First recycling plant for industrial used water opens

Jurong facility to purify such water for firms to reuse

By Feng Zengkun, The Straits Times, 8 Mar 2014

SINGAPORE yesterday opened its first water treatment plant to recycle industrial used water, purifying it to a higher standard for companies to reuse.

Previously, all the water, which was very contaminated, was treated to international standards and discharged into the sea.

National water agency PUB chief executive Chew Men Leong said the demonstration plant in Jurong helps to close a gap in Singapore's water loop.

The country recycles household used water into ultra-clean Newater, most of which goes to non-domestic users, such as wafer fabrication parks, industrial estates and commercial buildings.

Said Mr Chew: "Expanding our recycling options allows us to strengthen our water supply's resilience, especially against uncertainties... such as the dry spell we see today."

With the recycled industrial used water, which is not for drinking, companies can rely less on other sources of water that may be drinkable.

The new plant, set up by PUB and Japanese technology firm Meiden Singapore, can recycle up to one million gallons per day, about 5 per cent of the contaminated water generated by industries.

A planned water reclamation facility in Tuas will recycle even more of the used water using the same technology, at an amount yet to be determined.

The Tuas plant is part of the second phase of the Deep Tunnel Sewerage System for used water, to be completed by 2022.

During the industrial used water's recycling process, the dirty water is first filtered to remove large particles, and then put through an "upflow anaerobic sludge blanket" that uses bacteria to remove organic contaminants.

The partially cleaned water is then filtered through ceramic membranes.

The process is able to turn black, highly contaminated liquid into crystal-clear water, going by samples of the water at each stage presented yesterday.

PUB chief technology officer Harry Seah said combining the various technologies also results in "considerable" energy savings, partly because the bacterial process produces methane gas that can be converted into electricity.

Prior to the current dry spell, Singapore used about 400 million gallons of water a day, with 55 per cent of it going to non-domestic consumers such as factories.

By 2060, water demand is expected to double to almost 800 million gallons a day, with non-domestic use making up 70 per cent of demand.

NEWater and treated sea water are expected to meet up to 80 per cent of Singapore's total water demand by 2060, up from a maximum of 55 per cent now.