Given the importance of the hen in the total cost and its interdependence with other sectors of the process, hen synthesis has been extensively studied in recent decades6,9,10. In the synthesis process, decisions about level of heat recovery as. Heat exchanger network synthesis and optimisation using. Heat exchanger network synthesisa thermodynamic approach alche 71st annual meetingthe synthesis and evolution of networks of heat exchange that feature the minimum number of.
A heat exchanger is a device in which energy is transferred from one fluid to another across a solid surface. A literature very wellknown stagewise superstructure is used, but isothermal mixing assumption is not made and a timesharing procedure is adopted. Synthesis of heat exchanger networks hens is inherently a mixed integer and nonlinear. Dagde2 1 school of science and engineering, teesside university middlesbrough, ts1, 3ba, united kingdom 2 department of chemicalpetrochemical engineering, rivers state university of. The technology, when properly applied, can have implications for reactor design, separator design and overall process optimization in any plant in which energy is a significant factor. This paper presents a new synthesis method for retrofitting heat exchanger networks using a twostep procedure. R sekulib university of kentucky introduction a heat exchanger is a device that is used for transfer of thermal energy enthalpy between two or more fluids, between a solid surface and a fluid, or between solid particulates and a. The use of pinch analysis as a tool for designing optimal heat exchanger networks is investigated in this work. A heat exchanger network obtained using the pinch design method is a network where no heat is transferred from a hot stream whose temperature is above the pinch to a cold stream whose temperature is below the pinch. January 2003 proceedings of the iasted international conference on modelling, simulation and optimatization. Use of pinch analysis in sizing and integrating a heat exchanger into.
Grossmann department of chemical engineering carnegie mellon university pittsburgh, pa 152, usa abstract this paper gives an overview of the evolution of mathematical methods for heat exchanger network synthesis over the last 25 years. To achieve the minimum global cost in a heat exchangers network, energy and capital costs must be decreased. Minimum utility usage in heat exchanger network synthesis. As traditional energy supplies dwindle and their environmental effects are of increasing concerns, energy conservation is our first line of defense. Pdf heat exchanger network hen synthesis has been a wellstudied subject. Synthesis of heat exchanger networks with minimum number of units. Because of this emphasis on energy, process integration is often viewed as solely relating to heat recovery network design.
Case 20 synthesis of heat exchanger networks a comparison of methods author. The journal of the association of professional engineers of trinidad and tobago. Heat exchanger networks hen synthesis is a process engineering problem that can be mathematically characterized as highly combinatory, nonlinear and nonconvex. Multiobjective synthesis of heat exchanger networks. The process streams are drawn as horizontal lines, with the stream numbers shown in square boxes. It integrates the networks of heat exchangers, boilers, condensers and furnaces for best energy utilization. However, be careful, the minimum approach temperature may be violated. Publication iv, thus combining two innovative methods and providing a. Heat exchanger network introduction the heat exchanger network synthesis problem is one of the most studied problems in process synthesis and the development of costefficient heat exchanger networks has proven to be a challenging task.
A hybrid optimization strategy for simultaneous synthesis. Multiobjective heat exchanger network synthesis based on. In a 2 cold stream, 2 hot stream and 2 stages network problem. When the use of a heat exchanger network is considered for these tasks the optimization framework developed in this work can be implemented to calculate the cost of optimal investments. Simultaneous synthesis of heat exchanger networks with. Heat exchanger network design, monitoring and optimization. The optimization of heat exchanger networks hen is a typical minlp problem.
Heat exchanger network synthesis hens is an important part in the overall chemical process. Combining each of these resistances in series gives. The number of equipment in the network influences the capital cost. From the energy point of view, an overall process system can be viewed as three main interactive components see figure 11 that can be integrated into an operable plant aaltola, 2002. This model designs a heat exchanger network which operates at minimal annual cost and satisfies heating and cooling require ments. Optimal synthesis of heat exchanger networks involving. Multipurpose heatexchanger networks for heat integration. The subnetwork is defined as a part of the hen in which the streams have no heat transfer with the streams outside the subnetwork.
This implies that the maximum number of sizes mse of heat exchangers available is 6. The superstructure consists of two stages with eight possible exchangers. Mathematical methods for heat exchanger network synthesis ignacio e. An efficient coupled genetic algorithmnlp method for heat. Multiobjective synthesis of heat exchanger networks minimizing the total cost and the environmental impact. Thermal inertia of a heat exchanger is often negligible too. Process optimization by energy and resource analysis book online at best prices in india on.
In this paper an optimization model is presented for the synthesis of a heat exchanger network hen for multiperiod operations. Bakar sha, hamid mka, alwi srw, manan za 2014 design target selection for heat exchanger network synthesis based on tradeoff plot. Heat exchangers jordan university of science and technology. Department of chemical engineering, universitat rovira i virgili. Synthesis of heat exchanger networks with the goal of designing a structure that. The heat exchanger network chemical engineering projects. After optimization, the largescale hen is divided into several independent subnetworks automatically. Pdf interfacing heat exchanger network synthesis and.
Synthesis of largescale heat exchanger network based on. Heat exchanger network synthesis hens is an important process synthesis problem and different tools and methods have been presented to solve this synthesis problem. Interfacing heat exchanger network synthesis and detailed heat exchanger design. Summary temperatureenthalpy diagrams can be used to determine heat recovery potential composite curves can be used to target for many hotcold streams energy targets set from materialenergy balances and tmin if maximum heat recovery is to be achieved, then no heat transfer across the pinch processtoprocess. A splitmerge network structure is introduced in order not to violate the prescribed minimum ap. Heat exchanger network synthesis exploits excess heat by integrating process hot and cold streams and improves energy efficiency by reducing utility usage. Optimal synthesis of heat exchanger networks involving isothermal. Synthesis of heat exchanger networks wiley online library.
Pdf multiobjective heat exchanger network synthesis based on. Solving largescale heat exchanger network synthesis. Simultaneous synthesis approach via mathematical programming aims to find the optimal network without decomposition, which has been. Heat exchanger networks with unconstrained topology andrea toffolo department of mechanical engineering university of padova via venezia, 1 351 padova italy abstract the optimization of heat exchanger network hen synthesis still remains an open problem because of the complexity of the space comprising all the possible solutions. A heat exchanger is a device that is used to transfer thermal energy enthalpy between two or more fluids, between a solid surface and a fluid, or between solid particulates and a fluid.
Boyd st, t335, norman, oklahoma 730190628 the synthesis of multipurpose heatexchanger networks that are capable of operating two plants. Pdf on jan 1, 2012, laukkanen timo and others published multiobjective heat exchanger. Heat exchanger network retrofit design by eliminating cross pinch heat exchangers beabu k. Crosbie use of pinch analysis in sizing and in tegrating a heat exchanger into an existing exchanger network 43 issn 7924. Steadystate simulations were used to delineate the tradeoff between. For largescale hen, it is difficult to solve this problem globally. Hot streams are drawn at the top of the grid, and flow from left to. Optimization of largescale heat exchanger network synthesis problems.
Pdf the synthesis and evolution of networks of heat. Heat exchanger network hen synthesis is a mean to obtain heating and cooling by process streams energetic integration, by using heat streams to heat cold streams and cold streams to cool hot streams. Bibliography includes bibliographical references p. Two important problems in heat exchanger analysis are i rating existing heat exchangers and ii sizing heat exchangers for a particular application. This enables the heat exchanger network synthesis problem to be decomposed into four subproblems. Heat exchanger network retrofit design by eliminating. Optimum design of heat exchanger networks hen is a successful way to minimize energy consumption. Pdf optimal heat exchanger network synthesis using particle. Efficient algorithm for simultaneous synthesis of heat.
This work explores a twostep, complexity reducing methodology, to analyze heat integration opportunities of an existing olefins plant, identify and quantify reduction of energy consumption, and propose changes of the existing heat exchanger network to achieve these goals. Process optimization by energy and resource analysis on free shipping on qualified orders. Grid representation it is convenient to represent a heat exchanger network as a grid. Processenergy integration has been important for the chemical and related industries, and heat exchanger network synthesis hens has been studied extensively over the last 50 years. Yee, t f, and grossmann, i e, simultaneous optimization of models for heat integration ii. Heat exchanger network design, monitoring and optimization uma maheshwar kiran ati. Then is a heat exchanger network synthesis program that was developed by professor knopf at louisiana state university knopf,1989. Reflections on chris floudasand the heat exchanger network. However, the term is commonly used to equipment in which two process streams exchange heat with each other. Heat exchanger network synthesis combining simulated. Heuristic rules were proposed to identify the best control strategy for a heat exchanger network. Optimal heat exchanger network synthesis with operability and safety considerations.
Various studies and optimization techniques have been proposed for designing optimal network with minimum total annual cost. Pdf step by step for designing an optimum heat exchanger. Suppose, the modular heat exchangers sizes available are 10, 50, 100, 200, 500. Heat exchanger network synthesis has been one of the most popular subjects in process design over the last 50 years. The maximum number of heat exchangers mhe in the network is 8.
Reflections on chris floudasand the heat exchanger network synthesis problem dr. Two major methodologies haven been proposed for the synthesis of heat exchanger network problem, namely the sequential and the simultaneous approach. The term heat exchanger applies to all equipment used to transfer heat between two streams. Heat exchangers 73 individual thermal resistances of the system. Heat exchanger network optimization for multiple period. In the first step, the problem data for the network to be retrofitted is extracted and solved for a grassroot scenario using the stagewise superstructure synthesis method. Pinch analysis of heat exchanger networks in the crude. Summary heat exchanger network synthesis provides engineers, designers, and industrial practitioners with a howto manual for understanding the methodology for conserving energy through process integration. Heat losses or gains of a whole heat exchanger with the environment can be neglected in comparison with the heat flow between both fluid flows. It also shows the heat exchanger network design in a graphical form as the network grid diagram for visualization of the network configuration.
Design of optimum flexible heat exchanger networks for multiperiod. They decompose a complex column into an equivalent sequence of simple columns and propose to design each simple, non thermalcoupled columns. Designing a heat exchangers network hen by application of pinch analysis is an effective technique for energy integration. Heat exchanger network synthesis provides engineers, designers, and industrial practitioners with a howto manual for understanding the methodology for conserving energy through process integration. Methodologies for designing optimal heat exchanger network hen can be accomplished using pinch analysis or mathematical programming, ravagnani et al. Simultaneous process and heat exchanger network synthesis. This is mainly due to its importance in achieving energy savings in industrial processes in a costefficient way.
Mathematical methods for heat exchanger network synthesis. It was proposed a manual combination of a series of optimal designs under. We propose mixedinteger linear programming models for utility targeting and heat exchanger network synthesis that account for variable stream temperatures and flow rates as well as unclassified streams and thus can be integrated with process synthesis optimization models. Optimal heat exchanger network synthesis with operability and safety consideration ainur munirah bt hafizan a dissertation submitted in partial fulfilment of the requirements for the award of the degree of master of engineering chemical faculty of chemical engineering universiti teknologi malaysia september 2015. Exchanger analysis and design therefore involve both convection and conduction. Heat exchanger network hen synthesis is responsible for the energy integration. Hot process streams release heat cold process streams absorb heat heat exchanger network hot utilities supply additional heat cold utilities absorb extra heat formal statement of the heat exchanger network synthesis. Multiperiod design of heat exchanger networks research explorer. The simultaneous synthesis problem is solved in the following two levels. The synthesis of cost optimal heat exchanger networks with.
1491 1372 1221 347 712 666 1047 1274 958 1077 1163 863 1017 623 394 1387 1097 803 1566 879 330 759 286 1247 860 1474 157 887 1070 261 1285 942 1577 1386 1064 1173 161 1399 1283 1 225 1368 1471 1191 175 1080