Coagulatory settle treatment method for rainy day overflow sewage

Abstract

A coagulating-depositing method for treating the rain sewage features that the rain sewage flows serially through static mixer, reacting pool with guide barrels and stirrer, and depositing pool with oblique pipes to reach the draining standard.

Description

technical field [0001] The invention belongs to the technical field of water pollution control engineering, and in particular relates to a coagulation and sedimentation treatment method for overflow sewage in rainy days. Background technique [0002] In order to protect the urban water environment and control water pollution, people have adopted many methods and engineering measures, mainly including: improving the collection system of urban wastewater drainage pipe network, improving the level of wastewater treatment and discharge standards. Despite this, the environmental quality of urban water bodies is still not ideal. Studies have found that the overflow of sewage pipe networks caused by urban rainy day runoff and the discharge of wastewater from rainwater pipe network pumping stations have become the main pollution sources of urban water environment. The initial runoff rainwater, the overflow sewage of the combined pipe network and the initial wastewater of the rainwat...

AI Technical Summary

Problems solved by technology

[0007] (1) Mixing is one of the three major units in the treatment process. Although the residence time is only 4-12 seconds, it is not only necessary to set up a separate mixing tank, but also to set up a more powerful stirring machine

[0008] (2) Although the mixing tank is small, but it is connected with the pipeline of the subsequent reaction tank, it is necessary to reserve enough high-level difference

In fact, the hydraulic resistance loss of this process is greater than that of piping connections between other units

This has caused difficulties in the elevation layout of the process flow

[0009] (3) The mechanical stirring and mixing method consumes a lot of energy and requires a lot of maintenance work

[0010] (4) The mixing tank is open, and the stirring paddle forms a huge hydraulic jump, which not only splashes the sewage, emits odor, and deteriorates the operating environment; more importantly, a large amount of air is brought into the sewage, because the sewage contains surfactants , and there is a large amount of organic suspended matter, which is light in specific gravity and good in affinity, so a large amount of scum layer is formed in the reaction tank, which affects the effect of sedimentation treatment and becomes an operation problem that is difficult to solve by mechanical stirring and mixing.

The partition reaction tank in the feed water is the most typical and ideal pool type with the turbulent intensity required for flocculation provided by hydraulic power, but the partition reaction tank has a complex type and a large area

The advection type sedimentation tank in the sedimentation tank can be well integrated with the reaction tank, but the change trend of its flow rate and the level of the flow direction are not conducive to flocculation and sedimentation

Although the radial flow sedimentation tank can form a flocculation area above the water inlet to strengthen flocculation, it cannot be connected with the reaction tank, which increases the floor area.

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