How to "rely on the sea and eat from the sea" to save energy and reduce carbon? New ideas for zero-carbon seawater desalination explode

"Living on the sea and eating the sea" is also very useful in the field of water resources. Coastal areas have natural advantages in developing seawater desalination industry. In addition, coastal areas are mostly economically developed provinces and cities. Being able to take the lead in utilizing seawater resources is also a powerful supplement to the "open source" of freshwater resources.

Needless to say, the benefits of seawater desalination are promising. As a strongly promoted technology for increasing freshwater resources, its prospects have always been promising. Previously, the cost of seawater desalination was too high, and the treatment of high-concentration saltwater itself was also a problem, so the promotion speed was relatively slow. However, currently, seawater desalination has more economical and suitable solutions through technological upgrades and iterations, and commercial applications are also becoming more and more popular. The more extensive.

Current seawater desalination technologies include multi-stage flash evaporation (MSF), multi-effect distillation (MED), reverse osmosis (RO), electrodialysis (ED), membrane distillation (MD), normal Osmosis (FO), etc., the mainstream methods are reverse osmosis, multi-stage flash evaporation and multi-effect distillation. Globally, more than 160 countries have applied seawater desalination technology, more than 60% of which is used for municipal water supply, and nearly 30% is contributed to industry.

As far as our country is concerned, the development of seawater desalination industry has begun to take shape, but the proportion of municipal water supply is only about 30%, and more of it still meets the industrial water supply (steel and steel) in coastal areas. , petrochemical, electric power, etc.). According to the "2021 National Seawater Utilization Report", as of the end of 2021, there were 144 seawater desalination projects nationwide, with a project scale of 1,856,433 tons/day, including 45 seawater desalination projects of 10,000 tons and above, and 1,000-ton and above desalination projects. There are 52 seawater desalination projects above and below 10,000 tons.

So having said that, in addition to cost reduction and efficiency improvement, the seawater desalination industry still has room for improvement. What other directions should we focus on in the future? The industry believes that it is energy saving and consumption reduction.

Yes, seawater desalination is also a large energy consumer with considerable carbon emissions. Studies have shown that the carbon emissions of seawater desalination may be three times that of sewage recycling. In order to save energy and reduce carbon emissions, solar desalination equipment, "energy storage + desalination", "wind energy + desalination", "hydrogen energy + desalination"quo;Attempts to wait are ongoing. In 2020, Saudi Arabia also announced that it would build a new desalination plant using "Solar Dome" technology in the "Future New City" to achieve zero carbon emissions.

This idea of ​​combining seawater desalination with clean energy is a good solution at the moment. The Building Energy Conservation Research Center of Tsinghua University has also proposed the concept of "water and heat combined supply" for this purpose. It is hoped that the waste heat of thermal power and nuclear power in the northern and eastern coastal areas will be used as power and a new distillation method will be used to produce hot fresh water with a temperature of 100℃-120℃ and transport it to the terminal. In 2021, my country's first "water and heat production and simultaneous delivery" technology demonstration project jointly constructed by State Power Investment Corporation and Tsinghua University was put into operation in Haiyang, achieving "zero-carbon" heating and "zero-energy consumption" desalination of seawater, providing A new path to zero-carbon seawater desalination.

Recently, Canada’s Ocean Supercluster (OCC) organization also officially announced a “Oneka Glacier Sustainable Wave Energy Desalination” project, which will create a “Oneka Glacier Sustainable Wave Energy Desalination” project by transforming existing wave energy desalination technology. Glacier" seawater desalination system in order to achieve zero-carbon seawater desalination.

Therefore, New inspirations are constantly emerging in the exploration of "zero carbonization" of seawater desalination, which is expected to fundamentally solve the high energy consumption and high carbon content of seawater desalination. Platoon problem. Of course, the seawater desalination project itself has positive benefits for energy conservation and carbon reduction. In fact, this is the same as the low-carbon development of sewage treatment plants. In the future, the seawater desalination industry will surely experience a new round of boom. Some institutions predict that by around 2030, the global seawater desalination equipment market will be nearly 450 billion.