Watercare Services leads the way in sustainable development embracing the benefits of Sonix ultrasound technology, used on the Mangere Water Reclamation Plant in Auckland, New Zealand

Watercare Services leads the way in sustainable development embracing the benefits of Sonix ultrasound technology. The Mangere Water Reclamation Plant serves the majority of the city of Auckland in North Island, New Zealand - a population of around 800,000 people - and for several months, New Zealand company Watercare Services and UK process engineering specialists Purac have been working in collaboration to find the best value, most sustainable solution to optimise digester performance following recent extensive upgrades to the plant. This is the Worlds largest cell lysis plant with 432kW installed ultrasonic treatment capacity, with provision to extend to 480Kw.

Malcolm Wilkinson is Purac Managing Director: 'The plant at Mangere has undergone recent extensive upgrades to intensify and enhance the treatment processes thereby reclaiming valuable wetland habitat and land area previously used as large oxidation ponds.

Final effluent discharge quality has also been significantly enhanced to meet the new more stringent consent levels.

By improving the digestion process using Sonix ultrasound technology, Watercare Services will be able to realise greater quantities of biogas, making better use of the co-generation facilities on site and significantly reduce the quantity of biosolids produced.

Better digestion stability will make the plant easier to operate, minimising chemical usage for activities such as sludge dewatering, lime stabilisation and foam control'.

Mark Ford is Watercare Services Chief Executive: 'When it opened in April 2003, the Mangere plant was the most sophisticated wastewater treatment plant in the southern hemisphere, featuring banks of pathogen-killing ultraviolet lights.

Now with Sonix ultrasonic cell lysis, we have yet another layer of protection for public health, and the ecological health of the Manukau Harbour.

The improved energy efficiency is consistent with the company's sustainable business development policies'.

Improvements brought about by the use of the Sonix technology will be available almost immediately.

The anticipated payback period for the investment meets Watercare Services stringent investment criteria, making this an exceptionally cost effective, as well as environmentally attractive solution for the advanced treatment of secondary sludge problems around the world.

The Sonix technology is sold through Sonico Ltd, a joint venture company between the global engineering consultancy Atkins Consultants and the process engineering company Purac.