Traditionally, Membrane Bioreactor (MBR) Validation is focussed on performance during commissioning when membranes are new, and the range of operating conditions are limited. As membranes age it is important to understand how MBR performance changes to have confidence in the quality of the water produced. Gathering data on the relationships between operational monitoring parameters such as turbidity and pathogen removal during the life of membranes would assist operators to understand the ongoing performance of membranes compared with initial performance.

The former Water Recycling Centre of Excellence developed the MBR Validation Protocol. This protocol was prepared as part of NatVal to provide guidance for the validation of MBRs. It proposed a tiered approach that allowed for a simplified process where log reduction values (LRVs) are claimed.

The aim of this project is to collect and review performance data from a broad range of operating MBR facilities in Australia to understand the pathogen LRV performance in relation to operating conditions and monitoring parameters; targeting a range of membrane age, integrity, performance, and control. This will allow water managers to understand and predict the ongoing performance of MBR plants compared to initial performance, informing future MBR design and also assisting in optimising membrane lifecycle planning. This research will also provide operators and regulators with greater confidence MBR operation throughout the asset life, and lower the whole of life cost of MBR ownership for water service providers by maximising the validated operating envelope.

In Australia, remote and regional communities frequently manage relatively small, isolated water treatment and waste management systems which have water quality and health risks characteristic of small-scale decentralised operations. Australian water utilities have a wealth of experience in addressing these issues, and this project gathered and documented a series of case studies from Victoria, Tasmania and the Northern Territory to form a knowledge base that can be referred to in the future.

Although water utilities recognise the value of online instruments that provide real-time monitoring capability, there are problems with visualising and interpreting datasets, and with distinguishing between data resulting from real-world changes in treatment plant operating conditions, for example changed turbidity or flow, and instrument failure. There are also challenges around instrument installation and operation. This project developed tools to support data visualisation and interpretation by building a prototype visualisation platform for analysing complex online UV spectral data in conjunction with weather and lab data (see Factsheet 2 ‘Development of an online platform’). To improve differentiation between instrument failure and real-world data a Bayesian Belief Network model was developed to analyse patterns and variations within datasets. Real operational, high turbidity data was used to demonstrate that this model could accurately identify different causes for the readings which included filter ripening, backwash and other causes (see Factsheet 3 ‘Improving decision making in water plant operability through Bayesian Belief networks’). Strategies for instrument installation and operation were illustrated through case studies.