The lack of the hottest sewage treatment capacity

Insufficient sewage treatment capacity has become a bottleneck in urban development. How to make up for the shortcomings of facilities. Release date: Source: Science and technology

in order to win the battle of pollution prevention and control, the implementation plan for the strengths and weaknesses of urban domestic sewage treatment facilities was recently issued, requiring that by 2023, the facility capacity of cities at or above the county level basically meet the needs of domestic sewage treatment

according to the statistics of the Ministry of housing and urban rural development, the sewage treatment capacity of cities and counties in China exceeded 210million cubic meters/day in 2019, and the length of sewage pipes reached 570000 kilometers. Nevertheless, the short plate of sewage collection pipe in China is relatively prominent, and the "capillary" is missing, and the problems of old pipe damage and mixed connection and wrong connection are widespread; The phenomenon of "heavy water light mud" is relatively common, the construction of sludge treatment and disposal facilities lags behind, and the harmless and resource-based disposal is not standardized, and the level is generally not high

in order to make up for the weaknesses of facility construction and win the battle of pollution prevention and control, the national development and Reform Commission and the Ministry of housing and urban rural development recently jointly issued the implementation plan for making up the weaknesses of urban domestic sewage treatment facilities (hereinafter referred to as the implementation plan), which requires that by 2023, the facility capacity of county-level and above cities will basically meet the needs of domestic sewage treatment; The harmless disposal rate and resource utilization rate of urban sludge were further improved, and the resource utilization level of sewage in water shortage areas and water environment sensitive areas was significantly improved

the sewage treatment capacity is insufficient, and the development bottleneck of Chengcheng City

according to the national surface water quality situation in the first half of 2020 reported by the Ministry of ecological environment, among the 1940 national surface water assessment sections, the proportion of sections with good water quality is 80.1%, an increase of 5.6 percentage points year-on-year; The proportion of sections inferior to class V was 1.1%, a year-on-year decrease of 3.2 percentage points. Compared with the significant improvement of water environment quality, urban domestic sewage treatment capacity has become a prominent weakness in comprehensively promoting water pollution prevention and control

Liu Bo, Secretary General of Changsha sponge city ecological industry technology innovation strategic alliance in Hunan Province, told Science and technology that the two departments issued the implementation plan because the capacity of sewage treatment facilities in domestic cities above the county level has been insufficient for a long time, which has become the bottleneck of urban development, and the urban water ecological environment urgently needs to be improved. "During the 12th Five Year Plan period, a large number of sewage treatment facilities have been built to solve the problem of insufficient sewage treatment capacity in some cities. However, due to the lack of matching pipes, wrong and mixed pipes, mixed flow of rain and sewage and low pollution load of influent water, many cities have not achieved the ideal treatment effect, and pollution caused by sewage overflow is widespread."

"Although on the whole, the sewage treatment rate indicators of cities and counties across the country are high, many central and western cities and towns have problems such as incomplete coverage and uneven layout of sewage treatment facilities. Due to the rapid growth of urban area and population, the layout and construction of sewage treatment facilities in some areas are difficult to match the local sewage discharge in time. And some poverty alleviation and relocation areas, due to the lack of sufficient funds, many sewage treatment facilities Not yet matched. " Zhuliyang, director of the resources and environment business department of China International Engineering Consulting Co., Ltd., said that the conditions of mismatched pipes, leakage and poor operation and maintenance have brought problems such as the quality of influent water from the sewage treatment plant, the unstable amount of detailed research on the material detection of water kaiqiangli experimental machine, and the low treatment efficiency of the sewage treatment plant. With the increasingly stringent national discharge standards, the cost of sewage treatment continues to rise

carry out the strengths and weaknesses of urban domestic sewage treatment, and build systematic projects covering sewage collection pipes, sewage treatment plants, sludge treatment and disposal and sewage recycling, which can not only form current investment, but also attract industrial investment and drive the development of green industries. The relevant person in charge of the national development and Reform Commission said that this is of positive significance to promote the formation of a strong domestic market and promote economic and social development. The implementation of the implementation plan can also promote the continuous improvement of water environment quality, meet the people's growing health needs and beautiful ecological environment needs, and enhance the people's sense of happiness, gain and security

encourage biomass utilization methods to find a way out for sludge

in view of the main weaknesses of urban domestic sewage treatment facilities, the implementation plan puts forward four main tasks: strengthening the weaknesses of urban sewage treatment plants, supplementing the weaknesses of urban sewage collection pipes, accelerating the harmless disposal and resource utilization of sludge, and promoting the construction of information systems

the relevant person in charge of the national development and Reform Commission said that management is the top priority to make up for weaknesses, including accelerating the elimination of urban villages, old urban areas, urban-rural fringe management blank areas, and accelerating the completion of the "capillaries" of the pipe; Except in arid areas, rain and sewage diversion shall be strictly enforced for new pipelines; Cities in the Yangtze River Basin and its south should promote the transformation of rainwater and sewage confluence pipes and reduce the frequency of overflow pollution

Liu Bo believes that according to the implementation plan, to truly separate rainwater and sewage, it is also necessary to build a sponge city according to the principle of decentralized treatment at the source, so as to realize rainwater storage, purification and utilization. The purified rainwater can be priced with reference to the price of tap water, and rainwater can be widely used for toilet flushing, garden greening, etc., so as to completely reduce the pressure of sewage pipe transmission and treatment. At the same time, gradually implement the rainwater discharge and treatment charging system, separate the rainwater and sewage treatment fees, and use them respectively for the construction of rainwater and sewage collection and treatment capacity, and control the non-point source pollution of rainwater runoff and sewage overflow pollution from the source, so as to eliminate the largest pollution source of urban water environment

as a product of sewage treatment, sludge can be said to be the "last mile" of sewage treatment. According to the data released by E20 water industry research center, the production of urban wet sludge in China was 46.46 million tons in 2018 and will rise to 52.92 million tons in 2020

promoting the harmless and resource-based treatment and disposal of sludge is considered to be the difficulty of reinforcing the strengths and weaknesses. Hang Shijun, former deputy chief engineer of Beijing Municipal Engineering Design and Research Institute, said that at present, one of the key problems in realizing the harmless treatment and disposal of sludge in China is to systematically solve the outlet problem of sludge, so that sludge treatment and disposal can become a link in the ecological cycle industrial chain of urban waste, and form a sustainable sludge utilization and consumption mode

the implementation plan encourages large and medium-sized spring tension testing machines in short supply of land resources to adopt the disposal mode of "biomass utilization to produce biodegradable shopping bags, lunch boxes and other products + incineration". Biogas produced by biomass utilization can be used for power generation and heat generation, and incineration is the key process route to solve the sludge problem. At present, the way out for sludge accumulation and disposal is limited. Some cities with conditions can use kilns for collaborative incineration, and the incineration ash can be used as building materials or for phosphorus recovery

guide the participation of social capital to achieve the goal of water ecological restoration

in order to ensure the implementation of the implementation plan, the national development and Reform Commission requires to strengthen organization and coordination, with cities and counties as the first person, speed up project planning and reserves, and clarify the construction sequence; All localities should bring the land for sewage treatment facilities into the scope of urban yellow line protection, and reasonably reserve land space; Strengthen the collection of sewage treatment fees, and promote the determination of sewage treatment service fees through market-oriented methods; Promote the construction of supervision capacity for the whole process of sewage collection and treatment, resource utilization and sludge treatment and disposal, and establish a scientific and reasonable performance appraisal system

Liu Bo stressed that the implementation plan requires rectification and standardization of pipe construction to solve the problems of rainwater and sewage diversion, pipe leakage, wrong connection and mixed connection. "It should be pointed out that the management problem is an old problem left over from the process of urban construction for decades. In addition to the management problem itself, it is more a problem that the management mechanism and quality effect supervision mechanism cannot play a role. According to the implementation plan , strengthen supervision and management, and it is necessary to go back and investigate the project construction unit. If we just focus on construction and ignore management, we will not be able to bear the consequences of reckless advance and low investment efficiency. "

the implementation plan proposes to attract financial institutions and social capital investment and guide social capital to actively participate in construction and operation. Liu Bo suggested that the government should strengthen supervision when introducing social capital and truly involving social capital. At the same time, establish a long-term investment return mechanism for municipal infrastructure, issue green bonds to repay social capital and realize a virtuous cycle

"the implementation plan emphasizes the strengths and weaknesses of making up for weaknesses. It can be predicted that it will promote the construction of urban rainwater and sewage pipes, which is highly recognized." Liu Bo said that the treatment capacity of the sewage treatment plant has been improved. Even if it meets the discharge standard, the tail water is still inferior to class V water. In the long run, it will have a great impact on the fundamental improvement of the water environment and water ecology. It is necessary to carry out ecological treatment through artificial wetlands and other methods. This also requires upgrading the existing sewage treatment plant, reducing the floor area, and transforming the saved land space into artificial wetlands

"To build an urban sewage treatment system, we must do a good job in the top-level design in combination with the higher goal of water environment and water ecological restoration. This also requires that the construction scheme should be more scientific, integrate more multidisciplinary expertise, and improve the construction management efficiency through high-tech informatization. At the same time, we should pay attention to the management system and mechanism gb/t 3098.10 ⑴ 993 mechanical properties of fasteners bolts, screws, studs and nuts, investment and financing models made of non-ferrous metals Innovative. " Liu Bo said