CLEAN-IN-PLACE OPERATIONS FOR THIN-CAKE FILTRATION TECHNOLOGIES

摘要

In many chemical and pharmaceutical processes, solid-liquid separation, cake washing and drying steps directly impact the effectiveness of the production operation. Process engineers devote much of their time to analyzing these steps. The solid-liquid separation step can be by pressure, vacuum or centrifugation as well as in a batch or continuous mode. In this separation step, there is a further choice both of the type of filter media and the thickness of the cake or the cake depth during which the separation occurs. Cake washing generally follows and the choices are displacement or reslurry options. Finally, drying may be necessary and there are many possibilities including vacuum, convection, spray, steam and a combination of techniques. This article discusses the choice of thin-cake (2 – 25 mm) separation technologies and their benefits to optimizing the effectiveness of the production process. The paper continues with a discussion of clean-in-place operations to meet current Good Manufacturing Practices (cGMP) guidelines including riboflavin test and validations. ANSI/ISA S88 (and IEC 61512-1 in the international arena) batch process control system standards are also examined. Finally, factory and site acceptance testing is described.