Small insoluble particles in wastewater such as sand, coffee grounds gravel, glass and food particles.
Wollongong Water Resource Recovery Facility is one of 29 water resource recovery facilities in Greater Sydney, the Blue Mountains and the Illawarra. It serves Wollongong and surrounding suburbs.
Location: Port Kembla Road, Wollongong
Population served: 200,000 people
Area served: 71 square kilometres, including Port Kembla, Bellambi, Wollongong and surrounding suburbs
Wastewater treated: 49.8 million litres each day
Treatment level: Tertiary
Recycled water applications:
Environmental discharge: We release any remaining recycled water to the ocean, about 1 kilometre offshore.
Biosolids produced: 11,000 tonnes each year
Operating licence and regulation: We operate the plant under 3 sets of rules.
Primary wastewater treatment removes large solids using physical separation processes.
Screens trap and remove large solids as wastewater flows through.
We inject air into a tank, causing the water to spiral. The air flings the grit, such as sand and coffee grounds, to the edges. It collects in the bottom of the tank where a scraper removes it.
The grit and screenings captured are sent to landfill.
Wollongong uses 2 different types of sedimentation processes.
Traditional sedimentation allows solids to settle to the bottom of the tank while oil and grease float to the top. Scrapers at both the bottom and the top of the tanks remove the solids, oil and grease, which are treated to produce biosolids.
A multi-flow tank (sometimes called a lamella plate) uses a set of stacked inclined plates. Water travels up and over the inclined plate. The heavy solids are captured on the plate. Mechanical scrapers remove the solids, which are treated to produce biosolids.
Secondary treatment removes phosphates and nitrates using physical, biological and chemical processes. Learn more about Removing nutrients in wastewater.
Wollongong uses 2 types of secondary processes that work in a similar way:
We add a high concentration of microorganisms (activated sludge) to the wastewater. In the CONVAS, we use large mechanical aerators to introduce air into zones of the tank. In the bioreactor, we introduce the air using small diffusers at the bottom of the tank. By varying the amount of air in different parts of the tank, we ensure different types of microorganisms can break down nutrients like nitrogen and phosphorus.
The activated sludge settles to the bottom of the clarifier where scrapers remove it. We recycle some of this sludge back into the bioreactor and treat the rest to produce biosolids.
The treated water from the top of the tank flows to tertiary treatment.
Tertiary treatment uses chemical and physical processes to remove very fine solids and disinfect the treated wastewater.
Filters made of layers of sand and coal trap remove any remaining fine particles.
Wollongong uses 2 types of disinfection:
For recycled water that will be used on-site, and at the golf course, sports fields and coal terminal, we use both ultraviolet light and chlorine to kill any microorganisms that can make people sick.
For recycled water that will be discharged to the ocean, we use ultraviolet light only.
Advanced water recycling uses membranes to remove extremely fine particles, including dissolved salts, from the water.
We pass the water through a hollow fibre membrane that has a pore a size of 0.05–2.0 micron (µm). Particles larger than the pore size are trapped on the membrane and the water passes through.
We push the water through a flat-sheet, spiral-wound membrane known as a reverse osmosis membrane. The membrane pore size is 0.0005 microns. The pore size is so small that it can remove nutrients, chemicals, bacteria, viruses and dissolved salts from the water.
This very high-quality water is used by BlueScope Steel.
On our plants, we use recycled water instead of drinking water wherever we can. Hoses, sprays and filter backwashes all use recycled water. We use the remaining recycled water for a number of different things.
Wollongong City Council uses recycled water to irrigate JJ Kelly Park soccer fields and Vikings Rugby Club field.
The sports fields are within one kilometre of the Wollongong Water Resource Recovery Facility. We pump recycled water to the council's 120,000-litre storage tank, which is used to irrigate 22 hectares of sports fields.
The council uses about 5 million litres of recycled water each year. The council generally irrigates the sports fields at night to help reduce water loss from evaporation.
We supply Wollongong Golf Club with as much recycled water as it needs to irrigate the greens and fairways.
The golf club is next door to the Wollongong Water Resource Recovery Facility. We pump recycled water to the club's 2.8-million-litre storage dam, which is used to irrigate 25 hectares of the 45-hectare site. It uses about 50 million litres of recycled water each year. The amount of recycled water used varies, depending on the weather and other factors.
The club generally irrigates the course at night to help reduce water loss from evaporation.
Port Kembla Coal Terminal uses recycled water for dust suppression. It sprays recycled water on the coal to keep it damp and reduce dust as it's moved around. It has been using recycled water since 2008.
BlueScope Steel uses high-quality recycled water for steel manufacturing. Of the water it uses, 99% comes from either recycled water or salt water. It uses recycled water for cooling, dust suppression, descaling and scrubbing. Learn more about BlueScope's environmental improvement initiatives.
Eight staff manage, operate and maintain the facility. They collect and analyse water samples, do laboratory testing and manage special projects to keep it running safely and efficiently.
Three types of maintenance are required to keep the facility operating: preventative, planned and reactive.
See the table below for examples.
Prevents a breakdown
Oiling a motor
Replacing equipment as it reaches the end of its useful life, before a breakdown
Replacing a worn motor
Fixing equipment that has unexpectedly broken down
Repairing a motor
Want to visit one of our sites? We offer free excursions and technical tours to schools, universities and community groups.