The reporter interviewed Chen Lianggang, vice president of China Membrane Industry Association, on the current situation of membrane technology and the development prospects of the industry. Chen Lianggang said that the membrane can produce clean water without pollution, bacteria and minerals needed by the original human body, which is a great innovation. For a long time, due to the high cost and high energy consumption of membrane treatment, it can only be used in a few fields such as medical dialysis.

In the face of water pollution, at the beginning of this century, Chinese scientific and technological personnel decided to develop the cheapest membrane products by starting with PVC plastic, whose price is far lower than that of common membrane materials. At that time, this was only a speculation in foreign textbooks in the 1970s.

At the beginning of 2003, this highly difficult scientific research project was included in the "Tenth Five-Year Plan", and three months later, it was successful. It developed PVC alloy tubular ultrafiltration membrane, laying the leading position of China's membrane industry in the world's membrane industry. This achievement has successively won the national "Key New Product Certificate", the first prize of "Science and Technology Award" of Hainan Province and the first prize of "Science and Technology Award of China Film Industry Association". Half a year later, when the membrane module made of PVC alloy ultrafiltration membrane appeared at the International Membrane Exhibition, the world membrane industry was shocked.

The pore size of ultrafiltration membrane is only 1/10000 of that of hair, and the filtration precision reaches 0.01 micron. It can filter sediment, rust, bacteria, viruses and macromolecular organic substances in water. The main drinking water indicators such as microorganism and turbidity are better than the standards of western developed countries. The life of filter element is more than 50 times of that of conventional water purifier, and the price is only one third of that of foreign products.

Technology is available, but the market is still difficult to open up. At that time, in the water purification equipment market, the largest profit was the large order of water purification membrane used by the waterworks, but these large orders were monopolized by international brands such as GE in the United States and Siemens in Germany.

In order to open up the market, Chinese researchers have set up Lisheng Enterprise to send equipment to customers. In June 2007, a large order came to our door. Kaohsiung Water Supply Plant in Taiwan visited and ordered 4000 membranes, that is, water purification membranes with a filtering area of 200000 square meters. At that time, this was the largest order of water purification membrane in the world's waterworks, with a total amount of 50 million yuan. The "bottleneck of major projects" was suddenly opened.

On November 1, 2009, an enterprise in Beijing participated in the international public bidding for the water purification system, and for the first time participated in the face-to-face competition with foreign big-name enterprises and stood out. In just over three years, more than 100 water plants in Japan have used Risheng's products.

With the acceleration of industrialization process, ultrafiltration membrane has become the core technology of Lisheng. In 2008, the production and sales volume of Lisheng ultrafiltration membrane exceeded 2.5 million square meters, ranking first in the world and becoming the leading enterprise in the global ultrafiltration membrane industry.

The 2010 Shanghai World Expo adopts the "activated carbon+PVC alloy ultrafiltration membrane+ultraviolet" combined process of Lisheng Enterprise, the core technology of which is PVC alloy ultrafiltration membrane. This technology can well filter all kinds of impurities produced by secondary pollution of tap water. The bacteria removal rate reached 99.999%, and the virus removal rate reached 99.99%. The water quality and sanitation standard of the Expo direct drinking water not only reached the new national standard, but also the main sanitation indicators were better than the European Union standard, providing direct drinking water for about 70 million tourists from more than 200 countries and regions.

At present, in the field of municipal water supply, the "third generation urban drinking water purification process" developed by us with "PVC alloy ultrafiltration membrane" as the core has become a mature scheme for the upgrading and transformation of water plants. In terms of sewage treatment, the ultrafiltration membrane developed by us can realize the efficient treatment of sewage. The filtration process is simple, the quality of produced water is good, and the service life is long. After treatment, the general sewage can be reused, biodegradable, reverse osmosis and other technologies can be used together, and at the same time, various sewage problems can be treated. In 2007, the product was awarded the title of "Recommended Product for Energy Conservation and Emission Reduction" by the State Intellectual Property Office.

At the same time, ultrafiltration membrane technology has also been more and more widely used in industrial water treatment, rural water improvement, domestic drinking water treatment, national defense and other fields. Today, China's ultrafiltration membrane technology has left behind Europe and the United States.

Looking forward to the industrial prospects, Chen Lianggang said that in the past decade, the global membrane market has shown a strong growth momentum. In 2011, the global membrane market sales exceeded US $10 billion. According to the "2011-2015 China Film Industry In-depth Research and Investment Strategic Planning Analysis Report" of the Prospective Industry Research Institute, China's film industry has entered a rapid growth period after more than 50 years of development. The application scale of ultrafiltration, microfiltration, reverse osmosis and other membrane technologies in the fields of energy and power, non-ferrous metallurgy, seawater desalination, water treatment, sewage reuse, medicine and food has rapidly expanded, and a number of landmark large-scale membrane water supply projects, sewage reuse projects and sea water desalination projects have been completed. The total output value of China's membrane industry has risen from 200 million yuan in 1994 to nearly 40 billion yuan in 2011.

The Environmental Planning Institute of the State Environmental Protection Administration predicted that China's investment in wastewater treatment during the "12th Five-Year Plan" and "13th Five-Year Plan" period will reach 1.05 trillion yuan and 1.39 trillion yuan respectively, of which the investment in industrial and urban domestic sewage treatment will reach 435.5 billion yuan and 459 billion yuan respectively. In this context, membrane technology widely used in sewage treatment will usher in great development in the next decade.

It can be said that since the "11th Five-Year Plan", China has been at the forefront of the world in the development of new membrane species, membrane manufacturing technology innovation and engineering application of membrane technology. At present, the National Development and Reform Commission, the Ministry of Science and Technology, the Ministry of Industry and Information Technology and other ministries and commissions have included membrane technology in the "Twelfth Five-Year Plan" major industrial technology for special support.

Driven by market demand and industrial policy, it is expected that δ In the next decade, China's membrane water treatment project will develop at an annual growth rate of 40%, and the annual growth rate of membrane product output value will also reach more than 20%. China's membrane market will account for 15% - 20% of the total demand of the global membrane market.