Process simulation—steady state HYSYS

Process simulators, steady state, dynamic, and batch, are used throughout the textbook (ASPEN PLUS, HYSYS.Plant, CHEMCAD, PRO/II, BATCH PLUS, and SUPERPRO DESIGNER). This permits access to large physical property, equipment, and cost databases... 

HYSYS and SPEEDUP PC and larger Dynamic and steady-state simulation of large processes with data base. 

Throughout this book, we have seen that when more than one species is involved in a process or when energy balances are required, several balance equations must be derived and solved simultaneously. For steady-state systems the equations are algebraic, but when the systems are transient, simultaneous differential equations must be solved. For the simplest systems, analytical solutions may be obtained by hand, but more commonly numerical solutions are required. Software packages that solve general systems of ordinary differential equations— such as Mathematica , Maple , Matlab , TK-Solver , Polymath , and EZ-Solve —are readily obtained for most computers. Other software packages have been designed specifically to simulate transient chemical processes. Some of these dynamic process simulators run in conjunction with the steady-state flowsheet simulators mentioned in Chapter 10 (e.g.. SPEEDUP, which runs with Aspen Plus, and a dynamic component of HYSYS ) and so have access to physical property databases and thermodynamic correlations. 

Polymers Plus steady-state and dynamic polymer process modeller and units HYSYS.Refinery modeling of complete refining processes including economics HYSYS.RTO-h real-time, online multivariable optimization POLYSIM steady-state and dynamic polymer process simulation... 

The various components that comprise HYSYS provide an extremely powerful approach to steady state modeling. At a fundamental level, the comprehensive selection of operations and property methods allows you to model a wide range of processes with confidence. Perhaps even more important is how the HYSYS approach to modeling maximizes your return on simulation time through increased process understanding. 

In this chapter, the principles behind the use of several widely used flowsheet simulators are introduced. For processes in the steady state, these include ASPEN PLUS, HYSYS.Plant, CHEMCAD, and PRO/n. For batch processes, these include BATCH PLUS and SUPER-PRO DESIGNER. 

Have completed several exercises involving steady-state simulation using one of the four simulators, ASPEN PLUS, HYSYS.Plant, CHEMCAD, and PRO/II, and involv-ing batch process simulation using one of the two simulators, BATCH PLUS and SUPERPRO DESIGNER. 

Be able to optimize a process using ASPEN PLUS and HYSYS.Plant beginning with the results of a steady-state simulation. 

In this chapter, the methods for shortcut C R analysis, using the results of steady-state simulations, have been described. The methods require the use of software for the solution of material and energy balances in process flowsheets (e.g., ASPEN PLUS, HYSYS.Plant) and for controllability and resiliency analysis (i.e., MATLAB). The reader is now prepared to tackle small- to medium-scale problems, and in particular should... 

Sequential modular approach has some clear advantages for process flowsheeting that explain why it still dominates the technology of steady-state simulation over the simultaneous or equation-oriented approach. Table 8.2 shows a list of pros and cons about sequential modular process simulators. In order to cope with the disadvantages, a few process simulators have improved the flow of information and avoid redundant computations. As an example, Aspen HYSYS has implemented the bidirectional transmission of information technology. 

The application of rigorous simulation packages, such as HYSYS, provides a valuable basis for the design and overall evaluation of advanced process control applications to the simulated processes. Steady state and dynamic simulations help in the process development by analysing and validating the design and/or ideas before their implementation to avoid costly modifications and to ensure safe operation. The simulation of the VCM plant is developed in HYSYS.PLANT in both steady state and dynamic modes and could be used for further economical, environmental and operational evaluations. Table 2 shows the characteristics of the VCM plant model and the detailed data and specifications of the main processes. Fig. 10 shows the process flowsheet of the simulated VCM plant in HYSYS including the main reactors and distillation columns. 

To check these findings, dynamic simulations of the process, using PI controllers, are performed with HYSYS.Plant. At steady state, the hot stream of n-octane at 2,350 Ibmol/h is cooled from 500 to 300°F using n-decane as the coolant, with F2 = 3,070 Ibmol/h and F3 = 1,200 Ibmol/h. Note that these species and flow rates are chosen to match the heat-capacity flow rates defined by [10], with Fi slightly increased to avoid temperature crossovers in the heat exchangers due to temperature variations in the heat capacities. Additional details of the HYSYS.Plant simulation are ... 

HYSYS An abbreviation for Hyprotech Systems, it is process-modelling software developed by AspenTech. It is used for steady-state and dynamic simulation of processes, process design, process performance monitoring, and process optimization across a wide range of industries and processes. 

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