Design and control ofan ole!n metathesis reactive distillation column
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英语作文-揭秘集成电路设计中的设计规则与布局约束Integrated circuit (IC) design is a complex process that involves various design rules and layout constraints. In this article, we will delve into the secrets of IC design and explore the key considerations in designing and laying out integrated circuits.To begin with, one of the fundamental design rules in IC design is the minimum feature size. This refers to the smallest dimension that can be reliably manufactured on a chip. As technology advances, the minimum feature size decreases, allowing for more transistors to be packed onto a single chip. Designers must adhere to these rules to ensure the manufacturability and functionality of the IC.Another important design rule is the spacing between different components on the chip. This is known as the minimum spacing rule and ensures that there is sufficient isolation between adjacent components. Violating this rule can lead to interference and crosstalk, which can severely impact the performance of the IC. Designers must carefully consider the spacing requirements and optimize the layout to minimize any potential issues.Furthermore, the design of power distribution networks is crucial in IC design. Efficient power delivery is essential to ensure the proper functioning of the circuitry. Designers must consider factors such as voltage drop, current density, and thermal management when designing the power distribution network. By carefully analyzing and optimizing the power delivery system, designers can enhance the overall performance and reliability of the IC.In addition to design rules, layout constraints play a vital role in IC design. One such constraint is the placement of components on the chip. Proper component placement is essential to minimize signal delays and optimize the overall performance of the IC. Designers must consider factors such as signal integrity, power consumption, and thermal considerations when determining the optimal component placement.Another important layout constraint is the routing of interconnects. Interconnect routing refers to the process of connecting different components on the chip using metal traces. Designers must carefully plan and optimize the routing to minimize signal delays, reduce power consumption, and ensure proper signal integrity. Advanced routing algorithms and techniques are employed to achieve efficient and reliable interconnects.Moreover, the consideration of design for manufacturing (DFM) rules is crucial in IC design. DFM rules ensure that the design can be manufactured with high yield and reliability. Designers must consider factors such as lithography constraints, process variations, and mask alignment accuracy when designing the IC. By incorporating DFM rules into the design process, designers can minimize manufacturing issues and improve the overall yield of the IC.In conclusion, the design rules and layout constraints in integrated circuit design are essential for ensuring the manufacturability, functionality, and performance of the IC. Designers must carefully adhere to these rules and constraints while considering factors such as minimum feature size, component spacing, power distribution, component placement, interconnect routing, and design for manufacturing. By following these guidelines, designers can create efficient, reliable, and high-performance integrated circuits.。
你如何设计圣母院英语建议作文Notre-Dame Cathedral, an iconic symbol of French Gothic architecture, has stood as a testament to the nation's rich history and artistic prowess. However, the recent fire that partially destroyed this masterpiece of stone and glass has left the world in a state of shock and mourning. As the discussions turn to restoration and reconstruction, here are my suggestions on how to approach the task of rebuilding the Notre-Dame:1. Preservation of Historical Integrity: The restoration should prioritize maintaining the historical and architectural integrity of the cathedral. This means that while modern techniques and materials can be employed, the essence of the original design should be preserved.2. Incorporate Modern Safety Standards: While respecting the past, it's also crucial to bring the cathedral up to modern safety codes. This includes fire safety, structural stability, and accessibility for all visitors.3. Sustainability and Eco-Friendly Materials: The use of sustainable and eco-friendly materials should be considered. This not only aligns with current environmental concerns but also ensures the longevity of the structure.4. Public Input and International Collaboration: Engage the public in the restoration process. An internationaldesign competition could be held to invite innovative ideas from architects and designers worldwide.5. Documentation and Transparency: Ensure that the entire process is well-documented and transparent. This will not only serve as a historical record but also allow for public oversight and trust in the project.6. Cultural and Artistic Inclusion: The restoration could be an opportunity to include contemporary artistic elements that reflect the diversity and cultural evolution of France today.7. Fundraising and Financial Oversight: Given the significant costs involved, a transparent and accountable fundraising campaign should be launched. Financial oversight will be crucial to ensure that funds are used efficiently and for their intended purpose.8. Educational Programs: Develop educational programs and materials that explain the history, architecture, andcultural significance of Notre-Dame to both the public and students.9. Community Involvement: Involve local communities and craftsmen in the restoration process. This not only provides employment but also helps to pass on traditional skills and knowledge.10. Long-Term Maintenance Plan: Create a comprehensive maintenance plan that ensures the ongoing preservation of thecathedral once it is restored.The restoration of Notre-Dame Cathedral is not just a task for architects and engineers; it is a collective effort that requires the input and support of the global community. By approaching the restoration with care, respect for the past, and an eye towards the future, we can ensure that Notre-Dame continues to inspire awe and reverence for generations to come.。
这个设计真特别作文英语The Unique Design。
The design of this particular object is truly one of a kind. It stands out from the rest due to its innovative and creative features. The unique design of this object has caught the attention of many, and it has become a topic of conversation among those who have seen it. In this essay, I will discuss the special qualities of this design and whyit is so remarkable.First and foremost, the unique design of this object is evident in its shape and structure. Unlike traditional objects of its kind, it has a distinct and unconventional form that sets it apart. The designer has taken a bold approach in creating something that challenges the norms and expectations of design. The result is a visually striking and captivating object that commands attention.Furthermore, the materials used in the construction ofthis object are also a key factor in its unique design. The designer has opted for unconventional and unexpected materials, which contribute to the overall aesthetic and functionality of the object. This bold choice of materials adds an element of surprise and delight to the design, making it all the more special and memorable.In addition to its shape and materials, thefunctionality of this object is also a testament to its unique design. It serves a purpose that is not only practical but also innovative. The designer has thought outside the box and created something that fulfills a need in a way that is fresh and original. This aspect of the design has garnered much praise and admiration from those who have experienced its functionality firsthand.Moreover, the attention to detail in the design of this object is truly remarkable. Every aspect of its construction has been carefully considered and executed with precision. From the smallest components to the overall aesthetic, the designer has paid meticulous attention to every detail, resulting in a design that is cohesive andharmonious in every aspect.Finally, the impact that this unique design has had on its audience cannot be overlooked. It has sparked conversations and inspired others to think differently about design. Its influence has extended beyond the realm of its intended use, serving as a source of inspiration for those who appreciate creativity and originality in design.In conclusion, the unique design of this object is a testament to the power of creativity and innovation. Its unconventional shape, materials, functionality, attention to detail, and impact on its audience all contribute to its exceptional and remarkable design. It has set a new standard for what is possible in design, and its influence will undoubtedly be felt for years to come. This design is truly one of a kind, and it will continue to be celebrated and admired for its special qualities.。
英文回答:In my daily life, I often encounter many examples ofpliance with 21 design principles。
In the kitchens of the home, the temperature control buttons in the oven are designed to be intuitive and easy to operate, consistent with the visualization and feedback in the design principles。
When the temperature of the oven needs to be regulated, changes in temperature can be seen intuitively only through a rotating button, while the sound alarm operation of the thorium is heard to be effective。
This design not only facilitates the operation of cooking, but also ensures accurate and reliable temperature control。
This concept of design permeates our daily lives and is a tangible manifestation of the service that our party actively advocates for, and the advancement of science and technology。
在我日常生活中,经常会遇到许多符合21条设计原则的例子。
英语作文-掌握集成电路设计中的关键技术与方法Integrated Circuit (IC) design plays a pivotal role in modern electronics, serving as the foundation for virtually all electronic devices we use today. Mastering the key techniques and methods in IC design is crucial for engineers and researchers in this field. This article explores the essential aspects of IC design, highlighting the methodologies and technologies that drive innovation and efficiency in this complex discipline.### Understanding IC Design Fundamentals。
At its core, IC design involves the creation of miniature electronic circuits that integrate thousands to billions of components onto a single semiconductor chip. This integration enables devices to perform complex functions while minimizing size and power consumption. The process begins with conceptualizing the circuit's functionality and architecture, followed by detailed design and verification stages.### Key Stages in IC Design。
ieee conference on decision and control 检索IEEE Conference on Decision and Control is an annual conference that focuses on theory and applications of control systems and decision-making processes. The conference is considered to be one of the leading events in the field of control systems and attracts researchers and practitioners from all over the world. This paper will provide an overview of the conference and present some of the key topics that have been discussed in the conference over the years.The Conference on Decision and Control aims to provide a platform for researchers and practitioners to present and discuss their latest findings and innovations in control systems and decision-making processes. The conference covers a wide range of topics, including:- Control theory and applications- Optimization and optimal control- Estimation and identification- Robotics and automation- Cyber-physical systems and networks- Automotive and aerospace systems- Power systems and renewable energy- Biomedical systems and healthcare- Manufacturing and industrial systems- Signal processing and communication systemsThe conference also features workshops, tutorials, and special sessions that provide more focused discussions and training on specific topics. In recent years, some of the hot topics that havebeen discussed in the conference include:- Reinforcement learning and deep learning for control- Data-driven approaches for control and decision-making- Multi-agent systems and game theory- Cybersecurity and privacy in control systems- Control of autonomous systems- Control of flexible and distributed systemsThe Conference on Decision and Control has a long history of academic excellence and has attracted some of the top researchers in the field. Over the years, the conference has published numerous high-quality papers that have contributed significantly to the field of control systems. Some of the notable papers that have been published in the conference include:- "Modeling and Control of Complex Systems" by John Doyle et al. (1998)- "Stochastic Optimal Control and the U.S. Defense Suppression Problem" by Michael Athans and Peter Falb (1968)- "State-Space Representation and Optimal Control of Complex Systems" by Richard Bellman (1961)In addition to publishing high-quality research papers, the Conference on Decision and Control has also been instrumental in promoting collaborations and networking among researchers and practitioners in the field. The conference provides a unique opportunity for researchers and practitioners from different disciplines to interact and exchange ideas, leading to new research collaborations and partnerships.In conclusion, the IEEE Conference on Decision and Control is a premier event in the field of control systems and decision-making processes. The conference brings together leading researchers and practitioners from all over the world to discuss the latest advancements and innovations in the field. With its wide-ranging topics, high-quality research publications, and networking opportunities, the conference has played a significant role in advancing the field of control systems and decision-making processes.。
摘要机械手是在自动化生产过程中使用的一种具有抓取和移动工件功能的自动化装置,由其控制系统执行预定的程序实现对工件的定位夹持。
完全取代了人力,节省了劳动资源,提高了生产效率。
本设计以实现铣床自动上下料为目的,设计了个水平伸缩距为200mm,垂直伸缩距为200mm具有三个自由度的铣床上下料机械手。
机械手三个自由度分别是机身的旋转,手臂的升降,以及机身的升降。
在设计过程中,确定了铣床上下料机械手的总体方案,并对铣床上下料机械手的总体结构进行了设计,对一些部件进行了参数确定以及对主要的零部件进行了计算和校核。
以单片机为控制手段,设计了机械手的自动控制系统,实现了对铣床上下料机械手的准确控制。
关键词:机械手;三自由度;上下料;单片机AbstractManipulator , an automation equipment with function of grabbing and moving the workpiece ,is used in an automated production process.It perform scheduled program by the control system to realize the function of the positioning of the workpiece clamping. It completely replace the human, saving labor resources, and improve production efficiency.This design is to achieve milling automatic loading and unloading .Design a manipulator with three degrees of freedom and 200mm horizontal stretching distance, 120mm vertical telescopic distance. Three degrees of freedom of the manipulator is body rotation, arm movements, as well as the movements of the body. In the design process, determine the overall scheme of the milling machine loading and unloading manipulator and milling machine loading and unloading manipulator, the overall structure of the design parameters of some components as well as the main components of the calculation and verification. In the means of Single-chip microcomputer for controlling, design the automatic control system of the manipulator and achieve accurate control of the milling machine loading and unloading.Key words: Manipulator; Three Degrees of Freedom; Loading and unloading; single chip microcomputer目录摘要.........................................................................I第1章绪论.............................................................11.1选题背景................................................... (1)1.2设计目的.........................................................11.3国内外研究现状和趋势............................................21.4设计原则.........................................................2第2章设计方案的论证..................................................32.1 机械手的总体设计...............................................32.1.1机械手总体结构的类型....................................32.1.2 设计具体采用方案........................................42.2 机械手腰座结构设计.............................................52.2.1 机械手腰座结构设计要求.................................52.2.2 具体设计采用方案........................................52.3 机械手手臂的结构设计...........................................62.3.1机械手手臂的设计要求....................................62.3.2 设计具体采用方案........................................72.4 设计机械手手部连接方式.........................................72.5 机械手末端执行器(手部)的结构设计...........................82.5.1 机械手末端执行器的设计要求.............................82.5.2 机械手夹持器的运动和驱动方式..........................92.5.3 机械手夹持器的典型结构.................................92.6 机械手的机械传动机构的设计..................................102.6.1 工业机械手传动机构设计应注意的问题...................102.6.2 工业机械手传动机构常用的机构形式.....................102.6.3 设计具体采用方案.......................................122.7 机械手驱动系统的设计.........................................122.7.1 机械手各类驱动系统的特点..............................122.7.2 机械手液压驱动系统.....................................132.7.3机身摆动驱动元件的选取................................132.7.4 设计具体采用方案.......................................142.8 机械手手臂的平衡机构设计.....................................14第3章理论分析和设计计算............................................163.1 液压传动系统设计计算..........................................163.1.1 确定液压传动系统基本方案...............................163.1.2 拟定液压执行元件运动控制回路...........................173.1.3 液压源系统的设计........................................173.1.4 确定液压系统的主要参数.................................173.1.5 计算和选择液压元件......................................243.1.6机械手爪各结构尺寸的计算...................................26 第4章机械手控制系统的设计..........................................284.1 系统总体方案..................................................284.2 各芯片工作原理................................................284.2.1 串口转换芯片............................................284.2.2 单片机...................................................294.2.3 8279芯片...............................................304.2.4 译码器...................................................314.2.5 放大芯片................................................324.3 电路设计..................................................334.3.1 显示电路设计............................................334.3.2 键盘电路设计............................................334.4 复位电路设计..................................................334.5 晶体振荡电路设计.............................................344.6 传感器的选择..................................................34结论.....................................................................36致谢.....................................................................37参考文献................................................................38CONTENTS Abstract (I)Chapter 1 Introduction (1)1.1 background (1)1.2 design purpose (1)1.3 domestic and foreign research present situation and trends (2)1.4 design principles (2)Chapter 2 Design of the demonstration (3)2.1manipulator overall design (3)2.1.1 manipulator overall structure type (3)2.1.2 design adopts the scheme (4)2.2 lumbar base structure design of mechanical hand (5)2.2.1 manipulator lumbar base structure design requirements (5)2.2.2specific design schemes (5)2.3mechanical arm structure design (6)2.3.1 manipulator arm design requirements (6)2.3.2 design adopts the scheme (7)2.4 design of mechanical hand connection mode (7)2.5 the manipulator end-effector structure design (8)2.5.1 manipulator end-effector design requirements (8)2.5.2 manipulator gripper motion and driving method (9)2.5.3 manipulator gripper structure (9)2.6 robot mechanical transmission design (10)2.6.1 industry for transmission mechanism of manipulator design shouldpay attention question (10)2.6.2 industrial machinery hand transmission mechanism commonlyused form of institution (10)2.6.3 design adopts the scheme (12)2.7 mechanical arm drive system design (12)2.7.1 manipulator of various characteristics of the drive system (12)2.7.2 hydraulic drive system for a manipulator (13)2.7.3 Body swing the selection of drive components (13)2.7.4 Design the specific use of the program (14)2.8 mechanical arm balance mechanism design (14)Chapter 3 Theoretical analysis and design calculation (16)3.1 hydraulic system design and calculation (16)3.1.1 the basic scheme of hydrauic transmission system (16)3.1.2 formulation of the hydraulic actuator control circuit (17)3.1.3 hydraulic source system design (17)3.1.4 determine the main parameters of the hydraulic system (17)3.1.5 calculation and selection of hydraulic components (24)3.1.6 Manipulator calculation of the structural dimensions (26)Chapter 4 The robot control system design (28)4.1 Overall scheme (28)4.2 Chip works (28)4.2.1 serial conversion chip (28)4.2.2 MCU (29)4.2.3 8279 chip (30)4.2 .4 decoder (31)4.2.5 amplifier chip (32)4.3 Circuit design (33)4.3.1 show the circuit design (33)4.3.2 The keyboard circuit design (33)4.4 Reset circuit design (33)4.5 crystal oscillation circuit design (34)4.6 sensor selection (34)Conclusion (36)Acknowledgements (37)References (38)第1章绪论1.1选题背景机械手是在自动化生产过程中使用的一种具有抓取和移动工件功能的自动化装置,它是在机械化、自动化生产过程中发展起来的一种新型装置。
The Science of Spacesuit DesignSpacesuits are crucial pieces of technology that enable astronauts to survive and thrive in the harsh environment of space. The science behind spacesuit design is a fascinating and complex field that involves a combination of engineering, materials science, and human physiology.One of the key factors in spacesuit design is the need to provide a pressurized and oxygenated environment for astronauts to breathe and operate in. This requires the spacesuit to be carefully sealed to prevent leaks and to be constructed from materials that can withstand the extreme temperature changes and radiation levels of space. Additionally, the spacesuit must be able to protect astronauts from micrometeoroids and other debris that could pose a threat to their safety.Another important consideration in spacesuit design is mobility. Astronauts need to be able to move freely and easily while wearing their spacesuits in order to perform tasks such as conducting experiments, repairing equipment, and exploring the surface of other planets. Designing a spacesuit that allows for this level of mobility while still providing the necessary protection and life support is a significant challenge for engineers.In addition to these practical considerations, spacesuit design also takes into account the psychological and physiological needs of astronauts. Spending long periods of time in a spacesuit can be physically and mentally demanding, so designers must ensure that the suit is comfortable, ergonomic, and conducive to the overall well-being of the wearer. Factors such as temperature regulation, moisture control, and waste management are all important aspects of spacesuit design that must be carefully considered.One of the latest advancements in spacesuit design is the development of so-called "smart" spacesuits that incorporate technology such as sensors, cameras, and communication systems to enhance the capabilities of astronauts while in space. These smart spacesuits can help astronauts monitor their vital signs, navigate their surroundings, and stay in communication with mission control on Earth, making them even more effective and efficient in their work.Overall, the science of spacesuit design is a multifaceted and dynamic field that continues to evolve as technology advances and our understanding of space exploration grows. By combining expertise in engineering, materials science, and human factors, designers are able to create spacesuits that are not only functional and practical, but also comfortable, safe, and supportive of the physical and mental well-being of astronauts. As we look to the future of space exploration, spacesuit design will continue to play a crucial role in enabling humans to venture further into the cosmos and expand our knowledge of the universe.。
有关设计和创新的英语作文Design and Innovation。
Design and innovation are two crucial elements intoday's fast-paced and competitive world. They play a significant role in driving progress, improving efficiency, and enhancing the quality of life. In this essay, we will explore the importance of design and innovation, their impact on various aspects of our lives, and the ways in which they can be fostered and encouraged.First and foremost, design is the process of creating solutions to problems or challenges. It involves a deep understanding of the needs and preferences of the end-users, as well as the ability to think creatively and critically. Good design not only satisfies functional requirements but also delights and engages users. From the sleek andintuitive interface of a smartphone to the ergonomic and stylish furniture in our homes, design surrounds us and influences our daily experiences.Innovation, on the other hand, is the process of introducing new ideas, products, or methods that bring about positive change. It is the driving force behind progress and growth in all fields, from technology and science to business and social development. Innovation can take many forms, such as the invention of a new product, the improvement of an existing process, or the introduction of a groundbreaking idea.The relationship between design and innovation is symbiotic. Design often serves as the catalyst for innovation, providing the creative spark and the practical framework for new ideas. Conversely, innovation challenges designers to push the boundaries of what is possible and to explore new ways of addressing problems. Together, design and innovation drive each other forward, leading to the creation of products, services, and experiences that are both functional and transformative.The impact of design and innovation can be seen in all aspects of our lives. In the business world, companies thatinvest in design and innovation are more likely to succeed and stay ahead of the competition. By creating productsthat are not only useful but also aesthetically pleasingand user-friendly, these companies can attract and retain customers, build brand loyalty, and drive sales. In addition, innovative business models and processes can lead to increased efficiency, reduced costs, and higher profitability.In the field of technology, design and innovation have revolutionized the way we communicate, work, and entertain ourselves. The sleek and intuitive interfaces of smartphones and tablets have made it easier than ever to access information and connect with others. Meanwhile, innovative technologies such as artificial intelligence, virtual reality, and 3D printing are opening up new possibilities in fields as diverse as healthcare, education, and entertainment.In the realm of social development, design and innovation have the power to address pressing global challenges, such as poverty, inequality, and environmentalsustainability. By creating products and services that are affordable, accessible, and environmentally friendly, designers and innovators can make a positive impact on the lives of people around the world. For example, the design of low-cost, off-grid solar lamps has brought light and electricity to millions of people in developing countries, improving their quality of life and reducing their reliance on fossil fuels.To foster and encourage design and innovation, it is essential to create an environment that supports and rewards creativity, risk-taking, and collaboration. This can be achieved through education, research, and public policy. In schools and universities, students should be encouraged to think critically, experiment with new ideas, and work across disciplines. Research institutions and companies should invest in R&D, provide resources and support for innovative projects, and create a culture that values and celebrates creativity. At the same time, governments can play a role by providing funding, incentives, and infrastructure for design and innovation, as well as by promoting policies that encouragesustainability and social responsibility.In conclusion, design and innovation are essential drivers of progress and growth in today's world. They have a profound impact on business, technology, and social development, and they have the potential to address some of the most pressing challenges facing humanity. By fostering an environment that supports and encourages creativity and collaboration, we can unleash the full potential of design and innovation and create a better future for all.。
Applied Control Theory and Design Control theory and design are crucial components of engineering and technology, playing a significant role in ensuring the stability and performance of various systems. From simple household appliances to complex industrial processes, control theory and design are applied to regulate and manage the behavior of dynamic systems. This response aims to explore the importance of control theory and design from multiple perspectives, including their impact on technological advancements, industrial applications, and everyday life. From a technological standpoint, control theory and design are essential for the development and operation of advanced systems such as autonomous vehicles, robotics, and aerospace technologies. These systems rely on sophisticated control algorithms to maintain stability, navigate through complex environments, and perform precise tasks. Withouteffective control theory and design, these technologies would be prone to instability, error, and inefficiency, posing significant risks to both the system itself and its surroundings. In the industrial sector, control theory and design are instrumental in optimizing production processes, enhancing efficiency, and ensuring product quality. Industrial control systems are used to regulatevariables such as temperature, pressure, flow rate, and chemical composition in various manufacturing processes. By implementing advanced control strategies, industries can minimize waste, reduce energy consumption, and improve overall productivity, leading to cost savings and environmental benefits. Moreover,control theory and design have a profound impact on everyday life, influencing the performance of consumer electronics, transportation systems, and environmental control systems. For instance, the cruise control system in automobiles utilizes control theory to maintain a constant speed, improving fuel efficiency and driver comfort. Heating, ventilation, and air conditioning (HVAC) systems in buildingsrely on control algorithms to regulate indoor climate conditions, ensuring occupant comfort and energy conservation. From a theoretical perspective, control theory provides a framework for analyzing the behavior of dynamic systems and designing control strategies to achieve desired performance objectives. It encompasses various concepts such as stability, controllability, observability,and robustness, which are fundamental to the understanding and synthesis ofcontrol systems. By studying control theory, engineers gain insights into the principles of feedback and feedforward control, as well as the mathematical tools for modeling and analyzing dynamic systems. In practical applications, control design involves the selection of appropriate control algorithms, the tuning of controller parameters, and the implementation of hardware or software components to realize the desired control objectives. This process often requires a multidisciplinary approach, integrating knowledge from fields such as mathematics, physics, computer science, and electrical engineering. Furthermore, the design of control systems must consider practical constraints such as system dynamics, actuator and sensor limitations, and external disturbances. In conclusion,control theory and design play a critical role in shaping the technological landscape, driving advancements in engineering, and enhancing the performance of various systems. Their impact extends beyond the realm of engineering, influencing industrial processes, consumer products, and everyday experiences. As technology continues to evolve, the principles of control theory and design will remain essential for ensuring the stability, efficiency, and reliability of dynamic systems.。
Chemical Engineering Science57(2002)715–733/locate/cesDesign and control ofan oleÿn metathesis reactivedistillation columnMuhammad A.Al-Arfaj,William L.Luyben∗Department of Chemical Engineering,Lehigh University,Iacocca Hall,111Research Drive,Bethlehem,PA18015-4791,USAReceived29May2001;accepted19October2001AbstractThis paper considers the design and control ofa reactive distillation column in which one reactant is consumed and two products are formed(A B+C).The volatilities are B¿ A¿ C,i.e.the reactant is intermediate boiling between the two products.The metathesis of2-pentene is considered as the demonstrative example.The column has a single f eed ofthe intermediate boiling reactant.The distillate contains mostly light component and the bottoms mostly heavy.Three designs are considered:the base case(low-conversion=low-pressure),a low-conversion=high-pressure case and a high-conversion= high-pressure case.The base design is obtained from the literature,and the other two steady-state designs are optimized with respect to the total annual cost.All the designs are found to be openloop stable.Five control structures are studied for the base design.Then the best two structures are applied to the remaining two designs.This category ofreactive distillation exhibits less challenging problems than other categories since it uses a single feed,which eliminates the need for the control structure to perfectly balance two fresh feeds. Simulation results demonstrate that e ective dynamic control is provided by a control structure that uses two temperatures to maintain the purities ofboth product streams.No internal composition measurement is required.This structure is f ound to be robust and stable and rejects loads and tracks setpoints very well.?2002Elsevier Science Ltd.All rights reserved.Keywords:Reactive distillation;Process design and control;Oleÿn metathesis1.IntroductionReactive distillation is sometimes an excellent alterna-tive to conventional owsheets with separate reaction and separation sections.It is particularly e ective for reversible reactions with low equilibrium constants.Ofcourse the re-actant and product volatilities must be such that products can be removed and reactants retained inside the column.The temperature levels for both reaction and vapor–liquid equi-librium must overlap.Signiÿcant reductions in both capital and energy costs are possible in some systems.The literature in reactive distillation has grown rapidly in recent years and is summarized in the new book by Do-herty and Malone(2001).Steady-state design is considered in many papers.Openloop dynamics and multiple steady states are discussed in several others.However,there have∗Corresponding author.Tel.:+1-610-758-4256;fax:+1-610-758-5297.E-mail address:wll0@(W.L.Luyben).been relatively few papers that discuss closedloop control of reactive distillation columns.These are reviewed in a recent publication(Al-Arfaj&Luyben,2000).We have studied control structures for two generic types ofreactive distillation columns in previous papers(A l-A rf aj &Luyben,2000;Luyben,2000;Al-Arfaj&Luyben in press, submitted for publication).1.A hypothetical ideal system and the methyl acetate sys-tem with two reactants and two products:A+B C+D.2.The ETBE system with two reactants and a single prod-uct:A+B C.In this paper,we extend these studies to consider another generic class ofreactive distillation in which there is a single reactant and two products:A B+C.The speciÿc chemical system considered is oleÿn metathesis,whose steady-state design has been studied by Okasinski and Doherty(1998). The reactant is intermediate boiling between the light and heavy products.As our study illustrates,this reactive distil-lation system is much more easily controlled than any ofthe systems previously studied.The control structure is relieved0009-2509/02/$-see front matter?2002Elsevier Science Ltd.All rights reserved. PII:S0009-2509(01)00442-0716M.A.Al-Arfaj,W.L.Luyben/Chemical Engineering Science57(2002)715–733ofthe need to provide a way to perf ectly balance the two reactants fed to the column so that reaction stoichiometry is satisÿed.2.Process descriptionOleÿn metathesis is used in the petrochemical industry.In this paper,we consider the metathesis of2-pentene to f orm the two products2-butene and3-hexene.2C5H10 C4H8+C6H12:This reaction is a good candidate for reactive distillation for several reasons:1.The reaction takes place in the liquid phase at temper-atures that are suitable for vapor–liquid equilibrium re-quirements ofdistillation.2.All the components are hydrocarbons and similar in chemical structure.Deviations from ideality are negligi-ble,and no azeotropes are formed.3.The normal boiling points ofthe components allow an easy separation between the reactant2-pentene(310K) and the two products(light distillate product2-butene at 277K and heavy bottoms product3-hexene at340K). The reaction is kinetically controlled.Detailed physi-cal properties and kinetic data are provided by Okasinski and Doherty(1998)and Chen,Huss,Malone,and Do-herty(2000).We use this information as the basis of our steady-state and dynamic models.The model assumptions are:1.Ideal gas and Raoult’s law are valid.2.Power-law kinetics.3.No heat ofreaction.4.Constant molar over ow.5.Constant molar holdup distribution.6.Partial reboiler and a total condenser(no reaction takes place in either ofthem).3.Steady-state designsThree di erent design cases are considered in this paper. Theÿrst is that studied by Okasinski and Doherty(1998), which has a low conversion(93%)and operates at atmo-spheric pressure.The second has the same conversion but the pressure is increased so that cooling water can be used in the condenser.The third case is a high conversion design. Similar control structures are studied for all the three cases.3.1.Base case(low-conversion=low-pressure) Okasinski and Doherty(1998)proposed a design method for kinetically controlled reactive distillation.They applied their method to the metathesis of2-pentene.They provide a review ofthis process as well as all the chemical and physical data.Chen et al.(2000)use this case as an example in their work in which they show the steady-state e ect of tray holdup and re ux ratio on conversion.The base design,which is taken from Okasinski and Do-herty(1998),is summarized in Table1.The temperature and composition proÿles are shown in Fig.1.In this design, the product purities are93:4mol%.The column diameter is around2m,and the stage holdup is6:1kmol,which is equivalent to an acceptable tray height of20cm.Pressure is1atm.The column has12reactive trays and is fed in the middle.3.2.Steady-state design2(low-conversion=high-pressure) The base-case design at1atm pressure gives a re ux-drum temperature of280K.This is too low to permit the use ofcooling water in the condenser,so ref rigeration would have to be used.This means very expensive heat removal. Ifthere is no high-temperature limitation,the operating pressure could be increased so that cooling water can be used.The exothermic reaction has a low heat ofreaction (about−25kJ=kmol),so the equilibrium constant does not decrease signiÿcantly as temperature is increased.In this second design,the operating pressure is set at5atm,giv-ing a re ux-drum temperature of329K(the bubblepoint temperature ofthe C=4distillate).3.2.1.E ect of design parametersTo obtain a better understanding ofthe process,the e ects ofvarious design parameters on the steady-state design are explored.The number oftrays,the operating pressure,the holdup per tray and the re ux ratio are studied.In all cases the fresh feed is located in the middle of the column.This is justiÿed by the fact that the average relative volatility between the reactant and each ofthe two products is about the same( =2:5for C4=C5and2.3for C5=C6).Ifthe degree ofseparation di culty were greater f or one ofthe separations,the number oftrays in the corresponding section would be relatively larger in that section than in the other. Fig.2A shows the e ect ofpressure on conversion f or di erent numbers oftrays.Re ux ratio isÿxed at4,and tray holdup is constant at6:1kmol.The conversion drops after reaching an optimum pressure when only a small number of trays are used.This is due to the adverse impact ofpressure on the relative volatilities in this hydrocarbon system.How-ever,this does not happen when there are a large number oftrays because separation capacity is not limiting perf or-mance.These results indicate that high conversions cannot be achieved in a12-tray column,even ifit is operated at the optimum pressure ofabout2:5atm.Additional trays are required.Fig.2B shows that higher conversion can alternatively be obtained when larger tray liquid holdups are used.How-ever,there are hydraulic constraints on how much liquid can be used on each tray because excessive liquid heightsM.A.Al-Arfaj,W.L.Luyben /Chemical Engineering Science 57(2002)715–733717Table 1Details design variables ∗Low conversion =Low conversion =High conversion =low pressure (base)high pressure high pressure Pressure (atm)155Conversion (%)93.493.499.0Total trays 122838Feed tray 71520Re ux ratio4 1.7 1.84Vapor boilup (kmol =h)250135142Diameter (m)211Holdup (kmol =tray) 6.1 1.5 1.5Distillate comp.C =40.93420.93350.9901(mole fraction)C =50.06550.06570.0099C =60.00030.00080.0000Bottoms comp.C =40.00020.00060.0000(mole fraction)C =50.06570.06620.0099C =60.93410.93320.9901Temperature (K)T 1333.5395.7400.8T N F 308.2361.1361.3T N T281.1332.5328.3TAC (MM $=year)1.43140.30740.3387∗Allcases are fed the same feed (100kmol =h C =5)and have the same product owrates (distillate =50kmol =h and bottoms =50kmol =h).Tray numbering is from the bottom up.produce large pressure drops.Conversion decreases with increasing pressure due to the limited separation capacity.Fig.2C shows that as the re ux ratio increases the conver-sion increases and the separation becomes easier.This sug-gests that higher re ux ratios could be used to o set the small number oftrays,but the energy cost would probably make this alternative uneconomical.3.2.2.Optimum economic steady-state designIn order to come up with a more realistic design,an opti-mization with respect to the number oftrays and re ux ratio is performed.The objective function is minimum total an-nual cost (TA C)ofboth energy and capital.The optimum column has more trays than the base case and requires less heat input.Running at a pressure of5atm means that va-por density is higher,so vapor velocities are lower.Both these result in a smaller diameter column ofabout 1m at the optimum.Since the diameter is decreased by a factor of two from the base-case design,the holdup is reduced by a factor of four for the same tray liquid height.A reasonable liquid height of20cm is used in order to maintain a reason-able pressure drop through the tray.Therefore,the holdup is 1:5kmol =tray.The feed tray is always in the middle of the column.For a given total number oftrays,the re ux ratio is varied to achieve the same conversion as the base case (93.4%).Fig.3A shows that the optimum number oftrays is about 28.The re ux ratio for this column is 1.7,and the operating pressure is 5atm.Fig.3B shows that the optimum numberoftrays f or a high-conversion case (99%)considered in the next section has increased to about 38with,ofcourse,a higher total annual cost.Figs.3A and B show that the TA C is not very sensitive to the total number oftrays.For example,changing the total number oftrays in the optimum high-conversion design by ±2(±5%)results in an increase in the TAC by only 0.13%.More details ofthe low-conversion =high-pressure design are given in Table 1.Fig.4gives temperature and compo-sition proÿles throughout the column.Note the signiÿcant temperature changes in both the stripping and rectifying sec-tions as the product purities change.This indicates that it may be possible to use temperatures to maintain product purities at both ends ofthe column.The control studies dis-cussed later conÿrm this expectation.3.3.Steady-state design 3(high-conversion =high-pressure)To explore the e ect ofconversion on both the steady-state design and the dynamic control,a 99%con-version case is studied.The optimization yields the design given in Table 1(last column).The optimum column has 38reactive trays,re ux ratio of1.84,holdup of1:5kmol =tray and operating pressure of5atm.Temperature and compo-sition proÿles are shown in Fig.5.Table 1shows that the higher conversion case has more trays (38versus 28)and a slightly higher re ux ratio (1.84718M.A.Al-Arfaj,W.L.Luyben /Chemical Engineering Science 57(2002)715–733270280290300310320330340R123456789101112CNT (K)0.10.20.30.40.50.60.70.80.91R 123456789101112CNL i q u i d M o l e F r a c t i o nposition &temperature proÿle (design 1).versus 1.7).It is interesting to compare the cost ofthese de-signs.The base design is the most expensive design since it uses high re ux (high energy)and refrigeration in the con-denser,which is very expensive ($20=GJ for 5◦C).The other two designs are reasonably close to each other.Another com-parison is to look at the cost per unit ofproduct.Since all the designs use the same amount of fresh feed,the raw material cost is ÿxed.Therefore,to calculate the cost per unit of prod-uct we divide the TAC by the annual production rate.For example,for the base design,it is 1,431,430[$=y]=(0:934∗50[kmol =h])=8160[h =y]=3:76[$=kmol].The cost per unit ofproduct f or the low-conversion =high-pressure design is 0:81[$=kmol]and for the high-conversion =high-pressure de-sign is 0:84[$=kmol].From this,one can suggest that the low-conversion =high-pressure design is more economical;however,since the product purity is not high,a recovery system may be needed that would increase the overall cost.The high-conversion =high-pressure design should not re-quire any further processing.4.Control studiesFour control structures are studied for the base-case de-sign,as shown in Figs.6and 7.All the structures are SISO structures with PI controllers (P only on levels).M.A.Al-Arfaj,W.L.Luyben /Chemical Engineering Science 57(2002)715–73371993949596979899100123456Pressure (atm)C o n v e r s i o n (%)(A)(B)(C)93949596979899100123456Pressure (atm)C o n v e r s i o n (%)93949596979899123456Pressure (atm)C o n v e r s i o n (%)Fig.2.(A )E ect ofchanging N T ,RR =4,holdup =6:1kmol =tray,D =50kmol =h;(B)e ect ofchanging tray holdup,RR =4,N T =12kmol =tray,D =50kmol =h and (C)e ect ofchanging re ux ratio,N T =12,holdup =6:1kmol =tray,D =50kmol =h.720M.A.Al-Arfaj,W.L.Luyben /Chemical Engineering Science 57(2002)715–7332426283032NT A C ($/y e a r)3436384042NT A C ($/y e a r )(A)(B)Fig.3.(A)Optimum TAC (Design 2—93.4%conversion)and (B)optimum TAC (Design 3—99.0%conversion).The controllers are tuned using the Tyreus–Luyben tun-ing method (Tyreus &Luyben,1992).The relay-feedback method (Yu,1999)is used to obtain the ultimate gain and ultimate period.Valves are designed to be halfopen at steady state.Two measurement lags of30s each are used in all composition or temperature loops.Similar labeling of control structures is used in this paper so that comparison with previous work can be easily made.Only the two most promising control structures are tested for the other two designs.This system uses ideal chemical and physical models.It is expected that this process will be openloop stable and exhibits less nonlinearity compared to other systems that feature complex relationships (e.g.methyl acetate reactive distillation).To examine the dynamic stabil-ity ofthe openloop system,a large 100%pulse in f eed rate is made.This huge pulse signal is used in orderto excite any nonlinearity that might be present in the system.The re ux ow and the vapor boilup are held constant.The re ux drum level is controlled by the dis-tillate owrate,and the base level is controlled by the bottoms owrate.Simulation results for all three design cases show that the system returns to its nominal condi-tions.These results indicate that the system is openloop stable.The control structures studied use either dual composition control,single-end composition control,dual temperature control or single-end temperature control.4.1.CS1(dual composition)This is the basic structure where the purities ofthe two products are both controlled by direct composition con-M.A.Al-Arfaj,W.L.Luyben /Chemical Engineering Science 57(2002)715–733721320330340350360370380390400R 12345678910111213141516171819202122232425262728CNT (K)0.00.10.20.30.40.50.60.70.80.91.0R12345678910111213141516171819202122232425262728CNL i q u i d M o l e F r a c t i o nposition and temperature proÿle (Design 2).trollers.The re ux owrate is manipulated to control the butene purity in the distillate.The hexene purity in the bottoms is controlled by manipulating the vapor boilup (Fig.6A ).A slight variation ofthis structure was also studied in which the C5impurities in the products were controlled instead ofthe product purities.There was little di erence in performance.4.2.CS1-RR (single-end composition)The purpose ofthis structure is to study the e ect of eliminating one ofthe composition control loops.The re uxratio is ÿxed.The hexene purity ofthe bottoms is controlled by manipulating the vapor boilup (Fig.6B).4.3.CS5-RR (single-end temperature)In this structure,there are no composition analyzers.A temperature in the stripping (or rectifying)section is controlled by the reboiler heat input.The re ux ratio is kept constant (Fig.7A ).The location ofthe temperature con-trol tray is selected using the singular value decomposition method (Moore,1992,Chapter 8).722M.A.Al-Arfaj,W.L.Luyben /Chemical Engineering Science 57(2002)715–733320330340350360370380390400410R369121518212427303336CN T (K)0.00.10.20.30.40.50.60.70.80.91.0R369121518212427303336CNL i q u i d M o l e F r a c t i o nposition and temperature proÿle (Design 3).4.4.CS7(dual temperature)The CS7structure was shown to work well in the methyl acetate system (Al-Arfaj &Luyben submitted for publication).In that system,two temperatures are used to manipulate the two fresh feed streams.There are two products produced in the chemical reaction ofthe methyl acetate process.The CS7structure was shown not to work in the ETBE system (Al-Arfaj &Luyben in press)because only one product is produced.The oleÿn metathesis process produces two products,so dual temperature control should work.A temperature in the rectifying section is controlled by manipulating re ux owrate.A temperature in the stripping section is controlled by manipulating vapor boilup.See Fig.7B.Singular value decomposition (SVD)(Moore,1992,Chapter 8)is used to select the most sensitive trays to be controlled.The SVD method suggests that either choice ofpairing could be used (R -x D and V -x B or the re-verse).However,SVD uses only steady-state information.M.A.Al-Arfaj,W.L.Luyben/Chemical Engineering Science57(2002)715–733723Fig.6.(A)Control structure1and(B)control structure1-RR.Fig.7.(A)Control structure5-RR and(B)control structure7.M.A.Al-Arfaj,W.L.Luyben /Chemical Engineering Science 57(2002)715–7337250.870.890.910.930.950.970.991234Time(hr)P r o d u c t p u r t i e s (m .f .)Fig.9.Response ofCS1-RR (Design 1).As expected,dynamic simulations showed that the ÿrst pairing shown in Fig.12works well.The alternative is unstable.4.5.DisturbancesA number ofdisturbances were studied,but results f rom only three are reported.These disturbances are probably larger than typical in a plant environment,but they provide a good indication ofthe robustness ofeach structure and show how well load disturbances are rejected.The setpoint tracking changes are not reported here due to the limited space,but results are similar.1.A step change of positive 25%in the fresh feed owrate (+ F ).2.A step change of negative 25%in the fresh feed owrate (− F ).3.Change in the feed composition ( z )from C =5=1:0toC =4=0:15;C =5=0:70;and C =6=0:15.4.6.Simulation results for design 14.6.1.CS1(dual composition)The control ofthe two end purities is very e ective.Fig.8shows that this structure is able to reject the feed rate disturbances and the feed composition disturbance.4.6.2.CS1-RR (single-end composition)Fig.9shows that bottoms purity is well controlled.How-ever,distillate purity moves signiÿcantly away from the steady-state level.It is interesting to compare the e ectiveness ofsingle-end control in reactive distillation with that seen in conven-tional distillation.For a feed owrate change in a con-ventional column,holding the purity in one end and keeping re ux ratio constant results in the purity ofthe other end staying very close to the desired level.This oc-curs because all the owrates vary directly with the feed owrate.However,in reactive distillation this situation no longer applies.As shown in Fig.9,the distillate purity is not maintained when a feed rate is made even if the bottoms composition is controlled and the re ux ratio is held con-stant.Changing the feed rate in a reactive column changes the load on the reactive zone.This results in a change in the fractionation required,which means the re ux ra-tio has to change to maintain the same conversion and product purities.Thus,simply holding a constant re ux ratio is ine ective in reactive distillation with single-end control.4.6.3.CS5-RR (single-end temperature)The steady-state gains between tray temperatures and vapor boilup,with re ux ratio ÿxed,show that there are two equally sensitive trays:Trays 3and 11.When Tray 3temperature is controlled by the vapor boilup,distillate purity moves signiÿcantly away from the desired level (see Fig.10A).When Tray 11temperature is controlled,bottoms purity is not maintained as shown in Fig.10B.4.6.4.CS7(dual temperature)Singular value decomposition analysis for the system with two manipulated variables (vapor boilup and re ux)suggests that the temperature on Tray 10should be con-trolled by the re ux owrate and the temperature on Tray 5by reboiler heat input.Fig.11shows the responses of the system to the three disturbances.The system is very robust,and the purities ofboth products are maintained726M.A.Al-Arfaj,W.L.Luyben /Chemical Engineering Science 57(2002)715–7330.870.890.910.930.950.970.991234Time(hr)P r o d u c t p u r t i e s (m .f .)0.870.890.910.930.950.970.990 12Time(hr)P r o d u c t p u r t i e s (m .f .)(A)(B)Fig.10.(A )Response ofCS5-RR (T3by V s )-Design 1and (B)response ofCS5-RR (T11by V s )-Design 1.reasonably close to their setpoints.The feed composi-tion disturbance produces the greatest change in product purities.Changing the pairing to control Tray 10with reboiler heat input and Tray 5with re ux owrate does not work (the column shuts itselfdown).A s expected,the poor dynamics ofthis pairing produce an unstable system.This is conÿrmedby calculating the Niederlinski Index for this pairing,which is negative.4.6.parison of dual composition versus dual temperature controlFig.12gives a direct comparison between the use of composition and temperature control.The performance of728M.A.Al-Arfaj,W.L.Luyben /Chemical Engineering Science 57(2002)715–7330.9000.9100.9200.9300.940132Time(hr)C 4 i nD i s t i l l a t e (m .f .)Time(hr)C 6 i n B o t t o m s (m .f .)Time(hr)C 4 i nD i s t i l l a t e (m .f .)Time(hr)C 6 i n B o t t o m s (m .f .)Time(hr)C 4 i nD i s t i l l a t e (m .f .)Time(hr)C 6 i n B o t t o m s (m .f .)132132132Fig.12.Dual composition control vs.dual temperature control.the dual temperature control (CS7)is dynamically better than that of the dual composition control for the feed ow disturbances.This is because the temperature sensors on the intermediate trays see the disturbances more quickly than the composition analyzers at the very ends ofthe col-umn.However,the steady-state performance of the dual temperature structure is not as good as the dual compo-sition.The product purities are not driven back to their desired levels.This is particularly true for the feed com-position disturbance,which produces a drop in purity of about 2%.These results suggest that a composition =temperature cas-cade control structure would provide the most e ective con-trol,both dynamically and at steady state.4.7.Simulation results for designs 2and 3Simulation results using the dual composition control (CS1)and the dual temperature control (CS7)are presented.The same disturbances are used.M.A.Al-Arfaj,W.L.Luyben/Chemical Engineering Science57(2002)715–7337334.7.1.Design2(high pressure)Fig.13shows that the CS1dual composition control struc-ture gives e ective control.A comparison ofFigs.8and13 shows that the deviations in product purities are less in the high-pressure design.This is because the column has more trays than in the base case.Fig.14gives results for the CS7dual temperature con-trol structure.The SVD method suggested controlling Tray 2temperature with vapor boilup and Tray24temperature with the re ux ow.Fig.14shows that this is an e ective structure,but product purity drops about2%for the feed composition disturbance.4.7.2.Design3(high conversion)Figs.15and16show the responses for the three distur-bances for two control structures(dual composition and dual temperature).Trays10and31are used for temperature con-trol.Both structures provide e ective control,despite hav-ing high product purities.The deviations in product purities are less than that in the base case.Interaction between the loops did not present any problems.5.Control comparison with other systemsThe class ofreactive distillation studied in this paper is signiÿcantly di erent from those studied in previous papers (ideal,methyl acetate and ETBE)because there is only a single feed.In the other systems,there are two reactant feed streams that must be perfectly balanced if the column is op-erated“neat”(no excess ofone ofthe reactants).In the ideal and methyl acetate systems,two internal column tempera-tures could be used as an alternative to having an internal composition analyzer because two products are produced. In the ETBE system an analyzer is required because there is only one reaction product,although the presence ofinerts in the feed require two product streams from the column. In the metathesis system,there is only one reactant feed stream.Therefore there is no need to have an internal com-position analyzer to balance the stoichiometry.The metathe-sis system is also less nonlinear than the other two systems because ofthe almost ideal VLE.6.ConclusionThree di erent designs for the pentene metathesis are studied,starting with a base case design from the literature. The use ofa cooling water in the condenser requires higher operating pressures than that used in base case.Economics favor columns with more trays than the base case.As the desired conversion increases,more trays are required in the column.Several control structures are examined for the three de-signs.Both dual composition and dual temperature control structures provide e ective control.Di erences in the per-formance for some control structures in conventional distil-lation columns and reactive distillation columns are pointed out.NotationB bottoms owrate,kmol=hD distillate owrate,kmol=hN total number oftraysN F feed trayN T total number oftraysR re ux owrate,kmol=hRR re ux ratioTAC total annual costV S vapor boilup,kmol=hReferencesAl-Arfaj,M.A.,&Luyben,W.L.(2000).Comparison of alternative control structures for an ideal two-product reactive distillation column. Industrial and Engineering Chemistry Research,39,3298–3307.Al-Arfaj,M. A.,&Luyben,W.L.(submitted for publication). Comparative control study ofideal and methyl acetate reactive distillation.Chemical Engineering Science.Al-Arfaj,M.A.,&Luyben,W.L.(in press).Control study of ETBE reactive distillation.Industrial and Engineering Chemistry Research. Chen,F.,Huss,R.S.,Malone,M.F.,&Doherty,M.F.(2000).Simulation ofkinetic e ects in reactive puters and Chemical Engineering,24,2457–2472.Doherty,M.F.,&Malone,M.F.(2001).Conceptual design of distillation systems.New York:McGraw-Hill.Luyben,W.L.(2000).Economic and dynamic impact ofthe use ofexcess reactant in reactive distillation systems.Industrial and Engineering Chemistry Research,39,2935–2946.Moore,C.F.(1992).Selection ofcontrolled and manipulated variables. In W.L.Luyben(Ed.),Practical distillation control.New York:Van Nostrand Reinhold.Okasinski,M.O.,&Doherty,M. F.(1998).Design method for kinetically controlled,staged reactive distillation columns.Industrial and Engineering Chemistry Research,37,2821–2834.Tyreus,B.D.,&Luyben,W.L.(1992).Tuning PI controllers for integrator=dead time processes.Industrial and Engineering Chemistry Research,31,2625–2628.Yu,Cheng-Ching.(1999).Autotuning of PID controllers.London: Springer.。