Current situation and planning of sewage treatment

Current situation and planning of urban sewage treatment in China (I)

current situation and planning of urban sewage treatment in China (I)

July 22, 2004

the production history of urban sewage treatment equipment in China has been about 20 years. Its development can be divided into two stages:

1. 1980 ~ 1990 is the period of rapid development of urban sewage treatment equipment in China. In the early 1980s, the large municipal design institutes under the Ministry of construction began to develop and design urban sewage treatment plants and special equipment. In 1984, Tianjin Jizhuangzi sewage treatment plant, the first large-scale urban sewage treatment plant in China, was completed and put into operation. The completion of this sewage treatment plant created several national firsts at that time:

① it was the largest secondary urban sewage treatment plant in China at that time, with a treatment capacity of 260000 m3/d

② fast construction speed. It was designed by China Municipal Engineering North China design and Research Institute in 1982, constructed in 1983, and completed and put into operation in 1984. It took only more than two years from design to operation

③ all domestic equipment shall be used. More than 200 sets of more than 30 kinds of special equipment required by the whole plant are all designed by China Municipal Engineering North China design and Research Institute, and manufactured by more than a dozen manufacturers such as Tianjin municipal engineering machinery factory. The main equipment includes: grid trash remover, grit chamber scraper, dn=45m primary sedimentation tank scraper, dn=45m secondary sedimentation tank suction machine, dn=1.2m screw pump, dn=18m thickener, vacuum drum dehydrator, blower, biogas generator, etc. At present, except for some equipment updates, most of the equipment is still running

the successful operation of Tianjin Jizhuangzi sewage treatment plant has made China's urban sewage treatment begin to move towards the road of large-scale and industrialization, and laid the original foundation for the design and manufacture of special equipment for urban sewage treatment in China. Subsequently, Hangzhou Sibao Sewage Treatment Plant (with a treatment capacity of 400000 m3/D, primary treatment), Guangzhou Datansha sewage treatment plant (with a treatment capacity of 150000 m3/D, secondary treatment,

a2/o process) and Wuxi Lucun sewage treatment plant (with a treatment capacity of 200000 M3/D, secondary treatment) were successively completed. Most of these sewage treatment plants also use domestic equipment. China's sewage treatment industry has thus entered a real period of development in the field of expanding utilization. Some equipment manufacturing industries, such as Tangshan Qingyuan, Yangzhou Tianyu, Yixing first ring road, Tianjin municipal engineering machinery plant, etc., have developed during this period

2 after 1990, it was mainly to use foreign government loans to purchase foreign equipment to build urban sewage treatment plants. Since 1988, due to the lack of funds for the construction of sewage treatment plants in China, developed countries in Europe have successively provided government loans, most of which can only be used to purchase the technology and equipment of the lending countries. It should be recognized that foreign government loans with favorable conditions have injected vitality into China's sewage treatment industry, greatly improved the sewage treatment technology and automation, and promoted the construction of modern sewage treatment plants in China. However, the resulting negative effects are also great. First, the capital construction investment of sewage treatment plants has been increased. The price of foreign equipment is generally 3 ~ 4 times higher than that of domestic equipment, and some are 7 ~ 8 times higher; Second, because more than 90% of the newly-built sewage treatment plants use loans to introduce equipment, China's sewage treatment equipment manufacturing industry has been seriously restrained. State owned large and medium-sized enterprises rarely intervene in this field, and most of them are township and small and medium-sized enterprises. These enterprises have small production scale, low technical level and weak development ability, which aggravates the gap between China's urban sewage treatment equipment and foreign similar products

in the past two years, in order to speed up the construction of urban sewage treatment plants in China and accelerate the localization of complete sets of equipment for urban sewage treatment plants, the State Economic and Trade Commission has given financial support to determine some key equipment technology development projects for urban sewage treatment, which will be subject to public bidding in China and will be completed within two years. Twelve large enterprises won the bid and completed the task on schedule. However, the work of equipment localization has not been promoted quickly, which can be said to have little effect. The reason is that the construction of urban sewage treatment plants is still carried out by means of foreign government loans to purchase foreign equipment. To change this situation, the state should formulate some relevant policies to support the localization of equipment. Sewage treatment equipment quality status

in 1998, the quality supervision and inspection center of environmental protection machinery products in the machinery industry, entrusted by the State Bureau of technical supervision, conducted supervision and random inspection on the quality of water treatment equipment. The main problems are: (1) materials are not used according to standards; (2) Backward production mode; (3) Poor welding and paint quality and corrosion resistance; (4) The qualification rate of purchased parts and outsourced parts is low; (5) The test means are not perfect; (6)

the quality assurance system is not perfect

the main differences between the sewage treatment equipment produced in China and similar foreign products are: (1) the quality of raw materials is unstable; (2) Backward process level; (3) Low degree of automation and many control system failures; (4) The testing equipment is not matched; (5) Poor reliability and low service life. Equipment standard status

since the 1980s, the North China design and Research Institute of municipal engineering, the centralized unit of water treatment equipment and equipment standards of the Ministry of construction, has begun to organize the formulation of standards for water treatment equipment and equipment under the leadership of the standard quota Department of the Ministry of construction, and has formulated 110 industry standards so far. Relevant industry standards have been formulated for major urban sewage treatment equipment, such as: grid trash remover, travelling sand scraper, radial flow sedimentation tank sludge scraper, thickener, belt filter press, suspended central drive sludge scraper, screw pump, rotary brush aerator, microporous aerator, etc. The formulation of these standards has played a role in promoting the development of China's water treatment industry. The technical requirements in these standards are not low compared with the standards of similar foreign products, and some are even slightly higher than the standards of foreign advanced manufacturers. For example, the model and technical requirements of sludge scraper and suction in radial flow sedimentation tank are equivalent to German DIN standards, and the test methods and requirements of belt filter press are equivalent. Non industry capital is also eager to try Japanese JIS standards. However, due to the influence of imported equipment in recent decades, the equipment drawings and data provided by the United States, Britain, France and other countries are still in English system, without legal units of measurement, which makes the specifications of imported equipment very confused. In order to supplement the shortage of imported equipment, domestic equipment supporting facilities are also required to be produced according to the specifications of imported equipment, so that the industry standards formulated by our country cannot be implemented, forming a situation of "failure to comply with laws and orders"

in addition to the industrial standards for urban treatment equipment formulated by the Ministry of construction, the Ministry of machinery, the Ministry of chemical industry, the National Environmental Protection Agency and other departments have also formulated relevant industrial standards. In order to make you have a comprehensive understanding of the standards of water treatment equipment in China, the catalogue of main equipment standards formulated by major departments in China is summarized (see Table 1 for details) for the reference of equipment manufacturers and design units

as can be seen from table 1:

(1) various departments in China have formulated relevant standards for commonly used sewage treatment equipment, which used to be called "special equipment", and now has developed towards standardization and serialization

(2) there is a serious repetition in the standard, such as "belt filter press", and the Ministry of construction and the former Ministry of machinery have formulated relevant standards; The Ministry of construction, the former Ministry of machinery and the Ministry of chemical industry have also formulated relevant standards for "radial flow sedimentation tank sludge scraper". This makes the same products inconsistent in specification, model and name, and brings difficulties to users in selection and bidding and tendering of engineering construction

Table 1 standard catalogue of common urban sewage treatment equipment

serial number standard number standard name

1cj/t39-1999 plane grille

2cj/t80-1999 belt filter press for sludge dewatering

3cj/t81-1999 mechanical stirring clarifier mixer

4cj/t82-1999 mechanical stirring clarifier scraper

5cj/t3007-1992 water supply Screw pump for drainage

6cj/t3014-1993 gravity sludge thickener suspension center drive sludge scraper

7cj/t3015.1-1993 microporous aerator for sewage treatment through computer high-speed sampling

8cj/t3015.2-1993 aerator clean water oxygenation performance measurement

9cj/t3015.4-1996 sewage treatment can be tensioned Microporous aerator

10cj/t3029-1994 adjustable weir plate (300 ~ 500mm)

11cj/t3042-1995 radial flow sedimentation tank peripheral drive sludge scraper for sewage treatment

12cj/t3043-1995 gravity sludge thickener peripheral drive sludge scraper

13cj/t3044-1995 grit chamber traveling type sludge scraper for sewage treatment

14cj/t3048-1995 plane grid trash remover

15cj/t3061-1996 dissolving agent mixing equipment for water treatment

16cj/t3065-1997 arc grid trash remover sewage machine

17cj/t3071 － 1998 rotary brush aerator

do not immediately cover the dust cover 18gb9067-1998 belt press filter model and basic parameters

19gb10899-1989 belt press filter technical conditions

20gb10900-1989 belt press filter test method

21gb10894-1989 determination of sound power level of separation machinery noise -- engineering method

22gb10896-1989 plate and frame filter press and box filter press test method

23jb2932-1986 water treatment equipment manufacturing technology Conditions

24jb4266-1986 arc screen

25jb/tq685-1988 belt press filter product quality classification

26jb/tq689-1988 separation machinery product sampling and grade evaluation method

27jb/t502-1991 spiral discharge sedimentation centrifuge model and basic parameters

28jb/t4335-1991 spiral discharge sedimentation centrifuge model technical conditions

29jb/t6418-1992 separation machinery cleanliness determination method

30jb/t7217-1994 General technical conditions of separation machinery coating

31jb/t53220-1994 plate and frame filter press product quality classification

32jb/t5152-1991 box filter press and plate and frame filter press model and basic parameters

33jb/t4333-1997 technical conditions of box filter press and plate and frame filter press

34jb/t6932-1993 biological contact oxidation domestic sewage purifier

35jb/t7257-1994 traveling crane type plate lifting, scraping, scraping and sanding machine

34jb/t6932-1993

36jb/t5283-1 997 non metallic filter plate and frame

37jb/t8696-1998 radial flow secondary sedimentation tank peripheral drive suction dredger

38jb/t8700-1998 oxidation ditch horizontal shaft rotary brush aerator technical conditions

39hg21548-1993 radial flow secondary sedimentation tank suction dredger standard series

40hj/t11-1996 classification and naming of environmental protection equipment

41hcrj023-1998 mechanical surface aerator

42hcrj026-1998 hydrocyclone purifier

43hcrj028 － 1998 rotation Type fine grid

44hcrj031-1998 microporous aerator

45hcrj033-1998 submersible sewage pump

46hcrj034-1998 aeration rotary brush

47hcrj050-1999 rotary disk aerator

48hcrj054-1999 box filter press and plate frame filter press

49hcrj055-1999 mud suction machine

50hcrj056-1999 mud scraper

51hcrj009-1999 grid trash remover

in recent years, China's urban sewage treatment industry has developed rapidly, Sewage treatment equipment manufacturing industry is also one of the industries with rapid development. The strength and investment of the state in environmental protection management have increased year by year. In order to meet the needs of this form of development, the sewage treatment equipment manufacturing industry must be rectified and put forward higher requirements. In order to improve product quality and narrow the gap with similar foreign products, first of all, a unified national standard should be formulated for water treatment equipment, and there should be unified specifications for the specifications, models, technical requirements, test methods, inspection and acceptance of various equipment. It is suggested that the country