The development process and background of industrial wastewater treatment

1. Development history and background of industrial sewage treatment

1.1 Development of foreign industrial sewage treatment The development of foreign sewage treatment industry started earlier than China, in 1914, the United Kingdom created the activated sludge process, applied to the sewage treatment process and achieved a certain degree of effect. Compared with European countries, our country is short of water resources per capita. In general, the water resources of Europe and the United States and other countries are relatively healthy, but the pollution caused by industrial sewage is a global problem, and the sewage treatment problem is the development of every country can not get rid of. As early as the 1990s, the European Community put forward requirements on water quality. Industrial and agricultural sewage flowing into water bodies caused the eutrophication of seawater lakes, which threatened the survival of water organisms, and the quality of underground drinking water was also affected. In 1975, the European Union enacted the law on surface water requirements, and in 1980, the law on drinking water requirements was enacted to regulate the water quality of groundwater, fishery and aquaculture water. In different countries and regions, the environmental background is different, the degree of water resources affected by sewage is different, and the development, requirements and process technology of sewage treatment are different. In some countries with rich water resources, sewage treatment regulations and facilities are simplified. For some industrially developed areas, water resources are regarded as wealth like crude oil, and the development and development of sewage treatment is relatively mature.

1.2 Development history and background of industrial sewage treatment in China

1.2.1 From 1920 to 1949, the construction of sewage treatment plants began one after another. In 1923, China's first urban sewage treatment plant was built in the northern district of Shanghai, and in the following years, urban sewage treatment plants in the western and eastern regions of Shanghai came out. Before this, industrial sewage, urban sewage and rainwater in various regions were directly diverted into rivers and lakes or the sea by ditches or pipes, and sewage was treated solely by drainage.

1.2.2 During the decade from 1950 to 1960, the main tasks were to organize and standardize the old pipes laid by direct sewage in the old city of Shanghai, remove unreasonable sewage pipes, strictly control the pollution of rivers and lakes in the area, and invest in the construction of a part of first-level sewage treatment plants after the completion of the transformation of standardized new sewage pipes. In Beijing, Shanghai and other places began to form a first-level sewage treatment plant with a daily treatment capacity of more than 100,000 tons.

1.2.3 From 1961 to 1978, land irrigation was applied to sewage treatment. In 1957, the relevant departments included this technical achievement in the national scientific research plan, and in the following years, multinational technical exchange meetings were held to actively develop and summarize the training and implementation of new technologies. At this stage, China invested in the construction of a large number of biological oxidation ponds; After the trial construction in many areas of China, the national sewage treatment capacity has been increased to one million tons per day, and the new sewage treatment pipeline has reached 19600km.

1.2.4 During this period from 1979 to 2000, China's sewage treatment officially entered the modern development in line with international standards, and the development speed was improved qualitatively. In the early 1980s, two production sewage treatment experimental bases were built successively in Tianjin and Beijing, and a large number of development and technical personnel joined together to conduct large-scale exploration experiments and research on sewage treatment technology and development routes in the two regions. The secondary biological treatment technology is deeply applied in the wastewater treatment process. After several years of continuous exploration, Tianjin built the largest sewage treatment plant in China in 1984, adding the new standard activated sludge biochemical process, and achieved remarkable results in local environmental improvement during a period of operation and production, and the treatment capacity was stable. Sewage treatment in our country has become large-scale and enterprise-oriented.

1.2.5 From 2001 to 2015, China in the 21st century is the world's China. With the reform and opening up, China's economic development has entered a stage of acceleration, and the development of sewage treatment industry is also a good momentum. As the country attaches more and more importance to environmental governance and puts forward the strategic goal of sustainable development, and constantly refining the requirements for sewage treatment, In the country, almost every industrial park has its own sewage treatment plant, urban sewage treatment plants are also entering the high-standard version of large-scale investment and construction, the development of sewage treatment industry benefited from the introduction of environmental protection laws and regulations to improve the continuous attention to environmental protection, environmental protection legislation.