Multipurpose vessel fine chemicals

The development section serves as an intermediary between laboratory and industrial scale and operates the pilot plant. A dkect transfer from the laboratory to industrial-scale processes is stiH practiced at some small fine chemicals manufacturers, but is not recommended because of the inherent safety, environmental, and economic risks. Both equipment and plant layout of the pilot plant mirror those of an industrial multipurpose plant, except for the size (typically 100 to 2500 L) of reaction vessels and the degree of process automation. 

Lack of Economy in Size. Fine chemicals are manufactured in discrete campaigns in multipurpose plants. The reactor trains of these plants are similar throughout the industry. Regardless of the size of the companies, their main constituents, the reaction vessels, have a median size in the 4-6m bracket. Therefore, the unit cost per m per hour does practically not vary with the size of the company. 

The procedure described in the previous section is only applicable, if the reaction vessel considered is used for just one single process. In this case all necessary substance and system data can be obtained experimentally at a reasonable expense. In the fine chemicals and pharmaceutical industry, however, multipurpose plants are preferred. They are required in order to be able to respond adequately to the fast changing development activities and the continuously changing mass demands. During project engineering activities for such a plant the problem may arise that several hundred different syntheses are expected to be performed on this plant, of which may be half are known chemically due to current activities. 

The mode of operation (batch, continuous) and the use of a dedicated or a multipurpose plant is crucial for the choice of an appropriate ISPR configuration. The successful production of bulk products such as lactic acid requires an optimized dedicated system. This production plant has special equipment and advanced control strategies and is not very flexible. Generation of additional by-products has to be avoided. High added value, low volume products such as fine chemical or natural flavors are mostly produced in multipurpose plants. Investment in additional equipment or modifications of the reaction vessels is more difficult to justify, if just a few products need the application of ISPR. In this case, the less complex ISPR configurations 1 and 3 are preferred. Fiuthermore, the outlet of the production should also be easily adjustable to the market demand. 

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