The Experts below are selected from a list of 207 Experts worldwide ranked by ideXlab platform
Amiya K Jana - One of the best experts on this subject based on the ideXlab platform.
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Vertical partition in fractionating tower to configure a novel heat integrated distillation hybridized with Vapor recompression
Separation and Purification Technology, 2020Co-Authors: Amiya K JanaAbstract:Abstract This work aims at introducing the Vapor recompression (VRC) mechanism in a novel divided-wall heat integrated distillation column (HIDiC). To generate an internal heat source and utilize it in an optimal way, the cylindrical shell of the distillation column is proposed to divide by a metal wall into two semi-cylinders to operate within the HIDiC framework. This divided-wall HIDiC leads to exchange the heat between two diabatic sections, thus reducing the external supply of thermal utilities in both the reboiler and condenser. Introducing thermal coupling further between the Overhead Vapor of high pressure (HP) column (i.e., right semi-cylinder) and the reboiler content of low pressure (LP) column (i.e., left semi-cylinder) under the framework of VRC scheme, the resulting Vapor recompressed divided-wall HIDiC shows its potential in further cutting the utility consumption and cost. Using two performance indicators, namely energy savings and total annual cost (TAC) or equivalent payback period, the performance improvement achieved through the proposed heat integrations is quantified through a simulated multicomponent reactive distillation.
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Bottom flashing with interreboiling action in a transient batch rectifier: Economic feasibility, dynamics and control
Separation and Purification Technology, 2017Co-Authors: Amiya K JanaAbstract:Abstract This work aims at proposing a batch rectifier with bottom flashing (BRBF) scheme, in which, a fraction of reboiler content is dynamically flashed to lower its temperature so that the exiting liquid can be used as a heat sink against the Overhead Vapor (heat source) in the condenser. Receiving latent heat from that Vapor, the flashed liquid gets Vaporized and merges with the flashed Vapor. Recovering pressure of this combined stream, it is used as a boil-up Vapor in the reboiler, thus lowers the external heat duty. By this way, the proposed BRBF arrangement reduces the utility consumption in both the reboiler and condenser. To improve the energetic potential further, the boil-up Vapor produced in the flashing loop is proposed to split into a couple of fractions and distributed in intermediate stage(s) along with the reboiler. The BRBF coupled with this interreboiling action is subjected to economic feasibility test, for which, the concerned column configurations need to be dynamically close, if not same. Since the batch processing is inherently a transient operation, it is not trivial to have their dynamics close. To make the comparison meaningful, we formulate an open-loop control scheme that makes sure that the BRBF follows the conventional batch rectifier (CBR) dynamics, which is used as a basis. Finally, a binary system is simulated to demonstrate the proposed BRBF with and without interreboiling. It is investigated that the BRBF configuration provides an about 68% energy savings with a payback time of 3 yr. Further, proposing interreboiling in the BRBF column increases the energy savings to 81%, reducing the payback time to 2.32 yr.
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Dynamic Vapor recompression in a reactive batch rectifier: Analysis and nonlinear control
Energy, 2016Co-Authors: Sudip Banerjee, Amiya K JanaAbstract:Abstract This work proposes a dynamic Vapor recompressed batch reactive rectifier (VRBRR) for the butyl acetate system that operates with a dynamic compression ratio (CR). In this configuration, along with the CR, we manipulate either the Overhead Vapor inflow rate to the compressor or the external heat input to the reboiler for the purpose of coupling the thermal arrangement with the existing batch tower. To improve the product purity and the amount of distillate collection of the dynamic VRBRR, we further formulate a nonlinear extended generic model controller (EGMC) that requires state information for its simulation. For this, we develop a closed-loop high gain observer (HGO) for estimating a limited number of states, exclusively required for the EGMC. This results in a significant structural mismatch that is taken care of by the hybrid EGMC-HGO system. For the representative butyl acetate system, it is investigated that the proposed nonlinear controller outperforms a traditional PI controller in regulating the dynamic VRBRR.
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Assessing the performance improvement of an intensified heat integration scheme: Reactive pressure-swing distillation
Applied Thermal Engineering, 2015Co-Authors: Bandaru Kiran, Amiya K JanaAbstract:Abstract Declining petroleum reserves, increasing fuel demands and environmental problems have attracted increasing research attention in improving the energetic potential of separation processes dominated by distillation. In this contribution, we develop an intensified thermal integration scheme for a pressure-swing distillation (PSD) by combining the internally heat integrated distillation column (HIDiC) and the Vapor recompression column (VRC), thereby acquiring the benefit of both of them. Since the PSD process typically combines a low-pressure (LP) and a high-pressure (HP) distillation unit, the possibility of thermal coupling arises between the HP column (heat source) and the LP column (heat sink) within the framework of HIDiC scheme. Aiming to further reduce the consumption of external energy in the PSD system, the Overhead Vapor of HP column is proposed to act as a heat source for bottom liquid reboiling in the LP column by the application of VRC mechanism. By this way, the HIDiC-VRC combination gets the shape of an intensified structure and it is capable of providing an enhanced energy efficiency potential. For a reactive pressure-swing distillation (reactive PSD), the proposed HIDiC-VRC configuration is shown to be more energy efficient and cost-effective compared to the HIDiC-alone scheme.
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A novel combination of internal and external heat integrations in batch distillation: Application to a reactive system
Applied Thermal Engineering, 2013Co-Authors: Debadrita Maiti, Amiya K JanaAbstract:Abstract Studies on the thermal integration of batch rectifier have received almost no attention, although it is well-known for continuous distillation since the 1960s. In this contribution, we aim to develop an energy integration approach for batch distillation columns by thermally coupling the rectification tower with the concentric reboiler that surrounds the tower as a jackted. In this internally heat integrated batch distillation with a jacketed reboiler (IHIBDJR), the Vapor produced in the concentric reboiler is compressed and then it enters the bottom of the rectifier. With the judicious use of internal heat source, the proposed IHIBDJR shows its attractiveness in terms of energy savings and payback time of excess capital. The pressure elevation from the jacketed reboiler to rectifying section generates a possibility of further intensification through the introduction of direct Vapor recompression mechanism in the IHIBDJR. This novel combination of internal and external heat integrations can utilize the latent heat, an additional internal source, released by the compressed Overhead Vapor in Vaporizing the reboiler liquid. After deriving the general form of this combined heat integrated structure, the mechanism is finally illustrated by a batch reactive distillation. This hybrid configuration shows promising energetic and economic potential over the IHIBDJR and its conventional counterpart.
William L. Luyben - One of the best experts on this subject based on the ideXlab platform.
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High-pressure versus low-pressure auxiliary condensers in distillation Vapor recompression
Computers & Chemical Engineering, 2019Co-Authors: William L. LuybenAbstract:Abstract A recent paper studied the separation of ethylene and ethane using several types of distillation systems in which cryogenic cooling is required. The economics of a conventional column using a very low-temperature expensive refrigerant in the condenser were compared with several configurations using process compressors. The alternative configurations involve the pressure in the auxiliary condenser and the fraction of the column Overhead Vapor sent through the compressor. Low pressure in the condenser requires a very low-temperature expensive refrigerant but has lower compressor costs. The purpose of this paper is to show that all of the Vapor from the column should be compressed and then split, with some going to the reboiler and the rest going to an auxiliary condenser that operates at high pressure so that a higher-temperature less-expensive refrigerant can be used.
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Improved control structure for extractive divided-wall column with Vapor recompression
Chemical Engineering Research and Design, 2019Co-Authors: William L. LuybenAbstract:Abstract A novel process for ethanol dehydration using extractive distillation in a modified divided-wall column has been proposed and its control studied. A single vessel is used to perform the tasks of pre-concentrating the dilute feed, producing high-purity water and ethanol products and recovering the ethylene glycol solvent. Feed is introduced on one side of the wall that receives no liquid from the rectifying section. Water is removed from bottom of this side that has an intermediate reboiler, which is heated by compressed Overhead Vapor. Ethanol is the distillate product and solvent comes out the bottom of the column to be fed near the top of the column. A complex control structure has been proposed that appears to lack robustness since it can only handle slow ramp disturbances. This paper demonstrates that a more simple control structure can provide effective regulatory control for large step changes in throughput and feed composition.
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Control of an azeotropic DWC with Vapor recompression
Chemical Engineering and Processing - Process Intensification, 2016Co-Authors: William L. LuybenAbstract:Abstract The use of Vapor recompression in a complex divided wall column (DWC) configuration for heterogeneous azeotropic distillation has been shown to provide steady-state economic advantages over conventional designs. The two segregated stripping sections in the DWC are separated by a wall and each has a reboiler. The column has a rectifying section whose Overhead Vapor is split into two streams. One goes to a condenser. The other goes to a compressor whose high-pressure outlet stream provides heat to one of the reboilers. The other reboiler is heated by steam. The two condensed Overhead streams are fed to a decanter. The organic phase is refluxed to the top of the column. The aqueous phase is recycled by combining with the fresh feed. The dynamic controllability of this highly heat integrated and interacting process is studied in this paper. A detailed dynamic simulation is constructed, and an effective control structure is developed that handles large disturbances in throughput and feed composition. The numerical example considers the dehydration of tert-butanol using cyclohexane as the entrainer in heterogeneous azeotropic distillation.
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A Comprehensive Real-World Distillation Experiment.
Chemical engineering education, 2015Co-Authors: Christos G. Kazameas, Kaitlin N. Keller, William L. LuybenAbstract:Most undergraduate mass-transfer and separation courses cover the design of distillation columns, and many undergraduate laboratories have distillation experiments. In many cases, the treatment is restricted to simple column configurations and simplifying assumptions are made so as to convey only the basic concepts. In industry, the analysis of a real operating distillation column is a very important issue in terms of improving performance (maximizing capacity, minimizing energy consumption, etc.). Few of the simplifying assumptions apply, and a rigorous analysis is required to achieve accurate results. This paper discusses a distillation experiment that brings out many important practical aspects of using operating data from a typically complex distillation process to assess performance. The complexities include an economizer (feed preheated by Overhead Vapor), non-optimum feed tray location, inefficient trays, subcooled reflux and subcooled feed. Experimental results are compared to the predictions of computer simulations. Both total reflux operation and normal operation with feed and product streams are explored. One of the most important concepts derived from the experiment is how to startup the process.
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Design and Control of Stacked-Column Distillation Systems
Industrial & Engineering Chemistry Research, 2014Co-Authors: William L. LuybenAbstract:The separation of close-boiling, low-relative volatility components by distillation requires many trays and high reflux ratios (high energy consumption). Temperature-sensitive components often limit temperatures, so vacuum conditions must be used in which pressure drop through trays or packing becomes very important. More trays produce higher base pressures and higher base temperatures for a given pressure in the reflux drum. Therefore, it may be impossible to achieve the desired separation in single column if the maximum temperature limits the number of trays. In this situation, multiple columns must be used to stay within the feasible number of trays per vessel. Each column has its own condenser and reboiler. The bottoms from the upper column is fed to the top of the lower column, and the Overhead Vapor from the lower column is condensed, pumped to a higher pressure, and fed into the base of the upper column. This stacked column configuration has high energy and capital cost, but it may be the only feas...
Debadrita Maiti - One of the best experts on this subject based on the ideXlab platform.
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A novel combination of internal and external heat integrations in batch distillation: Application to a reactive system
Applied Thermal Engineering, 2013Co-Authors: Debadrita Maiti, Amiya K JanaAbstract:Abstract Studies on the thermal integration of batch rectifier have received almost no attention, although it is well-known for continuous distillation since the 1960s. In this contribution, we aim to develop an energy integration approach for batch distillation columns by thermally coupling the rectification tower with the concentric reboiler that surrounds the tower as a jackted. In this internally heat integrated batch distillation with a jacketed reboiler (IHIBDJR), the Vapor produced in the concentric reboiler is compressed and then it enters the bottom of the rectifier. With the judicious use of internal heat source, the proposed IHIBDJR shows its attractiveness in terms of energy savings and payback time of excess capital. The pressure elevation from the jacketed reboiler to rectifying section generates a possibility of further intensification through the introduction of direct Vapor recompression mechanism in the IHIBDJR. This novel combination of internal and external heat integrations can utilize the latent heat, an additional internal source, released by the compressed Overhead Vapor in Vaporizing the reboiler liquid. After deriving the general form of this combined heat integrated structure, the mechanism is finally illustrated by a batch reactive distillation. This hybrid configuration shows promising energetic and economic potential over the IHIBDJR and its conventional counterpart.
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Intensified thermal integration in batch reactive distillation
Applied Energy, 2013Co-Authors: Debadrita Maiti, Amiya K Jana, Amar Nath SamantaAbstract:Published work on the heat integration of batch distillation is scare and mainly focuses on the continuous flow columns. This paper introduces a novel thermally integrated batch reactive distillation, in which, the rectification tower runs as usual at atmospheric pressure and the concentric reboiler operates under vacuum. It is inspected that the proposed thermally integrated batch reactive distillation with a concentric vacuum reboiler secures positive savings of energy and better economic figures than the conventional batch reactive distillation. Importantly, this scheme has the potential to enhance the product purity at steady state by the improvement of reaction conversion. For boosting both the energetic and economic performance of the proposed thermally integrated batch distillation scheme, in this contribution, we introduce further intensification by coupling the Overhead Vapor and the reboiler liquid.
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Improving energy efficiency and cost-effectiveness of batch distillation for separating wide boiling constituents. II: Internal versus external heat integration
Chemical Engineering and Processing: Process Intensification, 2013Co-Authors: Amiya K Jana, Malik Nawaz Khan, Debadrita MaitiAbstract:Abstract In the first paper of this series, we developed a Vapor recompressed batch distillation (VRBD) scheme by means of external heat integration. This contribution aims at devising an internally heat integrated batch distillation with a concentric reboiler (IHIBDCR) configuration, in which the rectifying tower is surrounded by a jacket. The operating cost can be reduced with the improvement of energy savings substantially through seeking further external heat integration under the framework of Vapor recompression mechanism in the IHIBDCR structure between the Overhead Vapor and the reboiling liquid. The features of both the IHIBDCR system and its hybrid form that combines the Vapor recompression column (VRC) and the IHIBDCR scheme are illustrated by a binary mixture having wide boiling constituents, with special emphasis focused on the comparative performance study between the externally integrated VRBD presented in Part 1 of the current work, the internally integrated IHIBDCR arrangement and the hybrid structure.
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An ideal internally heat integrated batch distillation with a jacketed still with application to a reactive system
Energy, 2013Co-Authors: Amiya K Jana, Debadrita MaitiAbstract:Abstract Batch distillation is an irreversible process and consumes many times the theoretical minimum energy requirement. The present work focuses on the development of an internally heat integrated batch distillation with a jacketed still (IHIBDJS) aiming to reduce the degree of irreversibility towards zero. The IHIBDJS scheme consists of a rectifying tower equipped with an Overhead condenser and a still pot or reboiler that surrounds the tower concentrically. For improving the energy efficiency by the reduction of external energy input, the rectifier is operated at an elevated pressure so that a thermal driving force should exist between the rectifying tower and the concentric still. For this purpose, an isentropic compression system is mounted in the reboiled Vapor line. Aiming to reduce further the degree of process irreversibility, we propose an additional thermal arrangement into the IHIBDJS configuration that couples the Overhead Vapor with the reboiler liquid, thereby reducing further the external heat consumption. It is investigated for a reactive batch distillation column that the effective use of internal heat sources would make the heat integrated column an independent scheme of external heat source.
Litao Jia - One of the best experts on this subject based on the ideXlab platform.
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Two-Stripper/Flash/Distillation Column System Design, Operation, and Control for Separating 2-Pentanone/4-Heptanone/Water Azeotropic Mixture via Navigating Residue Curve Maps and Balancing Total Annual Cost and Product Loss
Industrial & Engineering Chemistry Research, 2018Co-Authors: Ming Xia, Hui Shi, Congbiao Chen, Yong Xiao, Bo Hou, Litao JiaAbstract:A novel method for the synergetic production of 2-pentanone and 4-heptanone has been explored recently at the Institute of Coal Chemistry, Chinese Academy of Sciences (ICC, CAS). The collected mixture, containing mainly 2-pentanone/4-heptanone/water/carbon dioxide, presents heterogeneous azeotropes. The separation of this quaternary mixture is the main problem urgently to be effectively solved. In this work, a two-stripper/flash/column flow sheet is proposed to achieve the separation, in which the heterogeneity of the system is fully utilized by using an Overhead Vapor–liquid–liquid (VLL) flash. A general total annual cost (GTAC) for balancing total annual cost (TAC) and product loss (PL) is proposed as an optimization function, and several optimization sequences are presented to facilitate the optimization. Four candidate sequences (S1, S2, S3, and S4) are derived from navigating the ternary and residue curve maps, of which the S4 cuts the GTAC with a marked margin (83.9%) compared with the S1. The rigor...
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Two-Stripper/Flash/Distillation Column System Design, Operation, and Control for Separating 2‑Pentanone/4-Heptanone/Water Azeotropic Mixture via Navigating Residue Curve Maps and Balancing Total Annual Cost and Product Loss
2017Co-Authors: Ming Xia, Hui Shi, Congbiao Chen, Yong Xiao, Bo Hou, Litao JiaAbstract:A novel method for the synergetic production of 2-pentanone and 4-heptanone has been explored recently at the Institute of Coal Chemistry, Chinese Academy of Sciences (ICC, CAS). The collected mixture, containing mainly 2-pentanone/4-heptanone/water/carbon dioxide, presents heterogeneous azeotropes. The separation of this quaternary mixture is the main problem urgently to be effectively solved. In this work, a two-stripper/flash/column flow sheet is proposed to achieve the separation, in which the heterogeneity of the system is fully utilized by using an Overhead Vapor–liquid–liquid (VLL) flash. A general total annual cost (GTAC) for balancing total annual cost (TAC) and product loss (PL) is proposed as an optimization function, and several optimization sequences are presented to facilitate the optimization. Four candidate sequences (S1, S2, S3, and S4) are derived from navigating the ternary and residue curve maps, of which the S4 cuts the GTAC with a marked margin (83.9%) compared with the S1. The rigorous economic design and optimum operation of the flow sheet are further investigated in detail. Moreover, several control structures (TCS1, TCS2, and DTCS, CTCS, C&TCS) are successively explored with consideration of ordinary-purity and high-purity separations. Dynamic control shows that whereas the flow sheet can be controlled by controlling one tray temperature in each stripper/column for ordinary-purity separation, an expensive and high-maintenance online composition control should be considered for high-purity separation
Xigang Yuan - One of the best experts on this subject based on the ideXlab platform.
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novel eco efficient Vapor recompression assisted arrangement for minimum boiling side stream pressure swing distillation system preheating feed stream to dew or bubble point
Separation and Purification Technology, 2021Co-Authors: Shunjin Yang, Qingjun Zhang, Xigang Yuan, Aiwu ZengAbstract:Abstract In this paper, a novel eco-efficient intensified Vapor recompression-assisted arrangement is developed for side-stream pressure-swing distillation (SSPSD) configuration with the ethyl-acetate and ethanol separation as the illustrative example. The special characteristics for this novel system are that the feed streams are preheating to their dew points through condensing some portion flow of energy-elevated Overhead Vapor stream from high-pressure column and another is used to boilup the bottoms in reboiler. The economically optimal process is the novel Vapor recompression-assisted SSPSD arrangement (NVRC1-SSPSD-HEN) with heat exchanger network (designed by the Aspen Energy Analyzer based on the pinch technology) wherein only the high-pressure column takes this novel option. Compared to the optimal self-heat recuperative arrangement of preheating feed streams to their bubble points (VRC-SSPSD4-HEN), it can achieve the reductions of 18.81% (77.83%) in energy consumption rates, 27.97% (91.69%) in CO2 emissions, and 3.75% (27.80%) in total annual cost (TAC) as well as an enhancement of 23.61% (336.93%) in thermodynamic efficiency. The data in brackets refer to the basic SSPSD case. The main advantage of this novel process is concentrated on reducing energy consumption, especially of electricity consumption, and the 15.72% less in compressor power is achieved in this novel proposed system.
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Improving performance of dividing wall column using multistage Vapor recompression with intermediate reboiler
Chemical Engineering Research and Design, 2018Co-Authors: Lianrui Gao, Xiaohong Yin, Xigang YuanAbstract:Abstract Conventional Vapor recompression assisted dividing wall column has limited energy-saving efficiency because of large temperature difference between two ends of column. Meanwhile, the side Vapor recompression assisted dividing wall column has limited heat integration because the side Vapor or liquid withdrawn flow rate is always small. To improve the energy performance of dividing wall column, this paper proposes the multistage Vapor recompression assisted dividing wall column with intermediate reboiler arrangements. In these arrangements, the Overhead Vapor is compressed by the first compressor, part of compressed Vapor is to Vaporize the side liquid in the intermediate reboiler, and the rest compressed Vapor is further compressed by the second compressor to be at higher temperature and Vaporize the bottom liquid in the bottom reboiler. Then heat integration can be performed between two VRC cycles under enough driving force of heat transfer. The simulation results in two separation cases show that the proposed configurations can largely improve the energy-saving performance of dividing wall column especially when the compression ratio of the first compressor is low and enough amount of liquid can be withdrawn from the side stage.
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New Intensified Heat Integration of Vapor Recompression Assisted Dividing Wall Column
Industrial & Engineering Chemistry Research, 2017Co-Authors: Xiaohong Yin, Xigang YuanAbstract:The energy efficiency of dividing wall column (DWC) can be improved by the Vapor recompression (VRC) technology, but large temperature difference between the Overhead and bottom of the DWC limits the application of VRC. To fully recover the heat generated by the VRC under large compression ratio, new intensified heat integrations of the VRC assisted DWC are provided in this paper. In the intensified configurations, the reboiler condensed liquid is used to Vaporize the side liquid stream in an intermediate reboiler (IR), the Overhead Vapor is preheated by the subcooled liquid. The best IR position can be gotten by the aid of the column grand composite curves (CGCC) of the DWC. Three separation cases with different ESI values are simulated to validity the energy capacity of the intensified configurations, the results show that the intensified heat integration technolgy can significantly improve the energy efficiency of the DWC with large temperature difference between the Overhead and the bottom.
