The new Water Corporation owned Kwinana Water Reclamation Plant (KWRP) is Australia's largest municipal wastewater reuse plant, and one of the country's most comprehensive application of the PROFIBUS philosophy to date. PROFIBUS DP and PA communications are integral to the plant's success in improving both water efficiency in the Perth basin, and environmental management in the Kwinana industrial area. The application of fieldbus technology within plants is key to Water Corporation's 'big picture'.
The plan is to intelligently connect the 5 largest water treatment plants within a 50km radius of Perth and have after hours operation from a centralised operations room at Leederville. To be successful it is critical that an operator in Leederville can perform detailed diagnostics of any instrumentation or control problem, and then decide what action is required. PROFIBUS on the plants makes much of this possible.
John Holland Engineering was contracted to deliver the project and they engaged Veolia, a leading water and wastewater specialist engineering company, to undertake the process design and commissioning of the plant; electricals and instrumentation were contracted to PCT, and maintenance is handled by KBR Water Services, the Corporation's maintenance provider. 'We chose PROFIBUS because we wanted a fieldbus technology that would enable us to optimise our management decisions, and support our long-term aim of networking our major plants ? initially in the Perth area, and ultimately, across the whole state,' comments Dennis Yovich, Principal Engineer, Electrical, in the Corporation's Mechanical and Electrical Services Branch.
Western Australia's many water treatment plants ? plus over 980 pumping stations ? are spread across 2.5 million km. 'We need to maximise the information we obtain from these remote sites,' comments Yovich. 'Measurement and control equipment is becoming more sophisticated, there are less and less people available in the remote sites, and the time and distances to reach some of the plants are excessive. In the event of a problem, we firstly need to know that a problem exists and then we need to access the problem area to analyse what has to be done, who has the necessary skills, and what spares and equipment are required should our tradesmen need to travel to site.' PROFIBUS represents the ideal solution ? for example by enabling centralised maintenance staff to remotely re-range a flow meter, to understand the precise nature of the service required by a distant analyser unit used for measurement of disinfection properties of water, or to be alerted to a faulty gas leak detector anywhere on the network.
Water Corporation has been implementing PROFIBUS DP and PA networks for years
in its water and wastewater treatment plants. It will become an integral part of its planned networking of all the metropolitan water treatment plants over the next five years. 'The integration of digital I/O, utilising ASi bus, in the PROFIBUS world ? such as alarms, chlorine gas leaks, chlorine residual, low level alarms, empty pipe detection ? is exceptional. We use ASi bus combined with PROFIBUS PA, making all analogue measurement ? such as flow, temperature, pressure, level ? and digital switching, completely homogeneous. This homogenity is a unique advantage of the Profibus system, and makes so much more data available,' says Yovich. 'The more information we have, the better management decisions we can make ? enabling us to boost our management and maintenance efficiencies in unprecedented ways, optimise our processes and, ultimately, to pass on big savings to end-users.'