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“Author of analysis of obstacles and prospects for advanced treatment of urban sewage in my country during the 11th Five-Year Plan: Su Yang During the "Tenth Five-Year Plan" period, China's water environment was still in the process of partial improvement and overall deterioration. "Lack of water and dirty water" was still a common situation. The reasons for this situation are mainly two-fold. First, there is objective "water shortage" - China's per capita water resources are inherently insufficient2, and the current development method has led to a large amount of water consumption per unit of GDP growth, resulting in over-utilization of water resources, making it difficult for natural water bodies to ensure sufficient ecological water consumption. ； The second is the subjective "dirty water" - China's urban domestic sewage and industrial sewage treatment capabilities cannot keep up with the speed of economic development, and the sewage generated by mass production and daily life cannot be effectively treated. 1. The current development trend of sewage treatment and its dynamic mechanism 1. The necessity of increasing sewage treatment. Although China’s sewage treatment rate has greatly improved during the “Tenth Five-Year Plan” period, it is still low.: In 2005, the national urban sewage treatment rate (including simple primary treatment) was 52%. * * Among the 509 cities under key assessment by the State Environmental Protection Administration, 178 have a centralized domestic sewage treatment rate of 0. The consequences of this situation are: The overall water quality of surface water in the country in 2005 was not optimistic.: exist * * Among the 744 sections actually monitored by the surface water monitoring network (including 597 river sections and 147 lake and reservoir points), the proportion of water quality sections of Class I-III, Class IV-V and worse than Class V were 36%, 36% and 28% respectively. The main pollution indicators are ammonia nitrogen, petroleum, permanganate index, etc. 75% of lakes across the country have experienced eutrophication to varying degrees. Inadequate sewage treatment further aggravates water shortages (water quality-type water shortages). The impact of objective "less water" and subjective "dirty water" is significant: According to statistics, more than 300 of my country's more than 600 cities are short of water. Cities across the country are short of 60×108 cubic meters of water per year. The reduction in industrial output value due to water shortage is estimated to be 120 billion yuan per year. Water shortage has become a major constraint on economic and social development in some regions. 2. The dynamic mechanism for increasing sewage treatment corresponds to objective and subjective causes. Currently, there are both objective and subjective dynamic mechanisms for increasing sewage treatment in China. From an objective aspect, it is the objective need of the industrialization and urbanization process. “Since the "Tenth Five-Year Plan", China has entered a period of rapid development of the heavy and chemical industry, and has continued the growth pattern of high resource consumption, which has greatly increased the water demand for industrial production. ； The urbanization rate has maintained an annual growth rate of 2%. A large number of farmers have concentrated in cities, and the consumption structure of urban residents has upgraded, resulting in a significant increase in urban water demand. Insufficient water resources have formed a sharp contradiction with the rapidly growing demand for water. While promoting water conservation, easing the self-purification pressure of natural water bodies through secondary sewage treatment and carrying out sewage reuse through advanced sewage treatment mean opening up new water sources. Therefore, it has become a top priority to solve the water shortage problem and alleviate this contradiction by increasing the intensity of urban sewage treatment. From a subjective perspective, the central government and all levels * * We have recognized the importance of intensifying work in this area and have deployed it from three aspects:: The first can be called "to deal with”: In the "Eleventh Five-Year Plan" Outline, binding indicators (i.e., the main indicators for assessing the performance of local leading cadres) are clearly proposed. One of them is that the total discharge of major pollutants should be reduced by 10% at the end of the "Eleventh Five-Year Plan" ； It is also clearly stated in the “Eleventh Five-Year Plan” of the Ministry of Construction: By 2010, all cities and counties in the country should plan to build centralized sewage treatment facilities, and the sewage treatment rate in cities nationwide should not be less than 70%. The current situation is far from this goal: By the end of 2005, my country's urban sewage treatment rate was 52%, and 135 cities had sewage treatment rates reaching or approaching 70%. But at the same time, there are still 278 cities across the country that have not built sewage treatment plants. To achieve this goal, Qiu Baoxing, Vice Minister of the Ministry of Construction, predicts that the investment scale in the construction of urban sewage treatment facilities will exceed 330 billion yuan during the "Eleventh Five-Year Plan" period. ； The second can be called "requiring in-depth processing"”: As the urban water supply situation becomes increasingly tight, the price of water supply (tap water) has increased significantly (for example, the price of tap water in Beijing has increased four times in the past five years), and the pressure and cost-effectiveness of water reuse are improving. In addition, some cities are close to closed or semi-closed water bodies with increasingly serious eutrophication, which has seriously affected urban development (such as cities around Taihu Lake and Kunming Dianchi Lake, etc.), and they must carry out advanced sewage treatment. ； The third one can be called “to be dealt with through marketization””: The reform of municipal public utilities in Chinese cities is also advancing in an all-round way under the tide of institutional reform of public institutions. It has become a common trend to solve the problems of insufficient funds, low efficiency and backward technology of urban public utilities through market-oriented methods. The Ministry of Construction has promulgated the "Administrative Measures for Municipal Public Utility Franchise" and will promulgate it during the "Eleventh Five-Year Plan" period. * * Supervision measures for water supply, drainage, sewage treatment and reclaimed water reuse to ensure that sewage treatment is increased and carried out in a standardized manner through market-oriented methods. 2. Key directions for advanced treatment of urban sewage Although my country has put forward clear requirements for the urban sewage treatment rate during the "Eleventh Five-Year Plan" period, it must be noted that in terms of the sewage treatment level targeted on the surface, these requirements are relatively low - most cities and towns can still only build secondary or even primary sewage treatment plants, and the pollutants controlled can only be limited to COD and suspended solids (SS). There are two reasons for this situation: On the one hand, China must make full use of the self-purification capabilities of natural water bodies at this stage, and it is impossible to raise sewage discharge standards regardless of national conditions. ； On the one hand, only in certain areas—for example, areas with high water quality requirements and prone to eutrophication—are there urgent requirements for in-depth treatment. Obviously, these areas are the key directions for promoting advanced urban sewage treatment in the future. Judging from the quality, quantity and demand of water resources in my country, the middle and lower reaches of the Yangtze River, several large cities with water shortages in the east, and some large cities near large areas of enclosed or semi-enclosed water bodies are such key areas. The middle and lower reaches of the Yangtze River plains, which developed under the East Asian monsoon climate, have formed a complex river-lake composite ecosystem with dense shallow lakes and intertwined river networks. It is a unique natural landscape in China. However, the shallow lakes in the middle and lower reaches of the Yangtze River are also the hardest hit areas by eutrophication, which has seriously affected production, life and biodiversity. Due to its floodplain characteristics, the lake has a higher nutrient base. This area is also an area with rapid economic development and high population density in our country. Since the 1980s, large amounts of nitrogen, phosphorus and other nutrients have been discharged into rivers and lakes along with industrial and agricultural wastewater and domestic sewage. Coupled with inappropriate human activities, this has greatly changed the cycle of lake biogenic elements. The structure and function of the ecosystem have degraded. Blue-green algae and algae blooms have occurred frequently. Water shortages have become increasingly serious, causing huge economic losses. For example, in Taihu Lake and southern Jiangsu, an algae bloom broke out in Taihu Meiliang Bay in 1991, causing 112 factories in Wuxi City to suspend production. Residents had difficulty drinking water, and direct economic losses reached 160 million yuan. Due to the increasingly serious deterioration of lake water environment and eutrophication problems, which are seriously restricting the sustainable development of society and economy, it has caused problems at all levels. * * attach great importance to: * * Among the three lakes focused on management during the "Tenth Five-Year Plan" period, two lakes (Taihu Lake and Chaohu Lake) are located in the middle and lower reaches of the Yangtze River. The Chinese Academy of Sciences predicted the eutrophication trend of typical lakes in the middle and lower reaches of the Yangtze River (Taihu Lake, Chaohu Lake and Xuanwu Lake) by applying the ecological pressure load model. The results showed that the ecological pressure for the development of eutrophication in urban lakes almost entirely comes from population pressure (i.e. domestic sewage discharge), while the ecological pressure for eutrophication of non-urban lakes comes from population pressure and land use pressure (i.e. agricultural non-point source pollution), potentially from livestock and poultry breeding pressure. With the development of society and economy, the ecological pressure load of typical lakes in the middle and lower reaches of the Yangtze River at the end of the "Eleventh Five-Year Plan" will exceed the critical load by more than 1.4 times, entering an "algae-shaped" state of heavy eutrophication (Taihu Lake) and ultra-eutrophication (Chaohu Lake). This is not only true for lakes, but also semi-enclosed water bodies around larger cities in Jiangsu, Zhejiang, Anhui, Hubei and other regions are generally in a state of eutrophication. The primary pollution indicator is ammonia nitrogen, and ecological pressure generally comes from population pressure. For eutrophication caused by population pressure, only by taking pressure reduction (advanced urban sewage treatment) measures can the water quality be improved. The current secondary sewage treatment plants can only mainly solve COD and SS pollution. Without solving the problem of excessive ammonia nitrogen emissions, it is impossible to make the water clear. Obviously, in-depth treatment of water entering lakes in the middle and lower reaches of the Yangtze River and semi-enclosed waters such as Bohai Bay and Hangzhou Bay is urgently needed to prevent eutrophication and restore water body functions. Moreover, for water-scarce areas, advanced treatment is the leading process for producing recycled water, which can play the dual role of developing urban sewage resources and significantly reducing pollution loads. In-depth treatment is also important for several large cities with water shortages involved in the eastern route of the South-to-North Water Diversion Project. These areas can take the lead in promoting advanced sewage treatment and recycled water utilization. The engineering and maintenance costs of secondary treatment of urban sewage are staggering. However, if on the basis of secondary treatment, in-depth treatment is carried out to turn the discharged treated water into recycled water and become an important part of a stable urban water source, then the huge cost of long-distance water transfer can be used for the regeneration of sewage and the development of sewage resources can be borne by the finance. This is a wise move that kills two birds with one stone and gets twice the result with half the effort. In short, advanced sewage treatment has no other options in areas surrounding closed and semi-enclosed waters and water-scarce areas. Even in water-rich areas such as the middle and lower reaches of the Yangtze River plains, it is also a good strategy to maintain a healthy water cycle. In the "Eleventh Five-Year Plan" of the Ministry of Construction, this key direction has also been clarified and specific indicator requirements have been put forward.: “When planning and building sewage treatment facilities in water-scarce cities, they must also arrange for the construction of reuse facilities and carry out in-depth treatment of sewage. For the construction of sewage treatment plants that discharge into closed water bodies, there should be requirements for phosphorus and nitrogen removal. In 2010, the urban sewage treatment rate in the three river basins (regions) of the Three Gorges Reservoir, Huaihe River, and Taihu Lake was not less than 80%, the urban sewage treatment rate in the five river basins (regions) of the Haihe River, Liaohe River, Chaohu Lake, Dianchi Lake, and Danjiangkou reservoir area and their upstream was not less than 70%, and the urban sewage treatment rate in the two river basins of the Yellow River and Songhua River was not less than 60%. The total amount of COD reduction shall not be less than 1.25 million tons, and the total amount of ammonia nitrogen reduction shall not be less than 150,000 tons. Fundamentally avoid the continued deterioration of urban water environment.” 3. Several current obstacles to the advanced treatment of urban sewage. Although in some areas of my country, advanced treatment of urban sewage has both objective necessity and subjective feasibility, it must be recognized that there are currently market obstacles and technical obstacles, which require the introduction of foreign aid for this work. 1. Market barriers Market barriers mainly refer to the fact that the current market cannot provide financial guarantee for advanced sewage treatment, which can be specifically broken down into price barriers and capital recovery barriers. The first is the price barrier. Water pricing and marketization in China * * different. The water price before the reform only included the price of water supply treatment, but did not include the price of water resources, nor the price of sewage treatment, nor the cost of the entire water ecology. Therefore, in terms of price, China is on the low side (the tap water price in Boston, USA is about US$5/ton, while the most expensive city in China, Beijing, is only US$0.45/ton). Not only is the price low, the sewage treatment fee collection mechanism is still imperfect. Most cities have a small sewage treatment fee collection area, low standards, and low collection rates. The sewage treatment fees collected cannot guarantee the normal operation of sewage treatment facilities. Secondly, there are obstacles to fund recovery, which mainly refers to * * Out of concern for people's livelihood, it is impossible to take coercive measures against people who are in arrears with their water bills, nor can it be achieved in one step during the water price reform. 2. Technical obstacles due to huge hazards and shortage of resources, coupled with * * According to the planning requirements, the above-mentioned key areas have an urgent need for advanced sewage treatment. However, efficient, reliable, and low-cost wastewater nitrogen and phosphorus removal technologies are still scarce in China, and many processes are only in the research or pilot stage. The overall solution to market and technical obstacles is to fully implement the franchise system in the urban water affairs field and encourage multiple entities to participate in the construction and operation of urban sewage advanced treatment facilities. In particular, large foreign water companies with both capital and technology should be introduced because they have the ability to cope with * * The pressure on capital recovery brought about by the gradual reform. 4. Prospects and main forms of advanced urban sewage treatment during the "Eleventh Five-Year Plan" period. Since the 1990s, especially since the mid-1990s, China's environmental protection industry, which mainly focuses on sewage treatment, has made great progress. The reason for this is that in addition to China’s continuous deepening of market-oriented reforms, there are also * * The implementation of environmental protection policies and policies has been greatly strengthened and opened to the outside world. Summarizing the current situation, it can be found that it is feasible to accelerate the industrialization of urban sewage advanced treatment during the "Eleventh Five-Year Plan" period in terms of capital, market and technology. The financial feasibility is based on two favorable factors. One is * * invest. It has been clarified in the "Eleventh Five-Year Plan" that "increase central and local financial investment, and use funds within the central budget and national debt funds to support the construction of sewage treatment facilities." According to estimates by Qiu Baoxing, Vice Minister of the Ministry of Construction, during the “Eleventh Five-Year Plan” period, all levels of * * Investment in sewage treatment will reach 330 billion yuan ； The second is the market-oriented reform of water prices. Water pricing and marketization in China * * different. China's water price reform was actually carried out on the basis that the water price system had not yet been formed. The original water supply was basically based on welfare water supply, that is, water price reform was carried out while marketization. Therefore, the trend of water price changes in China during the marketization process is exactly opposite to that in the United States, and will continue to increase. Because the original water price only included the price of water treatment, not the price of water resources, nor the price of sewage treatment, nor the cost of the entire water ecology. Therefore, as far as prices are concerned, China is raising prices while reforming. * * Both the State Environmental Protection Administration and the Ministry of Construction have made it clear that within 2007, all cities and towns in China will levy sewage treatment fees, and the sewage treatment fees in large and medium-sized cities will be raised to a level that maintains capital and makes a small profit. Market feasibility. In 2003, urban water supply, drainage, sewage treatment and reclaimed water reuse were listed as priorities in the public utility market reform by the State Council. This work is consistent with other developed * * The journey is different. Because in our country, these four industries were all controlled by state-owned enterprises in the past, and now market-oriented reforms must be carried out in three different stages. First, open the market, break the monopoly, and welcome foreign-funded enterprises and private enterprises to enter this industry. Now this stage has basically taken shape. ； Second, it is necessary to standardize the operating behavior of all enterprises, which means that the responsibilities and rights of all parties must be bound in the form of franchises and standardized contracts. ； Third, to represent the public interests and establish corresponding * * Supervision system to supervise water quality, water price, service quality, etc. China has now entered the second stage. Moreover, China follows the principles of the WTO in the water market and welcomes companies from all over the world to invest in China. Urban water services, including water supply, sewage treatment, and reclaimed water reuse, are now operated by many foreign-funded companies, such as France's Veolia and Suez. These giant water services groups have achieved very good operating results in China. Technical feasibility. The traditional A-0 method and AA-0 method have high operating costs. Considering the level of urban development and residents' income in my country, it is difficult to adopt such technologies on a large scale. The Ministry of Construction has made it clear that foreign companies are encouraged to participate in China's water market through technology shares or cooperation. The United States, the Netherlands, Germany, Japan and other countries have relatively mature low-cost nitrogen and phosphorus removal technologies that have been tested in long-term operation of sewage treatment plants. Through technical cooperation, it is possible to significantly reduce the cost of advanced urban sewage treatment and improve operational stability. In short, during the "11th Five-Year Plan" period, through market and technical cooperation with foreign companies, the prospects for advanced urban sewage treatment in some key areas in China are promising. (end)