Bundamba Advanced Water Treatment Plant, Australia


The Bundamba Advanced Water Treatment Plant (AWTP) is located in Ipswich, Queensland, Australia. The plant was built as part of the Western Corridor Recycled Water Project (WCRW) to solve the water scarcity problem in south-east Queensland.

Built at a cost of $380m, the plant can produce 66 million litres per day (Ml/d) of treated water. The recycled water produced by the plant is of very high quality and can be safely sent to water reservoirs.

Construction of the plant started in September 2006 and was carried out in two stages - Stage 1A and Stage 1B. Stage 1A was completed in August 2007 and Stage 1B in March 2008. The plant became fully operational in June 2008.

Stage 1A of the project received the Global Water Project of the Year Award from Global Water Intelligence in May 2008.

"The Bundamba plant includes pre-treatment lamella clarifiers."

Purpose of project

The Tarong and Swanbank Power Stations in south-east Queensland draw water from the Wivenhoe Dam, which is also a source of drinking water. In 2006, the region faced a severe drought, threatening the drinking water supplies.

As a long-term solution to the problem, the Queensland State Government launched the WCRW project which aims at recycling wastewater for industrial and agricultural use. It included construction of a 200km-long network of underground pipelines and three AWTPs at Bundamba, Gibson Island and Luggage Point.

Stage 1A of the project included construction of a plant at Bundamba to treat wastewater. The purified recycled water is supplied to the Swanbank Power Station through a 7.3km pipeline. The project reduced the power station's dependence on the Wivenhoe Dam and enabled it to operate and supply power to south-east Queensland.

In Stage1B of the project, the Bundamba plant was expanded to treat additional volumes of wastewater from existing plants at Oxley and Walcol.

Facilities

The Bundamba plant includes pre-treatment lamella clarifiers with the capacity to treat up to 100Ml/d of wastewater. The treatment facilities include a 5,000m² microfiltration and reverse osmosis building in which three core treatment processes are carried out to remove contaminants and impurities. Two chemical areas of the plant store 12 chemicals which are used throughout the plant.

Purified water is stored in a 20 million litre treated water storage tank. Two pump stations supply the purified water to Swanbank and Tarong power stations. An overflow attenuation tank at the plant collects spillage from the facility tanks.

The residuals area of the plant treats the biosolids from the treatment process before it is released into the Brisbane River. The area includes microfiltration and backwash tanks, solids contact clarifiers and denifitrication tanks and reverse osmosis concentrate (ROC) biological nitrification process tanks. It also includes ROC tanks and lamellas, gravity sludge thickener and sludge dewatering plant.

Treatment

The treatment process at the Bundamba AWTP includes three main steps – microfiltration, reverse osmosis and advanced oxidation. The process converts nearly 82% of the raw water into purified recycled water.

The microfiltration process involves passing the wastewater through a fibre membrane containing pores which are 0.014 microns wide. The membrane removes particulate matter, protozoa and few viruses from the water. The Bundamba AWTP uses Siemens Memcor's CP Membrane Filtration technology for microfiltration.

Following microfiltration, reverse osmosis is carried out where water is passed at high pressure through MegaMagnum MM13 reverse osmosis trains. The trains feature 65 membranes with a diameter of 18in to remove salts, viruses, pesticides and organic compounds.

The next step includes advanced oxidation process in which ultraviolet irradiation and hydrogen peroxide is used to destroy any remaining organic traces in the water.

The purified water is soft and has low alkalinity, which can corrode the piping and pumping equipment. Lime and carbon dioxide are, therefore, added to harden the water and increase its alkalinity.

The water is then stored in the treated water storage tank and sent to the power stations.

Key players

The design and construct contract for the plant was awarded to the Thiess and Black & Veatch joint venture.

Parsons Brinckerhoff Australia and Beca provided design services and Auric Consulting Group Australia provided consulting services for the project.

Multifix was contracted to construct the concrete structures including the pre-treatment facility, treated water tank, overflow attenuation tank, microfiltration and reverse osmosis building and pump stations.

"In Stage1B of the project, the Bundamba plant was expanded."

Koch Membrane Systems supplied its MegaMagnum reverse osmosis (RO) element for the plant. Siemens provided microfiltration and ultraviolet equipment. Trojan Technologies supplied the advanced oxidation system and Severn Trent Water Purification supplied denitrification filtration equipment.

Blucher Australian supplied its Mapress 316 stainless steel pressure system for the plant.

Infilco Degremont was responsible for constructing the solid contact clarifiers at the plant. Illawarra Engineering Services was responsible for fabricating and installing piping for the plant.

Gay Constructions was subcontracted to supply, fabricate and erect structural steel. D&R Stainless was responsible for stainless steel pipe spooling fabrication.

SJ Electric was subcontracted to install electrical and controls equipment at the plant. The contract included installation of 11kV main switchboard, field cabling, PLC/SCADA control system and instrument pipe work and tubing.

Downer Group installed and commissioned high voltage electrical cable and equipment at the plant.