Design Of Batch Processes Research Articles

Innovative designs of reactor networks from reaction and mixing principles

In the present paper an algorithmic procedure for generating innovative reactor network designs for complex reaction schemes is presented. Computational methodology is derived from the basic principles of reaction and mixing. Candidate reactor networks are generated by expanding the solution space into regions where different levels of mixing are required. Directions of extending the design space are identified by using formal optimization theory. A set of candi-date reactor networks is generated in a finite number of the solution space extensions. The derived methodology eliminates the requirement for an postulated superstructure and the use of qualitative knowledge for finding the optimal solution. With certain modifications the proposed design procedure can also be used to support the design of batch processes. The generated reactor structures are truly optimal. The proposed methodology is illustrated by an example of integrating chemical reactors into the overall process.

Generation and assessment of batch processes with ecological considerations

The BatchDesign-Kit is a software system that is aimed to support the development and design of batch processes for the manufacturing of pharmaceuticals and specialty chemicals, by integrating economic and ecological considerations. One of its three subsystems, the Process_Assessor deploys techniques and methodologies which allow the rapid generation and evaluation of alternative batch processing schemes. Using a state-transition network as the basic model of the batch process, the Process_Assessor allows the simulation of batch process, assessment of materials from the ecological point of view, and the selection of the most appropriate treatment options for the process wastes. This paper gives an overview of the character, structure and facilities of the Process_Assessor.

Dynamic simulations in the design of batch processes

This paper presents a conceptual procedure for the modeling of batch plants with posynomial expressions, and a resolution strategy for the optimization of the process decision variables, where dynamic simulation provides the parameters for the analytical posynomial expressions. With this resolution sequence, the optimization of the process decision variables remains affordable and trouble-free.

A novel model-based approach to optimization and control design of batch processes

Abstract Traditionally, many industrial batch processes have been operated according to rigid recipies, in spite of the fact that production would yield more profit or a better product if they were efficiently adapted to changes in quality and cost of the used and/or produced products, process and scheduling conditions, and so on. In this paper a approach, called the flexible recipe approach, is given, which transforms the common rather static recipes into recipes that can be easily improved and used for systematic and efficient production adaptation at the start of a batch and during the processing. To be able to use this approach in an industrial environment a practical implementation is made in the software package FRIS. A fermentation process chosen as an example shows the methods and gives an indication of the expected profit.

OPTIMAL DESIGN AND OPERATION OF BATCH PROCESSES

The economical design of continuous chemical processes to produce commodity products has reached an advanced state of development. Modern computer tools are used routinely to simulate and optimize these processes. This is not the case, however, for the manufacture of speciality products which must be made in batch operations. The continuing shift towards the production of higher value-added specialty products by the CPI has stimulated efforts aimed at developing good computer assisted design strategies for batch processes. This paper discusses the formulation of the problem for the optimal design and operation of batch processes. The batch problem differs from the continuous one in a number of important ways. First, batch plants do not operate at steady state. There are important trade-offs between the processing time and the severity (intensity) of processing in single units. Cycle time and performance trade-offs also exist among the various units in the process. Second, batch plants produce multiple products in many cases. There is often a competition for shared resources (labor, utilities, and equipment) among the various products. This paper presents a hierarchical solution approach for the design and optimization of a batch process. The approach is demonstrated by solving an example problem which illustrates the fundamental economic trade-offs.

Computational experience with dicopt solving MINLP problems in process systems engineering

This paper discusses an implementation of the outer-approximation/equality-relaxation algorithm for solving MINLP problems that arise in process systems engineering. The computer code DICOPT has been developed utilizing state-of-the-art optimization tools and a powerful modelling language. Computational experience in solving 16 MINLP problems with DICOPT is reported. Applications include design of batch processes, structural flowsheet optimization, column design, utility plant retrofit, planning, flexibility and reliability problems. Results show that DICOPT provides a very efficient tool for solving MINLP problems.

Design of multiproduct batch processes with finite intermediate storage

A heuristic procedure for the preliminary design of batch processes with or without intermediate storage tanks and for which the objective is the minimization of total equipment cost is presented. The processes may be operated in either the multiproduct or the multipurpose mode, but in which multiple products are accommodated through sequential single-product campaigns. The procedure which carries out a sequence of single variable fine searches to obtain a solution to the design problem is easy to code and use. The solutions yielded by the procedure are on an average within 1% of the optimal solutions and are obtained with small computational effort. The results obtained from the test problems also indicate that sizeable reductions in the capital cost of the equipment can be achieved by the insertion of intermediate storage tanks at appropriate locations in a plant.