Multipurpose batch chemical plants

It is evident from the foregoing description and diagrams shown in Fig. 1,7a, b that multipurpose batch chemical plants are more complex than multiproduct batch plants. This complexity is not only confined to operation of the plant, but also extends to mathematical formulations that describe multipurpose batch plants. Invariably, a mathematical formulation that describes multipurpose batch plants is also applicable to multiproduct batch plants. However, the opposite is not true. It is solely for this reason that most of the effort in the development of mathematical models for batch chemical plants should be aimed at multipurpose rather than multiproduct batch plants. 

Rodrigues, M.T.M., Latre, L.G. and Rodrigues, L.C.A. (2000) Short-term planning and scheduling in multipurpose batch chemical plants A multi-level approach. Comput. Chem. Eng., 24, 2247-2258. 

Fig. 12.4 Multipurpose batch chemical plant plant structure and master recipes.

Fig. 12.5 Multipurpose batch chemical plant resource allocation and material flows overtime horizon.

M. C. Wellons and G. V. Reklaitis. Scheduling of multipurpose batch chemical plants 1. Formulation of single-product campaigns. I EC Res., 30(4) 671, 1991. 

D. Ruiz, J. Canton, J.M. Nougues, A. Espufia, and L. Puigjaner. On-line fault diagnosis system support for reactive scheduling in multipurpose batch chemical plants. Computers and Chemical Engineering, 25 829-837, 2001. 

Papageorgaki, S. and Reklaitis, G.V. (1993) Retrofitting a general multipurpose batch chemical plant. Industrial Engineering Chemistry Research, 32 (2), 345-362. 

Papageorgaki, S., Tsirukis, A.G., and Reklaitis, G.V. (1992) The influence of resource constraints on the retrofit design of multipurpose batch chemical plants. NATO Conference on Batch Processes. 

The interaction between the batch and the continuous parts of the plant is a major concern of plant design and operating procedures. When the production volume reaches certain levels, continuous operation may be more economical. More often, batch chemical plants are built to produce more than one product. The objective is the use of existing equipment, which becomes idle when market demands are fulfilled. These plants can be classed in one of two broad categories multiproduct and multipurpose. The difference between the two types is illustrated in Fig. 1. 

Barbosa-P6voa, A.P. and Macchietto, S. (1994) Redesign of a multipurpose batch pilot-plant with cleaning in-place (CIP) integration. Computers Chemical Engineering, 18, S277-S281. 

Most aroma chemicals are relatively high boiling (80—160°C at 0.4 kPa = 3 mm Hg) Hquids and therefore are subject to purification by vacuum distillation. Because small amounts of decomposition may lead to unacceptable odor contamination, thermal stabiUty of products and by-products is an issue. Important advances have been made in distillation techniques and equipment to allow routine production of 5000 kg or larger batches of various products. In order to make optimal use of equipment and to standardize conditions for distillations and reactions, computer control has been instituted. This is particulady well suited to the multipurpose batch operations encountered in most aroma chemical plants. In some instances, on-line analytical capabihty is being developed to work in conjunction with computer controls. 

Batch chemical processes are broadly categorised into multiproduct and multipurpose batch plants. In multiproduct batch plants, each produced batch follows the same sequence of unit operations from raw materials to final products. However, the... 

Multipurpose batch plants are considered to be the most complicated type of chemical plant with regard to production planning. On the other hand, good planning of such plants can lead to large benefits by better nesting of the batches. 

As a typical pattern of a multipurpose batch plant, the authors consider a plant with multiple floors that produces various products (e.g., fine chemicals or dyes) in batches and/or semicontinuously. Raw materials are entered into premixing devices and placed together in a reactor where the chemical reaction takes place. The resulting product is separated from the mother liquor by a filter press and then packaged in various types of packaging. The mother liquor is stored and eventually recycled. The same product may even take different paths through the plant by use of alternate devices or production lines. 

Batch microwave reactors, reactions in, 16 554-555 Batch mixers, 16 721 Batch mononitrotoluene process, 17 265 Batch multipurpose plants, for fine chemical manufacture, 11 427 Batch nitrobenzene process, 17 252 Batch-operated settling tanks, 22 59 Batch pilot plants, 19 458 Batch plants, certified, 20 703 Batch polymerization, of vinyl acetate, 25 608... 

Quantitative failure frequency data are difficult to obtain for multipurpose batch plants in the way that they are often used in the fine chemicals and pharmaceutical industries. Moreover, a quantitative assessment requires detailed knowledge of the control instruments, which may not be available during process development Therefore, a semi-quantitative approach is proposed, providing the required reliability for future plant equipment. 

T. Pinto, A.P.E.D. Barbosa-P6voa, A.Q. Novais, 2003, Comparison Between STN, m-STN and RTN for the Design of Multipurpose Batch Plants, Computer Aided Chemical Engineering, Vol. 14, Editores A. Kraslawski e I. Turunen, Elsevier, 257-262. 

Carvalho, S.H.V. and Soletti, J.I. (2000) Retrofit design of multipurpose batch plants with multiple prodnctionioutes. Brazilian Journal of Chemical Engineering, 17 (4—7), 1015-1022. 

Voudouiis, V.T. and Grossmann, I.E. (1996) MILP model for scheduling and design of a special class of multipurpose batch plants. Computers Chemical Engineering, 20 (11), 1335-1360. 

Specialties multipurpose chemical plants, batch reactors, etc. 

With regard to the characteristics of the Schedule 2 plant sites inspected, the Secretariat has noticed a wide range of equipment configurations. Based on the list of inspectable Schedule 2 plant sites, 60% are multipurpose-batch, 27% are dedicated-batch, and 13% are dedicated-continuous. The equipment in the multipurpose-batch configurations normally have greater flexibility to produce, process, or consume a wider range of chemicals. 

Sundaramoorthy, A., Karimi, 1. A. (2005). A simpler better slot-based continuous-time formulation for short-term scheduling in multipurpose batch plants. Chemical Engineering Science, 60,... 

In specialty chemicals, the majority of plants are multi-product or multipurpose plants operated in batch mode. Only a relatively small proportion of products is produced in continuous production plants. This might change however, once current development activities ongoing in the area of flexible, continuous production technology for small production volumes (micro-reaction technology) find their way into industrial production systems.13 So far, this technology is mostly employed in pilot-plant - scale production trials, but further improvements are to be expected in the near future. 

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