US-20260124654-A1 - METHOD FOR EMERGENCY REMEDIATING HALOGENATED ORGANIC CONTAMINATED SITE WITH METAL-RICH BIOCHAR

Abstract

It discloses a method for emergency remediating halogenated organic polluted site(s), by constructing a microelectric field driven bioelectrochemical system of engineering bacteria and auxiliary agent(s). The micro-electric field has cast iron electrode or copper zinc biochar electrode as the anode and plastic electrode as the cathode. The copper zinc biochar is produced by enriching copper, zinc in situ in watercanna, and then pyrolysizing, efficient improving electron transfer capability. By staged replacement of electrodes, showering engineering bacteria and auxiliary agents onto site(s), the sintered iron-rich biochar, which enriches iron in an iris, mediates extracellular electron transport of engineering bacteria and promotes the process of reducing dehalogenation of persistent halogenated organic pollutants. The present invention is particularly pronounced for emergency remediation and treatment of halogenated organic pollutants at halogenated contaminated sites with removal rates of more than 95%.

Inventors

• Lei Wang
• Shaofeng Li
• Jinhua ZHAN
• Xiaoshu WANG
• Yangyang Wang
• Jiancong LIU
• Jinsheng Wang
• Jin Liu

Assignees

• SHENZHEN POLYTECHNIC

Dates

Publication Date

20260507

Application Date

20220812

Priority Date

20210813

Claims (10)

1. 1 . A method for emergency remediating halogenated organic polluted site, characterized in that, said method comprises: constructing a bioelectrochemical system of auxiliary agent and engineering bacteria driven by a micro-electric field, and degrading halogenated organic pollutants.
2. 2 . The method according to claim 1 , characterized in that, the micro-electric field has cast iron electrode or copper zinc biochar electrode as the anode ( 5 ) and plastic electrode as the cathode ( 6 ), and power controller ( 3 ) provides a voltage of less than 1 V.
3. 3 . The method according to claim 1 , characterized in that, said auxiliary agent is iron-rich biochar, and the engineering bacteria include anaerobic engineering bacteria and aerobic engineering bacteria.
4. 4 . The method according to claim 1 , characterized in that, in the bioelectrochemical system, halogenated organic pollutants are dehalogenated and oxidized by means of staged dosing of auxiliary agent and engineering bacteria, applying electric field and replacing electrodes.
5. 5 . The method according to claim 1 , characterized in that, the method comprises: first stage: spraying anaerobic engineering bacteria I and auxiliary agent onto sites, turning on electric field and reacting, said anaerobic engineering bacteria I are selected from any one or several of Dehalococcus, Dehalopseudococcus, Dehalomonas, Rhizobium japonicum , Dehalococcoides; second stage: spraying aerobic engineering bacteria onto sites, turning on electric field and reacting.
6. 6 . The method according to claim 5 , characterized in that, in first stage, the electric field is applied with cast iron electrode as anode ( 5 ) and plastic electrode as cathode ( 6 ), and voltage supplied by power controller ( 3 ) is between 0.2 and 0.9 V.
7. 7 . The method according to claim 5 , characterized in that, said anaerobic engineering bacteria I is added in an amount of 1 to 7 kg per acre, and auxiliary agent is added at dose of less than 400 g/m 3 .
8. 8 . The method according to claim 5 , characterized in that, after turning on electric field and reacting for 8-15 h, anaerobic engineering bacteria II are sprayed again onto site soil surface and the reaction is continued for 1-5 h, said anaerobic engineering bacteria II are selected from any one or several of Flavobacterium, Enterobacter, Pseudomonas aeruginosa.
9. 9 . The method according to claim 5 , characterized in that, in second stage, in the electric field, cast iron electrode used in first phase is replaced with copper zinc biochar electrode, and the voltage applied by power controller ( 3 ) is adjusted to 0.1-0.5 V.
10. 10 . A device for emergency remediating halogenated organic pollution site, characterized in that, said device comprises an electrochemical device and a spray device ( 4 ); the electrochemical device is connected by power controller ( 3 ) between anode ( 5 ) and cathode ( 6 ); the spray device ( 4 ) and bacterial fluid storage device ( 1 ) is connected through suction pump ( 2 ).

Description

TECHNICAL FIELD The present invention belongs to the technical field of environmental protection and in particular relates to a method of emergency remediating halogenated organic polluted site(s). BACKGROUND OF THE INVENTION Much of the pollution sites in China are within urban areas, there are also a small portion of contaminated sites within ecologically sensitive areas. Since industry is the most major cause of the occurrence of contaminated sites, heavy pollution industry sites are the most dense areas of pollution sites or areas, such as petrochemicals, manufacturing, printing, landfills, filling stations, metal slag stockpiles, waste reclaiming sites and electronic waste disposal sites. Untimely remediation or treatment of pollution sites, it will potentially have a great impact on people's work, life, and will hinder the sustainable development of society, therefore pollution remediation is imminent. Main reason for formation of organic polluted sites is ability of organic matter polluting soil to enter soil of sites and generate corresponding pollution, and this part of organic pollutants are mainly halogenated organic pollutants. Haloorganics are often widely used in organic synthesis as starting materials, intermediates, solvents, etc., and are widely used in human production and life. Halogenated organic pollutants mainly include perfluorinated or partially fluorinated compounds (PFCs), chlorinated organics (COCs) and brominated organics (BOCs). Chlorophenol and perfluorooctanesulfonic acid pollutants are widely occurring, representative, recalcitrant organic pollutants, characteristics of strong persistence, remarkable biodegradability, bioaccumulation, high toxicity and ability to migrate over long distances. Once contaminated by the organic pollutants, it is very difficult to treat, and the targeted development of emergency remediation technology appears more urgent. Remediation techniques for traditionally contaminated sites are not mature and are generally performed by replacement, digging out contaminated soil, replacing it with clean soil, and it is not fundamental remediation. Currently, an emerging effective soil halo pollution technology is the electrokinetic remediation, which drives the enrichment of contaminants to the electrode region by combined electrochemical and electrokinetic actions (electroosmosis, electromigration and electrophoresis, etc.), so as to being treated or separated. It is suitable for remediating soil contaminated by halogenated organic, such as pentachlorophenol, and has the advantages of faster and lower cost of electric remediation, and is particularly suitable for remediation of a small range of viscous, diverse heavy metal contaminated soils and soluble organic contaminated soils. However, there are also drawbacks, such as requiring chemical solubilization for insoluble organic contaminants and being prone to secondary contamination. For above reasons, there is great need to seek new methods for efficient and large-scale removal of halogenated organic contaminants. SUMMARY OF THE INVENTION In order to overcome the problems described above, the present inventors have conducted a sharp investigation into methods for removing halogenated organic pollutants from halogenated organic polluted sites, and provide a method for emergency remediating halogenated organic contaminated sites, by constructing a microelectric field driven bioelectrochemical system of engineering bacteria and auxiliary agents. Said micro-electric fields employ cast iron electrodes or copper zinc biochar electrodes as the anode and plastic electrode as the cathode. Said copper zinc biochar of the copper zinc biochar electrode is produced by enriching copper, zinc in situ in watercanna, and then pyrolysizing, and efficient improvement of electron transfer capability. By staged replacement of electrodes, showering engineering bacteria and auxiliaries on site, the sintered iron-rich biochar produced by enriching iron in iris, as an aid mediates extracellular electron transport of engineering bacteria and promotes the process of reducing dehalogenation of persistent halogenated organic pollutants. The present invention is particularly pronounced for emergency treatment of halogenated organic pollutants at halogenated contaminated sites with removal rates of more than 95%. In particular, it is an object of the present invention to provide the following aspects: In one aspect, there is provided a method for emergency remediating halogenated organic polluted site, which comprises: constructing bioelectrochemical system of auxiliary agents and engineering bacteria driven by micro-electric field, and degrading halogenated organic pollutants. In another aspect, there is provided a device for emergency remediating a halogenated organic contaminated site, and said device comprises an electrochemical device and a spray device; said electrochemical device is connected by a power controller between the ano