Method for treating waste water by electrochemically enhancing biological coupling system

Abstract

The invention provides a method for treating waste water by enhancing a zero-valent iron-biological coupling system with an external electric field. Iron filler is arranged in an iron filler reaction zone; the upper and lower ends of the iron filler are provided with a corresponding number of electrode rods respectively; the total number N of the electrode rods is determined according to a formula, wherein alpha is selected from 0.1 to 0.8; the space between adjacent electrode rods at each end of the iron filler is selected from 0.3 to 0.5m; and the length L of the part of the electrode rod inserted in the filler zone is designed according to the formula: L=0.45H. An AC power supply of 0 to 12V is arranged outside the iron filler reaction zone; and the two electrode rods corresponding to the upper and lower ends of the iron filler are connected with the AC power supply respectively. By means of the external electric field, the redox effect of the zero-valent iron is enhanced, and the degradation of high molecular non-degradable substances is accelerated so as to provide more favorable conditions for the biological treatment, reduce the sludge deposition on the zero-valent iron andimprove the waste water treatment effect of the zero-valent iron-biological coupling system.

Description

1. Technical field The invention relates to a method for treating wastewater by using an external electric field to strengthen a zero-valent iron-biological coupling system, and belongs to the technical field of wastewater treatment. 2. Background technology Due to the increasing complexity of wastewater composition, the effectiveness of conventional biological treatment technologies is limited. For the treatment of refractory biodegradable wastewater, the combined process of zero-valent iron and biology is widely used at present. In general, the process adopts a two-stage reactor, that is, the biological zone and the iron filler reaction zone are separated, and an intermediate sedimentation tank is set between the two, and the mixed liquid reflux is used to realize the coupling of the biological and iron fillers. The principle It mainly uses zero-valent iron to carry out oxidation-reduction effect on biologically harmful organic substances, heavy metals and other substance...

AI Technical Summary

Problems solved by technology

However, in practical applications, due to the difference in water quality requirements for the chemical and biological reactions of zero-valent iron, under the premise of ensuring biological treatment conditions, the reaction kinetics of zero-valent iron is low, and zero-valent iron is easy to be covered by organisms, and the surface loses activity. The electrochemical reaction is inhibited, and the synergistic effect of the two is not fully exerted