共查询到12条相似文献,搜索用时 15 毫秒
1.
Thermal coupling links to liquid‐only transfer streams: An enumeration method for new FTC dividing wall columns 下载免费PDF全文
Gautham Madenoor Ramapriya Mohit Tawarmalani Rakesh Agrawal 《American Institute of Chemical Engineers》2016,62(4):1200-1211
Novel dividing wall columns (DWCs) can be obtained by converting thermal couplings to liquid‐only transfer streams. Here, we develop a simple four‐step method to generate a complete set of DWCs containing n ? 2 dividing walls, for a given n‐component fully thermally coupled (FTC) distillation. Among the novel DWCs, some easy‐to‐operate DWCs possess the property that the vapor flow in every section of the DWC can be controlled during operation by means that are external to the column. We develop a simple method to enumerate all such easy‐to‐operate DWCs. We expect that the easy‐to‐operate DWCs can be operated close‐to‐optimality; leading to a successful industrial implementation of the n‐component (n ≥ 3) FTC distillation in the form of a DWC. As an illustration, we show figures of all easy‐to‐operate DWCs with two dividing walls for the four‐component FTC distillation. © 2015 American Institute of Chemical Engineers AIChE J, 62: 1200–1211, 2016 相似文献
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A systematic method to synthesize all dividing wall columns for n‐component separation—Part I 下载免费PDF全文
Gautham Madenoor Ramapriya Mohit Tawarmalani Rakesh Agrawal 《American Institute of Chemical Engineers》2018,64(2):649-659
We present an easy‐to‐use step‐wise procedure to synthesize an initial‐dividing wall column (i‐DWC) from any given n‐component basic distillation column sequence or its thermally coupled derivative. The procedure to be used is dependent on the nature of the distillation column sequence that is to be converted into a DWC, and comprises of an intuitive set of steps that we demonstrate through examples. It is noteworthy that, even for a ternary distillation, 15 potentially useful DWCs, some of which had been missing from the literature, have now been identified. This work significantly expands the search space of useful DWCs to separate any given multicomponent mixture. © 2017 American Institute of Chemical Engineers AIChE J, 64: 649–659, 2018 相似文献
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A systematic method to synthesize all dividing wall columns for n‐component separation: Part II 下载免费PDF全文
Gautham Madenoor Ramapriya Mohit Tawarmalani Rakesh Agrawal 《American Institute of Chemical Engineers》2018,64(2):660-672
We present a simple rule that, for the first time, enables exhaustive enumeration of dividing wall columns (DWCs) corresponding to any given thermally coupled distillation column‐configuration. With the successive application of our rule, every partition in a DWC can be extended all the way to the top and/or to the bottom of a column without losing thermodynamic equivalence to the original thermally coupled configuration. This leads to easy‐to‐operate DWCs with possible control/regulation of each and every vapor split by external means. As a result, we conclude that any given DWC can be transformed into a thermodynamically equivalent form that is easy‐to‐operate, and hence, there always exists at least one easy‐to‐operate DWC for any given thermally coupled distillation. Our method of enumerating and identifying easy‐to‐operate DWCs for an attractive thermally coupled configuration will contribute toward process intensification by providing ways to implement efficient and low‐cost multicomponent distillations. © 2017 American Institute of Chemical Engineers AIChE J, 64: 660–672, 2018 相似文献
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Xing Qian Kuan-Han Lin Shengkun Jia Lorenz T. Biegler Kejin Huang 《American Institute of Chemical Engineers》2023,69(6):e18062
Dividing wall columns (DWCs) are practical, effective, and promising among distillation process intensification technologies. Nonlinear model predictive control (NMPC) schemes are developed in this study to control the three-product DWCs. As these systems are intensely interactive and highly nonlinear, NMPC may be more suitable than the traditional PI control. The model is established based on Python and Pyomo platforms. As the original mathematical model of the column section is ill-posed, index reduction is used to avoid a high-index differential-algebraic equation (DAE) system. The well-posed index-1 system after index reduction is employed for the steady-state simulation and dynamic control in this study. Case studies with three DWC configurations to separate the mixture of ethanol (A), n-propanol (B), and n-butanol (C) show that the NMPC performs very well with small maximum deviations and short settling times. This demonstrates that the NMPC is a feasible and very effective scheme to control three-product DWCs. 相似文献
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热耦蒸馏及其选用原则 总被引:3,自引:0,他引:3
热耦蒸馏与常规蒸馏序列相比可减少能耗和设备投资,但其应用有一定的适用范围。文章通过严格模拟计算研究了热耦蒸馏适用范围,结果表明:该蒸馏技术主要适用于分离指数接近1的混合物,或分离指数小于1但中间组分含量较高的混合物。 相似文献
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通过将隔离壁精馏塔(DWC)的隔板两侧进行水平传热,可以进一步降低DWC的能量消耗。本文以假想的三组分混合物A,B,C为例,在三塔简捷计算初值的基础上,利用Mathematica对DWC进行最终的优化设计,并进行了主塔和副塔间水平传热的研究。结果表明,与未耦合的DWC对比,耦合DWC最大能够节能0.9%,且耦合塔板数与耦合面积能够影响DWC的节能效果。 相似文献
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Nguyen Van Duc Long Seunghyun LeeMoonyong Lee 《Chemical Engineering and Processing: Process Intensification》2010
The dividing wall column (DWC) has gained increasing application in a variety of chemical processes because of its potentiality in energy and capital cost savings in multicomponent separations. The main objective in this work is investigation of its use for removing the bottleneck phenomenon within the column when increasing the throughput of an existing distillation process, particularly, the acetic acid (AA) purification process. Optimal column sequence design, involving both conventional and DWC, is considered. The internal recycle flow distribution around the dividing wall was investigated as a primary optimizing variable. Several column arrangements were analyzed to show that the DWC requires less investment and energy costs than conventional distillation, the Petlyuk column, or the prefractionator arrangement. 相似文献
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对甲醇制烯烃粗产物的分离,设计一套基于隔壁精馏塔的分离新工艺。利用1个隔壁精馏塔,首先实现C-1、C2和C+3的清晰分割,然后经乙烯精馏塔、C3和C+4分离塔,丙烯精馏塔、C4和C+5分离塔,得到聚合级的乙烯和丙烯产品。利用Aspen plus软件对各精馏塔进行模拟和优化,得到各塔的塔参数和操作条件,进而对分离工艺进行全流程模拟。结果显示,乙烯和丙烯产品的质量分数分别达到99.99%和99.80%,满足聚合级的要求,说明本研究建立的基于隔壁精馏塔的甲醇制烯烃分离新工艺在技术上是可行的。 相似文献
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G. Prakash Narayan Mostafa H. Sharqawy Steven Lam Sarit K. Das John H. Lienhard V 《American Institute of Chemical Engineers》2013,59(5):1780-1790
Carrier gas based thermodynamic cycles are common in water desalination applications. These cycles often require condensation of water vapor out of the carrier gas stream. As the carrier gas is most likely a noncondensable gas present in very high concentrations (60–95%), a large additional resistance to heat transfer is present. It is proposed to reduce the aforementioned thermal resistance by condensing the vapor–gas mixture in a column of cold liquid rather than on a cold surface using a bubble column heat exchanger. A theoretical predictive model for estimating the heat‐transfer rates and new experimental data to validate this model are described. The model is purely physics based without the need for any adjustable parameters, and it is shown to predict heat rates within 0 to ?20% of the experimental values. The experiments demonstrate that heat‐transfer rates in the proposed device are up to an order magnitude higher than those achieved in existing state‐of‐the‐art dehumidifiers. © 2012 American Institute of Chemical Engineers AIChE J, 59: 1780–1790, 2013 相似文献
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High Nd3+→Yb3+ energy transfer efficiency in tungsten‐tellurite glass: A promising converter for solar cells 下载免费PDF全文
Francine Bettio Costa Keizo Yukimitu Luiz Antonio de Oliveira Nunes Marcio da Silva Figueiredo Junior Reis Silva Luis Humberto da Cunha Andrade Sandro Marcio Lima João Carlos Silos Moraes 《Journal of the American Ceramic Society》2017,100(5):1956-1962
This work reports on the energy transfer efficiency for Nd3+/Yb3+ co‐doped tellurite glasses (80TO2‐20WO3, in mol%,). The correlation between Yb3+ ion concentration and the downconversion mechanism was investigated using optical and thermal lens spectroscopies, which enabled investigation of the radiative and nonradiative processes, respectively, involved in energy transfer from neodymium to ytterbium. The Nd3+ near‐infrared fluorescence disappeared almost entirely when the maximum concentration of Yb3+ ions (4 mol%) was doped into the host. In contrast, there was a corresponding increase in the ytterbium emission at around 980 nm. When ytterbium was added, there was also a simultaneous reduction in the amount of heat generated by the sample due to a reduction in the nonradiative decay rate, corroborating the suspected high energy transfer efficiency of Nd3+→Yb3+. The results indicate that tungsten‐tellurite glasses may be of potential use in solar cells for matching the solar emission spectrum to the semiconductor cell. 相似文献