CN105753111A

CN105753111A - Method for treating organic wastewater by efficient peroxide flocculation technology

Info

Publication number: CN105753111A
Application number: CN201610213862.1A
Authority: CN
Inventors: 周明华; 任更波; 梁亮; 马良
Original assignee: Nankai University
Current assignee: Nankai University
Priority date: 2016-04-05
Filing date: 2016-04-05
Publication date: 2016-07-13

Abstract

The invention provides a method for treating organic wastewater by an efficient peroxide flocculation technology. According to the method, hydrogen peroxide is generated by a carbon material cathode for efficiently generating hydrogen peroxide in situ; and iron is dissolved in the treatment process as a sacrificial anode for providing a catalyst for Fenton reaction, so that multiple effects of electric flocculation, electro-Fenton, electric oxidation and the like are achieved, and the treatment property of the organic wastewater is significantly improved. The method has the outstanding advantages of good treatment effect and low energy consumption, and is suitable for treatment of non-degradable organic wastewater in dyes, chemical engineering, medicines, membrane concentrate and the like; and the pH value does not need to be adjusted.

Description

A kind of efficient peroxide flocculation technique processes the method for organic wastewater

Technical field

The invention belongs to field of environment engineering technology, relate generally to a kind of method that efficient peroxide flocculation technique processes organic wastewater.

Background technology

Electrochemical oxidation technology, due to the advantages such as oxidability is strong, controllability is good, reaction condition is gentle, equipment is simple, great potential in organic wastewater with difficult degradation thereby process, causes the broad interest of researcher.Electricity Fenton (electro-Fenton is called for short EF) and electric flocculation technique (electro-cogulation is called for short EC) are the competitive electrochemical oxidation technologies two kinds novel grown up in water treatment field in recent years.The ultimate principle of electricity Fenton is that dissolved oxygen produces H by generation electrochemistry two electron reduction on suitable negative electrode₂O₂, the hydrogen peroxide of generation and ferrous iron catalyst reaction generate the hydroxyl radical free radical (OH) with strong oxidizing property, thus reaching non-selectivity ground oxidative degradation organic pollution, react as follows:

O₂+2H⁺+2e^-→H₂O₂

H₂O₂+Fe²⁺→Fe³⁺+OH+OH^-

The ultimate principle of electricity flocculation is: under the effect of extra electric field, utilizes soluble anode, produces substantial amounts of cation, utilizes the hydroxide generated that waste water is realized coagulative precipitation.For iron anode, react as follows:

Fe→Fe²⁺+2e^-

4Fe²⁺+10H₂O+O₂→4Fe(OH)₃+8H⁺

But, acid condition, need that extra catalyst, energy consumption are higher, the shortcomings such as high concentrated organic wastewater poor processing effect are limited the application of electricity Fenton technology.Anode loss is serious, mud generation amount is big etc. is then always up the limitation of electric flocculation technique, and the process of a lot of complicated water quality waste water be there is also technical deficiency by single flocculation.Therefore, a kind of water technology efficient, that can overcome single electricity Fenton and electric flocculation technique defect is invented significant at sewage treatment area.

Summary of the invention

The purpose of the present invention is aiming at the problems referred to above, the method developing peroxide flocculation (peroxi-coagulation is called for short PC) the technical finesse organic wastewater of a kind of integrated electricity Fenton and electricity flocculation.In the process, high-efficiency carbon material negative electrode original position promotes produces hydrogen peroxide performance, and ferrum provides iron catalyst for Fenton's reaction as sacrificial anode while realizing electricity flocculation.Thus the electric flocculation of this process integration, the electricity multiple effect such as Fenton, electroxidation, can realize efficiently processing organic wastewater.

The method that the present invention processes organic wastewater is as follows: with ferrum be anode, the material with carbon element that efficiently produces hydrogen peroxide build without barrier film peroxide flocculation system for negative electrode, expose into air at negative electrode, and control electric current 50-500mA process treatment of Organic Wastewater.

The present invention has following outstanding feature and beneficial effect:

(1) the method has coupled electric flocculation, the electricity multiple effect such as Fenton, electroxidation, can realize the efficient removal of organic wastewater.

(2) pH operation interval width, it is not necessary to regulate former water pH, saves handling and uses.

(3) comparing with tradition electricity Fenton technology, this method treatment effeciency is high, energy consumption is low and without adding catalyst；

(4) comparing with the flocculation of tradition electricity, mud generation amount is few, has oxidation processes effect concurrently, more efficient.

Accompanying drawing explanation

Fig. 1 is peroxide flocculation and the contrast of electricity flocculation, electricity Fenton-like system

Fig. 2 is the impact on peroxide flocculation technique of the pH factor

Fig. 3 is the degraded to actual waste water of the peroxide flocculation process

Detailed description of the invention

The present invention is described in further detail in conjunction with accompanying drawing by following example.

In peroxide flocculation process, anode is iron plate, negative electrode is the carbon felt modified with white carbon black and PTFE；In electricity flocculation system, anode is iron plate, negative electrode is corrosion resistant plate；In electricity Fenton-like system, anode is Lead oxide brown, negative electrode is the carbon felt modified with white carbon black and PTFE.

Fig. 1 is be 80mL/min, pH at acrylonitrile concentration to be 100mg/L, electric current be 100mA, aeration rate is under 7 conditions, the contrast of peroxide flocculation and electricity Fenton, electricity Fenton-like system.It can be seen that compare with electricity flocculation with electricity Fenton, peroxide flocculation is the highest to the degradation rate of acrylonitrile, energy consumption is minimum.

Fig. 2 compared for when acrylonitrile concentration to be 100mg/L, electric current be 100mA, aeration rate are 80mL/min, the degraded impact that peroxide is flocculated by pH.It can be seen that in peroxide flocculation process, when pH is 7, acrylonitrile degradation rate is the highest.It addition, the degradation rate of acrylonitrile is not along with pH change declines significantly, therefore in peroxide flocculation process, it is not necessary to regulate pH.

Fig. 3 is the peroxide flocculation result to actual waste water.The initial TOC concentration of reverse osmosis concentrated water is 13.5mg/L, pH is 7.45, and after peroxide flocculation treatment 180min, TOC clearance is 67.6%.The initial TOC concentration of pharmaceutical wastewater is 40.5mg/L, pH is 7, and after peroxide flocculation treatment 180min, TOC clearance is 46.6%.Data above illustrates that peroxide flocculation process has good application prospect in organic wastewater with difficult degradation thereby process field such as dyestuff, chemical industry, medicine, the film dense water of process.

Claims

1. the method that an efficient peroxide flocculation technique processes organic wastewater, it is characterized in that: with ferrum be anode, the material with carbon element that efficiently produces hydrogen peroxide builds without barrier film peroxide flocculation system for negative electrode, expose into air at negative electrode, and control electric current 50-500mA process treatment of Organic Wastewater.

2. method according to claim 1, it is characterised in that described negative electrode is carbon felt, carbon fiber and by white carbon black, material with carbon element modified for PTFE.

3. method according to claim 1, it is characterised in that described anode is iron plate or ferrum net.