CN103286121A

CN103286121A - Two-dimensional inhomogeneous electric field experiment method used for electrokinetic restoration of polluted soil

Info

Publication number: CN103286121A
Application number: CN2013102455365A
Authority: CN
Inventors: 顾莹莹; 付融冰; 李鸿江
Original assignee: China University of Petroleum East China
Current assignee: China University of Petroleum East China
Priority date: 2013-05-09
Filing date: 2013-06-19
Publication date: 2013-09-11
Anticipated expiration: 2033-06-19
Also published as: CN103286121B

Abstract

The invention provides a method for the electrokinetic restoration of polluted soil through using a two-dimensional inhomogeneous electric field experiment apparatus used for the electrokinetic restoration of the polluted soil. The apparatus comprises a soil tank, gas measuring devices, a liquid circulating and measuring device, an electrode control system and a data acquiring system. The soil tank comprises a tank body, a top cover, a bottom cover and a bolt; the top cover and the bottom cover are respectively provided with a center nut and a plurality of other nuts positioned surrounding the center nut, having a symmetric center and being annular in shape, and electrodes are arranged between upper nuts and lower nuts; a plurality of probes are uniformly distributed on the top cover; the gas measuring devices are scale tubes; the liquid circulating and measuring device comprises a connecting tube, a total shunt tube, a peristaltic pump and liquid measuring devices; the electrode control system is connected with the electrodes; and the data acquiring system is connected with the probes. The method using the apparatus and appropriate technological parameters is very in favor of removing pollutants and saving the energy consumption, has a high system stability, and has test values and application prospects.

Description

A kind of two-dimentional inhomogeneous field experimental technique for electric restoring polluted soil

Technical field

The present invention relates to a kind of method for pollutant purification and processing, relate to a kind of two-dimentional inhomogeneous field experimental technique for electric restoring polluted soil especially, belong to environmental protection and prevention and cure of pollution and improvement field.

Background technology

Along with continuing of China's process of industrialization, and in the agricultural production agricultural chemicals heavy dose, on a large scale, the use of long expiration, thereby accumulated comparatively serious soil pollution, for example, in polluted enterprises or areal of industrial concentration, industrial and mineral mining area and surrounding area, city and area, outskirts of a town soil heavily contaminated district and high risk area have appearred.Meanwhile, the type of soil pollution also presents variation, complicated trend, for example, a lot of areas have the old and new's pollutant and deposit, the severe situation of inorganic organic combined pollution.

Soil pollution has tangible threat to ecological environment, drinking water source, agricultural product quality and health etc., in view of this, a large amount of further investigations has been carried out for the prevention of contaminated soil, improvement, harmless treatment etc. in countries in the world, tries hard to find the contaminated soil processing method of quick, low energy consumption, high cost effectiveness.And compare with western developed country, China is just at the early-stage aspect soil remediation and reparation, and practical, simple and effective soil pollution recovery technique and new device are had urgent demand.

At present, the recovery technique of traditional contaminated soil mainly contains advanced oxidation processes, stable/curing technology, chemical leaching method, high temperature pyrolytic cracking (HTP), phytoremediation method, microorganism repairing method, gas phase extraction process etc.But all there are many shortcomings in these methods, easily the physicochemical property of soil are caused severe bad influence as advanced oxidation processes; Stable/curing technology has just been realized the stable of heavy metal and has been solidified, can't fundamentally reduce the total metals in the contaminated soil; The chemical leaching method is only effective to specific soil and pollutant, and the scope of application is less, and elution efficiency is low; The power consumption of high temperature pyrolytic cracking (HTP) is bigger, and the physicochemical property of soil is also had adverse effect; Though phytoremediation method cost is lower, and is simple to operate, efficient is low excessively, and is consuming time too very long; The cost of microorganism repairing method is higher, and repairing efficiency is long; The gaseous phase of soil extraction process is applicable to the reparation of high volatile volatile organic matter such as contaminated soils such as gasoline, benzene and tetrachloro-ethylene, and except efficient lower, the cycle is longer.

All this kind has caused the range of application of said method and using value all to be subjected to certain restriction, can't promote on a large scale.In the last few years, the electronic repairing method of contaminated soil obtained paying attention to day by day, and scientist has carried out research extensively and profoundly to it, has developed multiple electric repair method and related device.

CN1695834A discloses a kind of electrodynamics restorative procedure of heavy-metal contaminated soil.Described method adopts amberplex with negative electrode and is tried soil sample and separate, and places control amberplex obstruction between amberplex and the soil, the H that utilizes electrode self to produce with porous ceramics ⁺And OH ^-, and by the iris action of amberplex, pH in soil in the control electrodynamics repair process is accelerated stripping and the migration of pollutant.

CN201454977U discloses a kind of electric power and has adsorbed compound restoration of soil polluted by heavy metal device.Described device comprises and adopts graphite to make electrode, electrode comprises anode and negative electrode, anode places the anode region, negative electrode places the cathodic region, by the anode region to the cathodic region, set gradually the porous adsorbing material active carbon of the porous adsorbing material active carbon of the dividing plate that prevents heavy metal ion diffusion, absorption heavy metal, the heavy-metal contaminated soil that needs to handle, absorption heavy metal and prevent the dividing plate of polluted heavy metals ions diffusion, for the rising that prevents cathode zone pH and the decline of anode region pH, and adopt the method for switching polarity of electrode.

CN1899717B discloses the technology of a kind of electric power and iron permeable reactive barrier renovation of heavy metal polluted soil with combined.Described technology is that graphite electrode is installed in the soil both sides, lay the iron wall between two electrodes and pending soil, connect power supply, under electric field action, anionic metal is moved near the anode, and metal cation is moved near the negative electrode, reacts with it when heavy metal passes the iron wall and is adsorbed, reduces and precipitate.

CN202356398U discloses the electronic prosthetic device of removing heavy metal in soil and organic pollution.Described device comprises electronic reparation post, electrode, electrolytic cell, electrolyte treatment pond, acidometer and dc source, by the pH automatic control system, guarantee the comparativity between the result, improved control accuracy, can improve the removal effect of pollutant in the contaminated soil.

CN102500610A discloses a kind of method of electrodynamics associating drip irrigation restoration of soil polluted by heavy metal.Described method is that positive and negative electrode is installed at the contaminated soil two ends, and between positive and negative electrode and contaminated soil, place adsorbent, above near the soil adsorbent, drip irrigation appliance is set, electrolyte, buffer solution or complexing agent etc. are added drop-wise in the soil of both sides, electrode is carried out periodicity to be switched, thereby it is adsorbed that heavy metal is adsorbed agent by the electrokinetic migration effect, thereby reduce the concentration of heavy metal in soil.

CN102806228A discloses the electronic prosthetic device of a kind of contaminated soil heterotopic and method.Described device comprises soil bearing system, electrode system and electrode working solution spray system, and when work, the top electrode of electrode system is electrically charged opposite with bottom electrode institute.

CN102896143A discloses a kind of powered surface activating agent associating repairing polluted soil experimental provision.Described device comprises the main body that contaminated soil and uncontamination soil are housed, the two side portions of corresponding contaminated soil vertically is equipped with two parallel electrode chamber perforated baffles in main body, two perforated baffles and main body inner surface form two electrode chambers, electrode respectively is housed in electrode chamber, by electrode is applied electric current, can improve the treatment effect of contaminated soil.

CN202667240U discloses a kind of oil-polluted soils prosthetic device based on high-pressure electrostatic.Described device comprises high voltage source, high-pressure electrostatic soil treatment part, high-pressure electrostatic vacuum part, insulated part, described high-pressure electrostatic soil treatment partly comprises electrode, form discharge by pressurization between electrode, petroleum hydrocarbon in the contaminated soil can be decomposed, it is adsorbed by the high-pressure electrostatic vacuum part to decompose the noxious material that generates.This device is mainly used in the reparation of the contaminated soil that Petroleum Production and carrier cause.

As mentioned above, though people have researched and developed multiple electronic prosthetic device and method, all have some shortcomings, for example: 1. the board-like materials that use are done electrode more.2. positive and negative electrode is distributed in the both sides of contaminated soil and causes pollutant to move linearly, and enters the dead air space of soil probably and can't move to electrode tip.3. important parameters such as the electrodialysis stream in can't the experiments of measuring process and gas production rate.4. can only form uniform and stable uniform electric field, can't freely switch positive and negative electrode or switch loaded down with trivial detailsly, cause the energy consumption height, and system's fluctuation of service.

For these reasons, administering the field at contaminated soil at present, still have tight demand for contaminated soil prosthetic device and method novel, respond well, high removal effect, also is research emphasis and the focus in present soil remediation field.

Summary of the invention

Shortcomings and deficiencies in view of above-mentioned technology, the inventor is from point of practical use, device to electric restoring polluted soil has carried out a large amount of further investigations, after having paid creative work, develop a kind of device of electric restoring polluted soil and use the method for this device, this device can continue to add additive or synergist in experimentation in soil, as complexing agent, chelating agent, surfactant, acid-base salt solution, cushioning liquid, microorganism waits to promote the desorption of pollutant in soil, degraded or various chemical reaction process, the more important thing is by electrode control system the electrode of arranging is controlled, thereby produced inhomogeneous field, can make pollutant in the soil such as heavy metal etc. that the non-rectilinear two dimensional migration takes place, and can the neutralize pH of each electrode of the use by peristaltic pump, cut down the consumption of energy, be convenient for measuring the electrodialysis stream in the experimentation simultaneously, gas, important parameters such as voltage, help to analyze the electric power repair mechanisms, have a good application prospect and be worth, be better than all similar device and methods at present in various indexs.

For achieving the above object, the invention provides a kind of experimental technique that uses two-dimentional inhomogeneous field experimental provision repairing polluted soil, it is characterized in that: described device comprises soil sample groove, gas measurement device, liquid circulation and measurement mechanism, electrode control system and data collecting system;

Described soil sample groove comprises cell body, top cover, bottom, and is used for the fixedly bolt of cell body, top cover, bottom; The opposite position of described top cover and bottom is provided with a plurality of nuts, and one of them nut is positioned at the center, all the other nuts be positioned at this center nut around, and be symmetrical centre and ringwise or regular distribution with described center nut; Be provided with electrode between the lower nut corresponding on described, i.e. contre electrode and a plurality of ring electrode; Also be evenly distributed with a plurality of probes that extend into described soil sample groove inside on the described top cover;

Described gas measurement device is the graded tube that links to each other with each electrode upper end;

The circulation of described liquid and measurement mechanism comprise the tube connector that links to each other with the contre electrode lower end, by the isocon that links to each other with the ring electrode lower end converge total isocon of forming, the peristaltic pump that links to each other with total isocon with described tube connector, respectively with tube connector end and the total device for measuring volumetric flow of fluid that links to each other of isocon end;

Described electrode control system links to each other with each electrode;

Described data collecting system links to each other with each probe;

Wherein, in the method, adopt any step mode of following (1)-(4) to carry out electronic reparation:

(1). be the center of circle with the contre electrode, clockwise or counterclockwise contre electrode and the ring electrode that becomes the bilateral symmetry of same straight line to distribute are with it switched on and be connected, on each connects, regularly change polarity of electrode, before switching to next the connection, repeatedly change polarity of electrode, until finishing once complete energising, so repeat to finish the electronic reparation of soil;

(2). be the center of circle with the contre electrode, clockwise or counterclockwise contre electrode and the ring electrode that becomes the bilateral symmetry of same straight line to distribute are with it switched on and be connected, on each connects, do not change polarity of electrode from start to finish, behind the energising certain hour, switch to the next order that connects, finish once complete energising after, change polarity of electrode and carry out complete energising next time, so repeat to finish the electronic reparation of soil;

(3). be that the mode of cycling element is switched on " A+mB ":

A: be negative electrode with the contre electrode, ring electrode is anode and antianode and negative electrode are switched on simultaneously;

B: be the center of circle with the contre electrode, clockwise or counterclockwise contre electrode is connected energising in turn with the ring electrode that the bilateral symmetry that becomes same straight line with it distributes, on each connects, regularly change polarity of electrode, before switching to next the connection, repeatedly change polarity of electrode, until finishing once complete energising;

Wherein m is integer, and 1≤m≤4;

(4). be that the mode of cycling element is switched on " A+nC ":

C: be the center of circle with the contre electrode, clockwise or counterclockwise contre electrode and the ring electrode that becomes the bilateral symmetry of same straight line to distribute are with it switched on and be connected, on each connects, do not change polarity of electrode from start to finish, behind the energising certain hour, switch to the next order that connects, until finishing once complete energising;

Wherein n is integer, and 2≤n≤4, and finishes when switching to the complete energising of next C after C energising the change polarity of electrode.

In this application, unless otherwise prescribed, the implication of " complete energising " refers to switch on when connecting the position of getting back to initial contre electrode and the ring electrode of the bilateral symmetry distribution that becomes same straight line with it again, also namely finishes a circumference circulation.

In the experimental technique of the two-dimentional inhomogeneous field experimental provision of use of the present invention repairing polluted soil, the 3D shape of the cell body of described soil sample groove is special the restriction not, for example can be cylindrical, cuboid, the square bodily form etc.Its volume is special the restriction not, can carry out suitable selection according to soil treatment amount, practical operation situation.Also there is no particular limitation for its material, as long as it has certain intensity, insulate and can bear the pressure when operating, non-limiting ground for example can be polyester material, safety glass, PVC etc.

In the experimental technique of the two-dimentional inhomogeneous field experimental provision of use of the present invention repairing polluted soil, described top cover and bottom lay respectively at the upper and lower of described cell body, and can cover described cell body fully, thereby constitute a sealed volume space with the pending contaminated soil of packing into cell body.The material of described top cover and bottom does not limit especially, as long as it has certain intensity, insulate and can bear the pressure when operating, non-limiting ground for example can be polyester material, safety glass, PVC etc.

In the experimental technique of the two-dimentional inhomogeneous field experimental provision of use of the present invention repairing polluted soil, described cell body, top cover and bottom are fixed together by bolt, namely at the superimposed place of described cell body, top cover and bottom, bolt passes top cover, cell body and bottom from top to bottom in turn; Perhaps described top cover and bottom are greater than the horizontal section area of cell body, and namely the edge of top cover and bottom stretches out outside the cell body, and bolt passes the marginal portion of stretching out of top cover and bottom from top to bottom, thus with cell body tightly " folder " live, realize that this three's is fixing.By said fixing, can form a confined space that holds pending contaminated soil.Preferably, in order to seal better, between described top cover and cell body, and the sealing ring that is provided with its sealing function between described bottom and the cell body.Non-limiting ground, described sealing ring material can be any known sealant material, as can be various caulking gums, enumerates acrylonitrile-butadiene rubber, fluorubber, silicon rubber or ACM etc. non-limitingly.

In the experimental technique of the two-dimentional inhomogeneous field experimental provision of use of the present invention repairing polluted soil, described top cover and bottom are provided with a plurality of nuts at opposite position, one of them nut is positioned at the center of described top cover and bottom, all the other nuts be positioned at this center nut around, and be symmetrical centre and distributing ringwise with described center nut.On top cover and bottom corresponding, be provided with electrode between the lower nut, namely up and down two center positions be contre electrode, a plurality of electrodes formation ring electrodes at all the other nut location places.

In the experimental technique of the two-dimentional inhomogeneous field experimental provision of use of the present invention repairing polluted soil, the quantity of described ring electrode is special the restriction not, can carry out suitable selection and/or definite according to the area size of described cell body horizontal section, thereby the center with contre electrode presents the symmetric arrays that is evenly distributed, for example in the distance to contre electrode, described ring electrode can only be a circle around contre electrode, also can be multi-turn around contre electrode, for example enclose for 2-4." circle " herein is not the form of refering in particular to circle, comprised and the equidistant form of arranging of soil sample groove edge yet.

In the experimental technique of the two-dimentional inhomogeneous field experimental provision of use of the present invention repairing polluted soil, as preferred embodiment a kind of, described electrode (unless otherwise prescribed, when with " described electrode ", " each electrode " use, mean described contre electrode and ring electrode, down with) be hollow form.More preferably, for the described electrode electrode tube wall of hollow form is provided with aperture to flow into for liquid and to flow out, for example these apertures can evenly distribute, and the aperture can be 0.5mm-5mm, for example can be 0.5mm, 1mm, 2mm, 3mm, 4mm or 5mm.

In the two-dimentional inhomogeneous field experimental provision of described electric restoring polluted soil of the present invention, as preferred embodiment a kind of, described electrode periphery is provided with leak-proof device, influences normal operation and the loss of electrode to prevent soil particle from entering into hollow electrode.Described leak-proof device is special the restriction not, as long as can stop soil particle to enter in the electrode, for example can be filter paper, filter cloth or filter screen.

In the experimental technique of the two-dimentional inhomogeneous field experimental provision of use of the present invention repairing polluted soil, also be evenly distributed with a plurality of probes that extend into described soil sample groove inside on the described top cover, in brief, namely have equally distributed aperture to insert probe at top cover, can tighten probe then and realize fixing.The length of described probe is not special restriction, as long as it can extend in the soil and not touch bottom, for example it can be the 1/3-2/3 of electrode length.The two-dimentional voltage that the purpose that described probe is set is to measure pending soil distributes, thereby finishes data acquisition, determines the parameters such as voltage gradient that apply, for operation carry out smoothly provide the most direct data to show with mensuration as a result etc.The type of described probe is special the restriction not, as long as it can measure the voltage that produces in the soil, can be any known voltage probe.

In the experimental technique of the two-dimentional inhomogeneous field experimental provision of use of the present invention repairing polluted soil, described gas measurement device is the graded tube that links to each other with each electrode upper end, but this graded tube top is provided with the opening of opening and closing of fault, when sealing, can determine the volume of gas by the decline of liquid level.When not measuring gas volume, then be in opening, keeping liquid level place pressure is environmental pressure.

In the experimental technique of the two-dimentional inhomogeneous field experimental provision of use of the present invention repairing polluted soil, the circulation of described liquid and measurement mechanism comprise the tube connector that links to each other with the contre electrode lower end, by the isocon that links to each other with the ring electrode lower end converge total isocon of forming, the peristaltic pump that links to each other with total isocon with described tube connector, the device for measuring volumetric flow of fluid that links to each other with tube connector end and isocon end.

Wherein, an end of described tube connector links to each other with the contre electrode lower end, and the other end connects described device for measuring volumetric flow of fluid.Described isocon connects all ring electrode lower ends, and merges into a total isocon.Described peristaltic pump links to each other with total isocon with tube connector, and peristaltic pump is special the restriction not, as long as it can carry out circulating reflux with the liquid in the device for measuring volumetric flow of fluid, can use any known peristaltic pump.By using peristaltic pump and selecting its wriggling direction as required, and the liquid from male or female can be back to respectively in negative electrode or the anode, thereby can in and pH value, avoided the precipitation of pollutant under acidity/alkali condition that causes because of the too high or too low of pH value.

Wherein, described tube connector all is connected a three-way pipe with the end of total isocon, and the path of described three-way pipe by the wherein liquid of self-electrode in the future flow in the described device for measuring volumetric flow of fluid, and another path then communicates with atmosphere.

Wherein, the liquid that flows out from electrode can part be back in the electrode by described peristaltic pump, to realize the neutralization of pH value, and remainder can enter the device for measuring volumetric flow of fluid discharge, to reach the purpose of removing pollutant, rehabilitating soil, the amount that is back to electrode can be carried out suitable selection according to the degree that neutralizes.

In the experimental technique of the two-dimentional inhomogeneous field experimental provision of use of the present invention repairing polluted soil, described electrode control system links to each other with each electrode.By described electrode control system, can control and switch the polarity of contre electrode and all ring electrodes etc., thereby soil is applied inhomogeneous field, realize moving process and the pattern of control pollutant, be convenient to study the migration of pollutant and remove mechanism, thereby realize good measurement and pollutant removal.

Wherein, in the method, can adopt above-mentioned step mode (1) to carry out electronic reparation, preferably, mode (1) is as follows:

(1). be the center of circle with the contre electrode, clockwise or counterclockwise contre electrode and the ring electrode that becomes the bilateral symmetry of same straight line to distribute are with it switched on and be connected, be t hour the conduction time on each connects, on connecting, each begins during in energising, switching on changed polarity of electrode after t1 hour, continued to switch on t2 hour until setting-up time t, switched to next energising then and connected, until finishing once complete energising, so repeat to finish the electronic reparation of soil.

Wherein, in the method, can adopt above-mentioned step mode (2) to carry out electronic reparation, preferably, described step mode (2) is as follows:

(2). be the center of circle with the contre electrode, clockwise or counterclockwise contre electrode and the ring electrode that becomes the bilateral symmetry of same straight line to distribute are with it switched on and be connected, on connecting, each does not change polarity of electrode, and after reaching t3 hour conduction time, switching to next energising connects, until finishing once complete energising, changing polarity of electrode then, to carry out next each energising connect hours be t4 hour complete energising, so repeating each energising, to connect last conduction time be the complete energising of t3 and t4, until finishing the electronic reparation of soil.

Wherein, in the method, can adopt above-mentioned step mode (3) to carry out electronic reparation, preferably, described step mode (3) is as follows:

(3). be that the mode of cycling element is switched on " A+mB ":

B: be the center of circle with the contre electrode, clockwise or counterclockwise contre electrode and the ring electrode that becomes the bilateral symmetry of same straight line to distribute are with it switched on and be connected, be t hour the conduction time on each connects, on each connects during in the energising beginning, switch on and change polarity of electrode after t1 hour, continue to switch on t2 hour until setting-up time t, switch to next energising then and connect, until finishing once complete energising;

Wherein m is integer, and 1≤m≤4; For example m can be 1,2,3 or 4.

Wherein, in the method, can adopt above-mentioned step mode (4) to carry out electronic reparation, preferably, described step mode (4) is as follows:

(4). be that the mode of cycling element is switched on " A+nC ":

C: be the center of circle with the contre electrode, clockwise or counterclockwise contre electrode and the ring electrode that becomes the bilateral symmetry of same straight line to distribute are with it switched on and be connected, on connecting, each does not change polarity of electrode, and after reaching t3 hour conduction time, switching to next energising connects, until finishing once complete energising, changing polarity of electrode then, to carry out next each energising connect hours be t4 hour complete energising, so repeating each energising, to connect last conduction time be the complete energising of t3 and t4, until finishing the electronic reparation of soil;

Wherein n is integer, and 2≤n≤4, and finishes when switching to the complete energising of next C after C energising the change polarity of electrode; For example n can be 2,3 or 4.

At aforesaid way (1) or mode B: wherein described " t " was 2-8 hour, as 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours or 8 hours; " t1 " is 1-7.5 hour, for example is 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours or 7 hours; " t2 " is 0.5-4 hour, and as 0.5 hour, 1 hour, 1.5 hours, 2 hours, 2.5 hours, 3 hours, 3.5 hours or 4 hours, condition was t1+t2=t.

At aforesaid way (2) or mode C: described " t3 " is 1-4 hour, for example is 1 hour, 2 hours, 3 hours or 4 hours, during do not change polarity of electrode.Reach setting value conduction time after t3 hour, switch the next order that connects, continue energising t3 hour, until finishing a complete energising, namely during this complete energising, the polarity of contre electrode and both sides ring electrode does not change all the time.After finishing a complete power cycles, the Fang Jinhang electrode switches, and begin next complete energising, in this " next complete energising ", be t4 hour the conduction time that each energising connects, described " t4 " is 0.5-1 hour, for example can be 0.5 hour or 1 hour, after finishing a complete energising, carry out the complete energising that each energising was connected to t3 hour again, and then carry out the complete energising that each energising is connected to t4, so carry out the repetitive cycling of t3+t4 repeatedly, until finishing soil treatment.

At aforesaid way (3): described " A+mB " mode refers to switch on as cycling element with " A+mB ", its implication is at first with mode A switch on simultaneously certain hour such as 4-12 hour, switch on mode B then, after finishing once complete energising, carry out mode B energising again, after reaching m time with mode B energising, the side switches on mode A again, and then the mode B that carries out m time switches on ... so move in circles, handle until the electronic pollution of finishing soil.

At aforesaid way (4): described " A+nC " mode refers to switch on as cycling element with " A+nC ", its implication is at first with mode A switch on simultaneously certain hour such as 4-12 hour, switch on mode C then, finish once complete energising (i.e. when energising connects the position of getting back to initial contre electrode and the ring electrode of the bilateral symmetry distribution that becomes same straight line with it again, also namely finish a circumference circulation) after, carry out mode C energising again, after reaching n time with mode C energising, Fang Zaici switches on mode A, and then the mode B that carries out n time switches on ... so move in circles, handle until the electronic pollution of finishing soil, after wherein whenever finishing a complete cycle energising with mode C, change the polarity of contre electrode and ring electrode.

More specifically, in brief, aforesaid way (1) is the circulation of mode B, and aforesaid way (2) is the circulation of mode C.

Be example with Fig. 4, step mode for above-mentioned (1), (2), B or C, can adopt the energising of counterclockwise " 1-2-3-4 " shown in the figure to connect order, at first switch on to connecting order " 1 ", switch to then and connect order " 2 ", namely be two ring electrodes energisings that baseline is respectively 45 ° and 225 ° to contre electrode with the trunnion axis, and then switch on to connecting order " 3 " and " 4 ", thereby finish a complete cycle, and the power cycles that enters next " 1-2-3-4 " subsequently; Certainly, also can adopt the power-up sequence of " 1-4-3-2 " clockwise.This energising order and timing switching comprise the above-mentioned dual mode of mentioning (1) or (2).

Be example with mode A: be negative electrode with the contre electrode, all ring electrodes are anode and antianode and negative electrode were switched on 4-12 hour simultaneously.

Be example with mode B: for example when energising connects order for " 1 ", namely two ring electrodes on contre electrode and the horizontal plane are switched on, on energising connects, be t hour total conduction time, and t is 2-8 hour for example 6 hours, begins logical electrochronograph certainly, when energising t1 hour for example 4 hours the time, change polarity of electrode [namely changing the polarity of contre electrode and ring electrode], continue energising t2 hour for example 2 hours, reach total conduction time of t1 as 6 hours; The order of will switching on then switches to next order " 2 ", proceeds the conduction time of same way as and regularly switching, by that analogy, switches on according to the energising connection order of " 1-2-3-4 ".When always in this way B circulate when energising, be the step mode of optimal way (1).

Be example with mode C: be 1-4 hour described conduction time, for example when energising connects order and be " 1 ", namely two ring electrodes on contre electrode and the horizontal plane are switched on, conduction time be t3 hour as 2 hours, during do not change polarity of electrode.After reaching setting value conduction time, switching to order " 2 ", namely is two ring electrodes energisings that baseline is respectively 45 ° and 225 ° to contre electrode with the trunnion axis, continues energising t3 hour as 2 hours.By that analogy, switch on according to the energising connection order of " 1-2-3-4 ", finish a complete cycle.Carrying out electrode then switches, and carry out the complete energising of the next one " 1-2-3-4 ", in the complete energising of this next one, be t4 hour as 0.5 or 1 hour the conduction time that each energising connects, after finishing a complete energising, carry out the complete energising that each energising was connected to t3 hour again, and then carry out the complete energising that each energising is connected to t4, so carry out the repetitive cycling of t3+t4 repeatedly, until finishing soil treatment.When circulating energising with mode C, be the step mode of optimal way (2).

Energising order by novelty like this and electrode switch, and the performance of system has been stablized near advantageously rapid rising or the decline of the soil pH value control electrode, has greatly improved the clearance of pollutant simultaneously and has removed efficient.

Wherein, for the smooth running of described electrode control system, connect dc source to obtain the power source of different voltage gradients.

In the experimental technique of the two-dimentional inhomogeneous field experimental provision of use of the present invention repairing polluted soil, as preferred embodiment a kind of, be provided with ammeter between described electrode control system and the contre electrode, to show the current data that is applied, it typically is 1mA-1000mA, for example can be 1mA, 5mA, 10mA, 50mA, 100mA, 200mA, 300mA, 400mA, 500mA, 600mA, 700mA, 800mA, 900mA or 1000mA.。

In the experimental technique of the two-dimentional inhomogeneous field experimental provision of use of the present invention repairing polluted soil, described data collecting system links to each other with each probe.By described data collecting system, can gather the two-dimentional voltage data that all probe measurements are arrived, thereby for the operator selects and/or changes voltage direct data information is provided, generally speaking, in all step modes, it is 0.1V/cm-5V/cm that the voltage that applies should be the voltage gradient that makes in the soil, for example can be 0.1V/cm, 0.5V/cm, 1V/cm, 2V/cm, 3V/cm, 4V/cm or 5V/cm.

In the experimental technique of the two-dimentional inhomogeneous field experimental provision of use of the present invention repairing polluted soil, can in experimentation, continue to add in the soil any additives well known in the prior art or synergist, promote desorption, degraded or the various chemical reaction process in soil such as pollutant such as heavy metal, organic pollution etc. as in complexing agent, chelating agent, surfactant, cosolvent, oxidation/reducing agent, acid-base salt solution, cushioning liquid, the microorganism etc. one or more.This adding can be by the end of tube connector and total isocon, and namely three ports carry out, and can add at any time according to the pollutant removal situation.As a kind of exemplary exemplifying, for example can add one or more the combination in citric acid, acetic acid, lactic acid, EDTA (ethylenediamine tetra-acetic acid), NTA (nitrilotriacetic acid), DTPA (diethyl pentetic acid), EGTA (ethylene glycol diethyl ether ethylenediamine tetraacetic acid (EDTA)), organic phosphonate, cyclodextrin, ethanol, butylamine, clorox, hydrogen peroxide, sodium metabisulfite, salt compounded of iodine, hydrochloric acid or its salt, nitric acid or its salt, phosphoric acid or its salt, sulfuric acid or its salt, NaOH, ammonia or ammonium salt, organic matter degradation bacteria or its flora, the various organic wastewaters etc.

This adding can manually be carried out, for example can manually add needed additive or synergist, but as preferred embodiment a kind of, described two-dimentional inhomogeneous field experimental provision also comprises the liquid adding apparatus, described liquid adding apparatus can be realized the adding of desired additives or synergist, for example can be the container such as pipette, the buret etc. that have scale.

The beneficial effect of the inventive method is:

1. utilize contre electrode and the ring electrode of set-up mode novelty, and in soil, apply inhomogeneous field, make pollutant do the non-linear two dimensional migration, prevented that it from entering in the enclosed type hole, and can simulate the actual repair situation better, distribute by the two-dimentional voltage in the probe assay soil, can determine easily that voltage gradient distributes.

2. utilize peristaltic pump in the future the liquid of self-electrode reflux, can in and the acidity/alkalescence of electrode, prevent from pollutant in high pH value or hang down under the pH value precipitating, more be conducive to the removal of pollutant.

3. especially by the changeable different polarity of electrode of electrode control system, and because the novelty of electrode arrangement mode changes, strengthen contacting and reaction of pollutant and the soil liquid, and in and near the Acidity of Aikalinity of electrode, thereby saved energy consumption, kept the stability of a system.

As mentioned above, the invention provides a kind of novelty, can remove pollutant in soil (as heavy metal or organic pollution) or add additive in the soil to strengthen the electronic prosthetic device of pollutant removal, described device has multiple excellent characteristics, is suitable for very much the repair process of contaminated soil.

Description of drawings

In order to be illustrated more clearly in described apparatus and method of the present invention, the accompanying drawing of required use is done simple the introduction in will describing embodiment below, but apparently, the accompanying drawing that describes below only is some embodiments of the present invention, for those of ordinary skills, under the prerequisite of not paying creative work, can also obtain modified accompanying drawing similar with it according to these accompanying drawings.

Fig. 1 is the structural representation of device of the present invention.

Fig. 2 be device of the present invention for the vertical view of cylindrical soil sample groove.

Fig. 3 is the preparation of soil sample schematic diagram of device of the present invention.

Fig. 4 is the electrode control order schematic diagram of the cylindrical soil sample groove of being arranged in of device of the present invention.

Wherein, the corresponding relation of the elements/components of each numeral number and/or code name and device of the present invention is as follows:

1. cell body 2. top covers 3. bottoms

4. contre electrode 5. ring electrodes 6. probes

7. sealing ring 8. bolts 9. device for measuring volumetric flow of fluid

10. peristaltic pump 11. gas measurement devices 12. data collecting systems

13. electrode control system 14. dc sources 15. nuts

16. isocon 17. tube connectors 18. pyknosis top boards

19. pyknosis groove 20. liquid adding apparatus

The specific embodiment

With reference to the accompanying drawings following; described apparatus and method of the present invention are described in detail further and/or set forth; but should be appreciated that; the exemplary description that this just makes device of the present invention and method of operating thereof; it is intended that to explain/elaboration described device of the present invention and embodiment thereof; but not be used for limiting and/or restriction the present invention, more non-protection scope of the present invention is confined to this.

With reference to figure 1, described device of the present invention comprises soil sample groove, gas measurement device 11, liquid circulation and measurement mechanism, electrode control system 13 and data collecting system 12.Wherein, described soil sample groove comprises cell body 1, top cover 2, bottom 3, and is used for the fixedly bolt 8 of cell body 1, top cover 2, bottom 3, in order to strengthen sealing property, is being equipped with sealing ring 7 between top cover 2 and the cell body 1 and between bottom 3 and the cell body 1.

The opposite position of described top cover 2 and bottom 3 is provided with a plurality of nut (not shown), and one of them nut is positioned at the center, all the other nuts be positioned at this center nut around, and be symmetrical centre and distributing ringwise with described center nut.Corresponding described going up between the lower nut is provided with electrode, be contre electrode 4 and a plurality of ring electrode 5, electrode is hollow form, and the electrode tube wall is provided with equally distributed a plurality of aperture, when installing, electrode around it, is provided with leak-proof device (not shown), for example filter paper, filter cloth or filter screen etc.Also be evenly distributed with a plurality of probes 6 that extend into described soil sample groove inside on the top cover 2.

Described gas measurement device 11 is the graded tube that links to each other with the electrode upper end.

The circulation of described liquid and measurement mechanism comprise the tube connector 17 that links to each other with contre electrode 5 lower ends, the isocon 16 that links to each other with ring electrode 5 lower ends, the peristaltic pump 10 between tube connector, the device for measuring volumetric flow of fluid that links to each other with the end of the end of tube connector 17 and isocon 16.

Described electrode control system 13 links to each other with each electrode, and by dc source 14 powered operations.Between described electrode control system 13 and contre electrode 4, be provided with ammeter, thereby can detect the size of current in the soil.

Described data collecting system 12 links to each other with each probe 6, thereby can detect the voltage distribution gradient in the soil in real time.

Described device of the present invention also can comprise liquid adding apparatus 20, it can join additive, synergist or microorganism etc. in the threeway of tube connector or total isocon end, thereby by electrode 4 and 5 and the backflow of peristaltic pump enter into soil, under the inhomogeneous field effect, realize the efficient removal of pollutant.

With reference to figure 2, this figure is the vertical view of the soil sample groove of device of the present invention.Described cell body horizontal section is circular, is top cover on it, and fixes by a plurality of bolts 8.The center is contre electrode 4, is symmetrically distributed with a plurality of ring electrodes 5 around this center, is inserted with a plurality of equally distributed probes 6 on the top cover.In order to strengthen sealing property, between top cover and cell body, be provided with sealing ring 7.

With reference to figure 3, this figure is the preparation of soil sample schematic diagram of device of the present invention.When the soil sample of preparation contaminated soil, the soil sample groove to be inverted, the base plate of described top cover 2 during as the preparation of soil sample unscrewed the nut of all electrodes, and probe 6 turned on.Above cell body 1, place the pyknosis groove 19 identical with the cell body internal diameter, place than the smaller pyknosis plate 18 of described pyknosis groove 19 internal diameters pyknosis groove 19 tops, for example than the little 1-5mm of described pyknosis groove 19 internal diameters, thereby can closely enter into described pyknosis groove 19 inside, and compress the pollution mud of pouring into, have a plurality of apertures on the described pyknosis plate 18 to discharge the water that voltage supply is overflowed when tight.

When the preparation of soil sample, mud slowly is poured in the described cell body 1, mix, on mud, lay filter screen or filter cloth then, place pyknosis plate 17 then, apply external force and press pyknosis plate 17 downwards, thereby mud is carried out fixed compression.In compression process, the water in the mud can flow out from the slit of electrode hole, probe aperture and the aperture on the pyknosis plate 18.

When compression finishes, finish fixed after, take pyknosis groove 19 and pyknosis plate 18 away, and remove filter screen or the filter cloth of placing, and remove unnecessary soil (when not unnecessary, then need not remove) suitably according to the volume of soil sample groove.Put described bottom 3 then, tight a bolt 8 and probe 6, and tighten the nut of electrode.Then the soil sample groove is overturn, thereby finished the preparation of soil sample.

With reference to figure 4, this figure is the electrode control order schematic diagram of device of the present invention.Provide to this illustrated example the electrode control order of a kind of as above-mentioned mode (1) or (2) or B or C, by the control of electrode control system, can realize timing energising and outage to contre electrode and ring electrode, and the conversion on the polarity.For example, can adopt the energising of counterclockwise " 1-2-3-4 " shown in the figure to connect order, also can adopt the power-up sequence of " 1-4-3-2 " clockwise.Connect order and polarity of electrode control mode by this energising, just can apply inhomogeneous field to contaminated soil, be very beneficial for removing of pollutant, and can conserve energy consumption.

The invention will be further described below in conjunction with instantiation, but should be appreciated that, these embodiment only are used for the usefulness exemplify, and be used for restriction and intention restriction range of application of the present invention and embodiment absolutely not, more non-protection scope of the present invention is confined to this.

Embodiment 1: for the test that removes of heavy metal Cd

Preparation of soil sample method with reference to figure 3, having prepared Cd content is the test soil sample of 300mg/kg, described soil sample groove is of a size of 14cm (length) * 14cm (wide) * 5cm (height), be contre electrode in the center that is the foursquare inscribed circle of cross section wherein, a peripheral regularly arranged loop electrode, these ring electrodes are symmetrical centre and evenly distributed with the contre electrode, and with soil sample groove edge distance be 1cm.

Described electrode is the form of hollow, and the electrode tube wall is provided with the aperture that the aperture is 3mm.Described electrode periphery is provided with filter cloth, enters into hollow electrode to prevent soil.Between the top cover and cell body of described soil sample groove, be equipped with the acrylonitrile-butadiene rubber sealing ring between bottom and the cell body, to keep excellent sealing performance, determine voltage gradient for the voltage of measuring the diverse location place, be inserted with many probes on the top cover of described soil sample groove, its length is 2/3.

" A+B " energising that circulates as follows:

A: be negative electrode with the contre electrode, ring electrode is anode and antianode and negative electrode were switched on 4 hours simultaneously;

B: be the center of circle with the contre electrode, counterclockwise contre electrode is connected energising in turn with the ring electrode that the bilateral symmetry that becomes same straight line with it distributes, connect energising 2 hours at each, per 1 hour change one-time electrode polarity during the energising, namely before switching to next the connection, change polarity of electrode 2 times, until finishing once complete energising.

After finishing one " A+B ", carry out the next one " A+B " again ... until finishing whole soil energising repair process.

The common electric treatment of this electronic repair process 510 hours, wherein 0-160 hour energising voltage is that 24V, 160-190 hour energising voltage is that 20V, 190-204 hour energising voltage is that 15V, 204-260 hour energising voltage is that 12V, 260-510 hour energising voltage is 24V.Though wherein exist the endpoint value of coincidence these conduction times, but the smooth implementation of influence technique scheme and just understanding was not example with 160 hours for example, when the energising beginning to arrive just 160 hours during energising voltage be 24V, and when reaching 160 hours, changing voltage immediately is 20V.All the other overlap endpoint value and have identical meanings.

In galvanization, by the liquid adding apparatus, add the mixed aqueous solution of citric acid and acetic acid in the ring electrode at three ports of total isocon end, wherein citric acid concentration is that 3g/L and acetic acid concentration are 5.5g/L, three ports by the tube connector end add the mixed aqueous solution of citric acid and acetic acid in the contre electrode, wherein citric acid concentration is that 3g/L and acetic acid concentration are 6.1g/L, these two kinds of mixed aqueous solutions pH be 2.0.When normal operation, in by peristaltic pump and the pH value of anode and negative electrode, make it to remain between the 3-5, so that near male or female, do not produce heavy metal precipitation, simultaneously, discharge by remaining electrode trickle being entered device for measuring volumetric flow of fluid, to reach the purpose of removing Cd ion rehabilitating soil.

After operation finishes, measure the average Cd ion concentration in the soil sample, the 300mg/kg when finding its concentration by beginning is reduced to 10mg/kg, and removal efficiency is 96.67%.

Embodiment 2: for the test that removes of heavy metal Cd

Outside switching on divided by following mode, to have implemented embodiment 2 with the identical of embodiment 1.

" A+2B " energising that circulates as follows:

A: be negative electrode with the contre electrode, ring electrode is anode and antianode and negative electrode were switched on 12 hours simultaneously;

B: be the center of circle with the contre electrode, counterclockwise contre electrode is connected energising in turn with the ring electrode that the bilateral symmetry that becomes same straight line with it distributes, connect energising 1.5 hours at each, per 0.5 hour change one-time electrode polarity during the energising, namely before switching to next the connection, change polarity of electrode 3 times, until finishing once complete energising.

After operation finishes, measure the average Cd ion concentration in the soil sample, the 300mg/kg when finding its concentration by beginning is reduced to 12.5mg/kg, and removal efficiency is 95.83%.

Embodiment 3: for the test that removes of heavy metal Cd

Outside switching on divided by following mode, to have implemented embodiment 3 with the identical of embodiment 1.

" A+4B " energising that circulates as follows:

B: be the center of circle with the contre electrode, counterclockwise contre electrode is connected energising in turn with the ring electrode that the bilateral symmetry that becomes same straight line with it distributes, connect energising 1 hour at each, per 0.5 hour change one-time electrode polarity during the energising, namely before switching to next the connection, change polarity of electrode 2 times, until finishing once complete energising.

After operation finishes, measure the average Cd ion concentration in the soil sample, the 300mg/kg when finding its concentration by beginning is reduced to 13mg/kg, and removal efficiency is 95.67%.

Embodiment 4: for the test that removes of heavy metal Cd

Except according to the following step mode, to have carried out the present embodiment operation with the same way as of embodiment 1.

" A+2C " energising that circulates as follows:

C: be the center of circle with the contre electrode, clockwise or counterclockwise contre electrode and the ring electrode that becomes the bilateral symmetry of same straight line to distribute are with it switched on and be connected, on each connects, do not change polarity of electrode from start to finish, switch on after 1 hour, switch to the next order that connects, until finishing once complete energising.

After operation finishes, measure the average Cd ion concentration in the soil sample, the 300mg/kg when finding its concentration by beginning is reduced to 20.1mg/kg, and removal efficiency is 93.33%.

Embodiment 5: for the test that removes of heavy metal Cd

" A+3C " energising that circulates as follows:

A: be negative electrode with the contre electrode, ring electrode is anode and antianode and negative electrode were switched on 8 hours simultaneously;

C: be the center of circle with the contre electrode, clockwise or counterclockwise contre electrode and the ring electrode that becomes the bilateral symmetry of same straight line to distribute are with it switched on and be connected, on each connects, do not change polarity of electrode from start to finish, switch on after 3 hours, switch to the next order that connects, until finishing once complete energising.

After operation finishes, measure the average Cd ion concentration in the soil sample, the 300mg/kg when finding its concentration by beginning is reduced to 22.9mg/kg, and removal efficiency is 92.37%.

Embodiment 6: for the test that removes of heavy metal Cd

" A+4C " energising that circulates as follows:

C: be the center of circle with the contre electrode, clockwise or counterclockwise contre electrode and the ring electrode that becomes the bilateral symmetry of same straight line to distribute are with it switched on and be connected, on each connects, do not change polarity of electrode from start to finish, switch on after 4 hours, switch to the next order that connects, until finishing once complete energising.

After operation finishes, measure the average Cd ion concentration in the soil sample, the 300mg/kg when finding its concentration by beginning is reduced to 21.4mg/kg, and removal efficiency is 92.87%.

Embodiment 7-9: for the test that removes of heavy metal Cd

Except respectively according to the following step mode, respectively with the embodiment 7-9 in implementing with the same way as of embodiment 1.

(1) energising circulates as follows:

The step mode of embodiment 7 (1): be the center of circle with the contre electrode, counterclockwise contre electrode is connected energising in turn with the ring electrode that the bilateral symmetry that becomes same straight line with it distributes, connect energising 2 hours at each, be negative electrode with the contre electrode earlier during the energising, ring electrode is anodal closure 1.5 hours, changing one-time electrode polarity energising 0.5 hour then, namely is negative electrode with the contre electrode, and ring electrode is anodal closure.Switch to and switched in the same way 2 hours next the connection, until finishing once complete energising, repetitive cycling like this is until finishing soil treatment.

The step mode of embodiment 8 (1): be the center of circle with the contre electrode, counterclockwise contre electrode is connected energising in turn with the ring electrode that the bilateral symmetry that becomes same straight line with it distributes, connect energising 4 hours at each, be negative electrode with the contre electrode earlier during the energising, ring electrode is anodal closure 3 hours, changing one-time electrode polarity energising 1 hour then, namely is anode with the contre electrode, and ring electrode is cathodal closing.Switch to and switched in the same way 4 hours next the connection, until finishing once complete energising, repetitive cycling like this is until finishing soil treatment.

The step mode of embodiment 9 (1): be the center of circle with the contre electrode, counterclockwise contre electrode is connected energising in turn with the ring electrode that the bilateral symmetry that becomes same straight line with it distributes, connect energising 8 hours at each, be negative electrode with the contre electrode earlier during the energising, ring electrode is anodal closure 6 hours, changing one-time electrode polarity energising 2 hours then, namely is anode with the contre electrode, and ring electrode is cathodal closing.Switch to and switched in the same way 8 hours next the connection, until finishing once complete energising, repetitive cycling like this is until finishing soil treatment.

After operation finishes, measure the average Cd ion concentration in the embodiment 7-9 soil sample respectively, find that the Cd removal efficiency is 90.1%-91.4%.

Embodiment 10-12: for the test that removes of heavy metal Cd

Except respectively according to the following step mode, respectively with the embodiment 10-12 in implementing with the same way as of embodiment 1.

(2) energising circulates as follows:

The step mode of embodiment 10 (2): be the center of circle with the contre electrode, clockwise or counterclockwise contre electrode and the ring electrode that becomes the bilateral symmetry of same straight line to distribute with it being switched on is connected.Be negative electrode with the contre electrode earlier, ring electrode is that anode connects energising 1 hour at each, do not change polarity of electrode from start to finish, switch to the next order that connects after reaching 1 hour, after finishing a complete energising, changing polarity of electrode and carry out next complete power cycles, namely is anode with the contre electrode, and ring electrode is that negative electrode connects energising 0.5 hour at each.So move in circles, until the energising total time that reaches 510 hours, finish the electronic repair process of final soil.

The step mode of embodiment 11 (2): be the center of circle with the contre electrode, clockwise or counterclockwise contre electrode and the ring electrode that becomes the bilateral symmetry of same straight line to distribute with it being switched on is connected.Be negative electrode with the contre electrode earlier, ring electrode is that anode connects energising 2.5 hours at each, do not change polarity of electrode from start to finish, switch to the next order that connects after reaching 2.5 hours, after finishing a complete energising, changing polarity of electrode and carry out next complete power cycles, namely is anode with the contre electrode, and ring electrode is that negative electrode connects energising 0.5 hour at each.So move in circles, until the energising total time that reaches 510 hours, finish the electronic repair process of final soil.

The step mode of embodiment 12 (2): be the center of circle with the contre electrode, clockwise or counterclockwise contre electrode and the ring electrode that becomes the bilateral symmetry of same straight line to distribute with it being switched on is connected.Be negative electrode with the contre electrode earlier, ring electrode is that anode connects energising 4 hours at each, do not change polarity of electrode from start to finish, switch to the next order that connects after reaching 4 hours, after finishing a complete energising, changing polarity of electrode and carry out next complete power cycles, namely is anode with the contre electrode, and ring electrode is that negative electrode connects energising 1 hour at each.So move in circles, until the energising total time that reaches 510 hours, finish the electronic repair process of final soil.

After operation finishes, measure the average Cd ion concentration in the embodiment 10-12 soil sample respectively, find that the Cd removal efficiency is 90.1%-91.2%.

Embodiment 13: for the test that removes of heavy metal Zn

Except heavy metal being replaced with the Zn ion, test with method similarly to Example 1.

After operation finishes, measure the average Zn ion concentration in the soil sample, the 300mg/kg when finding its concentration by beginning is reduced to 12mg/kg, and removal efficiency is 96.00%.

Embodiment 14: the degraded for oil removes test

With reference to the preparation of soil sample method of figure 3, use the same apparatus of embodiment 1, having prepared oil content is the test soil sample of 50g/kg.

With the energising that circulates of following " A+2B " mode:

B: be the center of circle with the contre electrode, counterclockwise contre electrode is connected energising in turn with the ring electrode that the bilateral symmetry that becomes same straight line with it distributes, connect energising 2 hours at each, per 0.5 hour change one-time electrode polarity during the energising, namely before switching to next the connection, change polarity of electrode 4 times, until finishing once complete energising.

After finishing one " A+B ", carry out the next one " A+B " again ... until finishing whole soil energising repair process.The voltage of wherein switching on is 24V, common electric 900 hours.

In the galvanization, three ports by total isocon and tube connector end add oil degradation flora and known any nutritive solution in ring electrode respectively, and for example this nutritive solution can be NH ₄NO ₃And KH ₂PO ₄Mixed aqueous solution, both concentration is 0.1mol/L, the pH of this mixture is 7.0, when normal operation, by peristaltic pump in and the pH value of anode and negative electrode, make it to control between 6-7.

After operation finishes, measure the average oil content in the soil sample, the 50g/kg when finding its concentration by beginning is reduced to 17g/kg, and removal efficiency is 66.70%.

Embodiment 15: the degraded for oil removes test

Except according to the following step mode, to have carried out the present embodiment operation with the same way as of embodiment 14.

" A+2C " energising that circulates as follows:

After operation finishes, measure the average oil content in the soil sample, the 50g/kg when finding its concentration by beginning is reduced to 14g/kg, and removal efficiency is 72.00%.

Embodiment 16: the degraded for oil removes test

Switch on according to mode (1): be the center of circle with the contre electrode, counterclockwise contre electrode is connected energising in turn with the ring electrode that the bilateral symmetry that becomes same straight line with it distributes, connect energising 2 hours at each, per 0.5 hour change one-time electrode polarity during the energising, namely before switching to next the connection, change polarity of electrode 4 times, until finishing once complete energising.So move in circles, until the energising total time that reaches 900 hours, finish the electronic repair process of final soil.

After operation finishes, measure the average oil content in the soil sample, the 50g/kg when finding its concentration by beginning is reduced to 15g/kg, and removal efficiency is 70.00%.

Embodiment 17: the degraded for oil removes test

Switch on according to mode (2): be the center of circle with the contre electrode, clockwise or counterclockwise contre electrode and the ring electrode that becomes the bilateral symmetry of same straight line to distribute are with it switched on and be connected, connect energising 2 hours at each, do not change polarity of electrode from start to finish, switch to the next order that connects after reaching 2 hours, after finishing a complete energising, change polarity of electrode and carry out next complete power cycles, so move in circles, until the energising total time that reaches 900 hours, finish the electronic repair process of final soil.

After operation finishes, measure the average oil content in the soil sample, the 50g/kg when finding its concentration by beginning is reduced to 9.15g/kg, and removal efficiency is 81.7%.

Comparative Examples 1: for the test that removes of heavy metal Cd

Preparation of soil sample method with reference to figure 3, having prepared Cd content is the test soil sample of 282mg/kg, described soil sample groove is of a size of 14cm (length) * 14cm (wide) * 5cm (height), in the foursquare relative both sides of cross section 3 electrodes that are same as electrode of the present invention are set respectively, the corresponding electrode of both sides is at a distance of 12cm, and namely every electrode distance soil sample groove edge is 1cm.

Described electrode is the form of hollow, and the electrode tube wall is provided with the aperture that the aperture is 3mm.Described electrode periphery is provided with filter cloth, enters into hollow electrode to prevent soil.Between the top cover and cell body of described soil sample groove, be equipped with the acrylonitrile-butadiene rubber sealing ring between bottom and the cell body, to keep excellent sealing performance, determine voltage gradient for the voltage of measuring the diverse location place, be inserted with many probes on the top cover of described soil sample groove, its length is 2/3 of electrode.

Two lateral electrodes are switched on, common electric treatment 510 hours, wherein 0-160 hour energising voltage is that 24V, 160-190 hour energising voltage is that 20V, 190-204 hour energising voltage is that 15V, 204-260 hour energising voltage is that 12V, 260-510 hour energising voltage is 24V.

In galvanization, by the liquid adding apparatus, add the mixed aqueous solution of citric acid and acetic acid in this lateral electrode at three ports of the total isocon end that connects a lateral electrode, wherein citric acid concentration is that 3g/L and acetic acid concentration are 5.5g/L.To this mixed aqueous solution that adds citric acid and acetic acid in addition in lateral electrode, wherein citric acid concentration is that 3g/L and acetic acid concentration are 6.1g/L at three ports of the tube connector end that connects other lateral electrode, these two kinds of mixed aqueous solutions pH be 2.0.When normal operation, in by the peristaltic pump that connects total isocon and tube connector and the pH value of anode and negative electrode, make it to remain between the 3-5, so that near male or female, do not produce heavy metal precipitation, simultaneously, discharge by remaining electrode trickle being entered device for measuring volumetric flow of fluid, to reach the purpose of removing Cd ion rehabilitating soil.After operation finishes, measure the average Cd ion concentration in the soil sample, the 282mg/kg when finding its concentration by beginning is reduced to 43.15mg/kg, and removal efficiency is 84.7%.

Comparative Examples 2: for the test that removes of heavy metal Cd

Be negative electrode with the contre electrode, ring electrode is that anode was switched on 510 hours simultaneously, namely except not interting the mode B energising, removes test to have carried out heavy metal Cd with the same way as of embodiment 1.

After operation finishes, measure the average Cd ion concentration in the soil sample, the 300mg/kg when finding its concentration by beginning is reduced to 38.93mg/kg, and removal efficiency is 87.02%.

Comparative Examples 3: the degraded for oil removes test

Except the pH value that contre electrode and a plurality of ring electrode is replaced with two battery lead plates that are arranged in parallel, regulates anode and negative electrode by manual type makes it to control between 6-7, and two electrode plate were changed outside the one-time electrode polarity every 2 hours, to operate with the same way as of embodiment 14, the degraded removal effect for oil is put in test.

After operation finishes, measure the average oil content in the soil sample, the 50g/kg when finding its concentration by beginning is reduced to 20.48g/kg, and removal efficiency only is 59.04%.

Comparative Examples 4: the degraded for oil removes test

Except the polarity that does not change contre electrode and ring electrode from start to finish, (be that contre electrode is negative electrode for anode, ring electrode always always, perhaps contre electrode is that negative electrode, ring electrode are anode always always), to operate with the same way as of embodiment 14, the degraded removal effect for oil is put in test.

After operation finishes, measure the average oil content in the soil sample, the 50g/kg when finding its concentration by beginning is reduced to 24.26g/kg, and removal efficiency only is 51.48%.

Can be found out apparently by above-mentioned all embodiment and Comparative Examples, when adopting device of the present invention and soil remediation method, it has good clearance to heavy metal and organic pollution, wherein with regard to the difference of step mode and for the heavy metal removal effect that produces, " A+mB "〉" A+nC "〉" (1) or (2) ", and when removing organic pollution, then " (2) " clearance is the highest, and " A+mB " is minimum.

But no matter be for heavy metal or organic pollution, method of the present invention all will be better than the clearance of any prior art significantly, this has proved that apparatus of the present invention have more excellent pollutant removing effect than similar device of the prior art, and when adopting same apparatus of the present invention and same procedure, the pollutant removing effect has obtained further, beyond thought raising and improvement, and this has proved that further apparatus of the present invention and method are for excellent effect and the good prospects for application of electric restoring polluted soil.

Although for example with the purpose of description, and introduced structure and processing procedure shown in above-mentioned embodiment of the present invention and the accompanying drawing.But these are not to be detailed description, scope of the present invention can not be confined to this.For a person skilled in the art, can make numerous modifications and variations to above-mentioned embodiment of the present invention, and these all modifications and/or change all are included in as within the claim of the present invention institute restricted portion, do not break away from the scope and spirit of the present invention that claim as described limits.

Claims

1. experimental technique that uses two-dimentional inhomogeneous field experimental provision repairing polluted soil, it is characterized in that: described device comprises soil sample groove, gas measurement device, liquid circulation and measurement mechanism, electrode control system and data collecting system;

Described electrode control system links to each other with each electrode;

Described data collecting system links to each other with each probe;

(3). be that the mode of cycling element is switched on " A+mB ":

Wherein m is integer, and 1≤m≤4;

(4). be that the mode of cycling element is switched on " A+nC ":

2. the experimental technique of the two-dimentional inhomogeneous field experimental provision of use as claimed in claim 1 repairing polluted soil is characterized in that: adopt step mode (1) to carry out electronic reparation, described step mode (1) is as follows:

(1). be the center of circle with the contre electrode, clockwise or counterclockwise contre electrode and the ring electrode that becomes the bilateral symmetry of same straight line to distribute are with it switched on and be connected, be t hour the conduction time on each connects, on each connects during in the energising beginning, switching on changed polarity of electrode after t1 hour, continued to switch on t2 hour until setting-up time t, switched to next energising then and connected, until finishing once complete energising, so repeat to finish the electronic reparation of soil;

Wherein, described " t " is 2-8 hour, and " t1 " is 1-7.5 hour, and " t2 " is 0.5-4 hour.

3. the experimental technique of the two-dimentional inhomogeneous field experimental provision of use as claimed in claim 1 repairing polluted soil is characterized in that: adopt step mode (2) to carry out electronic reparation, described step mode (2) is as follows:

(2). be the center of circle with the contre electrode, clockwise or counterclockwise contre electrode and the ring electrode that becomes the bilateral symmetry of same straight line to distribute are with it switched on and be connected, on connecting, each does not change polarity of electrode, and after reaching t3 hour conduction time, switching to next energising connects, until finishing once complete energising, changing polarity of electrode then, to carry out next each energising connect hours be t4 hour complete energising, so repeating each energising, to connect last conduction time be the complete energising of t3 and t4, until finishing the electronic reparation of soil;

Wherein, described " t3 " is 1-4 hour, and described " t4 " is 0.5-1 hour.

4. the experimental technique of the two-dimentional inhomogeneous field experimental provision of use as claimed in claim 1 repairing polluted soil is characterized in that: adopt step mode (3) to carry out electronic reparation, described step mode (3) is as follows:

(3). be that the mode of cycling element is switched on " A+mB ":

B: be the center of circle with the contre electrode, clockwise or counterclockwise contre electrode and the ring electrode that becomes the bilateral symmetry of same straight line to distribute are with it switched on and be connected, be t hour the conduction time on each connects, on connecting, each begins during in energising, switch on and change polarity of electrode after t1 hour, continue to switch on t2 hour until setting-up time t, switch to next energising then and connect, until finishing once complete energising;

Wherein, m is integer, and 1≤m≤4; Described " t " is 2-8 hour, and " t1 " is 1-7.5 hour, and " t2 " is 0.5-4 hour.

5. the experimental technique of the two-dimentional inhomogeneous field experimental provision of use as claimed in claim 1 repairing polluted soil is characterized in that: adopt step mode (4) to carry out electronic reparation, described step mode (4) is as follows:

(4). be that the mode of cycling element is switched on " A+nC ":

Wherein, n is integer, and 2≤n≤4, and finishes when switching to the complete energising of next C after C energising the change polarity of electrode; Described " t3 " is 1-4 hour, and described " t4 " is 0.5-1 hour.

6. as the experimental technique of the two-dimentional inhomogeneous field experimental provision of each described use of claim 1-5 repairing polluted soil, it is characterized in that: in described step mode A, be 4-12 hour conduction time.

7. as the experimental technique of the two-dimentional inhomogeneous field experimental provision of each described use of claim 1-6 repairing polluted soil, it is characterized in that: between described top cover and the cell body, be equipped with sealing ring between bottom and the cell body.

8. as the experimental technique of the two-dimentional inhomogeneous field experimental provision of each described use of claim 1-7 repairing polluted soil, it is characterized in that: described sealing ring is acrylonitrile-butadiene rubber, fluorubber, silicon rubber or ACM.

9. as the experimental technique of the two-dimentional inhomogeneous field experimental provision of each described use of claim 1-8 repairing polluted soil, it is characterized in that: the length of described probe is the 1/3-2/3 of electrode length.

10. as the experimental technique of the two-dimentional inhomogeneous field experimental provision of the described use of claim 1-9 repairing polluted soil, it is characterized in that: described device also comprises the liquid adding apparatus, adds in complexing agent, chelating agent, surfactant, acid-base salt solution, cushioning liquid or the microorganism one or more in the soil by this device.