Date:January 03, 2012

Seawater Desalination

Different from the direction of the existing study on sea water desalination, this technique tries to minimize the energy consumed by the equipment and instruments during the desalination process. It is focused on studying the essence of sea water. The core technique, molecule cracking method, can resolve the critical issues faced by all the sea water desalination techniques on the market: considerable energy consumption and inferior desalted water quality. We have found the key to remove the salt in water. We try to separate hydrone and salt sundry the most effectively with the least energy consumption in a physical manner. The most pure water compared with other technique can be obtained with the lowest energy consumption.

In comparison with the existing hot method or membrane method, the technique is able to produce the water which enjoys better quality and meets the long-term drinking standard. As for the desalination technique combined with molecule cracking method, the technique is featured by the low costs, high desalination efficiency and low pollution. It can be applied to the existing sea water desalination plants very quickly to satisfy the huge water demand all over the world.

Among all the existing sea water desalination techniques, three problems as shown in Table 4-3 need resolving. However, one of the three can be resolved by the current technique.

 

Table 4-4 Problems to be Resolved for Sea Water Desalination

Problems to be resolved Brief introduction
I High corrosion of sea water and scale blockage affect the service life of the unit;
II High energy or power consumption;
III Total desalination

 

As for the first one, crystal corrosion and scale blockage have not been settled but can be relieved to different extents through different treatment modes. Blockage is more serious by membrane RO than that of distillation method. According to the distillation method, the higher the working temperature is, the lower the crystal will be. This technique is aimed at the sea water desalination by distillation under high temperature state so the blockage of technical pipeline is not as serious as the general distillation plants.

The choice of either the second or the third one is the major R & D direction nowadays. As for membrane RO, power recycling device is developed to recycle as high as 35~50% power in order to reduce the costs effectively. However, the water quality by membrane RO is inferior so the manufacturers mix fresh water and sea fresh water based on 7:3 before providing it to the mass.

The water quality by distillation method is better. In spite of multi-effect distillation, multi-stage flash or vapor compression adopted by many systems and even the upgrade of them, the considerable energy consumed by transferring hydrone from liquid state to gas state can not be recycled. The costs are relatively high regardless of the good water quality. Many manufacturers try to reduce the energy consumption by low temperature; however, the water quality becomes inferior by low temperature and pressure distillation, making it impossible to strike the balance between costs and quality. Finally, hot method is gradually replaced by membrane RO.

 

The technique is aimed at the sea water desalination by distillation. It is composed of three zones in terms of system, the structure of which is shown in the figure. The first part in the figure is distillation boiler, where our core technique is provided, making the water quality higher than the one produced by the rest techniques on the market. The second part is green energy heat source device instead of general solar panel. Our cooperator enjoys the right so that the solar energy could be absorbed the most effectively with the conversion efficiency as high as 90%. The third part is heat exchange device. It has been widely used in different fields and can match our mature technique, minimizing the energy consumption.

Table 4-5 Table of Costs Comparison

 

Water source process Costs (%) Unit water producing cost (1t)
Equipment (Note 1) Energy (Note 2) Others (Note 3)
 

Sea water

RO 33 36 31 35.67
M.S.F 42 52 6 64.65
M.E.D 37 58 5 57.97
V.C. 42 52 6 31.21
Small molecule cracking 38 25 37 8.01

Note 1: Depreciation amortization of machinery

Note 2: Power or vapor consumption

Note 3: Costs for consumables and personnel operation management

 

The technical advantages can be obviously seen in the table above. Our unit complexity is much lower than any unit that is currently used for sea water desalination. Thanks to our core technique, we can simplify the complexity of distillation unit while acquiring good water quality. The fees for the establishment and personnel management are thus also reduced. Our green energy hot source device can also reduce the energy costs dramatically.

To resolve the water quality essentially could not just depend on RO and filter element but through the physical manner, which has been universally accepted 10years ago. Through years of R & D, we demonstrate by our practice that quality and costs can be considered at the same time.