Keywords: environmental engineering; Sewage treatment; Current situation; question
introduce
The development of the city and the operation of all links are inseparable from the application of water resources. Without reliable and safe water resources as a guarantee, urban development and progress will only be an empty slogan. Doing a good job in urban sewage treatment is the key link to make full use of urban water resources reasonably, and it is also an important factor for citizens to live more comfortably and safely.
1 Present Situation of Urban Sewage Treatment in China and Environmental Engineering
At present, the sewage treatment rate in China is not very high. In the past, sewage treatment was only a single stage of pollution source control and pollutant concentration reaching the standard. At present, it is the stage of comprehensive control of scribing pollution and total emission control of pollutants based on environmental capacity. At present, urban sewage treatment plants have the characteristics of large area, long service life, large equipment scale, stable operation effect and large capital investment [1]. According to the actual situation of the target city, China can learn from foreign excellent sewage treatment experience and emerging technologies, and selectively choose schemes and technologies to reduce sewage treatment costs and facilitate operation and maintenance. At present, the main sewage treatment technologies in China are SBR, A20 (anaerobic aerobic treatment) and MBR (membrane separation technology).
2 problems in urban sewage treatment in China's environmental engineering
Although the urban sewage treatment in China has developed rapidly, there are still many problems, mainly as follows: First, the infrastructure is not perfect. In the aspect of sewage treatment, many cities only pay attention to the construction scale of sewage treatment plants and the main road of drainage pipe network, but not to the construction of mobile phone branch pipes and household branch pipes, which leads to the low matching efficiency of sewage collection pipe network and makes its function unable to be effectively played or even utilized. Second, the management and maintenance work is not done enough. In the practical work of urban sewage treatment, the post-maintenance of pipe network is not enough. The pipe network in suburbs or remote places far away from urban areas is often damaged and left unattended. For example, the construction of municipal facilities causes damage to the pipe network and cannot be repaired in time. Third, the sewage treatment capacity needs to be improved. Judging from the annual discharge of urban sewage, the annual treatment capacity of urban sewage in China needs to be improved. According to relevant data, the urban sewage discharge in China increases by about 2.4 billion m3 every year, but the sewage treatment capacity only increases by 300 million m3 every year. It can be seen from the data that there is a serious imbalance between the annual sewage discharge and the sewage treatment capacity [2]. In addition, compared with foreign sewage treatment capacity, China's urban sewage treatment capacity needs to be improved. The fourth is the problem of sewage treatment funds. The construction and operation of sewage treatment facilities need huge financial support. The investment in sewage treatment per cubic meter of perfect sewage treatment facilities is generally1500 ~ 2,000 yuan, and the recurrent cost is about 0.4 yuan /m3[3]. For a long time, the funds for the construction of urban sewage treatment facilities in China have come from the state. The construction of sewage treatment facilities should precede the urban infrastructure, but with the continuous expansion of the city scale, the unilateral funding sources of the state can no longer meet the needs of urban infrastructure construction, resulting in a serious lag in the construction of urban sewage treatment facilities. Fifth, the operating efficiency of sewage treatment enterprises is generally low. For a long time, the operation of urban sewage treatment facilities in China has been monopolized by the government. Due to the asymmetry of information base, operating institutions lack effective development restraint mechanism, competition mechanism and internal cost supervision mechanism. The lack of these mechanisms leads to the profit source of operating institutions is cost inflation, which in turn leads to huge efficiency loss in operation. Sewage treatment institutions can not reduce operating costs, making operating institutions redundant.
3 China urban sewage treatment environmental engineering solutions
With the continuous advancement of urbanization in China, the pollution sources of water resources have become more complicated. Therefore, it is of great significance to improve the construction of urban sewage treatment facilities and carry out a series of related research. The following puts forward some corresponding countermeasures for the existing problems.
3. 1 Improve the supporting construction of the corresponding sewage collection pipe network.
1) Carry out regional treatment on the supporting pipe network, find out the main sources and ways of urban sewage, and carry out planned transformation on the diversion system. 2) Investigate the existing and operating facilities in advance to solve their problems.
3.2 Improve the construction of pipe network maintenance system
Urban sewage treatment should improve the maintenance and management system, regularly inspect remote areas or suburbs of the city, and take corresponding emergency measures for the construction near sewage treatment pipelines.
3.3 Improve sewage treatment capacity
To improve the sewage treatment capacity, we must first improve the sewage regeneration efficiency, and then choose advanced sewage treatment technology. Improving the efficiency of sewage reuse not only saves water resources, but also promotes the development of the cause through sewage reuse. Sewage treatment technology directly affects sewage treatment capacity and efficiency. Sewage treatment technology should first adopt clean production technology with high resource utilization rate, less pollution and favorable comprehensive utilization. At present, the urban pollution treatment process in China is mainly activated sludge pollution control method, which has low energy consumption and running cost and can effectively reduce the organic load [4].
3.4 Solve the problem of insufficient funds
We should improve the original financing mode, adopt effective methods, apply advanced operation mode, change the financing mode dominated by government funds, expand financing channels, and make urban sewage treatment market-oriented financing. In addition, we can apply TOT mode, bot mode and managed operation mode [5] to operate.
4 conclusion
Modern urban sewage treatment can improve the utilization rate of water resources, maintain the long-term stable development of urban economy and provide safe water resources guarantee for the urbanization process. Considering the national conditions, the level and concept of urban development in China are insufficient [6], so that the importance of urban sewage treatment for urban construction will be ignored, which is very unfavorable to the development of urban economy. It is of great significance to understand the present situation of urban sewage treatment in environmental engineering in China and analyze its existing problems.
refer to
[1] Guo Chunli. Study on theory and model of comprehensive benefit evaluation of urban sewage treatment projects [D]. Xiangtan: Hunan University of Science and Technology, 2009.
[2] Song Pei Di. Study on the management method of organizing and implementing urban sewage treatment projects [D]. Nanjing: Hohai University, 2006.
[3] Xiao fen. On the importance of urban sewage treatment in environmental protection projects [J]. Manager, 20 16(2 1):335.
Hou, Hou, Li. Discussion on urban sewage treatment in environmental engineering [J]. Low carbon world, 2016 (29):15-16.
[5] learning. Discussion on project management mode of urban sewage treatment facilities [D]. Chengdu: Sichuan University, 2003.
Xu Qian. On the significance of urban sewage treatment in environmental protection projects [J]. Resource conservation and environmental protection, 20 15(9):7 1.
For more information about project/service/procurement bidding, and to improve the winning rate, please click on the bottom of official website Customer Service for free consultation:/#/? source=bdzd