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Efficient Process Development by Combining Process Simulation and Miniplant Technique. International competition, growing ever fiercer, and product life cycles which are becoming shorter all the time demand a significant contraction times from the chemical industry, of the implementation times from the conception of a product to its market introduction. A significant contribution to rapid and cost-effective detailed planning of a new production process is provided by the combination of process simulation and an experimental technique developed within BASF AG, i.e. the „miniplant” technique. This article starts by demonstrating the importance of process simulation in the individual phases of process development. It explains the characteristic features of the miniplant technique, what objectives are pursued by employing his technique, and what advantages ccan be achieved, compared with setting up and operating pilot plants. Finally, two examples illustrate that it is possible, by combining process simulation and miniplant technique, to develop processes more rapidely and to scale them up directly from the laboratory to production level.

Economic and technological evaluation of processes. The process engineer is finding it increasingly important to evaluate a given process from the economic and technological standpoint, when developing a process or realizing an investment project. In order to demonstrate the possibility of a structured and systematic mode of procedure, a brief account is given of the available tools. Profitability can be evaluated on the basis of the accounting rate of return (ROI), the internal rate of return (dcf yield), and the ratio of equity, all measures that can be derived from an assessment of costs and economics. To take into account the uncertainty of the boundary conditions assumed, such as raw materials costs, selling prices, and plant utilization, it is advisable to carry out a risk and sensitivity analysis. Examples are given that demonstrate the possibility of both calculating and reducing the economic and technological risks.

Various approaches to process intensification can be taken at various levels. At the lowest level, it may be possible to optimise basic physical, thermodynamic and chemical processes, for example, by changing geometries and surface structures, or using catalysts, etc. At the next level, possibilities include the use of cleverly designed plant items such as spiral heat exchangers or centrifugal reactors. Finally, at the highest or process level, improvements may involve carrying out several unit operations simultaneously in a single piece of equipment or making specific process modifications. This paper uses three examples (extractive distillation, reactive distillation column, steam injection) to demonstrate the breadth of possibilities for intensifying chemical processes. The processes were all developed with the help of process simulation and verified experimentally in laboratory-based miniplants. The information gained was essential to the successful design and operation of production-scale plant.