SCADA systems for Decentralised Wastewater Treatment and Water

Recycling

Ben Kele: CQURoss Percival: CQU

David Midmore: CQUChris Devitt: Devitt Communications

What is Decentralised Building?• Sustainable Building• Single or Multi dwellings• Can incorporate

– Water and energy efficiency – Rainwater tanks– Stormwater reuse– Wastewater treatment (grey, black and all-waste)– Water recycling

Decentralised Building • Increasing in popularity• Retro-fits common in South Australia and

Victoria (STEDS)• Major New Developments

– Greenfield construction– Water scarcity

• Considered to be profitable in the water industry

Challenges with Decentralised• Operation

– Rarely full-time operators– Shortage of trained staff (often owner)

• Monitoring– Company responsible for performance rarely

based on-site– Alarm system fraught with peril……

• Maintenance– Falls in between On-site and Centralised

More Challenges with Decentralised• Up-sizing on-site domestic system may cause problems• Site specific system often required (unique installations)• Change over time and/or special events significantly alter

wastewater generation patterns • Wastewater characteristics can differ significantly from

typical domestic– Nutrients– Limiting factors (sodicity, salinity)– Volume and production times

• Equivalent person volume– Often not based on research– Schools, Hospitals, Pubs/Taverns, Prisons

Solution SCADA (in part….)• Supervisory Control and Data Acquisition

(SCADA) • Programmed Operation

– Reduces risk of the various issues at the siteOn-line Monitoring– Real time reaction to events– Robust alarm system

• Maintenance– Detect issues before they become ‘events’

Recycled Water

• Decentralised water has major focus on water recycling

• Recycled water has different classes• Public and Environmental Health is

paramount• SCADA is an excellent risk management

tool

SCADA Issues• Costs relatively higher than in relation to a

centralised system– 10%-50% of total cost of system– Causes some people to use floats, timers, basic

printed circuits….• SCADA specialists hard to find• Lack of knowledge in the market from both

sides– Unique applications

Greenbank State School System

KEWT Channels and Cabinet Timber Plantation

Level Sensor Housing

Power and SCADA Controls

Conclusion

• SCADA solves many of the problems/issues related to Decentralised Systems

• The market is currently under-developed with both SCADA and Decentralised manufacturers needing to assess the potential