Mixing Under Control at Unilever North Rocks

A new batch control system was recently installed in the Health & Beauty mixing plant in the North Rocks factory. The control system automates the mixing plant and controls the recipe mixing procedure. As the old control system was unsupported and unreliable, the focus of this project was to improve the reliability of the mixing plant by providing information to operators during the mixing process.

Over the past year, the team designed, programmed and tested a new system from Siemens called Process Control System 7 (PCS7). This software allowed the team to form a totally integrated control system from pre-weighing of minor ingredients and recipe handling to controlling plant equipment such as valves and motors. The system also allows batch to batch traceability and data logging of operator events as well as advance process control of temperature and pressure.

Since commissioning, the new batch control system has decreased batch cycle times and improved the process in which batches are being made. Operators no longer have to play a guessing game when problems occur in the plant which has put smiles back and their faces.

Ample planning, meeting project deadlines and a month of training leading up to installation, were the key reasons for the project’s success.

Author: Fiona Fong, Control Engineer Unilever