The Water and Wastewater industry is estimated to consume some 3.5% of the world’s energy. With such usage come opportunities to greatly increase efficiency and save resources.
In Singapore, desalination is one of the ways in which the country provides drinking water to the 5.7 million residents of the island city-state. The latest and one of the world’s most modern desalination plants, the Keppel Marina East Desalination Plant (KMEDP), was officially opened in February 2021.
Sustainability at the centre
“The facility is Singapore’s first large scale, dual mode desalination plant built with the ability to treat either seawater or freshwater depending on prevailing weather conditions,” explains Eng Kwang Goh, Executive Director for Project Management and Water Services at Keppel Infrastructure. “The plant was designed with sustainability as a central theme.”
“We aimed to build a plant that is a model of efficiency.”
KMEDP is able to produce about 30 million gallons of freshwater every day. But, since the treatment equipment is located underground, the only thing most people see of the facility is the rooftop park, intended for community recreation.
Within the highly advanced facility, several processes in particular lend themselves to energy savings, in particular desalination. “The process of reverse osmosis through high pressure treatment systems is one of the more energy intensive steps in the water desalination processes,” Goh explains, “and the entire treatment process consumes up to 70% of the total plant power consumption.”
“We are committed to enhancing energy efficiency in our efforts to mitigate climate change.”
Innovative planning and advanced technology have been combined at KMEDP to increase efficiency. “The direct coupling configuration of the ultrafiltration and the reverse osmosis system retains booster pressure, significantly reducing energy consumption by eliminating the need to use booster pumps, and thereby saving 15% of the energy used in a pumping cycle.”
Another example of sustainable planning comes from the compact dissolved air flotation system – a clarification process that uses millions of air bubbles to remove suspended matter from treated water – which reduces the footprint of the plant by 30% alone.
“Variable speed drives and motors have also seen rapid advancement in the past decade,” points out Goh, “with today’s innovative designs delivering energy efficiencies. These technologies together with process optimization could realise reductions of up to 40% in energy consumption.”
Supporting a global agenda
With an increasing global population, greater urbanization, and the growing threat of climate change, providing clean water is ever more vital. And it is easily possible to envisage more sustainable ways of supplying it thanks to projects like KMEDP that provide not only practical benefits but also encourage other companies and industries to follow suit.
“Keppel’s proactive management of our environmental impact enables us to improve resource efficiency, reduce costs and support the global climate change agenda by prioritising innovation and energy efficiency,” Goh concludes. “Keppel is well placed to support Singapore’s push towards a more sustainable water future.”