Enzyme für Waschmittel

The high performance of modern laundry detergents at 30 – 60 °C is only possible with specific enzymes and specially tuned enzyme mixtures. The various enzymes form complexes with the substrates (stains) and hydrolyze the fixed proteins, polysaccharides and fats. Surfactants rinse resulting fragments into the wash liquor. The enzymes are produced by appropriate microorganisms in fermenters with a size of 40 to 125 m³. The microorganisms secrete the enzyme into the medium. After the end of the fermentation, the enzymes are separated from the microorganisms, concentrated and converted into the final product. Here, the enzyme solution is used as granulation liquid. Product safety requires a special coating. The product design is determined by the protein engineering (performance) and the design (convenience) of the particle.     

Einsatzkriterien für Dekanter

Criteria for the use of decanters . This survey intends to help the chemical engineer having no special prior knowledge to consider the development of a decanter and where appropriate to conduct design experiments with the aid of a producer and a hired machine. In compliance with the various stages involved in process design, the first section relates to general guidelines, the second one to laboratory experiments, and the third one to pilot experiments. The fourth section then summarizes the possible inferences of the individual experiments, and demontrates the gaps in our present knowledge.     

Optimierungsstrategien für Batchreaktoren

The successful development of a new fine chemical always comprises the selection of a synthesis process including the appropriate reactants, solvents, catalysts and so on. The operating strategy - i.e. the operating conditions - of the synthesis has to be established in order to obtain optimum quality. The present paper reviews the optimization strategies for batch reactors in fine chemical industries.     

Rührkessel-Reaktoren für Polymer-Synthesen

Stirred tank reactors for polymerization . A general survey on stirred tank reactors and cascades of stirred tanks in industrial polymerization (bulk, solution, precipitation, grain and emulsion polymerization) is presented. Special consideration is given to the various designs of both agitator and cooling devices. Scale-up problems arising from the multitude of process functions (homogenisation, suspension, dispersion, promotion of heat transfer) carried out in a stirred vessel are explained and the divers methods of indirect cooling (jacketed tank, internal coil, external heat exchanger) as compared to evaporative cooling are assessed. Finally, safety measures in operating polymerization vessels are discussed.