Academician Qu Jiuhui talks about comprehensive treatment of rural water environment

    The water quality of urban and rural drainage in China is very different from that of rural areas. Generally speaking, the water quality in Northeast, northwest and southwest is slightly lower, while that in Southeast and North China is slightly higher. And there is another problem in the water consumption, namely, flushing and bathing. At present, most rural toilets are dry toilets, so the water consumption is relatively small, and the frequency of bathing is not high in the city. Therefore, in cities, the water consumption per person is 75 to 220 per day. However, there is no clear statistics for rural areas until now. This indicates that the law of urban sewage discharge is very strong, and in rural areas, because of the unstable water consumption and large regional differences, the discharge coefficient is different. In addition, the discharge mode of sewage is different between rural and urban areas. The urban sewage is basically discharged into the sewer, while there are many rural ways, such as kitchen swill used for feeding, domestic sewage spilling and so on. Finally, the collection system is basically collected and treated by the pipe receiving and pipe network in the city. However, the rural collection method is very different. If the pipe diameter is too small, the flow rate is too slow and easy to be blocked; if the pipe diameter is too large, it will become a sedimentation tank. In the whole rural collection system, the collection method should be determined according to the rural water quantity and flow rate, and the collection method of the city cannot be copied. This is related to the standard making, for example, some rural areas can realize the utilization of resources, and some of them can be discharged directly into the river. Therefore, there will be a great difference between the rural sewage and the decentralized sewage treatment standards in different regions of China. At present, the standards for the discharge of rural domestic sewage or facilities pollutants formulated by different regions are not perfect enough, and the social and economic conditions and environmental conditions in rural areas will also have a certain impact on them. However, I think the formulation of rural domestic sewage standards is very important. In the past, we have copied some of the municipal sewage treatment standards, which is not advisable. In the future, we must have the sewage discharge standards specially used in rural areas, and this standard should not be unified nationwide, and should be considered according to the actual situation of each region. At present, the Ministry of housing and construction is coordinating the work after the establishment of rural sewage discharge standards. In the future, we should not only establish standards, but also guide facilities, including operation and maintenance, which is also of great significance for rural sewage treatment. The thinking about the mode of agricultural sewage treatment should consider three aspects: one is technology and engineering mode, which should emphasize applicability and simplicity; the other is to emphasize operation and management mode, which requires reasonable and stable, and has current guarantee; third, there should be an industrial and market model. First of all, for technology and engineering mode, the most important thing is the practicability of technology and the simplicity of process flow. There are five aspects in this: simple, suitable for local environment and conditions, the simplest method to achieve stable standards; energy saving method with low consumption, no power or less power; efficient method with the lowest cost of economy, construction and operation; intelligent method of easy management and easy integration of system management; and cleaning method for local simple utilization and material recycling. There are many modes of rural sewage treatment, including household treatment, local treatment in natural villages and centralized treatment by pipe, but which is the most suitable one? I think it is still suitable for local conditions and economic application. In rural areas, it is necessary to emphasize the priority of reuse. If the sewage in rural areas can be used by itself without discharge, this is the best way to dispose of it. It is unnecessary to treat the nitrogen and phosphorus to a certain standard. It is an optimal method to recycle the nitrogen and phosphorus to the land for comprehensive utilization of nitrogen and phosphorus. Therefore, in rural areas, a sustainable sewage and waste treatment mode should adapt to changes, adapt to the new rural construction, urbanization land use and construction mode of the country and local. In the next decade, the structure of rural production and living and lifestyle in China will change greatly. If we stay in the current cognition for sewage treatment, it will certainly be useless in the next ten years. In the operation and management mode, the operation and management of rural water environment management should conform to three aspects: reasonable objectives, high efficiency of wisdom and stable income policy guarantee. The goal is reasonable, which means that the environmental protection objectives of the watershed or region should be compatible, and the standards must be adjustable, and they should be economically and technically feasible. For example, the U Quality standards. The emission limitation standards and standards in China should also be based on technology, and the emission limits of pollutants should be determined according to the process technology, pollutant production level and treatment technology of different industries. At present, the standards of water environment and sewage discharge in rural areas are basically formulated according to the discharge standards of cities. However, the rural conditions are totally different from those of cities. The standards of rural water environment must be sustainable, and their ecological safety and the systematic management under the premise of risk warning and risk warning should be considered. The ecological bearing capacity of the water body must be considered The mode selection, if the urban thinking to establish the rural water environment standard is not desirable. Intelligence is not digital, but intelligent. At present, many people often understand the intelligence as digital, or replace it with digital, which is not rigorous. Artificial intelligence is an important area in the next ten years. How to introduce it into rural water environment management, build a digital management platform for the drainage, solid waste, toilet, culture and other discharge sources and the whole system of treatment in villages and towns, form an integrated management and control and operation and maintenance intelligent network system, and also an important choice for the future market and technology. For the rural water environment governance policy, we should first formulate professional operation management. The single household management in the United States is a lesson. China's rural areas should not adopt this way. The management of one household will cause great trouble to the future management, and cannot be used continuously. Therefore, specialized operation institutions should be established for operation. At the same time, there should be third-party supervision, scientific indicators and reward and assessment mechanism. Finally, the policy must be stable and win. The government can not only consider itself, but also make the enterprise profitable while realizing the government performance. This is the policy incentive mechanism of stable and win-win. Regarding the choice of industry and market mode, the next ten years must be the transformation from quantity competition to quality competition, engineering competition to technology competition, and project competition to service competition. Enterprises should have innovative path, control the market accurately and find their own core technology. The core technology of rural water environment management and the core technology of urban environmental governance or other industries are different. They should have the transformation ability of technology product and equipment. In the future, the product, equipment, equipment and systematization are the governance of rural water environment An important direction is also the key point for enterprises to show their competitiveness in the core technology and process market. In terms of the future development of rural water environment management industry, there are four key points of industrial technological innovation: one is the local resource of waste; the other is artificial intelligence technology for rural water environment management; the third is equipment, systematization and standardization; the fourth is the integrated management and service platform of the whole system. In a word, the future market competition is two points: technology and service, and technology and service must complement each other. Technology is the support. Only with the continuous progress of key technologies and product promotion can we win the position in this market. Service is the core. Only enterprises with modern service consciousness, service ability, service system and service quality can dominate the market.

    Editor Li Xiaowei reviews Bu Xiaolei

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