Wastewater treatment system and method

Abstract

The invention provides a wastewater treatment system and method. The wastewater treatment system comprises a wastewater chamber, a positive electrode chamber, a negative electrode chamber, an acid liquid chamber, an alkali liquid chamber and a buffer chamber. The wastewater chamber receives wastewater containing first ions. The positive electrode chamber and the negative electrode chamber are respectively arranged on two opposite sides of the wastewater chamber. And the acid liquid chamber is arranged between the wastewater chamber and the positive electrode chamber. And the alkali liquor chamber is arranged between the wastewater chamber and the negative electrode chamber. The buffer chamber is arranged between one of the acid liquor chamber and the alkali liquor chamber and the wastewater chamber and is used for receiving a buffer solution containing first ions; an interface between the wastewater chamber and the buffer chamber is a first ion exchange membrane, an interface between one of the acid liquid chamber and the alkali liquid chamber and the first buffer chamber is a second ion exchange membrane, and the first ion exchange membrane and the second ion exchange membrane have the same electrical property.

Description

technical field [0001] The present disclosure relates to a wastewater treatment system and method. Background technique [0002] In the existing wastewater treatment system, an electrodialysis (electrodialysis, ED) device can convert the salts in the wastewater into acid solution and alkali solution, so as to achieve the purpose of resource recovery and reduction of environmental pollution. [0003] In a conventional bipolar membrane electrodialysis device, the acid chamber, the waste water chamber and the lye chamber are arranged in sequence. In the process of wastewater treatment, the concentration of cations in the acid chamber and the anions in the alkali chamber will increase with time, while the concentrations of cations and anions in the wastewater chamber are getting lower and lower, so in the acid chamber, Concentration polarization occurs between the wastewater chamber and the lye chamber, which leads to an increase in ion migration impedance and affects the effic...

AI Technical Summary

Problems solved by technology

In the process of wastewater treatment, the concentration of cations in the acid chamber and the anions in the lye chamber will increase with time, while the concentration of cations and anions in the waste water chamber will become lower and lower, so in the acid chamber, Concentration polarization occurs between the wastewater chamber and the lye chamber, resulting in an increase in ion migration impedance and affecting the efficiency of wastewater treatment

In addition, due to the above-mentioned concentration polarization phenomenon, cations in the acid chamber and anions in the alkali chamber will diffuse back into the waste water chamber, resulting in ineffective recovery of acid and alkali

In addition, since the traditional bipolar membrane electrodialysis device only has standard anion exchange membranes and standard cation exchange membranes, it is impossible to separate ions with the same electrical properties (such as chloride ions and sulfate ions), resulting in the recovered The purity of acids and lyes decreases

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