今天是2024年05月05日
High performance membrane materials are strategic high-tech industries supporting the development of water resources, energy, traditional industrial upgrading, environmental pollution control and other fields. At present, China has become one of the most important production countries of reverse osmosis membrane in the world, accounting for 18.98% of the production, second only to the United States.
China's membrane industry has formed a 200 billion scale, trillion development prospects. However, the large-scale application of membrane products in the field of water treatment is still far away from developed countries, and there is still room for improvement. Recently, Gao Congyi, academician of Chinese Academy of engineering and founder of Institute of membrane separation and water science and technology of Zhejiang University of technology, received an exclusive interview.
Gao Congyi, academician of Chinese Academy of engineering and founder of Zhejiang University of technology membrane separation and water science and Technology Research Institute
01“十四五”，多种膜技术应用水平将整体提升01 "fourteenth five year plan", the application level of various membrane technologies will be improved as a whole
[CCN] in the major consulting project of "new material powerful country 2035 strategic research" promoted by China Academy of engineering, high performance membrane separation materials are listed as the key development focus and main direction of national strategic materials, including: water treatment membrane material, special separation membrane material and gas separation membrane material. In terms of these three areas, what is the status of China's technical level in the world? What key technologies have not been broken through?
[high Congyi] China has made great progress in three fields, namely, water treatment membrane material, special separation membrane material and gas separation membrane material. The technical level can be in line with international standards in general, and the demand of various domestic industries can be solved. But in some high-end applications, such as large-scale desalination and difficult water treatment, it generally relies on foreign technology. In some basic raw materials, domestic technology still can not meet the requirements of industrialization, and the performance indexes of different batches of products fluctuate, and there are still limitations in large-scale preparation and application.
[CCN] in 1997, you led the construction of the first reverse osmosis composite membrane production line in China, which greatly reduced the price of imported membrane. What is the gap between domestic and imported RO membranes? What are the main application fields of reverse osmosis membrane in China? During the 14th Five Year Plan period, which area of development opportunities do you most favor?
Compared with foreign RO membrane, the gap in China is that the quality of mass production will be different, which is not as stable as that of foreign countries. The desalination rate of RO membrane in foreign countries can reach 99.7% - 99.8%, while the desalination rate of RO membrane developed by our country is only about 99.3%.
In the face of the strong competitive advantage of foreign companies, the domestic enterprises should master the core membrane technology, accelerate the research and development and innovation of RO membrane. In the future, domestic should focus on the production technology of independently controlled desalination membrane, energy recovery device and high-pressure pump, and occupy some markets. At the same time, the equipment structure should be further optimized, low-grade heat energy should be better used for comprehensive utilization of seawater, and the cost should be further reduced. In the aspect of seawater circulating cooling, the main problems are reducing cost and improving structure, and the research of preservative. In the field of marine chemical industry, new varieties should be added.
At present, reverse osmosis membranes are mainly used in the following applications:
一是固-液分离，如催化剂的生产、洗涤过滤、回收等，油浆净化，渣油净化等；
First, solid-liquid separation, such as catalyst production, washing filtration, recovery, etc., slurry purification, residue purification, etc;
The second is liquid-liquid separation, such as dehydration and desalting of crude oil;
Third, gas-solid separation, such as high temperature / low temperature flue gas purification process;
Fourth, the strengthening process, such as heavy oil emulsification, hydrogenation, etc.
From the perspective of the 14th five year plan, the above areas will be improved as a whole with the development of industry, including energy, new materials, Internet and intelligent manufacturing.
02 station in the high starting point to see desalination technology
[CCN] desalination, as one of the emerging marine industries in China, has developed rapidly in recent years. What is the status quo of the development of desalination industry in China? What are the technical bottlenecks to break through? How should the future develop?
[Gao Congyi] the study of desalination in China began in 1958, when the Navy and the Chemical Institute of the Chinese Academy of Sciences cooperated to conduct electrodialysis technology research. The national sea water desalination conference war, which was carried out from 1967 to 1969, laid a foundation for the application and research of reverse osmosis, electrodialysis and distillation methods. In 1982, China built the first desalination station, Xisha Yongxing Island desalination station; in 1997, the first 500t/d RO desalination project was built in Shengshan, Zhejiang Province; 2000 In 2000, the first 1000t/d desalination equipment in China was successfully developed and put into use; shortly after that, desalination entered a period of great development, and began to be used in scale in 2000.
Although membrane technology plays an active role in desalination process, at present, the large-scale use of membrane in seawater desalination still relies on import, which needs to accelerate the industrialization development of seawater utilization technology in China.
In the future, China's seawater utilization technology should be based on independent innovation technology, supplemented by digestion and absorption; it should pay attention to capacity-building, and make technology move towards the direction of simple technology, high efficiency energy saving and clean production; strengthen the industrialization technology support system, and combine the government investment and social funds for industrialization and demonstration projects; in the aspect of government management, policies and laws should be constructed The regulatory system and technical standard system encourage the participation of enterprises, promote the development of marine utilization industry and participate in international competition.
[CCN] what is the large-scale application and development trend of China's desalination project at present?
[Gao Congyi] the main technologies of large-scale application of desalination are divided into two types: heat method (distillation method) and membrane method (reverse osmosis). The heat method was developed in the 1940s. The principle is to heat the seawater to form water vapor and obtain fresh water by cooling it; the membrane method was developed in 1960s. The principle is to filter the pretreated seawater through a kind of polymer material membrane and filter out fresh water under high pressure. From the technical point of view, the two technologies have advantages and disadvantages: the heat method has high cost and large investment, but the technology is mature and the desalination water quality is good; the reverse osmosis membrane law gradually occupies the top of the international market with the advantages of small investment, low energy consumption, low cost and short construction cycle.
Although after years of research and development, China's desalination technology has made great progress in related fields, but up to now, the large-scale desalination plant has been built and can be put into operation is still few. Therefore, to let people understand desalination, first of all, there must be a certain number of demonstration projects and appropriate publicity. Especially, the managers of cities should consider the overall layout and view the desalination of seawater from a high starting point and a high level.
03There are three problems in membrane technology in promoting green development of petrochemical industry
[CCN] what are the problems of membrane technology in helping the green development of petrochemical industry? What are your suggestions?
[Gao Congyi] at present, membrane technology has three main problems in helping the green development of petrochemical industry:
First, the petrochemical industry process is extremely complex, and the requirements for membrane properties and varieties are very high. The petrochemical industry has long process flow, complex and changeable material system, and has diverse requirements for membrane performance and variety. Therefore, the applicability of the whole process of membrane technology is very high.
Second, the development of membrane technology is not enough, so it is difficult to embed the mainstream process in petrochemical industry. The membrane technology development is still dominated by experimental research, which is difficult to meet the requirements of the mainstream process of petrochemical industry, which seriously delays the application of membrane technology in the green development of petrochemical industry.
Thirdly, the application of membrane technology in petrochemical industry is seriously restricted by related industries. The membrane industry is still lack of standards for the production and quality inspection of membrane materials for petrochemical industry, which results in uneven quality of membrane materials products, and many problems appear in the application of membrane products, which seriously hinder the healthy development of membrane technology in petrochemical industry.
[CCN] what suggestions do you have for the above problems in membrane technology?
[high level] first, from the policy level, we should encourage the promotion and application of existing membrane technology, such as molecular sieve green process, membrane reactor technology, reclaimed water reuse technology, oil and gas recovery technology, hydrogen separation technology, etc.; prepare medium and long-term strategic plan of membrane technology, and promote the laboratory research and development, engineering amplification and industrial promotion of membrane technology in an orderly manner in combination with the green development of petrochemical industry; effectively integrate The government, production, University and research resources, the establishment of a high-efficiency cooperation platform between membrane technology research and development units and petrochemical enterprises, strengthening the effect of industrial clusters, establishing the original innovation research system of membrane materials and membrane processes, and focusing on the development of subversive membrane technology to promote the green development of petrochemical industry
Secondly, from the technical level: optimize the design of membrane structure, improve membrane flux and anti pollution capacity, promote the green development of separation process of petrochemical industry; strengthen the technology development of special membrane in-situ process, promote the green development of petrochemical industry in high temperature, reaction and other harsh industrial processes; attach importance to the original technological innovation and strive to form subversive technology of petrochemical industry.
