China's sewage treatment industry technology development and innovation capabilities
With the rapid development of China's economy, the traditional extensive and labor-intensive economic development model has brought about a series of environmental problems. Among them, the problem of water pollution is particularly serious.
At present, water pollution has become a major problem that restricts economic development, affects social stability, endangers human health, and destroys ecological balance. At the same time, China's natural water resources are extremely limited. Therefore, the development and innovation capabilities of sewage treatment and wastewater resource technology should be further emphasized.
Current status of water resources in China
China is a country with poor water resources. The total water resources is about 2.8×1012m3, ranking sixth in the world. The per capita water resources are 2310.4m3, ranking 110th in the world, only one-fifth of the US, Canada. 1/50, therefore, China is listed as one of the 13 poor countries in the world. The data released by the National Bureau of Statistics shows that in recent years, China's per capita water consumption has increased year by year, from 412.9m3 in 2003 to 450.2m3 in 2010. The water conservancy department predicts that by 2030, China's population will reach 1.6 billion, and the per capita water resources will be reduced to 1760m3, reaching the world-recognized water shortage warning line. The total water shortage will reach 4.0×1010～5.0×1010m3. China's water resources distribution is uneven, and more than 80% of the total water resources are concentrated in the Yangtze River and its south. In terms of per capita water resources, the highest region in the south and the lowest region in the north are tens of times different, and the west is even 500 to 600 times higher than the east. According to statistics, among the 669 cities in China, 400 cities have insufficient water supply all the year round. Among them, 110 cities are seriously deficient in water, and the annual water shortage is 6.0×109m3. The annual economic loss caused by water shortage is more than 200 billion yuan.
China's current sewage situation
According to the "2010 China Environmental Status Bulletin" and the 2010 National Bureau of Statistics data, during the "Eleventh Five-Year Plan" period, China's wastewater discharge increased by an average of 4% year by year; among them, the total national wastewater discharge in 2010 was 61.73 billion. Tons, chemical oxygen demand emissions were 12.281 million tons, ammonia nitrogen emissions were 1.203 million tons; the seven major water systems were generally lightly polluted, and 204 rivers were 409 surface water national control monitoring sections, I~III, IV~ The proportions of the water quality of Class V and Class V are 59.9%, 23.7% and 16.4% respectively; the lake water pollution is serious, and among the 26 key lakes (reservoirs), the II~III water only accounts for 23%, and the IV class accounts for only 23%. 15.4%, V class accounted for 23.1%, poor V class accounted for 38.5%; national groundwater quality status is not optimistic, water quality is excellent - good - good level of monitoring points totaled 1759, accounting for 42.8% of all monitoring points, 2351 The water quality of the monitoring points is poor-very poor, accounting for 57.2% of all monitoring points.
China's sewage treatment industry technology development status
As early as 1921, China's first sewage treatment plant, the Shanghai North District Wastewater Treatment Plant, was completed and put into operation, but large-scale sewage treatment started late in China. From the early days of liberation to the end of the 1960s, China mainly promoted sewage irrigation. There were only 10 sewage treatment plants in the country (including three built before liberation). In the 1970s, the scale of sewage treatment began to expand. By 1978, 37 urban sewage treatment plants had been built nationwide with a treatment capacity of 635,300 tons/d. Since the reform and opening up, the development of urban sewage treatment technology in China has been roughly divided into three stages:
The first stage: from the late 1970s to the end of the 1980s. China began to enter the period of economic construction as the center, and environmental problems such as sewage were more prominent. The Ministry of Construction included the urban sewage reuse project in the “Sixth Five-Year Plan” special science and technology plan and began research work on urban wastewater reuse. Subsequently, in view of the water shortage problem that some cities in the north need to solve in the economic development, China carried out major scientific and technological research projects on “Urban Wastewater Resources Research” during the “Seventh Five-Year Plan” period, and obtained a series of important sewage treatment and utilization. Technical achievements. In 1984, the largest sewage treatment plant in China, Tianjin Jizhuangzi Wastewater Treatment Plant was completed and put into operation, filling the gap in the construction of large-scale sewage treatment facilities in China. By 1988, 78 sewage treatment plants had been built nationwide. At that time, the technology and funds needed for construction in this area mainly depended on the domestic market, and the development speed was subject to many conditions.
The second stage: from the late 1980s to the end of the 1990s. During the "Eighth Five-Year Plan" period, China completed a major scientific and technological research project "Urban Sewage Resource Research", researched and developed a complete set of sewage treatment technologies suitable for some cities, solved water quality indicators and reuse routes, and established a series of Demonstration project. In 1996, the State Science and Technology Commission and the Ministry of Construction carried out the “National Key Scientific and Technological Research Project of the Ninth Five-Year Plan”, “Study on Key Technologies of Wastewater Treatment and Water Industry”, aiming to solve major key problems in water pollution prevention and control. With the continuous deepening of reform and opening up, some advanced and efficient sewage treatment equipments have entered the market of China's sewage treatment industry. Due to the source of funds and the nature of the operation and management of the sewage treatment industry, the speed of sewage treatment is still not satisfactory. By the end of the 1990s, the number of secondary sewage treatment plants nationwide had increased to 200, concentrated in large and medium cities.
The third stage: 2000 to the present. Since the 21st century, China's sewage treatment industry has entered a stage of rapid development. During the "10th Five-Year Plan" period, the state began to take environmental protection as an important means of macroeconomic regulation and control, adopted a series of major policy measures, eliminated a number of backward production capacity with high consumption and high pollution, and achieved good results. In 2006, the central government proposed (now implemented) the National Medium- and Long-Term Plan for Science and Technology Development (2006-2020), which included 16 water pollution control and treatment and large-scale aircraft, manned spaceflight and lunar exploration projects for the first time. Major scientific and technological projects, this measure has effectively promoted the development of sewage treatment technology. During the “Eleventh Five-Year Plan” period: the national urban sewage treatment capacity reached 100 million tons/day, the urban sewage treatment rate increased from 52% in 2005 to 72%; the chemical oxygen demand decreased by 12.45%, exceeding the target; the national surface water country The proportion of controlled section water quality superior to Class III increased to 51.9%. For the first time in the “Twelfth Five-Year Plan” of national environmental protection, ammonia nitrogen emissions are used as emission reduction targets. It is proposed that the daily sewage treatment capacity will be 42 million tons by 2015, basically achieving sewage treatment capacity in all counties and key towns; sewage treatment facilities. The load rate has increased to over 80%, and the urban sewage treatment rate has reached 85%; the urban sewage treatment plants in Dianchi, Chaohu, Taihu and other key urban areas and coastal areas must increase the level of nitrogen and phosphorus removal.