Automation plant for liquorice 

COWI was responsible for the planning and design of the electrical system, including an automation plant for sorting of raw material and for finished products. The automation plant for extruded products was designed in the TOMS Gruppen's installation department.

The finished products consist of liquorice pastilles and fruit gum. The process is based on recipes and consists of four main elements: Mixing machine for raw material, boiling house, casting plant and sub-sequent processing.

In the original production plant, certain elements of the process were automated, while other elements were manually operated. TOMS Gruppen wanted the new factory to be automated to a much higher degree to achieve a higher efficiency of the production and an improvement of the quality.

In close co-operation with TOMS, COWI has developed a concept based on a number of PLC's interconnected in a process Ethernet. The operation takes place from LCD colour monitors located in the production area.

The plant is handling approx. 80 different recipes and is able to automatically weigh the raw material (liquid or pulverized) to be used in great quantities. Raw material to be supplied in small quantities is added manually, however with an acknowledgement signal to the system. The boiling process itself takes place automatically according to a predestined time/temperature profile corresponding to the recipe in question.

A PC linked to the system handles the data collection. This PC is also used when maintaining and/or changing the programmes. It was not necessary to established an actual control room for central monitoring, the system may however be upgraded with a SCADA plant if relevant at a later date.

The production plant and the automation system have been prepared for future expansion with a Manufacturing Execution System with functions such as traceability and quality control and data exchange with TOMS' administrative system.

The plant comprises approx. 100 analogue and 350 binary input and output ports and is supplied with PLC's and operating panels of the Allen-Bradley brand.