Servizio Comunitario di Informazione in materia di Ricerca e Sviluppo - CORDIS

Sanitation of food processing plants

There are two general results from this project: three sensors which can detect deposits on internal surfaces of processing equipment, primarily tubes and plate heat exchangers in processing plants; one ultrasonic cleaning transducer for pipes and tube heat exchangers. The ultrasonic sensor provides a means to non-invasively monitor the plant in terms of fouling on-line. Both reflectance (pulse-echo) and transmission systems were developed. The transmission system was found to offer the most promising results in terms of thickness measurement while the pulse-echo system was found to offer a yes/no indication of the presence of a film. The optical sensor is capable of estimating the thickness of fouling inside a heat exchanger, warning if major parts of fouling drops into the product upstream of the sensor, distinguishing between porous and non-porous fouling, controlling and documentation of the procedure and warning if foam or air is present in the system. The vibration sensor is developed as an integral part of a plate in a plate heat exchanger to detect when the fouling of critical points in the heat exchanger has reached a degree of fouling so that cleaning processes are necessary. Investigations showed that it is possible to reduce greatly the cleaning procedure time during the removal of deposit from the internal side of pipes by use of the ultrasonic cleaning transducer as well as to minimize the use of polluting chemicals.