CN107983762A - Solar photovoltaic driven bioelectrochemical soil remediation system and method - Google Patents

Abstract

The invention relates to a bioelectrochemical soil restoration system driven by solar photovoltaic, comprising a PLC control system, a solar photovoltaic system, a spray system, a biological filter bed, a support layer, a soil filling chamber and a bioelectrochemical reaction chamber; the solar photovoltaic The system includes a solar panel and a photovoltaic panel controller, the solar panel is connected to a storage battery through the photovoltaic panel controller, and the storage battery is connected to the anode electrode and the cathode electrode in the bioelectrochemical reaction chamber; the bioelectrochemical reaction A soil filling chamber is arranged above the chamber through a support layer, a biological filter bed is arranged above the soil filling chamber, and a spray system is arranged above the biological filter bed through a circulating water pump. The solar photovoltaic-driven bioelectrochemical soil remediation system provided in the above technical solution couples the solar photovoltaic system, bioelectrochemical system and microbial remediation of contaminated soil technology, which can effectively improve the degradation efficiency of soil organic pollutants.

Description

A solar photovoltaic driven bioelectrochemical soil remediation system and method

technical field

The invention relates to the technical field of soil remediation, in particular to a solar photovoltaic driven bioelectrochemical soil remediation system and method.

Background technique

With the rapid development of industrialization, the application of pesticides and sewage irrigation have had an increasing impact on the soil environment. Aiming at the status quo of soil pollution, a variety of remediation technologies such as biology, physics, and chemistry have been developed. In practical applications, physical remediation is affected by factors such as soil heterogeneity and permeability, and chemical remediation will produce more toxic side effects. product. At present, microbial remediation technology with the advantages of in-situ remediation and no secondary pollution has become a research hotspot. The slow natural purification speed of microorganisms to organic pollutants limits its practical application.

The biological filter bed process is a kind of good wastewater treatment process that integrates various purification processes such as filtration, adsorption and biological action. It integrates biological oxidation and interception of suspended solids, and has a certain degradation ability for organic pollutants. The bioelectrochemical system is a new type of biological reaction that integrates biological redox and electrochemical reactions. It utilizes the synergistic effect of biology and electrochemistry to oxidize and decompose organic pollutants. It has the characteristics of promoting the electron transfer rate and thus improving the level of biodegradation. . The study found that bioelectrochemical technology can deeply remediate oil-contaminated saline-alkali soil by improving the removal rate of total petroleum hydrocarbons in oil-contaminated soil. Studies have shown that exogenous electric energy can improve microbial activity and have an impact on microbial diversity, thus playing a positive role in maintaining the stability of pollutant removal.

Hydrophobic porous bioanode electrodes can increase the amount of microorganisms attached to the electrode, and promote the oxidation and decomposition of soil organic pollutants while increasing the adsorption amount of soil organic pollutants in the solution. Surfactants with effects such as interfacial surface tension can increase the mobility of pollutants in the soil, and can resolve and leaching the soil organic pollutants adsorbed in the soil into the aqueous solution, which has become a commonly used soil remediation technology.

Solar energy is a clean and easy-to-obtain renewable energy. The use of solar photovoltaic power to drive bioelectrochemical systems can not only improve the remediation efficiency of polluted soil, but also greatly reduce the cost of soil pollutant removal.

Contents of the invention

The main purpose of the present invention is to provide a solar photovoltaic driven bioelectrochemical soil remediation system using a solar photovoltaic system as the electric driving force, which can effectively solve the problem of persistent residual organic pollutants in polluted soil.

In order to solve the problems of the technologies described above, the present invention adopts the following technical solutions:

A solar photovoltaic driven bioelectrochemical soil remediation system, including a PLC control system, a solar photovoltaic system, a spray system, a biological filter bed, a support layer, a soil filling chamber and a bioelectrochemical reaction chamber; the solar photovoltaic system includes a solar photovoltaic system battery panel and photovoltaic panel controller, the solar panel is connected to the storage battery through the photovoltaic panel controller, and the storage battery is connected to the anode electrode and the cathode electrode in the bioelectrochemical reaction chamber; the bioelectrochemical reaction chamber is passed through The support layer is provided with a soil filling chamber, and a biological filter bed is provided above the soil filling chamber, and a spray system is provided above the biological filter bed through a circulating water pump.

Further, the biological filter bed uses sand, gravel or plastic as the filter material.

Further, a three-dimensional grid battery is provided in the bioelectrochemical reaction chamber, and the anode electrode and the cathode electrode are arranged on the three-dimensional grid battery.

Further, the anode electrode is a conductive metal organic framework material or a porous carbon material; the cathode electrode is a graphite rod or a stainless steel mesh.

Further, the components of the spray solution sprayed in the spray system are surfactants, carbon sources, nitrogen sources, phosphorus sources, metal ions and nutrients necessary for microorganisms.

Further, the spray solution contains 0-100 mg/L of surfactant per liter of water; the concentration of carbon source is 0-100 g/L; the concentration of nitrogen source is 0-10 g/L; the concentration of phosphorus source is 0-5 g/L; The metal ions are 0.1-2.0g MgSO ₄ ·7H ₂ O, 1-20mg FeCl ₃ , 0.1-2.0g KH ₂ PO ₄ , 0.05-1.0g anhydrous CaCl ₂ ; the essential nutrients for microorganisms are 0.5-5ml/L.

Further, the soil filling chamber is filled with soil to be repaired, the humidity adjustment range of the soil to be repaired is 50%-80%, and the pH is 6-8.

Further, the voltage range for driving bioelectrochemical soil remediation is 0-2V.

Further, the soil pollutants remediated by the solar photovoltaic driven bioelectrochemical soil remediation system are organic pollutants.

Furthermore, the organic pollutants are petroleum aromatic hydrocarbons, phenols and organophosphorus pesticides.

The solar photovoltaic-driven bioelectrochemical soil remediation system provided in the above technical solution uses solar photovoltaic direct current to stimulate the electrode biofilm, strengthens the degradation of soil organic pollutants by bacteria, and uses three-dimensional grid cells through the adsorption and oxidation of porous electrodes. Accelerate the electron transfer rate, increase the contact area between soil organic pollutants and electrode biofilm, combined with the efficient degradation ability of biological filter bed for pollutants, and finally form The new technology and new way of degrading soil organic pollutants can solve the problem of persistent residual organic pollutants in crude oil polluted soil.

Description of drawings

Fig. 1 is a schematic structural view of the solar photovoltaic driven bioelectrochemical soil remediation system of the present invention.

In the figure: 1. Solar panel; 2. Photovoltaic panel controller; 3. Battery; 4. Circulating water pump; 5. Manual valve; 6. Bioelectrochemical reaction chamber; 61. Cathode electrode; 62. Anode electrode; 63. Three-dimensional grid battery; 7. Support layer; 8. Soil filling chamber; 9. PLC controller; 10. Biological filter bed; 11. Spray system.

Detailed ways

In order to make the objects and advantages of the present invention clearer, the present invention will be specifically described below in conjunction with examples. It should be understood that the following words are only used to describe one or several specific implementation modes of the present invention, and do not strictly limit the protection scope of the specific claims of the present invention.

The technical scheme adopted by the present invention is shown in Figure 1, a bioelectrochemical soil remediation system driven by solar photovoltaics, including a PLC control system 9, a solar photovoltaic system, a spray system 11, a biological filter bed 10, a support layer 7, a soil A filling chamber 8 and a bioelectrochemical reaction chamber 6; the solar photovoltaic system includes a solar panel 1 and a photovoltaic panel controller 2, the solar panel 1 is connected to a storage battery 3 through a photovoltaic panel controller 2, and the storage battery 3 It is connected with the anode electrode 62 and the cathode electrode 61 in the bioelectrochemical reaction chamber 6; a soil filling chamber 8 is arranged above the bioelectrochemical reaction chamber 6 through a support layer 7, and a biological filter bed is arranged above the soil filling chamber 8 10. A sprinkler system 11 is provided above the biological filter bed 10 through a circulating water pump 4 . The above PLC control system is used to control the pH, temperature and soil moisture in the soil filling chamber.

A three-dimensional mesh battery 63 is arranged in the bioelectrochemical reaction chamber 6 , and the anode electrode 62 and the cathode electrode 61 are connected to the three-dimensional mesh battery 63 .

The anode electrode 62 is a conductive metal organic framework material or porous carbon material; the cathode electrode 61 is a graphite rod or a stainless steel mesh.

The components of the spray solution sprayed in the spray system 11 are surfactants, carbon sources, nitrogen sources, phosphorus sources, metal ions and nutrients necessary for microorganisms. Among them, the surfactant is stearic acid, quaternary ammonium salt, lecithin, fatty acid glyceride, etc.; the carbon source is glucose, sodium acetate, sodium formate, sucrose, etc.; the nitrogen source is ammonium chloride, ammonium sulfate, etc.; the phosphorus source is diphosphate Sodium hydrogen phosphate, disodium hydrogen phosphate, etc.; metal ions are K, Na, Ca, Mg, etc.; nutrients necessary for microorganisms are vitamins, amino acids, etc.

The spray solution contains 0-100 mg/L of surfactant per liter of water, and the ratio of sodium dodecylbenzenesulfonate, quaternary ammonium salt and Tween 80 is: 1:2:3-3:2:1 ; The carbon source concentration is 0-100g/L, wherein the ratio of glucose, sodium acetate, sodium formate and sucrose is: 1:1:1:1～4:3:2:1; the nitrogen source concentration is 0-10g/L; Phosphorus source concentration is 0-5g/L; metal ions are 0.1-2g MgSO ₄ 7H ₂ O, 1-20mg FeCl ₃ , 0.1-2g KH ₂ PO ₄ , 0.05-1g anhydrous CaCl ₂ ; essential nutrients for microorganisms vitamins The concentration is 0.5-5ml/L.

The soil filling chamber 8 is filled with soil to be repaired, the humidity adjustment range of the soil to be repaired is 50%-80%, and the pH is 6-8.

The voltage range for driving bioelectrochemical soil remediation is 0-2V.

The types of soil pollutants remediated by the bioelectrochemical soil remediation system driven by solar photovoltaics are organic pollutants. More specifically, the organic pollutants are petroleum aromatics, phenols, and organophosphorus pesticides.

The use steps of the present invention are as follows: fill soil into the soil filling chamber, turn on the spray system, spray the eluent containing surfactant through the upper biological filter bed and enter the polluted soil layer, and fully elute the organic pollutants into the water Phase, and then sink in the solar photovoltaic driven bioelectrochemical reaction chamber, the anode electrode in the bioelectrochemical reaction chamber adsorbs organic pollutants and efficiently degrades the pollutants into small molecules, CO ₂ and H ₂ O through the low voltage provided by the battery, After the reaction was completed, the manual valve 5 was opened to allow the reacted aqueous solution to flow to the reservoir. The circulating water pump continuously pumps the electrochemical reaction solution back to the spray system, and circulates spray to the biological filter bed for aerobic degradation, so as to realize the complete degradation and removal of pollutants.

Example 1

In this embodiment, the biological filter bed is to use sand as the filter material; the anode electrode is a nickel metal organic framework material, and the cathode electrode is a graphite rod; the voltage for driving bioelectrochemical soil restoration is 0V, the soil humidity is 50%, and the pH is 6, and the soil pollutants are petroleum aromatic hydrocarbons, phenols and organophosphorus pesticides.

The spray solution contains 0mg/L surfactant per liter of water; the carbon source concentration is 0g/L; the nitrogen source concentration is 0g/L; the phosphorus source concentration is 0g/L; the metal ion is 0.1g MgSO ₄ 7H ₂ O, 1mg FeCl ₃ , 0.1g KH ₂ PO ₄ , 0.05g anhydrous CaCl ₂ ; the vitamin concentration of essential nutrients for microorganisms is 0.5ml/L.

Example 2

In the present embodiment, the biological filter bed is made of crushed stone; the anode electrode is a zinc metal organic framework material, and the cathode electrode is a stainless steel mesh; and the voltage for driving bioelectrochemical soil restoration is 1V, and the soil humidity is 65%. The pH was 7, and the soil pollutants were petroleum aromatics, phenols, and organophosphorus pesticides.

Wherein the spray solution contains surfactant 50mg/L according to per liter of water, wherein the ratio of sodium dodecylbenzenesulfonate, quaternary ammonium salt and Tween 80 is: 1:2:3; carbon source concentration is 50g/L L, wherein the ratio of glucose, sodium acetate, sodium formate and sucrose is: 1:1:1; the concentration of nitrogen source is 5g/L; the concentration of phosphorus source is 2.5g/L; the metal ion is 1g MgSO ₄ 7H ₂ O, 10mgFeCl _3. 1g KH ₂ PO ₄ , 0.5g anhydrous CaCl ₂ ; the vitamin concentration of essential nutrients for microorganisms is 2ml/L.

Example 3

In the present embodiment, the biological filter bed is made of plastic as a filter material; the anode electrode is an iron metal organic framework material, and the cathode electrode is a graphite rod; and the voltage used to drive bioelectrochemical soil restoration is 2V, the soil humidity is 80%, and the pH is 8, and the soil pollutants are petroleum aromatic hydrocarbons, phenols and organophosphorus pesticides.

Wherein the spray solution contains surfactant 100mg/L according to per liter of water, wherein the ratio of sodium dodecylbenzenesulfonate, quaternary ammonium salt and Tween 80 is: 3:2:1; carbon source concentration is 100g/L L, wherein the ratio of glucose, sodium acetate, sodium formate and sucrose is: 4:3:2:1; the concentration of nitrogen source is 10g/L; the concentration of phosphorus source is 5g/L; the metal ion is 2g MgSO ₄ ·7H ₂ O, 20mg FeCl ₃ , 2g KH ₂ PO ₄ , 1g anhydrous CaCl ₂ ; the vitamin concentration of essential nutrients for microorganisms is 5ml/L.

The treatment performance of the bioelectrochemical soil remediation system driven by solar photovoltaics under different conditions is as follows:

Treatment performance table of solar photovoltaic driven bioelectrochemical soil remediation system under different conditions

The embodiments of the present invention have been described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments. For those of ordinary skill in the art, after knowing the content recorded in the present invention, without departing from the principles of the present invention Under the premise of , several equivalent transformations and substitutions can also be made, and these equivalent transformations and substitutions should also be regarded as belonging to the protection scope of the present invention.

Claims (10)

1. A kind of 1. bioelectrochemistry soil repair system of solar photovoltaic driving, it is characterised in that：Including PLC control system, Solar energy photovoltaic system, spray system, bacteria bed, supporting layer, soil filling room and bioelectrochemistry reative cell；It is described too It is positive can photovoltaic system include solar panel and photovoltaic panel controller, the solar panel by photovoltaic panel controller and Storage battery is connected, and the storage battery is connected with the anode electrode in bioelectrochemistry reative cell and cathode electrode；The biology Soil is provided with by supporting layer above electrochemical reaction room and loads room, bacteria bed is provided with above the soil filling room, Spray system is equipped with by water circulating pump above bacteria bed.
2. 2. the bioelectrochemistry soil repair system of solar photovoltaic driving according to claim 1, it is characterised in that：Institute It is using sand, rubble or plastics as filtrate to state bacteria bed.
3. 3. the bioelectrochemistry soil repair system of solar photovoltaic driving according to claim 1, it is characterised in that：It is raw Three-dimensional grid battery is provided with thing electrochemical reaction room, the anode electrode and cathode electrode are arranged in the three-dimensional grid electricity Chi Shang.
4. 4. the bioelectrochemistry soil repair system of solar photovoltaic driving according to claim 1, it is characterised in that：Institute It is conductive metal organic framework material or porous carbon materials to state anode electrode；Cathode electrode is graphite rod or stainless (steel) wire.
5. 5. the bioelectrochemistry soil repair system of solar photovoltaic driving according to claim 1, it is characterised in that：Spray The spray solution component sprayed in leaching system is surfactant, carbon source, nitrogen source, phosphorus source, metal ion and microorganism are required Nutrient.
6. 6. the bioelectrochemistry soil repair system of solar photovoltaic driving according to claim 5, it is characterised in that：Spray Leaching liquor is according to containing 0~100mg/L of surfactant in every liter of water；Carbon source concentration is 0~100g/L；Nitrogen concentration for 0~ 10g/L；Phosphorus source concentration is 0~5g/L；Metal ion is 0.1~2.0g MgSO₄·7H₂O, 1~20mg FeCl₃, 0.1~ 2.0g KH₂PO₄, the anhydrous CaCl of 0.05~1.0g₂；Microorganism essential nutrient element is 0.5~5ml/L.
7. 7. the bioelectrochemistry soil repair system of solar photovoltaic driving according to claim 1, it is characterised in that：Soil Earth filling interior is filled with soil to be repaired, and the humidity regulation scope of the soil to be repaired is that 50%~80%, pH is 6~8.
8. 8. the bioelectrochemistry soil repair system of solar photovoltaic driving according to claim 1, it is characterised in that：With In driving bioelectrochemistry soil remediation voltage range be 0~2V.
9. 9. the bioelectrochemistry soil repair system of solar photovoltaic driving according to claim 1, it is characterised in that：Too The soil pollution species of the bioelectrochemistry soil repair system reparation of positive energy photovoltaic driving are organic pollution.
10. 10. the bioelectrochemistry soil repair system of solar photovoltaic driving according to claim 9, it is characterised in that： Organic pollution is oil aromatic hydrocarbon, phenols and organophosphorus pesticide.