Water is the most precious resource for sustaining life and survival of living world, but we are losing fresh water at an astonishing rate: Climate change is resulting in disappearing of glaciers and severe droughts, groundwater being pumped out faster than natural processes can replace it. Much of the world faces a hotter and drier future under climate change, according to scientists. Rainfall – including the monsoons that fortify agriculture in south Asia – will become more unpredictable. Storm surges could contaminate freshwater reservoirs.
The Overall global water demand is projected to increase by 55 percent on the way to 2050 led by countries like Brazil, Russia, India, Indonesia and China (BRIICS) to satisfy the needs of ever-growing population —a staggering 9.6 billion people by 2050. In countries like China, the largest growth rate in water use will be in the industrial and domestic sectors according to the Water Resources Group. And new fault lines are emerging with energy production. America’s oil and gas rush is putting growing demands on a water supply already under pressure from drought and growing populations.
On September 25, 2015, the global development agenda for the next 15 years was set at the United Nations General Assembly following the adoption of the Sustainable Development Goals (SDGs). Stand-alone and integrated water goal SDG6 has been included, specifically SDG 6.4 aims to “substantially increase water-use efficiency across all sectors and ensure sustainable withdrawals and supply of freshwater to address water scarcity and substantially reduce the number of people suffering from water scarcity.”
Technology solutions for Water Security
The optimum use of space technology can help curb the fast-growing water crisis around the globe, especially in countries like Pakistan that has been ranked 26th among the most water-stressed states.
“Not only the space technology provides cost-efficient methods for water management, it also accurately monitors and predicts the long-term trends of depletion of resources,” said Federal Minister for Power Awais Ahmed Khan Leghari on Friday as he spoke on the concluding ceremony of the 4th International Conference on the ‘Use of Space Technology for Water Management’. Elaborating on the technical side, the experts also discussed ways to expand the use of space technology in form of satellite-based remotely sensed data, geographic information system (GIS) and subsequent information products for better management of water resources.
“We need to use water efficiently and it can be carried out through well-defined water property rights, besides reuse of seawater through desalination and building additional water storage facilities,” the minister stated.
Engineering solutions to water shortages—including the transfer of water between rivers—are becoming increasingly common, particularly as urban water demands grow. Under China’s south-to-north diversion project, 9.5 billion cubic meters of water shall be supplied annually to the northern regions, including the cities of Beijing and Tianjin, and provinces of Henan and Hebei.
Voltea, the global leader in electro-desalination water treatment technology, was named the Breakthrough Water Technology Company of the Year by Global Water Intelligence (GWI) at this week’s Global Water Awards ceremony in Paris. GWI cited Voltea’s “successful commercialization of its CapDI© technology” as a key factor in earning the award.
“2017 saw Voltea’s capacitive deionisation (CapDI) technology take off as one of the most successful alternatives to reverse osmosis in recent years,” GWI said. “It gained significant market traction in the industrial and commercial sectors, with over 100 systems being shipped. The company also closed a $10 million funding round to further accelerate its growth, and brought the full capacity of its robotic module assembly plant in Dallas online.”
Voltea’s industrial and commercial CapDI© systems run with patented CapDI technology, which monitors incoming water quality in real time, and self-adjusts performance to ensure it delivers consistent, precise water quality. CapDI technology is a simple, two-step process wherein water flows between electrodes. The electrode surfaces are separated from the water by ion-selective membranes that allow positive or negative ions (salts) to pass. The system is tunable, allowing adjustable salt removal and continually adjusts to account for any fluctuations in feed water characteristics.
Israel has built the world’s largest modern seawater desalination plant, the Sorek Plant that provide 20 percent of the water consumed by the country’s households. Built for the Israeli government by Israel Desalination Enterprises, or IDE Technologies, at a cost of around $500 million, it uses a conventional desalination technology called reverse osmosis (RO). At the heart of the Sorek plant are polymer membranes inside tubes. When seawater is passed through the tubes and placed under pressure, fresh water is forced through the membranes, and saltier water is held back
The Sorek plant by incorporating a number of engineering improvements like large diameter pressure tubes, and highly efficient pumps and energy recovery devices has produced a desalination plant with lowest energy consumption. In the future advanced membranes made of atom-thick sheets of carbon, hold the promise of further cutting the energy needs of desalination plants. By 2016, when additional plants will be running, some 50 percent of the country’s water is expected to come from desalination. It has demonstrated that seawater desalination can cost-effectively provide a substantial portion of a nation’s water supply.
The United Arab Emirates, faced with a growing population, have invested in desalination projects and is harvesting rainwater. Australia, Singapore, and several countries in the Persian Gulf are already heavy users of seawater desalination, and California is also starting to embrace the technology
Graphene-based sieve for Seawater desalination
Desalination is another strategy, which is especially effective in coastal areas. But the process had been expensive and energy-intensive. Now, Researchers at the University of Manchester in England have developed a graphene-based membrane that filters the salt out of seawater, making it drinkable. This development could provide drinking water to millions of people who live in countries where access to fresh, drinkable water is limited. It’s also a promising discovery for South Africa – the Western Cape in particular – given the drought.
Graphene oxide membranes have already proven their worth in sieving out small nanoparticles, organic molecules and even large salts. But until now, they couldn’t be used to filter out common salts, which require even smaller sieves.
Previous work had shown that graphene oxide membranes became slightly swollen when immersed in water, allowing smaller salts to flow through the pores along with water molecules. Now, Dr Nair and colleagues demonstrated that placing walls made of epoxy resin (a substance used in coatings and glues) on either side of the graphene oxide membrane was sufficient to stop the expansion
New zero energy technology to produce drinking water
Crystal Lagoons, a patented technology developer of giant crystalline lagoons, has developed a new technology to deal with a shortage of potable fresh water, a problem that affects more than a billion people worldwide.
The experimental desalination technology project is a ‘zero energy’ solution that would use wasted energy from Northern Chile’s 12 thermo-electric plants to potentially generate enough potable water for the country’s entire population, said a statement. This wasted energy is the equivalent of eight times the world’s renewable energy capacity and has huge global potential, it said.
The technology has already been patented in the US via the United States Patent and Trademark Office’s (UNPTO) Green Fast Track programme, which gives preference to granting patents to technologies that have a high ecological impact and environmental contribution, according to TradeArabia News Service
Water Conservation Technologies
In the short term, we can’t increase our supply of water, but we can influence our consumption. The city’s ’Day Zero’ awareness campaign is targeting Cape Town citizens around how to change their behaviors. If we continue to consume water at the rate we’ve been consuming and it doesn’t rain, at a certain point in time — Day Zero — we’ll hit the 13 percent reserves, and that’s when we’ll need to take more drastic action in terms of how we allocate water.
The improvement in Water Efficiency is required, which are hovering at around 1-2% per year to address the supply-demand gap. California, for example, enacted historic new water conservation rules in 2015, mandating urban residents to reduce water use by 25 percent. Water Conservation Technologies and water conservation devices need to be adopted for the benefit of the environment and future generations like GM technologies, Micro–irrigation or drip systems, Leakage detection equipment and water consumption software.
Waterless solutions like Freedom Waterless Car Wash, water-efficient irrigation systems and horticultural software, Water efficient appliances like dishwashers, showerheads, and toilets are becoming popular.
Wastewater recovery and reuse
Wastewater recovery and reuse, on the other hand, on average uses about half the energy of desalination, and costs about half as much. Yet, while the technology exists to recover a large percent of wastewater, the world today only reuses about 4 percent of its wastewater.
Israel, despite its desert terrain, meager rainfall and population growth, currently boasts a water surplus; it is reusing 85-90 percent of its wastewater. Saudi Arabia recently announced a plan to reuse 65 percent of its wastewater. Then there’s Singapore. The island city-state is reusing 30 percent of its water — punching well above its weight in terms of water reuse policies and technologies.
Solving Singapore’s water problem by Recycling of sewage
Water security has long been a national priority in Singapore as half of its current water supplies are imported from neighboring Malaysia. “We are preparing for the day that should the water agreement expire, we should be ready to fulfill our own needs,” says Chew Men Leong, Chief Executive of the Public Utilities Board.
Singapore’s strategy for a hydrated nation is four-fold: as well as importation, it includes desalinization plants, efficient catchment of rainwater and recycling of sewage.
Country’s public utilities board has developed innovative membrane technology to treat wastewater known as ‘NEWater’. Through a four-step series of barriers and membranes, wastewater is made free of solids, microorganisms, and contaminants resulting in potable water supplies for use by humans and industry. After one decade, the technology meets 30 percent of Singapore’s water needs, with plans to triple volumes by 2060.