Diagnosing the condition of washing and rinsing liquids with a new surfacemeasurement technique

To monitor and control processes, it is necessary to diagnose the status of its determining process variables. To do this a measuring technique is req uired that allows direct on-line measurement during the process. A technical university and a professional supplier are working together on sensor technology and procedures that can be employed to diagnose washing a nd rinsing processes. The measured variable "surface tension" is used to de termine the process variable "surfactant concentration", which serves as an indicator for the detergency of the washing liquid or cleanness of the rin sing water. By using online tensiometers, developed on the basis of this new measuring technique, process analyses have been carried out. These process analyses f orm the basis for theoretical process models. In conjunction with in-proces s measuring techniques being developed, these theoretical process models ca n be used to diagnose and control washing and rinsing processes.