and considerations for chemical and metal recycling instead of landfill.

Simulated moving bed chromatography process (SMBCP) is the technical realisation of a countercurrent adsorption process through the cyclic port switching. SMB technology reduces the cost of packing material with high loading capacity and provides high purity and high recovery in a very short time. Major commodity applications have been found in the petroleum, food, biotechnology, pharmaceutical and fine chemical industries. The industrial applications bring an emergent demand to improve the SMBCP operation for higher product quality, productivity, efficiency and robustness. However, for this particular process, we encounter several challenges. Firstly, the interplay of the effects of strong nonlinearities, competition of solutes, mass transfer resistance and fluid dynamic dispersion produces steep concentration fronts. Mathematical model accounted for this particular property constitutes a serious difficulty for the solution procedure. Secondly, a dynamic SMB model consists of a set of partial differential, ordinary differential and algebraic equations, which are highly coupled. The large size is a problem due to its intensive computation when on-line optimisation and real-time control are necessary. Thirdly, the SMB unit operation exhibits complex dynamics. Process metrics for design and operation can be determined only when a cyclic steady state is reached after a certain number of switching. Achieving this steady state by solving the PDE models cycle after cycle involves expensive calculation. Studies have been carried out to solve these problems through process analysis, investigation on spatial discretisation techniques, and development of an accelerated integration scheme. / Through a systematic study on the advances of SMB modelling, design and control, a set of functionally equivalent models for SMBCP are identified and summarized for their practical applications. The limitations of the existing modelling techniques in industrial applications are also identified. Furthermore, structural analysis of the existing models is conducted for a better understanding of the functionality and suitability of each model. Suggestions are given on how to choose an appropriate model with sufficient accuracy while keeping the computational demand reasonably low for real time control. / Effort is made on to the systematic investigation of different numerical methods for the solution of PDEs to circumvent the steep gradients encountered in chromatographic separation. Comprehensive studies are conducted on a single column chromatographic process represented by a transport-dispersive-equilibrium linear model. Numerical solutions from the upwind-1 finite difference, wavelet-collocation, and high resolution methods are evaluated by quantitative comparisons with the analytical solution for a range of Peclet numbers. It reveals that for a PDE system with a low Peclet number, all existing numerical methods work well, but the upwind finite difference method consumes the most time for the same degree of accuracy of the numerical solution. The high resolution method provides an accurate numerical solution for a PDE system with a medium Peclet number. The wavelet collocation method is capable of catching up steep changes in the solution, and thus can be used for solving PDE models with high singularity. / The advantages and disadvantages of the wavelet based approaches are further investigated through several case studies on real SMBCP system. A glucose-fructose separation process is firstly chosen with its relatively simple isotherm representations. Simulations are conducted using both wavelet collocation and upwind finite difference methods. For more complicated applications, an enantiomers separation process is selected. As the PDEs model exhibit a certain degree of singularity, wavelet collocation and high resolution methods are adopted for spatial discretisation. It is revealed that both the wavelet based approaches and high resolution methods are good candidates in terms of computation demand and prediction accuracy on the steep front. This is the first time that these two frontier numerical methods are used for such a complex SMB system models and our results are encouraging for the development of model-based online control scheme. / In developing a new scheme to rapidly obtain the solution at steady state for any arbitrary initial condition, the concept of Quasi-Envelope (QE) is adopted under the consideration that a SMBCP can be treated as a pseudo-oscillatory process because of a large number of continuous switching. The scheme allows larger steps to be taken to predict the slow change of starting state within each switching. Combined with previously developed wavelet-based technique, this method is successfully applied to the simulation of a SMB sugar separation process. Investigations are also carried out on the location of proper starting point for the algorithm and on the effect of changing stepsize to the convergence of iteration method. It is found that if the starting state of Quasi-Envelope is chosen to be the same as the original function, the multivalue algorithm would require similar computational effort to achieve the steady state prediction, regardless of the integration stepsize. If using constant stepsize, launching QE later is helpful when quasi-envelope displays steep change at the start-up period. A changing stepsize produces slow convergence compared to the constant stepsize strategy, thus increasing the work load where the stepsize change is occurring. Other iteration method is required to be imposed to achieve faster convergence right from the beginning. Potential applications can be seen for other chemical engineering processes with inherent cyclic behaviour.