Scaled Management Systems

Tapping the Sewer

The roses at Flemington’s Melbourne Cup, are maintained in magnificent bloom thanks to Australian sewer mining technology.

The Multiple Water Reuse (MWR) is a process for recycling water. It involves taking water straight from the sewer and processing it cost-effectively in-situ.

The MWR technology is being piloted at Flemington through a grant from the Victorian government’s Smart Water fund. Half the size of a standard shipping container, the unit uses three levels of localised filtration to remove bacteria, organics, salts, sewage and viruses through a novel arrangement of standard membranes, without the need for bacterial digestion.

MWR’s capacity to produce “class-A” water for $1 per kilolitre is comparable to the price of drinking water and unlike the charge for potable supply, the true costs of providing that water have been accounted for. Currently, the price of drinking water doesn’t factor in the capital cost of dams, loss of aquatic amenity, assets replacement, or provision for future technological advances.

The cost of operating the technology is also relatively small. The total energy requirement for the MWR is around 20 per cent of the $1/kL price and can be provided by a generator.

The technology was developed in conjunction with Memtech, now operating as Memcor, a division of Veolia Water. During trials, the device was run literally to destruction to investigate how and where failures occurred. The research team found that a minimum flow in the sewer was needed for the MWR to operate efficiently, advising that it should drill only into sewer mains to ensure sufficient flow.

The device is designed so it does not entirely drain the sewer, which would lead to problems within the sewerage system. Instead, it draws an amount of water that allows a continuous minimum flow.

One of the advantages is that any number of plants can operate from the same sewer. If there is a series of high-rise buildings, all the way along the sewer you can have a series of plants.

Ultimately there could be multiple MWRs drawing water from the sewer all the way to a treatment plant.

Water Group: Sewer Mining