Reducing sludge volume and harnessing the resources within

Growing sludge volumes as a by-product of wastewater treatment pose both economic and environmental challenges for local authorities and operators. Regulations relating to sludge disposal are becoming more stringent as volumes increase.


Municipalities seek to reduce sludge volumes, protect the local environment and harness advanced technologies to extract and recover the valuable resources in wastewater.

Innovations in wastewater sludge treatment

SUEZ’s innovative technologies and thermal treatments help local authorities reduce sludge volume and meet stringent targets.

Sludge drying process by 6 stages

Treating sludge to Class A Biosolids

SUEZ has the expertise to treat sludge to Class A Biosolids in line with sludge pasteurisation, as per EPA* 40 CFR 503. Our treatment processes ensure that sludges are free from Salmonella and that 99.9999 per cent of pathogens have been destroyed in sanitation. The high quality final product meets local regulations and standards for sludge end-usage, and can be reused for agricultural purposes.


Eliminating the sludge produced by wastewater treatment

SUEZ’s innovative technologies and processes enable us to recover valuable resources from wastewater sludge such as nutrients, soil enhancers and fertilisers. We are also leaders in recovering biogas from sludge for the generation of renewable energy. Our comprehensive range of solutions help our customers meet and exceed their sustainability goals.


One stop shop

SUEZ is both project manager and water treatment specialist, enabling full control of all stages in the design and build of water treatment facilities.

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They trust us

Each year the Allwater Alliance delivers around 140 gigalitres of drinking water to the people of Adelaide from our energy efficient plants.

Making new resources from biosolids

SUEZ find new ways to recover valuable resources from wastewater treatment by-products.

Recovering phosphorus from sludge

Wastewater recovery offers a valuable source of phosphorus, with potential to meet as much as 20 per cent of global phosphorus demand. Our technologies convert the phosphorus present in wastewater into fertiliser products that offer superior slow-release effects over chemical fertilisers. Phosphorus recovery from sludge also offers a valuable alternative to phosphate rock mining for reduced environmental footprint, and reduce maintenance costs through controlled struvite precipitation.


Turning sludge into energy

The biogas arising from the anaerobic digestion of wastewater sludge is a powerful source of energy. SUEZ captures biogas for conversion into electricity and heat to meet the energy needs of wastewater treatment plants, homes and businesses. Refined biogas, known as biomethane, is a sustainable source of green gas for homes and businesses or biofuel to power cars, buses and commercial vehicle fleets.

anaerobic digestion plants operated by SUEZ worldwide
billion Nm3
of biogas produced each year by SUEZ facilities