Circulating water-saving type sewage treatment method

Abstract

The invention relates to a circulating water-saving type sewage treatment method. The circulating water-saving type sewage treatment method is characterized by comprising the following steps of (1) mixing of polyaluminium chloride; (2) mixing of amide; (3) air floatation; (4) scraping of slag; (5) discharging of the slag; (6) detecting of chemical oxygen demand of intermediate water: when the standard is reached in detection, introducing the intermediate water into a biochemical tank, and draining; when the standard is not reached in the detection, introducing the intermediate water into a circulating water tank; (7) detection of turbidity: according to the detection result, respectively introducing the intermediate water in the circulating water tank into a polyaluminium chloride mixing tank and an air floatation tank through a mixing water pump and an air floatation water pump for recycling. The circulating water-saving type sewage treatment method has the advantages that the intermediate water at the middle layer obtained after the air floatation is cyclically introduced into the polyaluminium chloride mixing and air floatation processes, so that while the incompletely purifiedsewage is further purified, the incompletely purified sewage is used for replacing running water as air floatation water, and the usage amount of the running water is reduced; the sewage treatment effect is improved, and the drainage of the sewage can reach the standard.

Description

technical field [0001] The invention relates to a sewage treatment method, in particular to a circulating water-saving sewage treatment method. Background technique [0002] In the prior art, sewage treatment usually adopts the process of mixing polyaluminum and amide, flocculation, air flotation, scraping and removing slag, then overflows the middle water and then enters the biochemical tank. During the treatment process, due to the high concentration of sewage and the poor flocculation effect of polyaluminum and amide, it is necessary to add a large amount of tap water to dilute the sewage. The mass ratio of the daily treated sewage to the mass ratio of the required tap water usually reaches 1: 1 or even higher. At the same time, a large amount of tap water needs to be added for air flotation during the air flotation process, which further causes a lot of waste of tap water resources. The reaction time of sewage in the biochemical pool will lead to poor treatment effect a...

AI Technical Summary

Problems solved by technology

During the treatment process, due to the high concentration of sewage and the poor flocculation effect of polyaluminum and amide, it is necessary to add a large amount of tap water to dilute the sewage. The mass ratio of the daily treated sewage to the mass ratio of the required tap water usually reaches 1: 1 or even higher. At the same time, a large amount of tap water needs to be added for air flotation during the air flotation process, which further causes a lot of waste of tap water resources. The reaction time of sewage in the biochemical tank, resulting in poor treatment effect and substandard sewage discharge

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