This article is a bit tough to understand in parts, in part due to poor English, however it contains some interesting material. One will note that not only does it discuss an increased need and desire for desalination technology use in China, but it also emphasizes that when this technology is utilized in China one of the important benefits to China is improved expertise in using and understanding the technologies involved so that these technologies can be further and better utilized in the future.
This attitude is one of the keys to understanding business in China.
Peter Huston
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http://en.ce.cn/Insight/200806/04/t20080604_15727686.shtml
Seawater desalination: a sunrise industry in the 21st century
Last Updated(Beijing Time):2008-06-04 11:24
By Chen Huoqi & Liang Xiaoliang
By March 24th, the largest seawater desalination project applying a dual membrane process with daily disposal capacity of 35,000 tons has operated successfully in Yuhuan Power Plant of China Huaneng Group for two years, which means such experiences in designing, implementing and operating the large-scale seawater desalination project have been stored in China.
How should we guarantee the water for enterprises' productive use and avoid "seizing water" against local people's daily life? Yuhuan Power Plant made the decision of "getting water from seas" without hesitation, namely, all water used for both production and daily life of the power plant can be supplied by desalinated seawater with the disposal capacity achieving as high as 35,000 tons per day. However, the daily disposal capacity of most seawater desalination projects operated in China is several hundred tons or several thousand tons, lack of such a project with the daily disposal capacity of beyond ten thousand tons to be made a reference, and still less a large-scale power plant totally applying seawater desalination for water supply overseas.
On the basis of analysis and research, scientific researchers decide to have a brave try and apply such a technical art named membrane process for seawater desalination. After a careful comparison and analysis for the daily operating and performance index, the scientific researchers select such a technique named dual membrane process (i.e. ultrafiltration plus dual membrane process) developed by Beijing CNC Water Technology Ltd finally.
The membrane-process seawater desalination technique consists of such two parts as pre-treatment and desalination. The traditional pre-treatment has a long-period processing technique and a difficult operation, as long as there is a little carelessness, the content of the microbe residues in the water will be increased after the pre-treatment, and the biology in a reverse osmosis membrane will be polluted and blocked easily after the seawater enter into the reverse osmosis membrane, which will decrease the water generation rate and shorten the usage lifetime of the membrane. The new-type membrane pre-treatment processing technique has such unique advantages as a short flow, a less working process, a low energy consumption, a high production capacity, a long lifetime and a small occupation area, which does not only ensure a safe operation of the desalination system, but also lower the operation cost of the entire system greatly.
Wu Hongmei, General Manager of Beijing CNC Water Technology Ltd that takes on the design and construction tasks, introduced that they made two improvements for the former dual membrane process when designing the water-treatment technical proposal for Yuhuan Power Plant. Firstly, an submerged ultrafiltration membrane with low pressure was adopted without applying the expensive glass steel shell any more, which avoided a trivial connection between shells, and make the cleaning and installment for the membrane materials more convenient and prompt, so the cost was low, the anti-pollution performance was strong, the system integration was high and the maintenance work could be easily conducted.
As the membrane device was the core of the membrane-process seawater desalination project, occupying about 40 percent of the total investment for the project, so only this part had decreased the total investment by 15 percent to 20 percent; secondly, such energy with a high efficiency was adopted to recycle devices. The remaining pressure of the "thick" water disposed in the first phase reverse osmosis system was fairly high and such water had been drained in vain in the past, forming a tremendous energy waste, but now, they applied the energy recycling device with a 94 percent efficiency, and it would convert the energy into the material seawater depending on the water pressure but without any driving forces. The new technique process made the per ton water consumption of the system decreased by 30 percent to 40 percent than by traditional technique processes. Additionally, a standard modulization was achieved for the system design, and the production capacity was enlarged without limitation as well.
The seawater desalination project of Yuhuan Power Plant has not only supplied the entire water used in the production and daily life for the enterprise itself, but also provided a-10,000-ton per day water for the residents of Yuhuan town in reverse in the dry season, and the provided water quantity is equal to one third of the total water usage quantity of the town. Its successful operation does not only set up a good example and play a demonstrating role in broadening resources of water and reducing expenditures for China's industrial enterprises and cities in costal areas, but also lays a foundation for establishing such a large-scale seawater desalination project with the daily disposal capacity of beyond 100 thousand tons; "demanding water towards seas" is not only a realistic option for addressing the challenge of the short of desalinated water resources in China's costal areas, but also a strategic measure for realizing a sustainable usage of water resource and guaranteeing a sustainable development for costal areas.
The opportunity of developing a large-scale seawater desalination project in China has been mature, and the total investment will reach as high as RMB56 billion yuan by 2020.
China is a sea power with the costal line of 18,000 kilometers, but the total quantity of the water resources in costal areas only accounts for one fourth of that in the whole nation, and the underground water has been over exploited in part of areas, leading to a sank ground, a bake-flow seawater and a deteriorated ecological environment. Short of desalinated water has become one of the bottlenecks restricting a sustainable economic development in the local areas.
State Development and Reform Commission, State Oceanic Administration and Ministry of Finance of R.R.C, co-issued Special Programs on Seawater Usage in 2005, wherein a definite request had been made in the seawater usage for the cities and high-water-consumption enterprises in costal areas: the electric power, petrochemical, metallurgical industries in costal areas shall take desalinated seawater as a kind of industrial cooling water and a kind of purified water, and the quantity of the seawater used directly by the electric power enterprises shall occupy 85 percent of the total water usage quantity; the newly established enterprises involved in the electric power, petrochemical or metallurgical industry are requested to set up a matched project to take desalinated seawater as the purified water; a transform shall be conducted for the existed enterprises, transforming the existed tap water, purified water to the desalinated seawater, which will be regarded as the industrial purified water.
What's more, a specific strategic disposition has also been developed for the seawater desalination target of the "eleventh five-year plan" in the costal provinces, areas and cities, requesting that the desalinated seawater quantity should reach from 800 thousand tons per day to 1 million tons per day by 2010, the contribution rate for addressing the water shortage challenge in costal areas should reach 16 percent to 24 percent and the percentage of the home-made desalinated seawater should be beyond 60 percent; by 2020, the desalinated seawater quantity should reach from 2.5 million tons per day to 3 million tons per day, the contribution rate for addressing the water shortage challenge in costal areas should reach 26 percent to 37 percent and the percentage of the home-made desalinated seawater should be beyond 90 percent.
To realize such targets, the total funds from RMB41 billion yuan to RMB56 billion yuan are needed. Additionally, the state government listed the seawater desalination into A Catalogue on the Industries, Products and Technologies Encouraged to Develop Vigorously by China, A Guidance on the Key Fields for the Prior-developed Industrialized High and New Technologies Currently, and organized national debt funds to support tackling hard-nut problems in science and technology and demonstration project in terms of the seawater desalination, so the seawater desalination industry has become a sunrise industry that will hit the headlines and have prosperous business opportunities in the 21st century.
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