Water Project of the Year
Jiaxing Drinking Water Upgrade, China
What is it?
The largest nanofiltration (NF) drinking water plant in the world, deploying microfiltration (MF) as well as nanofiltration in a radical overhaul of an existing treatment plant. The project completed in 2022 comprised 300,000m3/d of capacity, with a second stage expected to start construction this year. The total cost of the two stages will reach RMB938 million ($136 million).
Who is involved?
The project was delivered by engineering, procurement and construction contractor Shanghai Municipal Engineering Design and Research Institute (SMEDI) for its client, Jiaxing Water Co., which owns and operates the facility. Tianjian Water was responsible for equipment installation, while NF membranes were provided by DuPont (83%) and Veolia (17%) and MF membranes by Pall.
What makes it special?
The project was the first to couple MF and NF in the Chinese municipal market, ensuring system security and reliability in an environment of uncertain raw water quality. The compact design eliminated intermediate water takes, supply pumps and filters, enhancing energy savings and resulting in a compact physical footprint that reduced land requirements by 60% and capital cost by 15%.
The innovative nanofiltration system incorporates a concentrate recirculation process to maintain an optimum flow velocity across membranes, greatly reducing fouling. Meanwhile, the ability for each of the three stages of the process to flush and discharge separately reduces down time and the amount of cleaning chemicals needed while extending the lifetime of membranes significantly.
The incorporation of DuPont’s nanofiltration membranes specifically designed to address pollutants in municipal drinking water sources allowed the project to unlock a new raw water source from the Qiandao Lake, boosting Jiaxing’s water security and offering a new model for water supply for China’s growing population.
Distinction
Dumai City WTP, Indonesia
What is it?
An IDR107 billion ($7 million), 3,000m3/d upgrade to the conventional Dumai City Water Treatment Plant on the island of Sumatra in Indonesia, using nanofiltration to treat water for potable purposes from the local Masjid River.
Who is involved?
The plant was commissioned by local utility PDAM Dumai. The hollow fibre nanofiltration system was supplied by NX Filtration, under the auspices of main contractor PT Bayu Surya Konstruksi.
What makes it special?
By using nanofiltration to remove colour and pollutants from the water, the upgrade turned the river water supply from an undrinkable and potentially dangerous source into a crystal-clear and safe drinking water supply. Eliminating over 99% of colour in the water means it can be chlorinated risk-free, without the worry of turning colour compounds into potentially carcinogenic trihalomethanes.
Deploying a single, robust membrane step avoids the need for pre-treatment and reduces the amount of chemicals required for treatment by as much as 85% compared to alternative processes. Reducing opex to just $0.19/m3 and energy consumption to 0.3kWh/m3 made the project a low-cost and low-footprint solution in a financially and environmentally sensitive part of the world.
The project stands as a model for a host of countries where coloured water is an issue. By improving water sources for the population and strengthening the operational performance of water service providers while maintaining a sustainable environment, the plant achieved environmental benefits that helped it secure the financial support of the World Bank through its National Urban Water Supply Program.