History of sewage treatment and environmental protection

The successful experience of design, construction and management of Tianjin Jizhuangzi sewage treatment plant has played a demonstration role in the construction of large-scale urban comprehensive sewage treatment plant in China, and has also laid the foundation for the large-scale development of sewage treatment industry in China in the 1980s.

(3) The development of sewage treatment technology and the achievements of sewage treatment plant construction at the end of the 20th century

The establishment of the national "Seventh Five-Year Plan", "Eighth Five-Year Plan" and "Ninth Five-Year Plan" scientific and technological research topics has made gratifying scientific research achievements in China's new technology of sewage treatment, new technology of sludge treatment and new technology of recycled water reuse, and some projects have reached the highest level.  Foreign sewage treatment technology, new technology, new equipment has been introduced into China, in the activated sludge process application at the same time, AB method, A/O method, A/A/O method, CASS method, SBR method, oxidation ditch method, stabilization pond method, land treatment method, etc., also in the construction of sewage treatment plants have been applied. From the past sewage treatment technology that only has the function of removing organic matter to the development of multi-functional process technology with phosphorus and nitrogen removal, some of the most advanced and foreign sewage treatment equipment has entered the market of China's sewage treatment industry. Such as grid machine, submersible pump, sand removal device, mud scraper, aerator, blower, sludge pump, dehydrator, biogas generator, biogas boiler, sludge digestion and mixing system and other large equipment.

Due to the large investment in the construction of large-scale urban sewage treatment plants, China's construction funds are limited, and can not meet the needs of water pollution control. Therefore, the introduction of foreign funds to construct sewage treatment plants has become an important part of the construction funds, which also speeds up the construction speed of China's urban sewage treatment plants. A number of large-scale urban sewage treatment plants have been built and put into operation by using foreign loan projects. For example, Beijing Gaobeidian sewage plant, the largest sewage treatment plant in the 20th century in China, has a treatment scale of 500,000 m3/d in the first phase and up to 1 million m3/d in the second phase. The treatment scale of Hangzhou Sibao sewage Treatment plant is 600,000 m3/d; The treatment scale of Tianjin Dongjiao sewage treatment plant, Chengdu Sanwa Kiln sewage treatment plant, Shenyang Northern sewage treatment plant and Zhengzhou Wangxinzhuang sewage treatment plant is 400,000 m3/d. The construction of these large sewage treatment plants marks the growing of our sewage treatment business, the development of sewage treatment technology in our country, the importance of our government to sewage treatment business, and also indicates that our sewage treatment business has developed to a new stage.

The present situation and prospect of the development of urban sewage treatment in China

(1) The shortage of funds for the construction of sewage treatment plants

Although more than 100 sewage treatment plants have been built in China, they are still far from meeting the needs of urban industrial and agricultural production and people's lives, manifested in the treatment rate of a city itself is not high, that is, the amount of sewage treatment is not enough, and manifested in large cities have begun to carry out the planning and construction of sewage treatment plant construction. However, in small and medium-sized cities, especially in the northwest, the planning and construction of sewage treatment have not been included in the urban development agenda. One of the main reasons is that there is no special construction funds, and water pollution in some areas is becoming increasingly serious. If we wait for the investment of funds to build sewage treatment plants, the environment will tend to deteriorate, which will bring inconvenience to people's lives and harm people's physical and mental health. Therefore, we need to raise funds in various ways to speed up the treatment of water environmental pollution. To leave a beautiful living environment for future generations.

(2) The operation funds of the sewage treatment plant cannot be in place

At present, more than 100 sewage treatment plants have been built and put into operation nationwide, and less than one-third of them can operate at full capacity. Reasons for not running at full capacity: Most of them are caused by the operation of funds can not be in place, some provinces and cities do not collect sewage treatment fees, some only collect factories, enterprises, do not collect residents, some factories, enterprises, residents have been collected, but the fee standard is set very low, far from meeting the minimum cost required for the normal operation of sewage treatment plants. This has given rise to the practical problem of some sewage treatment plants treating as many tons of sewage as are available for funding. Such a long time can not play the construction of sewage treatment plant due benefits, will also make the instrument, equipment damage, but also can not play the role of professional management of sewage treatment plant.