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Shi, Ruijie. "Subspace identification methods for process dynamic modeling /". *McMaster only, 2001.
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Narisaranukul, Narintr. "Modeling and analysis of the chemical milling process". Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/43425.
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Sinangil, Mehmet Selcuk. "Modeling and control on an industrial polymerization process". Thesis, Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/10150.
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Johnston, Lloyd Patrick Murphy. "Probability based approaches to process data modeling and rectifictaion". Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/10913.
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Koulouris, Alexandros. "Multiresolution learning in nonlinear dynamic process modeling and control". Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/11376.
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Bohn, Douglas (Douglas Gorman) 1970. "Computer modeling of a continuous manufacturing process". Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/47557.
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Thesis (S.M.)--Massachusetts Institute of Technology, Sloan School of Management; and, Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 1998.Includes bibliographical references.
by Douglas Bohn.
S.M.
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Lai, Jiun-Yu. "Mechanics, mechanisms, and modeling of the chemical mechanical polishing process". Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/8860.
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Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2001.Includes bibliographical references.
The ever-increasing demand for high-performance microelectronic devices has motivated the semiconductor industry to design and manufacture Ultra-Large-Scale Integrated (ULSI) circuits with smaller feature size, higher resolution, denser packing, and multi-layer interconnects. The ULSI technology places stringent demands on global planarity of the Interlevel Dielectric (ILD) layers. Compared with other planarization techniques, the Chemical Mechanical Polishing (CMP) process produces excellent local and global planarization at low cost. It is thus widely adopted for planarizing inter-level dielectric (silicon dioxide) layers. Moreover, CMP is a critical process for fabricating the Cu damascene patterns, low-k dielectrics, and shallow isolated trenches. The wide range of materials to be polished concurrently or sequentially, however, increases the complexity of CMP and necessitates an understanding of the process fundamentals for optimal process design. This thesis establishes a theoretical framework to relate the process parameters to the different wafer/pad contact modes to study the behavior of wafer-scale polishing. Several models of polishing - microcutting, brittle fracture, surface melting and burnishing - are reviewed. Blanket wafers coated with a wide range of materials are polished to verify the models. Plastic deformation is identified as the dominant mechanism of material removal in fine abrasive polishing.
(cont.) Additionally, contact mechanics models, which relate the pressure distribution to the pattern geometry and pad elastic properties, explain the die-scale variation of material removal rate (MRR) on pattern geometry. The pad displacement into low features of submicron lines is less than 0.1 nm. Hence the applied load is only carried by the high features, and the pressure on high features increases with the area fraction of interconnects. Experiments study the effects of pattern geometry on the rates of pattern planarization, oxide overpolishing and Cu dishing. It was observed that Cu dishing of submicron features is less than 20 nm and contributes less to surface non-uniformity than does oxide overpolishing. Finally, a novel in situ detection technique, based on the change of the reflectance of the patterned surface at different polishing stages, is developed to detect the process endpoint and minimize overpolishing. Models that employ light scattering theory and statistical treatment correlate the sampled reflectance with the surface topography and Cu area fraction for detecting the process regime and endpoint. The experimental results agree well with the endpoint detection schemes predicted by the models.
by Jiun-Yu Lai.
Ph.D.
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Bakshi, Bhavik Ramesh. "Multi-resolution methods for modeling, analysis and control of chemical process operations". Thesis, Massachusetts Institute of Technology, 1992. http://hdl.handle.net/1721.1/13203.
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Bryden, Michelle D. (Michelle Denise). "Macrotransport process in branching networks : modeling convective-diffusive phenomena in the lung". Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/33514.
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Ji, Qingjun. "Mathematical modeling of carbon black process from coal". Ohio : Ohio University, 2000. http://www.ohiolink.edu/etd/view.cgi?ohiou1172255200.
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Hanes, Rebecca J. "Multidisciplinary modeling for sustainable engineering design and assessment". The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1437204293.
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Bieszczad, Jerry 1971. "A framework for the language and logic of computer-aided phenomena-based process modeling". Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/16735.
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Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 2000.Includes bibliographical references (p. 273-277).
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Chemical process engineering activities such as design, optimization, analysis, control, scheduling, diagnosis, and training all rely on mathematical models for solution of some engineering problem. Likewise, most of the undergraduate chemical engineering curricula are model-based. However, the lack of formalization and systematization associated with model development leads most students and engineers to view modeling as an art, not as a science. Consequently, model development in practice is usually left to specialized modeling experts. This work seeks to address this issue through development of a framework that raises the level of model development from procedural computations and mathematical equations to the fundamental concepts of chemical engineering science. This framework, suitable for implementation in a computer-aided environment, encompasses a phenomena-based modeling language and logical operators. The modeling language, which represents chemical processes interms of interacting physicochemical phenomena, provides a high-level vocabulary for describing the topological and hierarchical structure of lumped or spatially distributed systems, mechanistic characterization of relevant phenomena (e.g., reactions, equilibria, heat and mass transport), and thermodynamic and physical characterization of process materials. Thelogical operators systematize the modeling process by explicitly capturing procedural and declarative aspects of the model ingactivity.
(cont.) This enables a computer to provide assistance for analyzing and constructing phenomena-based models, detect model inconsistencies and incompleteness, and automatically derive and explain the resulting model equations from chemical engineering first principles. In order to provide an experimental apparatus suitable for evaluating this framework, the phenomena-based language and logical operators have been implemented in a computer-aided modeling environment, named MODEL.LA. MODEL.LA enables phenomena-based modeling of dynamic systems of arbitrary structure and spatial distribution, hierarchical levels of detail, and multicontext depictions. Additional components allow incorporation of thermodynamic and physical property data, integration of control structures, operational task scheduling, and external models,and assistance for specification and solution of the resulting mathematical model. Application of this environment to several modeling examples, as well as its classroom and industrial deployment, demonstrate the potential benefits of rapid, reliable, and documented chemical process modeling that may be realized from this high-level phenomena-based approach.
by Jerry Bieszczad.
Ph.D.
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Miller, Neidi. "Process design and modeling for the production of triacylglycerols (TAGs) in Rhodococcus opacus PD630". Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/70461.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 2012."February 2012." Cataloged from PDF version of thesis.
Includes bibliographical references (p. 32-34).
The oleaginous microorganism Rhodococcus opacus PD630 was used to study the characteristics and kinetics of the accumulation of triacylglycerols (TAGs) in cells. In this process, accumulation of TAG is stimulated when a carbon source is present in the medium in excess and the nitrogen source is limiting growth. Under controlled fermentation conditions the organism Rhodococcus opacus PD630 has been shown to grow to high cell density, producing high yields of TAGs (above 50% of cell dry weight) in a relatively short period of time. In this study, the reaction stoichiometry was established and the carbon balance for the process has been effectively closed, accounting for approximately 91% of the total carbon in the system. Several fed-batch strategies were explored at the IL benchtop bioreactor scale. Feeding both carbon and ammonium sulfate as the nitrogen source can sustain cell growth but was found to significantly obstruct the accumulation of TAGs. While these fed-batch strategies did not lead to titer improvements, they did highlight the significance of TAG degradation for growth. To aid in future process design strategy optimization an unstructured kinetic model was developed to describe the dynamics of the fermentation of Rhodococcus opacus PD630 and its triacylglycerol (TAG) production. The kinetic parameters for this model were either measured from experimental data or estimated by fitting the experimental data using least-squares non-linear regression. Global minimum of the sum of squared errors (SSE) between the model prediction and various experimental data sets was found by an iterative process of parameter space exploration. The minimum SSE obtained was 91.229. The proposed model is the first step towards understanding and optimizing the process of lipid production and accumulation in oleaginous organisms.
by Neidi Miller.
S.M.
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Wise, Barry Mitchell. "Adapting multivariate analysis for monitoring and modeling of dynamic systems /". Thesis, Connect to this title online; UW restricted, 1991. http://hdl.handle.net/1773/9860.
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Darira, Rishi. "Modeling demand uncertainty and processing time variability for multi-product chemical batch process". [Tampa, Fla.] : University of South Florida, 2004. http://purl.fcla.edu/fcla/etd/SFE0000401.
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Pattalachinti, Ravi Kumar. "Modeling and optimization of continuous melt-phase polyethylene terephthalate process". Ohio : Ohio University, 1994. http://www.ohiolink.edu/etd/view.cgi?ohiou1178728743.
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Gopalakrishnan, Varsha. "Nature in Engineering: Modeling Ecosystems as Unit Operations for Sustainability Assessment and Design". The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1500460468877501.
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Khorami, Hassan. "Multivariate Modeling in Chemical Toner Manufacturing Process". Thesis, 2013. http://hdl.handle.net/10012/8012.
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Process control and monitoring is a common problem in high value added chemical manufacturing industries where batch processes are used to produce wide range of products on the same piece of equipment. This results in frequent adjustments on control and monitoring schemes. A chemical toner manufacturing process is representative of an industrial case which is used in this thesis. Process control and monitoring problem of batch processes have been researched, mostly through the simulation, and published in the past . However, the concept of applying the subject to chemical toner manufacturing process or to use a single indicator for multiple pieces of equipment have never been visited previously.
In the case study of this research, there are many different factors that may affect the final quality of the products including reactor batch temperature, jacket temperature, impeller speed, rate of the addition of material to the reactor, or process variable associated with the pre-weight tank. One of the challenging tasks for engineers is monitoring of these process variables and to make necessary adjustments during the progression of a batch and change controls strategy of future batches upon completion of an existing batch. Another objective of the proposed research is the establishment of the operational boundaries to monitor the process through the usage of process trajectories of the history of the past successful batches.
In this research, process measurements and product quality values of the past successful batches were collected and projected into matrix of data; and preprocessed through time alignment, centering, and scaling. Then the preprocessed data was projected into lower dimensions (latent variables) to produce latent variables and their trajectories during successful batches. Following the identification of latent variables, an empirical model was built through a 4-fold cross validation that can represent the operation of a successful batch.
The behavior of two abnormal batches, batch 517 and 629, is then compared to the model by testing its statistical properties. Once the abnormal batches were flagged, their data set were folded back to original dimension to form a localization path for the time of abnormality and process variables that contributed to the abnormality. In each case the process measurement were used to establish operational boundaries on the latent variable space.
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He, Qinghua Qin S. Joe. "Innovative techniques for industrial process modeling and monitoring". 2005. http://repositories.lib.utexas.edu/bitstream/handle/2152/1564/heq44479.pdf.
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He, Qinghua. "Innovative techniques for industrial process modeling and monitoring". Thesis, 2005. http://hdl.handle.net/2152/1564.
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Gautami, G. "Modeling and simulation of multiple effect evaporator system". Thesis, 2011. http://ethesis.nitrkl.ac.in/4417/1/main_copy_to_CD(PDF).pdf.
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In the present work a mathematical model based on set of nonlinear equations has been developed for synthesis of multiple effect evaporator (MEE) systems. As evaporator house is one of the most energy intensive units of pulp and paper industries, different configurations are considered in the model to reduce the energy consumption. These are condensate, feed and product flashing, vapor bleeding, steam splitting, etc. Along with these the present model also accounts the complexities of real MEE system such as variable physical properties, boiling point rise. Along with complexities discussed above, the present model also accounts the fouling resistance. For this purpose a linear correlation is developed to predict fouling resistance based on velocity as well as temperature difference. The fouling resistance observed by this correlation is within the limit shown in the literature (Muller-Steinhagen and Branch, 1997). It reduces overall heat transfer coefficient by 11.5% on average.For the present study two MEE systems of typical Indian pulp and paper industries are considered. First MEE system selected for modeling and simulation is seven effect evaporator system located in north India which is being operated in a nearby Indian Kraft Paper Mill for concentrating weak black liquor using plate falling film evaporators. This system employs steam splitting in first two effects, feed and product flashing along with primary and secondary condensate flashing to generate auxiliary vapor, which are then used in vapor bodies of appropriate effects to improve overall steam economy of the system. The second system used for present study is located in south India. It is ten effect evaporator system used for concentrating black liquor and being operated in mixed flow sequence. In this system feed and steam splitting as well as vapor bleeding is employed.For seven effect evaporator system total fourteen models are developed. Initially, a simplest model without any variation is derived based on mass and energy balance. Further, it is improved by incorporating different configurations such as variation in physical properties, BPR, steam splitting, feed, product and condensate flashing and vapor bleeding. These models are developed with and without fouling resistance.The governing equations of these models are nonlinear in nature. Further, it is observed that for these models the number of equations as well as the number of variables are equal and hence unique solution exist for all cases. The set of nonlinear algebraic equations are solved using software called ‘system of non linear equations’. However, in the present work to incorporate the complex interactions of variables during solution of model an iterative procedure is used.For seven effect evaporator system total 14 models are proposed to visualize that how individual configuration is affecting the steam economy of the MEE system. The comparison shows that maximum steam economy is observed for the model where flashing as well as vapor bleeding are used. In comparison to the simplest system the improvement in steam economy through best model is found as 27.3%. The modified seven effect evaporator system, obtained using best model, requires four shell and tube heat exchangers and five pumps. This modification has total capital investment as Rs 29.3 lakh. However, saving in steam consumption is found as Rs 21.8 lakh/year thus, total payback period for the modified seven effect evaporator system is 1.3 years. For ten effect evaporator system improvement in steam economy is observed by 12.8% in comparison to existing system. It incorporates three preheaters which use bled vapor from the system. Based on the comparison with published model as well as industrial data it is found that the present model can be effectively applied to simulate the real MEE system and improve the steam economy of MEE system by 15%.
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Saturnino, Daniel M. "Modeling of Kraft Mill Chemical Balance". Thesis, 2012. http://hdl.handle.net/1807/32881.
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The reduction of mill effluent discharge as a result of stringent environmental legislations can have a significant impact on sodium (Na) and sulfur (S) balances in the kraft pulping process. In order to maintain a proper balance of Na and S, kraft mills may need to adopt different makeup strategies. For this purpose, a dynamic model was developed to predict the Na and S balance in the kraft recovery cycle, as well as the accumulation of undesirable non-process elements such as chlorine (Cl) and potassium (K).
The model was developed using the CADSIM software and was validated using data obtained from a Brazilian bleached kraft pulp mill. The calculated data from the model showed good agreement with mill data with respect to all parts of the mill simulated. Dynamic tests designed to calculate the white liquor sulfidity over specific periods of time also presented good agreement. The result indicates that the model is able to describe the balance of chlorine, potassium, sodium and sulfur in the kraft process.
A study conducted to evaluate the Cl and K accumulation agrees with the expected behaviour observed in mill data. The presence of ash treatment systems allow to reduce Cl and K contents in recovery boiler precipitator ash from 4.2 mol% Cl(Na+K) to 1.25 mol % and from 2.25 mol % K/(Na+K) to 0.8 mol% for 100% ash treated. The tests performed for Na and S balances focused in the makeup requirement for two situations: ash purging and ash treatment to control Cl and K levels. The use of ash treatment systems reduced Na and S makeup requirement from 5 to 50% depending on the amount of ash treated.
A simple mathematical model was then used to estimate the Cl balances around the recovery cycle. Given that the proper simplifications are applied, the CADSIM model and the CSTR model presented good agreement in estimating the Cl balances. This result provided not only another method for the CADSIM model to be validated but also a way to calculate a rough estimate for Cl balance.
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Noh, Kyungyoon, Jiun-Yu Lai, Nannaji Saka i Jung-Hoon Chun. "Mechanics,Mechanisms and Modeling of the Chemical Mechanical Polishing Process". 2002. http://hdl.handle.net/1721.1/4032.
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The Chemical Mechanical polishing (CMP) process is now widely employed in the Integrated Circuit Fabrication. However, due to the complexity of process parameters on the material removal rate (MRR), mechanism of material removal and pattern effect are not well understood. In this paper, three contact regimes between the wafer surface and the polishing pad were proposed: direct contact, mixed or partial contact, and hydroplaning. The interfacial friction force has been employed to characterize these contact conditions. Several polishing models are reviewed with emphasis on the mechanical aspects of CMP. Experiments have been conducted to verify the mechanical polishing models and to identify the dominant mechanism of material removal under typical CMP conditions.Singapore-MIT Alliance (SMA)
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Saleh, Abdullah. "Study Of The Performance Of Batch Distillation Using gPROMS". Thesis, 2011. http://ethesis.nitrkl.ac.in/2625/1/final_Thesis.pdf.
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The detailed dynamic modelling,and simulation of a batch distillation process is presented. The model considers a mixture of 5 components separated in a 20 tray column. Simulations performed in the process modelling tool gPROMS proved that the model gives a very accurate description of the process behaviour. Overall, gPROMS proved to be a powerful tool for solving problems of large scale models of great complexity such as the batch distillation process. One of the reasons for this is its ability to model and handle discontinuities of the types that very often occurs in chemical processes (for example, when changing the reflux ratio during a distillation operation). As with any other chemical process, the modelling of batch distillation requires the accurate consideration of physical properties in order to model the thermodynamics of the process in an accurate manner.
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Kumar, Sushil. "Life Cycle Assessment of the Process Steam Reforming of Methane(SMR)". Thesis, 2015. http://ethesis.nitrkl.ac.in/7981/1/2015_Life_Kumar.pdf.
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Life cycle assessment is a process to determine the environmental impact of the product at various stages of its life during the process. The steam reforming of methane is carried out in a methane reformer using ASPEN PLUS simulator at 630 ºC temperature and 1.5 atm pressure. Methane at these conditions reacts with steam to produce Carbon dioxide (CO2), Carbon monoxide (CO) and Hydrogen (H2). The tress amount of Carbon monoxide is also converted to Carbon dioxide in two steps; High temperature shift conversion (HTS) and Low temperature shift conversion (LTS). Methyl diethanolamine (MDEA) is utilized to retain carbon dioxide from the final stream. Life cycle assessment is then carried out to find the effect of Carbon dioxide gas in air emission, Greenhouse effect, Energy consumption and Waste water emission at different stages of the process. The outcome demonstrates the increment in weight (%) of CO2.
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Parihari, Arati. "Performance Study of Spray Dryer Using Various Salt Solutions". Thesis, 2009. http://ethesis.nitrkl.ac.in/165/1/Arati.pdf.
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Spray drying is an essential unit operation for the manufacture of many products with specific powder properties. It is characterized by atomization of a solution or suspension into droplets, followed by subsequent drying of these droplets by evaporation of water or other solvents. Spray drying is used for the manufacture of many consumer and industrial products such as instant food products, laundry detergents, and pharmaceuticals. It is well suited to continuous production of dry solids in powder, granulate or agglomerate particle form from liquid feed-stocks. Spray drying starts with the atomization of a liquid feedstock into a spray of droplets. Next, the droplets are put in contact with hot air in a drying chamber. The sprays are produced by either rotary (wheel) or nozzle atomizers of different types. Evaporation of moisture from the droplets and formation of dry particles proceed under controlled temperature and airflow conditions. Powder is continuously discharged from the drying chamber and recovered from the exhaust gases using a cyclone or a bag filter. The whole process generally takes no more than a few seconds. Correct atomization and air distribution are the keys to the spray drying process, as both greatly influence the final powder structure and quality. Often, spray dryers are equipped with high-speed centrifugal atomizers ensuring sturdy and reliable operation. High-Pressure nozzle atomization is used especially for products where a rather coarse powder with narrow particle distribution and high bulk density is required. In the nozzle atomizer, fines are returned around one or more central nozzles in order to facilitate optimum agglomeration. Two-Fluid nozzle agglomeration is typically applied in small chambers allowing maximum flexibility in particle design and particle engineering for both super-fine and agglomerated particles.
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Mahapatra, Dibya Lochan. "Modeling of Fluid Phase Equilibria by PC-Saft EOS: Solubility of Gases/Vapor in Polythylene". Thesis, 2009. http://ethesis.nitrkl.ac.in/352/2/skmaity.pdf.
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The prediction or correlation of thermodynamic properties and phase equilibria with equations of state remains an important goal in chemical and related industries. Although the use of equations of state has for a long time has been restricted to systems of simple fluids, there is an increasing demand for models that are also suitable for complex and macromolecular compounds. Due to its ability to describe the thermodynamics of symmetric as well as asymmetric systems, the most common approaches for modeling gas-polymer solubility have been based on the PC-SAFT EOS. It has wide applicability starting from low molecular weight organic compounds to highly non-ideal macro-molecular weight system such as polymer In the present work, PC-SAFT equation of state of Gross & Sadowski, 2001 has been used to model solubility of various gases /vapors in liquid polyethylene to demonstrate the suitability of PC-SAFT EOS for polymer-solvent system.
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Maity, S. K. "Modeling and Simulation of Solid-Liquid Equilibrium by Perturbed-Chain Statistical Associating Fluid Theory". Thesis, 2003. http://ethesis.nitrkl.ac.in/1325/1/MTech-Thesis.pdf.
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Solubility of polyethylene in mixed xylene was determined experimentally at atmospheric pressure by an indigenously developed laser based technique. In this work, PC-SAFT equation of state was used to model solid-liquid equilibrium (SLE). With the experimental SLE data available in literature for low molecular weight n-alkanes and aromatic compounds both at atmospheric and elevated pressure, the suitability of the developed SLE model based on PC-SAFT equation of state was tested. Subsequently a sensitivity study was performed to understand the effects of different parameters that affect the solubility of polyethylene. The validated model was then used to correlate the experimentally determined solubility data for polyethylene system.
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Kumar, Ashish. "Development of Mixed Integer Non-Linear Model for Hydrogen Distribution in them Refinery". Thesis, 2009. http://ethesis.nitrkl.ac.in/1040/1/Ashish.pdf.
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In the refining industry, growing amount of hydrogen is needed for petroleum conversion and clean fuel production. The design of hydrogen networks in industrial production sites aims at minimizing the consumption of fresh hydrogen by optimizing the operating parameters, more and more by trying to recycle the degraded hydrogen produced in the process units, and by integrating hydrogen purification units.
For this purpose Pinch Technology, linear model, nonlinear model is obtained in terms of flow rates and purities of streams handled by compressors and purifiers. The optimal design of hydrogen networks aims at minimising the consumption of fresh hydrogen by improving recycling and reuse of process hydrogen. In the literature this was achieved by LP and NLP models which computed the minimum hydrogen requirement, and made a preliminary selection of the compatible purification units. These models also integrated compressor units.
In the present work the distribution of hydrogen is carried out by MILP (Mixed integer linear programming) model which is solved by mathematical programming software GAMS. The detail modeling and solution techniques are discussed in the report. Along with this, some excel data sheets are provided which shows how the calculations were done in LP and NLP model . The results obtained from present study compare well with the published work. Further, some suggestions are given for future research.
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Javaji, S. K. "Study of Dynamic Behavior of Ethyl Acetate Reactive Distillation Column Using ASPEN PLUS". Thesis, 2009. http://ethesis.nitrkl.ac.in/1532/1/10500022.pdf.
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Reactive distillation (RD), the combination of chemical reaction and distillation in a single unit operation, has proven to be advantageous over conventional process systems consisting of separate reactor and distillation units. But the dynamic behavior of process is difficult to study. In this thesis, a reactive distillation column for ethyl acetate production has been created in ASPEN user interface. Steady state simulations are done in ASPEN user interface and the effect of reflux ratio on the composition of ethyl acetate in the distillate is studied. In ASPEN DYNAMICS the composition control studies for ethyl acetate purity has been studied both in the distillate and in the bottoms.
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Mahapatra, N. "Design and Simulation of Cumene Plant using Aspen Plus". Thesis, 2010. http://ethesis.nitrkl.ac.in/1746/1/nirlipt_ethesis.pdf.
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Cumene production process is gaining importance and so the process needs to be studied and better ideas suggested such that the production cost is reduced. With the advent of computers and simulating software like ASPEN PLUS® it is possible to design and optimize a particular process. Proper design can significantly reduce production cost as well as provide make the process safe and reduce environmental hazards. It has been identified from previous research papers that the cost of materials used is much higher than the cost of energy needed for the process. The materials, unit operations and processes involved are identified. Steady state simulation is done. Each unit is taken into consideration and the variables are optimized. The units are sequentially optimized in the order in which they appear in the rough flow sheet. Use of newer equipments in the process is suggested. The reactor system on being optimised by an equilibrium based approach gave the operating temperature as 360 C and 6:1 Benzene: Propylene ratio in feed. The distillation columns were optimised and the number of trays for benzene column was found to be 20 by 8 and that for cumene column to be 20 by 10. The reflux ratio values were found to be 0.5 and 0.8 respectively for the columns. The optimised temperature for flashing was identified as 92.5 C. The modified flow sheet of the optimised process was prepared which gives the values of all the optimised variables in detail.
Keywords: Simulation, Optimization, Cumene, Benzene, distillation, reactor
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Kumar, S. "Modelling and Simulation of Ethyl Acetate Reactive Distillation Column using ASPEN PLUS". Thesis, 2010. http://ethesis.nitrkl.ac.in/1944/1/3-joined.pdf.
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In this thesis, we study the modeling and simulation of a reactive distillation column for the production of ethyl acetate from acetic acid and ethyl alcohol using ASPENPLUS. Starting from a conventional configuration, which involves feeding in a single tray, different configuration is proposed and various specifications are studied for the attainment of higher conversion and purity at the steady state. In ASPEN DYNAMICS an analysis of the column dynamics is then performed. Cascade control structure is studied for the base design.
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M, A. Kumar. "Modelling the Hydrodynamic Characteristics of Gas-Liquid-Solid Fluidized Bed using Artificial Neural Networks". Thesis, 2010. http://ethesis.nitrkl.ac.in/1945/1/FINAL_THESIS.pdf.
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Gas–liquid–solid fluidized beds are used extensively in the refining, petrochemical, pharmaceutical, biotechnology, food and environmental industries. The fundamental characteristics of a three-phase fluidized bed have been recently studied extensively. The reviews indicate the importance of the information of phase holdup and bed voidage characteristics, in the optimal design of a three-phase fluidized bed reactor.
The various hydrodynamic parameters of three phase fluidized bed have been modeled using Artificial Neural Networks (ANNs). ANNs are good at modeling of non linear parameters, with the ability to generalize the relationships among the data. The data for developing the models has been generated using various correlations available from literature. These correlations are valid for different ranges of the variables. So, artificial neural networks are trained using this vast data range and a generalized model for the hydrodynamic parameters is developed.
This project report can be divided mainly into three parts. The first part discusses about importance of gas-liquid-solid fluidized bed, their modes of operation, important hydrodynamic properties those have been studied either related to modeling and applications of gas-liquid-solid fluidized bed. The second part gives an overview of the basics of Artificial Neural Networks (ANNs) and the various architectures of neural networks that are commonly used for modeling. The third part consists of the details of the problem description and the approach used by ANN to model the hydrodynamic characteristics. The results show that the model has been effective in generalizing the relationship of various hydrodynamic characteristics with their respective independent variables.
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Modi, Sourav. "Application of UNIQUAC model in modeling VLE of acid gas aqueous alkanolamine system". Thesis, 2011. http://ethesis.nitrkl.ac.in/2577/1/combine.pdf.
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The removal of acidic gases like Carbon Dioxide and Hydrogen sulphide from gas streams is a very important operation in natural gas and synthetic ammonia industries, petrochemical plants and oil refineries. For this purpose absorption with aqueous solutions of alkanolamines is being
used. The objective is to develop a thermodynamic VLE model in order to calculate the equilibrium distribution of ionic and molecular species in the highly non-ideal liquid phase. This thesis is a work on the application of the UNIQUAC model in modeling VLE of acid gas alkanolamine system.
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Barman, Ghanshyam. "Congo Red (cr)Removal from Aqueous Solution by Commercial and Laboratory Prepared Low Cost Adsorbents Using Adsorption". Thesis, 2011. http://ethesis.nitrkl.ac.in/3019/1/CONGO_RED__CR__REMOVAL_FROM_AQUEOUS_SOLUTION_BY_COMMERCIAL_AND_LABORATORY_PREPARED_LOW_COST_ADSOR.pdf.
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Release of dyes into the environment from industrial practices is a matter of global concern.Dyes are emitted from industrial plants in the form of aqueous effluents. They are widely used in several industries like textile, dyeing, paper and pulp, tannery, paint industries etc.Dyes are considered an objectionable type of pollutant because they are toxic in nature. Their classification can be done based on their usage, group and solubility. Various treatment processes used for the removal of dyes include adsorption, microbial degradation, wet air oxidation, etc. Use of commercial and low cost adsorbents is a viable option for dyes removal from aqueous effluents. However, high cost of commercial adsorbents like activated carbon and others, and material losses during their regeneration pose an impediment in the utilization of commercial adsorbents. This has led to a search for cheaper alternative materials as adsorbents such as lignin, bagasse pith, peat, saw dust; coal fly ash; rice husk ash and Bio-fuel extract (BFE), etc. The present study is therefore, aimed to study the process of adsorption of Congo red (CR) onto powdered and granular-activated carbon (PAC & GAC),and indigenously prepared low-cost adsorbents such as Bagasse fly ash (BFA), Rice husk ash (RHA), coconut Ash (CCA), Fruit juice extract (FJE), BAEL (Aegle marmelos) and spent tea (ST) and to find out the possibility of using them as low-cost adsorbents for the removal of dyes in general and CR in particular.This investigation also examines the influence and optimization of various process parameters for their optimal performance
such as initial concentration of CR (C0) contact time (t), temperature (T), and initial pH of dye solution. Batch adsorption experiments for the removal of CR from the aqueous solution by PAC, GAC, BFA, RHA, CCA, FJE, BAEL and ST were performed by using Taguchi design methodology.
Factors as such pH, temperature, adsorbent dose and contact time were optimized with the bigger-isbetter S/N ratio as quality characteristics and analysis of variance with 25 sets of experiments only. The optimum CR removal experimental conditions are obtained for all the adsorbents used with respect to their maximum uptake capacities in the present work. Moreover, the adsorbents were also characterized for their valuable adsorbable properties like surface area and point of zero charge.
The exhausted low-cost adsorbents along with the sorbed CR can be separated from the solution (by filtration), dried and used as such or as fire briquettes to recover their energy value. The resulting bottom ash blended with cementations mixture can be used for making building blocks or it may be used to make fire bricks.
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Moghekar, Deepak. "Project Report On Modeling and simulation of gas-liquid interfacial area in three phase fluidized and semi-fluidized bed". Thesis, 2008. http://ethesis.nitrkl.ac.in/4317/1/d.pdf.
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Three phase systems are vital part of chemical industry,as reactions involving gas, liquid solid are often encountered in chemical process industry [Yatish Shah 2000]. The most common occurrence of this type of three phase systems is in hydro processing industry in which variety of reactions between hydrogen and oil phase and solid catalyst have been found. The other common three phase reactions are catalytic oxidation and hydration reactions These and other numerous similar gal-liquid–solid reactions are carried out in reactors. The three-phase system is subcategorized as
• Reactions where the gas, liquid and solid are either reactants or products
• Gas-Liquid reactions with solid as a catalyst.
• Two reaction phases and third as inert phase.
• All three phases are inert as found in unit operations.
Examples of first two types can be found very often in chemical process
industry, as each phase is essential in the reaction mechanism. In the third type, one
inert phase in especially added to get the advantage of three-phase system. The third
inert phase induces better momentum exchange between the phases, helps in better
distribution of reactant species and good temperature control. The filtration
operation can be example of fourth type of three phase system
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Tripathi, Nagesh Kumar. "Production, Purification and Characterization of Recombinant Viral Proteins". Thesis, 2012. http://ethesis.nitrkl.ac.in/4452/1/Full_PhD_Thesis-508CH802.pdf.
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Dengue fever, a mosquito-borne viral disease has become a major worldwide public health problem with a dramatic expansion in recent years. Similarly, Japanese encephalitis (JE) is one of the leading causes of acute encephalopathy affecting children and adolescents in the tropics. There is neither an antiviral therapy nor any effective vaccine available for dengue. Early diagnosis plays a crucial role to forecast an early warning of epidemic and to undertake effective vector control measures for dengue and Japanese encephalitis. Envelope domain III (EDIII) protein is involved in binding to host receptors and it contains specific epitopes that elicit virus neutralizing antibodies. The objective of the present work is to develop high yield and scalable production process for recombinant dengue and Japanese encephalitis envelope domain III proteins in Escherichia coli, purification process to achieve high purity and biologically active protein as well as their characterization for use as diagnostic reagent in enzyme linked immunosorbent assay (ELISA) and possible vaccine candidate molecule. Expression of EDIII proteins of JE and Dengue viruses was carried out in recombinant Escherichia coli. Developments of cost effective and simple culture media as well as appropriate culture conditions are generally favorable for large scale production of recombinant proteins. Optimization of culture media was carried out for enhanced production of EDIII protein in E. coli. Laboratory scale batch fermentation process in E. coli was developed using optimized media and culture conditions. Furthermore, fed-batch fermentation process was also developed in optimized medium. Expression of this protein in E. coli was induced with isopropyl β-D-thiogalactoside. The protein was overexpressed in the form of insoluble inclusion bodies (IBs). Cells were disrupted using sonicator or agitator bead mill and IBs were purified. For diagnostic studies, the protein was purified under denaturing conditions using affinity chromatography. The affinity chromatography purified protein was used as an antigen to develop enzyme linked immunosorbent assay (ELISA) to detect antibodies in infected serum and CSF samples. In order to take this vaccine candidate for further studies, recombinant EDIII protein was produced employing a pilot scale fermentation process. Recombinant EDIII protein expressed as inclusion bodies was solubilized in the presence of urea and renatured by oncolumn refolding protocol in the presence of glycerol. A three-step purification process comprising of on-column refolding with affinity chromatography, ion-exchange chromatography (IEX) based on salt, and IEX based on pH was developed. The purity of the recombinant EDIII protein was checked by sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis, and reactivity of this protein was determined by Western blotting and ELISA. Biological function of the refolded and purified EDIII protein was confirmed by their ability to generate EDIII-specific antibodies in mice that could neutralize the virus. These findings suggest that recombinant EDIII protein is highly immunogenic and elicit high-titer neutralizing antibodies. These results establish the application of these proteins to be used for the diagnosis of JE and Dengue virus infection or for further studies in vaccine development. This process may also be suitable for the high-yield production of other recombinant viral proteins.
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Ray, Minaketan. "Synthesis and characterization of AgBr/SiO2 core/shell nanoparticles". Thesis, 2012. http://ethesis.nitrkl.ac.in/4461/1/Thesis_18.12.12-pdf-_MKRAY.pdf.
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In the recent years there is tremendous demand of smaller devices over the bigger one because of its efficiency and portability. The nanoparticles are the building blocks to make the very small devices like small robot, micro-motor, small chips, microprocessor, sensor or carrier for drugs or storage for fuel cell etc. So small is not only beautiful but also powerful.
To improve the property of nanoparticle, composite or core/shell nanoparticles are synthesized. The core-shell nanoparticles are used in the field of biotechnology for drugs carrier, in electronic as semiconductor materials, in fuel-cell and also in chemical reaction. The easy and generalization of methods is required to prepare the core-shell nanoparticles. In this study we prepared core-shell nanoparticles, where AgBr is core and silica as a shell material. For preparation of core-shell nanoparticles, precipitation and the modified Stöber method were adopted. The surfactant is used to modify the surface of core particle so that core-shell nanoparticle will form. Before going to core-shell particles, the individual particles of AgBr and SiO2 were studied. Spherical AgBr nanoparticles were prepared in aqueous media in the absence and presence of surfactant. Smaller particles were obtained in pure aqueous media by increasing the reactant concentration. The coarsening rate constant for the particle formation was found to increase linearly with increasing reactant concentration. The presence of nonionic surfactant generated smaller particles than were obtained in pure aqueous media. The coarsening rate constant in the presence of TX-100 was always lower than that in the presence of pure aqueous media. In pure aqueous media, the temperature effect caused an increase in particle size as the temperature was increased from 20 to 30 °C, after which the change was not significant. In contrast, in the presence of TX-100, the change was not significant in the 20 - 30 °C temperature ranges, but a further increase to 40 °C resulted in a significant change in size. Silica is coated on AgBr nanoparticles by modified Stöber methods. The lowest particles size of the AgBr/SiO2 core-shell was 90±8 nm. The core-shell particle sizes varied from 95 nm to 430 nm. It is found that the bigger particle size found on higher concentration of TEOS. The CTAB surfactant assist-AgBr nanoparticles were isolated in silica shell, indicates CTAB concentration (0.1 mM) were optimal for the formation of monolayered structures on AgBr surfaces. The shell thickness was very thin 5 nm. The AgBr/SiO2 core/shell nanoparticles have been prepared within 100 nm by modified Stöber methods. The spherical composite materials are formed. The shell thickness can be controlled on varying the concentration of precursor’s solution. Silica can be coated on other material by modifying the surface of the core shell materials.
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Biswal, Nihar Ranjan. "Studies on Adsorption and Wetting Phenomena Associated with Solid Surfaces in Aqueous Synthetic and Natural Surfactant Solutions". Thesis, 2012. http://ethesis.nitrkl.ac.in/4464/1/Nihar_R_Biswal_thesis_1-1-13.pdf.
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Adsorption of surfactants at air-liquid and solid-liquid interface and wetting of solid surfaces are closely interdependent. The performance of many physicochemical process and fundamental understanding depends on these two important phenomena. Because of the importance of these phenomena this study mainly focuses on adsorption of different surfactants at air-water and solid-water interfaces and wetting of those surfactant solutions at flat solid surfaces. The main emphasis of this study is plant-based natural surfactants; however some synthetic surfactants are also studied as a reference for comparison. The effects of electrolytes, alcohols, and naturalsynthetic surfactants mixtures are also studied. Electrolytes are most powerful inexpensive additive enhances the adsorption capacity of ionic surfactants at interfaces which in turn also enhances the interfacial behaviour. Adsorption kinetics and isotherm of anionic (dodecylbenzene sulfonate, SDBS), cationic (cetylpyridinium bromide, CPB), and non-ionic (TX-100) surfactants in the presence and absence of electrolytes on PTFE-water interface are studied. The kinetics of adsorption fits well pseudo-second-order kinetic model for the three surfactants studied here. Adsorption isotherms of TX-100 follow Langmuir type, whereas SDBS and CPB follow Freundlich type. However, in the presence of electrolytes both the ionic surfactants show better fitting with Langmuir type isotherm. The effect of electrolytes on the surfactant concentration far below the CMC shows there is a linear increase in amount adsorbed with the increase in ionic strength of the electrolyte mainly due to reduction in headgroup repulsion and finally reaches a plateau level when the equilibrium concentration reaches CMC at that electrolyte concentration. The structure of tailgroup of non-ionic surfactants also plays an important role in both adsorption and wetting behaviour. To get some insight about the fact, the adsorption and wetting behavior of two nonionic surfactants (TX-100 and Igepal CO-630) having the same headgroup but structurally different tailgroups has been compared. The change in contact angle with the concentration of surfactant follows a trend similar to that for adsorption onto a PTFE surface. At low surfactant concentration, Igepal CO-630 shows a slightly higher adsorption density and better wetting properties than TX-100. Both surfactants show lower adsorption densities at the PTFE–water interface than at the air–water interface.
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Garapati, Vamsi Krishna. "Biodegradation of Petroleum Hydrocarbons". Thesis, 2012. http://ethesis.nitrkl.ac.in/4467/1/Vamsi_Thesis.pdf.
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Biodegradation of hydrocarbons in the environment is the natural way of cleaning the nature. The potential biodegradation of hydrocarbon contaminants by microorganisms is dependent on the environmental factors and the nutrients available. In this study culture conditions like temperature, pH, and nitrogen source were optimized by conventional one-factor at a time experimentation and the combination of other nutrients (nitrogen, phosphorus,
magnesium, and sulfur) was optimized by using design of experiments (DOE) combined with grey relational analysis (GRA). Total petroleum hydrocarbons of oil sludge, light crude oil and heavy crude oil, degradation was studied for a period of thirty days using microbial strains isolated from the hydrocarbon contaminated sites. They have shown predominant results in the degradation of TPH’s under optimized culture conditions and prior addition of biosurfactants in the culture flask has enhanced the degradation process and microbial biomass yield.
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Mishra, Sambhurisha. "Hydrodynamic Studies of Three-Phase Fluidized Bed by Experiment and CFD Analysis". Thesis, 2013. http://ethesis.nitrkl.ac.in/4598/1/Mtech(R)_Thesis-610ch304.pdf.
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The complex hydrodynamics of three-phase (gas-liquid-solid) fluidized beds are not well understood due to complicated phenomena such as particle-particle, liquid-particle and particle-bubble interactions. In the present work both experimental and computational studies have been carried out on two and three dimensional fluidized beds to characterize there hydrodynamic behavior. Air, water and low density solid particles have been used as the gas, liquid and solid phase to analyze the system behaviors. Eulerian multi-phase model has been used to simulate the system by using the commercial CFD code ANSYS Fluent 13.0. Gidaspow and Schiller-Neumann drag models have been used to calculate inter-phase drag force. Two-equation standard k-ε model has been used to describe the turbulent quantities. CFD simulation of three-phase fluidized bed systems with a distributor plate is not seen in literature. In the present work fluidized bed with distributor having orifice diameter 0.002 m has been studied. Result obtained from the simulation shows that fluidized bed with distributor has higher values of bed expansion and gas holdup compared to that of fluidized bed without distributor plate. It is also observed that in the bed having distributor the velocity magnitudes of solid particles, the liquid and gas phases are high and more fluctuating than in the bed without distributor. Simulation result obtained from CFD simulation with low density solid material is found agree with the experimental finding.
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Singh, Anil Kumar. "Classification of Flow Regimes Using Linear Discriminant Analysis (LDA) and Support Vector Machine (SVM)". Thesis, 2013. http://ethesis.nitrkl.ac.in/4750/1/211CH1040.pdf.
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This dissertation project presents a novel method for the classification of vertical and horizontal two-phase flow regimes through pipes. For gas-liquid vertical and horizontal two-phase flows, the goal of the study is to predict the transition region between the flow regimesusing the data generated by empirical correlations. The transition region is determined with respect to pipe diameter, superficial gas velocity, and superficial liquid velocity. Accurate determination of the flow regime is critical in the design of multiphase flow systems, which are used in various industrial processes, including boiling and condensation, oil and gas pipelines, and cooling systems for nuclear reactors.
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Ansari, Mazhar Husain. "Simulation of effects of various parameters in solid waste gasification in a fixed bed reactor". Thesis, 2013. http://ethesis.nitrkl.ac.in/5253/1/109CH0494.pdf.
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With the enormous amount of solid waste being produced on a daily basis in different municipal corporations, its usage as another form of valuable raw material for the production of combustible fuel is of great interest to the scientific community. The solid waste can be treated appropriately for the generation of clean fuel, as well as it reduces the burden to dispose of the material in a environment friendly manner. Thus the extraction of all the valuable gases from the solid waste which can help in meeting the ever rising energy demands. Our model is based on the fixed bed type of reactor, the simulation of which is done using the very dynamic and useful software- Aspen plus. The fixed bed used here is an updraft type one with the following section: Drying, Pyrolysis, Gasification and Combustion. The performance of the reactor is to be investigated for carbon conversion at different gasification temperature, pressure, air equivalence ratio, and heat conversion efficiencies.
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Arora, S. "Simulation study of divided wall distillation column". Thesis, 2014. http://ethesis.nitrkl.ac.in/5970/1/E-137.pdf.
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These days the center is on energy-saving advances. Several techniques have been proposed inorder to improve the efficiency of distillation process; dividing-wall column is one of thesetechniques. Conventionally, distillation columns are connected in series to separatemulti-component mixtures into more than two product streams with high purity prerequisites. However, in the dividing-wall column, middle section is divided into two sections by inserting avertical wall in the vessel at an appropriate position. Feed is introduced into the pre-fractionatorside of the wall. A side stream is removed from the main column. Therefore, a single dividingwall column can separate a ternary mixture into three pure product streams. The side stream ismostly the intermediate boiling component of the ternary mixture.In the present study a mathematical model of the dividing wall column has been developed,which incorporates the material balance, energy balance, and equilibrium relationships. This model was simulated by taking four columns in an equivalent divided wall distillation column sequence using aspen Plus. This particular design was used to study the separation of three ternary mixtures, Benzene-Toluene-P-Xylene, Benzene-Toluene-O-Xylene and Methanol- Water-Glycerol. The effects of several parameters suchas reflux ratio, number of trays, feed composition, and splitting ratio have been discussed to findthe optimum operating conditions.
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Mohanty, V. "Simulation of methyldiethanolamine-carbon dioxide-water system using equilibrium approach". Thesis, 2014. http://ethesis.nitrkl.ac.in/5972/1/E-139.pdf.
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As the climate is changing very frequently and global warming is increasing at an alarming rate, there is a need to mitigate greenhouse gases which have gained a top most priority. As the main source of CO2 emission is fossil fuels (mainly in power plants), there is a need to keep check on utilization of fossil fuels. Carbon capture and sequestration (CCS) is one of the methods which enable the utilization of fossil fuels with lower CO2 emissions. Commercially CO2 capture by chemical absorption is very active. While number of solvents for CO2 absorption by chemical method has been proposed, comparison on performance of different solvents has not been done properly and claims on different solvent vary widely. The work done here emphasize on absorption of CO2 by the solvent and then stripping the solvent to obtain pure CO2.This thesis has been prepared to evaluate the performance of solvent – methyldiethanolamine(MDEA) on CO2 absorption. In this thesis, comprehensive flow sheet model has been built for the solvent system, using ASPEN Plus as the modeling tool. The Thermodynamic model using ENRTL model for CO2 capture has been done and effect of reboiler duty, solvent flow rate and so on has been observed.
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Mishra, D. P. "Simulation of carbon dioxide - monoethanolamine - water system using equilibrium approach". Thesis, 2014. http://ethesis.nitrkl.ac.in/5974/1/e-141.pdf.
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Carbon Dioxide is a greenhouse gas and has been identified as the prime source of global warming and climate changes. So the major challenge ahead of us is the capture and removal of CO2. Though there are different methods and technologies available, the most efficient method is the use of an absorption/stripping process with a chemical solvent for absorption. Various solvent have been tried, but aqueous monoethanolamine remains the most common and popular solvent. This thesis focuses on the development of a comprehensive flowsheet based on the thermodynamic model which assumes the overall process to be at equilibrium. The ASPEN PLUS software was used for developing and simulating the problem. The Electrolyte–NRTL model was chosen as the base method with ensured the use of predefined physical properties, thermodynamics and kinetics for the simulation of the process. Once the simulation is over and it properly converges giving an acceptable capture percentage , sensitivity analysis were carried out to study and get an rough idea about the nature and extent of the effect of different parameters on the reboiler duty or energy requirement and other properties like amine flow rate . The simulation based on thermodynamic model is the stepping stone for the more complex and tedious rate based studies as its gives us an estimate of different properties and constraints.
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Pati, A. "Simulation and modelling of divided wall distillation column by programming design equations using MATLAB". Thesis, 2014. http://ethesis.nitrkl.ac.in/5975/1/E-142.pdf.
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The thesis describes about the simulation and design study of divided wall distillation columns using various mathematical models. Since all of us are aware, that distillation is the fundamental aspect of separation processes in the Chemical industries. In the current thesis, simulation studies of the divided wall distillation column using various mathematical models are presented. Steady state simulations are being performed using Thomas mathematical model supported by rigorous programming using combination of MATLAB which is the fundamental programming language In the steady state simulation we have tried to see the effect of changing the number of plates on the component mole fraction, vapor flow rate, liquid flow rate, Temperature etc., which gives an idea about the optimum number of plates in the divided wall distillation column. The basic input variables used are tear variables i.e. temperature and vapor flow rate. Firstly, MESH equations has been written for an equilibrium stage in a multi-component vapor liquid cascade. Those equilibrium stages can be combined to form a counter-current cascade of N equilibrium stages that can be used to model divided wall distillation column. Then the mathematical model of tri-diagonal matrix algorithm has been applied to solve the MESH equations. And then rigorously solving countercurrent-flow, multi-equilibrium stage, multi-component separation system with the help of Thomas algorithm and with the help of a process simulator. And thereby by rigorous programming and continuous simulation it predicts optimum number of plates alongside implementation of controllability factors could be implemented for feasible operation of divided wall distillation column. Thus, designing of divided wall distillation column must be encouraged in chemical industries reducing two important parameters cost and energy to a great extent thereby enhancing profitability of the industries to a great extent.
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Sambit, S. "Simulation and flow analysis through a straight pipe". Thesis, 2014. http://ethesis.nitrkl.ac.in/5977/1/E-144.pdf.
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In this study, the frictional losses in a pipe due to shear stress produced in a pipe due to viscosity of fluids has been discussed. Pipeline system in India is a vast network and minimizing losses through these pipes can contribute a lot to the country. This paper contains flow analysis of different fluids in a pipe. The simulations were done using ANSYS FLUENT CFD 14.0 software to observe pressure drops between inlet and outlet of a pipe. Pressure Difference and frictional coefficient were calculated using Darcy-Weisbach equation. The model used in ANSYS FLUENT CFD 14.0 is a 3 dimensional model through which different fluids were made to pass through and subsequent analysis were done. The paper also includes comparison of results obtained from practical methods, theoretical methods and ANSYS. The flow is considered to be turbulent and open channel flow.
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Agarwal, A. "Separation of azeotropic mixture by extractive distillation and pressure-swing distillation:computer simulation and economic optimization". Thesis, 2014. http://ethesis.nitrkl.ac.in/5983/1/E-150.pdf.
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The Separation of Di-n-propyl ether and n-propyl alcohol is difficult because the highly non-ideal vapour-liquid equilibrium forms a azeotrope. It is very difficult to separate the azeotropic mixture by ordinary processes of distillation. The most common methods for separating the azeotropic mixture are pressure swing distillation and extractive distillation process. Pressure swing distillation is a better process for the case where the azeotropic composition changes significantly with the change in pressure whereas the extractive distillation process is effective only if we are able to find a suitable solvent. This thesis equates these two different process to separate the mixture consisting of 50-50 mole % of di-n-propyl ether and n-propyl alcohol by means of a practical case of a industry. We have studied and simulated these two separate alternatives of the mixture for the case of a plant to treat 12000 Tm/year of the original mixture. The simulation is carried out satisfactorily by means of a package of commercial software i.e. Aspen Plus using the thermodynamic model UNIQUAC with the help of other parameters obtained. Aspen plus is a very important tool for the simulation of various processes with different thermodynamic models. In the result we have calculated different parameters required such as number of plates, feed plate etc. We have also calculated the amount of heat required for the reboiler and the cooling required in the condensers. We have also calculated the reflux ratio and the graph between the reflux ratio and the no. of stages is plotted. We have also simulated the stream results required for the valves and the mixer. The pump efficiency electricity required and the pressure drop across the pump has also been accounted.
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Patra, R. "Rate studies on monoethanolamine-carbon dioxide-water system". Thesis, 2014. http://ethesis.nitrkl.ac.in/6070/1/E-193.pdf.
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Owing to the increase in Green House Gases in the atmosphere, the most widely known Global Warming, in the present scenario, is inevitable. Thus, to mitigate the comparatively larger amount of these gases, various scientific and technological developments have been ensured. Carbon Capture & Storage (CCS) technique helps in this regard to lessen the amount of CO2 in the atmosphere by absorbing CO2 in a suitable absorbent and then stripping it from that absorbent in the subsequent process to get almost pure CO2, which is stored and used for its many industrial applications. Amongst the sources of CO2, Natural Gas Power Plant, Coal-fired Power Plant and Nuclear Power Plant are of prime concern to subject our problems and project a solution. Although having a different prospects and methods of CO2 capture, CCS by Chemical Absorption Method (Post-Combustion) can be viewed as a commercial approach to have a large scale application. For this, although a large number of solvent along with their blends has been experimented, a systematic theoretical as well as realistic practical approach on many of the solvent and the comparison between them has yet not been performed. Again, where many of the literature review shows VLE studies on the respective solvents; very few of them have revealed a significant approach on Rate Studies. This thesis is about ensuring a more practical approach to determine the performance of the solvent MEA (Monoethanol Amine) in CO2 absorption in Rate Model using ASPEN PLUS.