Pasteurisation is a process used to preserve foods such as milk, beer and fruit juices in which the product is heated to a defined temperature and held at this temperature for a defined period of time. The ET 750 experimental plant has been specially developed for education in food technology and practical work. In addition to operating and monitoring the plant, it can be used to carry out various maintenance tasks such as calibration, replacement and cleaning of plant components.
The experimental plant consists of a storage tank, two hygienic pumps, a plate heat exchanger with three compartments, a heat retention section and a heating water circuit.
The cold product is pumped from the storage tank to the first section of the heat exchanger (recuperation) for preheating. After the pressure is increased again, the product is heated to the desired pasteurisation temperature in the second section and passes through the registered temperature measurement. If the temperature falls below this value, the quick-closing bypass is activated and the plant is operated as a circuit, which prevents contamination of downstream plant components. Once the pasteurisation temperature has been reached, the product is kept hot and thus pasteurised in the heat retention section. After passing through the heat retaining section, the pasteurised product preheats the cold product. This is followed by cooling to storage temperature in the cooling section of the plate heat exchanger. The process is cooled either via a cooling unit (not included in the scope of delivery) or via the ET 195 trainer.
All main components comply with industrial standards and allow maintenance tasks to be carried out and documented in a practical manner. This includes replacing seals and calibrating the measuring instruments.
The plant is controlled via an integrated PLC with touch screen. The experimental plant can alternatively be operated and controlled via a terminal device by means of an integrated router. The user interface can also be displayed on other terminals (screen mirroring). The measured values can be stored internally via the PLC. Students learn how to operate the PLC, including setting and monitoring process variables.
