Normally, “green” and “desalination” are two words that don’t go together. Desalination is a process that takes brackish inland or sea water and makes it drinkable.
This can be a lifesaver in countries with limited or no access to fresh water, such as Saudi Arabia or Jordan, but the processes involved gobble massive amounts of energy and produce an unfavorable amount of salt discharge, causing environmentalists to argue that desalination is not a sustainable solution to meet the world’s water needs — especially in countries that can’t afford to power the desalination plants.
Now, the Israeli desalination company IDE Technologies has introduced a greener way to pull salt from the world’s water. Putting it to the test in China, the Israeli company has created a win-win solution for the environmentally conscious Chinese: using runoff steam from a power plant to help run the desalination plant. The result is water for the power plant, drinking water for the community and salt to sell.
Runs on 50 percent less power
Created in Tianjin, China, the Israeli-built IDE MED desalination plant is the country’s largest and greenest one yet, says IDE’s CEO, Avshalom Felber. Using a process called multi-effect distillation (MED), the plant is claimed to be 50 percent more energy efficient than any other thermal desalination plant today.
In IDE MED, salt water from the sea is heated with steam and then circulated through an evaporator to create an end result of fresh water and salt.
The green element in the design is that the steam used to heat the water before the evaporation process comes from a nearby power plant, making sure that some wasted energy is put to good use.
According to Felber: “The first phase of the Tianjin project is already operating for the last year or so, at 100,000 cubic meters of water per day. Currently we are in the execution process of Phase II, for another 100,000 cubic meters. This is by far the largest desalination plant in China.”
The plant consists of four 25,000-cubic-meter units, and an additional four are underway.
Meeting China’s growing energy needs
China is considered one of the world’s fastest-growing economies. As its population westernizes, so do its industrial and household demands for power and water. People in the Beijing region alone consume 1.5 million cubic meters of water every day.
“Water shortage is a major issue in China,” Felber tells ISRAEL21c. “It has a growing population, not yet fully reaching its planned population. And the standard of living is going higher, along with water consumption. It’s still less than one quarter of the developed world, but assuming China will catch up, water shortage will be a major restriction for its economic development.”
In the China facility, located about 150 miles northeast of Beijing, the desalination plant was contracted by the state-owned energy company SDIC, which had to meet strict regulations now coming into effect in China. Any new power plant must provide its own water source, and also must allocate 80 percent of its wastewater for consumer use. This kind of aggressive policy is meant to ensure that its growing society will benefit from increased industrial growth.
An additional green benefit of the IDE plant, which can generate 15 tons of water from one ton of steam compared to industry standards of 10 tons of water from one ton of steam, is that it produces salt as a commercial commodity.
Dipping its toes into Asian market
IDE, which has already built about 400 desalination plants in 35 countries, has experience in custom-making solutions to fit climate and other special needs.
The new Tianjin plant is IDE’s first project in China, and the company is now working with a consortium of large multinationals that plan to put together competitive new tenders, with an eye toward expansion into other parts of China and into the greater Asian market.
In April, IDE picked up a major accolade when it won a 2011 Global Water Award at the Global Water Summit in Berlin. With a keynote address by former UN Secretary General Kofi Annan, the prestigious ceremony attracted hundreds of the top figures from the global water industry.