Depending on the required configuration complexity, the CIP plant can carry out the cleaning of the pipes connecting the cellar to the filling machine or include in the cleaning process the whole of the machines installed between the cellar and the filler (Flash pasteurizers, premix, carbonators, etc…). The number of tanks and the automation level of the system can vary according to the customers’ needs: either the whole of the operations are manually controlled by the operator or a complex system automatically controls cleaning solution level, concentration, temperature and flow rate, cycle time parameters and discharge or recovery of the return solutions by means of a PLC.
The cleaning solution parameters are constantly monitored during the sanitization cycles by means of special devices that check conductivity, flow (delivery and return) and temperature in order to guarantee safety and hygiene.
The 3-tank CIP system consists of hot water, acid solution and caustic solution tanks.
A centrifugal pump sends the cleaning solutions out to the parts of the plant to be treated; the delivery pressure is controlled by a digital pressure transducer.
The three tanks are provided with level probes. The one at the bottom makes sure the liquid level doesn’t drop below the emergency limit.
The heating system is composed of a PT100 probe for the control of the liquid temperature, a heat exchanger and a superheated water circuit complete with recirculation pump and modulating valve for the flow adjustment.
Two titration systems are installed in the caustic and acid solution tanks; they consist of a conductivity probe and a centrifugal pump that guarantees a constant recirculation of the cleaning solution.
The data concerning working programs and cleaning solution successions are set in the control panel.
Before starting up the machine in automatic mode, the operator must make sure the correct temperature and concentration parameters have been set, together with the program to be carried out and the treatment times.
When the operator starts the automatic operation, the PLC checks the actual condition of the three tanks and carries out the preparation cycle if needed, restoring the correct level, temperature and titration parameters.
When the CIP system is ready, the unit sets itself in stand-by mode and waits for the fillers to require the cleaning solutions. The operator can select a cleaning program among those available. Each program can be composed of maximum ten independent cycles which are carried out according to the established sequence.
When the user creates a sequence he must pay attention not to select cycles which are not compatible with each other. For example, a cleaning cycle with acid solution cannot follow a cleaning cycle with caustic solution and vice versa.
However, the PLC checks that the cycle sequence is correct and advises the user in case of mistakes, guaranteeing the system safety.