Method for treating and printing and dyeing wastewater by using hydrolysis tank

Abstract

The invention discloses a method for treating and printing and dyeing wastewater by using a hydrolysis tank. The hydrolysis tank comprises a front half tank and a rear half tank, wherein the front half tank of the hydrolysis tank is provided with a water inlet; the rear half tank of the hydrolysis tank is provided with a water outlet; the rear half tank is connected with an oxidation ditch and a secondary sedimentation tank in series; the front half tank is an opened tank of which the upper part is opened; the rear half tank is a closed tank of which the upper part is closed; the printing anddyeing wastewater is treated and then is mixed with sludge in the secondary sedimentation tank at the water inlet; the mixture enters the inside of the front half tank of the hydrolysis tank from thelower part of a baffle plate; when DO value of the printing and dyeing wastewater reaches 0.2-0.3mg / L, the wastewater enters the interior of the rear half tank of the hydrolysis tank; and when the DOvalue of the printing and dyeing wastewater reaches 0.3-0.5mg / L, the wastewater is discharged after reaching the standard. According to the method disclosed by the invention, the biochemical quality of the hydrolysis tank is greatly improved; the ammonifying effect of organisms which are difficult to degrade, such as organic nitrogen, is remarkably improved; and the removal rates of subsequent COD (Chemical Oxygen Demand) and NH3-N are greatly improved.

Description

(1) Technical field [0001] The invention relates to a wastewater treatment method, in particular to a method for treating printing and dyeing wastewater by using a hydrolysis tank. (2) Background technology [0002] The printing and dyeing industry is closely related to the lives of the people in our country and occupies a very important position in the national economy. However, the annual discharge of printing and dyeing wastewater pollution is also considerable. According to relevant domestic and foreign data estimates, the water consumption for processing a piece of cotton fabric is about 1-1.2m 3 . Printing and dyeing wastewater is characterized by large water volume, high content of organic pollutants, low B / C ratio, deep chroma, high alkalinity, and large changes in water quality. It is a difficult-to-treat industrial wastewater. As the sustainable development strategy has become the consensus of people all over the world, my country has gradually increased the inte...

AI Technical Summary

Problems solved by technology

At present, there are many design schemes for the design of hydrolytic acidification tanks. The bottom perforated water distribution type is widely used, but for the traditional design of hanging film type hydrolysis acidification tanks, it has been applied to a certain extent in the field of printing and dyeing wastewater, but there are almost no successful cases. Basically, a large amount of facultative mud in the hydrolytic acidification tank is deposited on the bottom, resulting in a decrease in the effective tank capacity and a decrease in treatment efficiency

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