In an Australian first, Sunshine Coast Council is installing a high-tech pneumatic underground automated waste collection system in the new Maroochydore City Centre. As an alternative to standard kerbside bin collection services, general waste and comingled recyclables generated within the Maroochydore CBD will be transported from public place bins, residential buildings and commercial premises at up to 70km/h through a 6.5km network of underground pipes to a collection station located in the outskirts of the city centre.
Sunshine Coast Council Waste and Resources Management Branch Manager, John Hogg, said the Automated Waste Collection System (AWCS) was a more efficient alternative to conventional waste collection, helping to create a cleaner, healthier and more attractive city centre.
“The AWCS will significantly reduce the number of large vehicles needing to access the city centre, as the need for conventional waste collection trucks to service bins will be removed, benefitting traffic and amenity,” Mr Hogg said.
“This will provide a safer and more pleasant urban environment and will also reduce the carbon footprint associated with this essential service.”
The AWCS is fully sealed to minimise odours normally associated with waste management, and by eliminating early morning on-street garbage collection also creates better urban living conditions.
The system is designed by Swedish-founded company Envac and has been successfully installed and used in new urban development’s worldwide including in Stockholm, Seoul, Barcelona, London, Singapore and Beijing.
How the AWCS will work
AWCS inlets for general waste and recyclables are being installed in each building within the new CBD. Public place bins strategically located around the city centre are also linked to the AWCS pipe network to cater for disposal of general waste and recyclables.
“Residents and businesses in the Maroochydore City Centre will be provided with an education toolkit advising how to use AWCS inlets and how to recycle right. Public place bins will be clearly marked for recycling or general waste,” Mr Hogg said.
The AWCS pipe network is deemed a utility service, similar to water supply and sewerage. The network forms a tree-like layout through the CBD where the collection station is the root with the pipes branching from the main trunk line to deliver an AWCS utility stub to the boundary of each developable lot and each public place bin.
The steel pipes incorporate an anti-corrosive external protective coating. Pipe internal diameter is 400mm with pipe wall thickness varying between 6.35mm and 60.4mm depending on location. High wear and tear areas such as bends are thicker to allow for the abrasive nature of some waste materials.
To minimise cost, the pipe network and inspection pits for maintenance access are simultaneously installed in underground service corridors with other utility services (water, sewerage, electricity etc.).
The ‘engine room’ of the AWCS is the collection station which is located on the outskirts of the CBD. The collection station was designed to complement the format and standard of surrounding commercial developments. Its proximity to neighbouring properties meant soundproofing the building for noise attenuation and installing a state-of-the-art air filtration plant to prevent odour emissions.
The collection station houses most of the AWCS equipment including a series of centrifugal fans (exhausters) powered by 110kW three phase motors for creation of vacuum, waste cyclones for separation of waste and conveying air, dust cyclones with filter elements for cleaning the conveying air before it is released, a gantry crane for lifting and moving container bins, air pipes, valves, silencers, and other auxiliary equipment. To ensure seamless continuity of service delivery, a backup generator is also located on-site for use in the event of power blackouts.
From disposal inlets located throughout the CBD to the collection station bin storage area, the entire system is airtight. Material from each waste fraction is sequentially extracted from disposal inlets, transported through the pipe network and deposited into a series of 30m3 container bins located on the ground floor of the collection station.
Four container bins are housed on-site. Two ‘active’ bins are connected to respective waste fraction compactors and two spares are stored ready for swap over when active bins are disconnected for transit to and from disposal facilities.
When a container bin is at capacity, the gantry crane transfers the bin to an internal bay for loading onto a standard hook-lift haulage truck for transport to Council’s recycling facilities or landfill. Haulage trucks will access and egress the site from a road adjacent to the city centre, thereby avoiding any travel through the CBD.
Electronic monitoring and control
The collection station is also home to an electronic monitoring and control system, which identifies and draws stored waste from respective inlets on a priority demand process.
The AWCS uses a programmable logic controller (PLC) and a supervisory control and data acquisition (SCADA) system developed by Envac, known as the Envac Automation Platform (EAP).
The EAP will be continually updated with statistical data relating to waste disposal behaviour across the entire system through a series of sensors installed in individual waste disposal points which constantly monitor the system and provide real-time intelligence regarding user activity and inlet status including available storage capacity.
Using this data, adaptive algorithms ensure that the self-learning system continually fine-tunes the frequency and sequencing of disposal point emptying and adjusts the scheduling of container bin retrieval from the collection station to ensure a balanced operation that optimises automation, reduces energy consumption and minimises operational costs. Management and oversight of the EAP can be undertaken on-site or remotely.
A staged build
Mr Hogg said the project was well underway with stage one of pipe installation and collection station building works (including the fit out and installation of plant and equipment) completed earlier this year.
“Further pipe network installation aligned to the future stage civil works program will take place south of the main CBD Corso,” Mr Hogg said. “A commissioning date for the system is yet to be confirmed. The Coronavirus pandemic has restricted some travel.
“Subsequently, the international technical experts with detailed system knowledge are unable to come to Australia at this time and this may delay the commissioning of the Automated Waste Collection System.
“A collaborative approach between civil works contractors, the proprietary equipment supplier (Envac) and Council has ensured all system challenges are effectively overcome, relying on iterative sequencing and programming interaction as keys to success.”