Continue to promote the quality and efficiency of sewage treatment and work together to win the battle of green water protection

First, the pollutant composition of different industrial wastewater is very different and the concentration is high, when they are discharged into the urban sewage network time is uncertain, it is easy to cause the imbalance of carbon, nitrogen, phosphorus and other substances in the biochemical system of the urban sewage treatment plant, thus significantly reducing the treatment efficiency.

Second, some industrial wastewater may contain dangerous chemicals, persistent pollutants, pathogenic microorganisms, which may be discharged into the surface water through urban sewage treatment plants.

Third, a small number of illegal enterprises will be untreated waste water directly into the urban pipe network phenomenon occurs.

After the necessary pretreatment, the wastewater from industrial and industrial parks is integrated into the urban pipe network for unified treatment, which is the best plan at present, but it needs to be strengthened in management, technology and standard support. To this end, it is recommended that:

First, the local environmental protection department takes the lead, do a good job of industrial wastewater access to urban sewage investigation, specify the list of industries that clearly encourage and prohibit access, and determine the evaluation procedures and access standards. For those that are determined to be unable to access, they should be withdrawn within a prescribed time limit according to law, and accurately monitored and strictly "one enterprise and one tube".

(2) For those that can be accessed after assessment, the local environmental protection department shall take the lead to establish a standardized collaborative operation mechanism between wastewater discharge enterprises and urban sewage treatment plants. Reasonable planning and strict implementation of different industrial wastewater discharge time period, so that urban sewage treatment plants can maximize the use and balance of nutrient sources, and promote the quality and efficiency of urban sewage treatment.

Third, from the perspective of easy operation and easy implementation, it is more reasonable to use COD and comprehensive ecotoxicity (luminescent bacteria method) to evaluate the conditions of sodium mesh. For industrial wastewater qualified for multiple comprehensive eco-toxicity tests, the number of tests can be relaxed.

When urban sewage treatment plants submit operating cost information to the competent authorities in accordance with regulations, they can include the costs for technological transformation, intelligence introduction, management and detection level improvement, so as to appropriately improve their profitability level, so that they have the ability to constantly update sewage treatment technology and improve the level of intelligent response to risks.

Resource water shortage and quality water shortage coexist in China. Reclaimed water is of great significance to replace conventional water resources because of its stable source. However, nationwide, there are still problems such as low utilization rate of urban recycled water, insufficient sludge treatment capacity and low utilization rate of resources. It is found that the bottleneck of municipal sewage sludge resource utilization is mainly due to the lack of power of local governments and the imperfect relevant system and mechanism. To this end, it is recommended that:

First, strictly incorporate recycled water into the unified allocation of regional water resources. Governments at all levels are urged to formulate water resources allocation plans, take recycled water into account, formulate local standards that are compatible with the situation of local water resources, and introduce corresponding management measures, so that recycled water can effectively enter the government's decision-making vision, and thus accelerate the use of recycled water.

Second, improve the allocation system for the diversified utilization of recycled water. First, according to the recycled water utilization plan, the site selection and scale of the construction of urban sewage treatment plants will be re-determined according to the principle of local reuse and utilization. The second is to improve the construction of recycled water transmission and distribution network and utilization facilities, explore the inclusion of recycled water pipeline network in the overall planning of urban underground pipeline network, and increase the investment subsidy of the central budget for the construction of recycled water projects. The third is to formulate recycled water standards according to local conditions and reduce unnecessary deep treatment processes.