TWI249441B - Innovative electrokinetic system and method for remediation of heavy metal-contaminated soil - Google Patents

Abstract

An innovative electrokinetic remediation system and method which with many advantages for heavy metal contaminated soil had been developed. Open type design of electrokinetic reactor was convenient for putting and removing more contaminated soil comparing with those of closed types. Different inner small tanks were designed as soil tank, desorption/sedimentation tank, or buffer tank and available for inserting into electrokinetic reactor, adapting voltage gradient, soil amount, and cationic/anionic buffer of soil. In this electrokinetic reactor, acid chemical agents, heavy metal chelates, or anionic surfactants were needed no more but water. Consequently, cost reduction was shown in both chemical reagent and applied current. One of the nice innovative concept/design is setting the soil tank closed to the Anode area in which lots of hydrogen ions were generated by hydrolysis. Acid front moving toward the Cathode will pass through soil tank and strongly enhance desorption or/and dissolution of metal pollutants from contaminated soil. In addition, ionic migration and electroosmosis that occurred in electrokinetic reactor were attributed to the three major contributions of soil remediation. This innovative method had been verified in several metal-contaminated soils and shown many advantages such as operational convenience, time consumption, and cost reduction etc. The soil, after remediation, could be putted back to the original place or be used as normal soil since residual metals in soil were measured below EPA criteria.

Description

1249441 V. INSTRUCTIONS (1) - [Technical field to which the invention pertains] The present invention relates to the field of soil pollution remediation technology for environmental engineering, and more particularly to a system for removing harmful heavy metals from heavy metal contaminated soil by electrodynamic method And method. [Prior Art] 1 · Reaction in the electrodynamic remediation system and system: The electrodynamic rectification system is to place two electrodes between the contaminated soil, and to pass a direct current or a krypton current to form a reaction electric field between the two electrodes. The soil pore water first generates 〇2(g) and H2(g) at the anode and cathode by electrolysis. The reaction formula is (Aishawabkeh and Acar, 1992): (1) (2) 2H20 — 〇2(g) + + heart 2H20 + 2e_ — H2(g) + 20H-

Eo = -1· 229V (anode) Eo = -0· 828V (cathode) The above reaction is caused by the formation of H+ and OH-, causing the pH near the anode to decrease to about 3, and the pH near the cathode to rise to about 11. However, the overall system is affected by electric field gradients, concentration ladders, and electrical properties, which gradually produce several flow phenomena. First, since the ion mobility of Η OH ions in the electric field is much larger than all other anions and cations (about 3-7 times), the mobility of H+ ions is the first of all ions (about 1.8 times the OH-ion). (Acarand Alshawabkeh, 1 993). Because of this, the H+ ions formed near the anode form an "acid front" that moves toward the cathode, and the cathode produces an "initial front" of ions.

Page 8 1249441 V. INSTRUCTIONS (2) Also moving toward the anode. This acidic front is affected by the "buffer capacity" of the soil system. If the buffering capacity is low, the acidic front is easily exchanged or dissolved with the heavy metal contaminants originally adsorbed or precipitated on the surface of the soil colloid. The heavy metal is desorbed or eluted and moved to the cathode in a hydrated or misaligned form. The ion movement under the action of these electric field gradients is called "ionic migration". In addition, the soil pore fluid between the charged soil particles will produce "electroosmosis" due to the electric field gradient of the electromotive force, which will cause the ionic and non-ionic substances in the soil pores to follow the electroosmotic flow. mobile. But before the heavy metal cations move to the cathode, they will meet the "basic front" flowing to the anode, and the precipitate will form a heavy metal hydroxide (M ( OH)n ( s )), which will cause the middle to be treated. The heavy metal pollutants in the soil can not be removed, which is equivalent to the practice of redistributing heavy metal pollutants in the soil. That is to say, many electric power remediation of heavy metal contaminated soil can only remove the soil near the anode, but the overall effect is not good. In addition to the above effects, the species in the liquid phase system of electrodynamic rectification will also have a "dif fusi〇n" phenomenon due to the concentration gradient. In addition, if there is a charged colloid in the liquid phase, it will also be affected by the electric field. "electrophoresis" phenomenon. On the whole, the original physicochemical properties of the soil are very complicated (the soil parent material is the spring and secondary minerals of different types/properties of primary minerals, and the soil also has different porosity, organic matter, surface electrical properties, etc.) The types and species of heavy metal pollutants on the outside are often different, so the electric power system is a complex and interactive system, including: (丨) the constant voltage or constant current applied, and the ion migration and electricity caused by the electric field. penetration,

Page 9 1249441 V. Description of invention (3) Electrophoresis, oxidation, reduction, polarization, etc.; (2) Soil and heavy metal species/species, and microscopic adsorption, desorption, precipitation, dissolution and other reactions on the inner and outer surfaces of the soil; (3) Soil porosity, soil electrical properties, flow of pore fluids, etc.; (4) Additional human remediation practices, such as the application of high-pressure water bodies in closed reaction tanks, and the addition of chemical agents that facilitate the desorption of pollutants. 2. Research and technology of foreign electric power remediation: Research on electrodynamic remediation of soil abroad. The research group of Prof. Acar from Ljuana State University (LSU) is the focus of the study on soil electrodynamic remediation procedures. The basic phenomenon and the removal of heavy metal pollutants (such as pb, Cr, Cd, etc.), as well as the electrodynamic remediation of organic pollutants (such as phenol) and surfactant desorption TNT; in addition, Professor Acar also implements the United States The pi1〇t plant experiment commissioned by the Environmental Protection Agency (Acar and H aider, 1 9 9 Ο, A careta 1 ·, 9 9 2 ; A careta 1 ·, 1 9 9 3 ; Acar et al· , 1994; Acar et al., 1995; Acar and Alshawabkeh, 1996a; Acar and Alshawabkeh, 1996b). Unfortunately, Professor Acar died in a car accident in May 1996, following Professor Acar's current teaching of A1 shawabkeh at Northeastern University, and subsequent follow-up studies (Alshawabkeh, 1997; Alshawabkeh et al., 1999). In addition, Professor Probste in's research group at the Massachusetts Institute of Technology (MIT) focused on the removal of organic matter (such as acetic acid, phenols, etc.) in kaolin, and in the capillary model (capillary model) in consideration of the reaction of major soil species. Simulated electroosmotic flow and its concentration distribution; also discussed the removal of EDTA to form heavy metal complexes (Renaud and Probstein, 1 987; Shapiro et al., 1989; Shapiro and Probstein, 1993;

Page 10 1249441 V. Description of invention (4)

Probstein and Hicks, 1993). In addition to the above, there are also Tompson et a 1 · (1 994), Weng et a 1 (1 9 94), Pamukcu et al (1 997), Reddy and Parupudi (1 997), Reddy and Chinthamreddy (1999). Kim et al (2002), Chen et al 1. (2002), Musso (2003), Vereda-Alonso et al (2004), etc., performing bench-scale electrodynamic remediation of heavy metal pollution Soil research. 3. Domestic electric power remediation research and technology: China's electric power remediation soil research began in 1993-94, Hong Yujia (1993 '1997) used 10 mM copper sulfate to synthesize contaminated quartz sand, kaolin and red loam, and The view of mass and charge balance explores the changes in the interior of the reaction cell during the electrodynamic reaction. In 1998, Hong Yujia et al. artificially synthesized 1 mM Cr(III), Cr(VI), Pb, Cd contaminated quartz sand and kaolin. Under the unadded solution and water head, the removal rate of heavy metals in quartz sand reached five days. More than 8〇%, and the removal rate of Pb and cd in kaolin was lower, which was 27% and 63%, respectively.

After Cr(VI) is reduced to Cr(III), it is difficult to remove. In 1999, Hong Yujia et al. further explored the two-dimensional concentration distribution of cadmium nitrate dissociation under electrokinetic action. Yan Xicheng (I"4) firstly discussed the artificially synthesized lead 2,23〇— 4 560 rhyme soil under constant current and constant voltage, and the removal rates were about 8% and 19% respectively. The main cause is that the soil near the cathode is low in water, and the Pb and 0Η-inspective fronts form a metal shoal. The method is to add NaW ΝΜΡ〇4 to the cathode and raise the anode head. For: 丄' into lead-containing 1,000 mg/kg kaolin The removal rate is 96% 1994).

Page 11 1249441 V. Description of invention (5) · Yang Jinzhong (1996) prepared 1, 2 mg/kg of Pb-containing soil with sloping loam, and added acetic acid, citric acid and EDTA to the anode tank, respectively. It is 5 3%, 28.8%, and 11%. It is obvious that the binding strength of Pb to the actual soil is strong and it is difficult to remove. Yang Jinzhong et al. (1998, 1999, 2000a, 2000b, 2001) continued to rectify phenol, tetrachlorophenol, trichloroethylene (TCE) and other organic contaminated soils by electrodynamic-Fenton method and electrodynamics _ jr ent ο η The method combines biological decomposition to treat penta-phenol. In addition, Yang Jinzhong et al. (19 9 9) prepared soil containing Cu, Pb about 100-1, 〇〇〇mg/kg with loamy sand and sandy loam, and combined with ion exchange in 2 days. Under the operation of resin or adding citric acid and acetic acid, the cu removal rate is about 28-87%, and the Pb removal rate is about 4-61%. Yang Jinzhong et al. (200 2 ) used electrokinetic method-Fenton method-catalytic iron powder wall combination technology to remediate soil contaminated by bismuth, bismuth, 2, 2-tetraethane (TeCA), at h2〇2 concentration 2 %, iron powder 0.2wt%, 20 days of operation, TeCA total destruction removal rate can reach about 70%. Yang Jinzhong and Chen Yuesheng (2〇〇2) used the sandbox experiment to explore the related parameters, electric field and pollutant distribution changes during the treatment of contaminated soil by electrodynamic method. Yang Jinzhong et al. (20 03) used the nano zero-valent iron powder wall combined with the electrodynamic method to carry out underground nitrate pollution remediation. Weng Zhuyu (1 997) prepared cadmium and lead 250, 500 mg/kg soil in sandy loam. After adding acetic acid, EDTA, ρΗ 4·5 artificial acid rain and raising the anode head, the removal rate was over 92%. Weng Zhihuang et al. (1 997) and electro-dynamic remediation of sludge from industrial areas containing various heavy metals yielded a removal efficiency of 19-8(10) and a high removal rate of heavy metals at a back concentration. Later, Weng Zhihuang and others (1998, 1999) changed to a fine a, 乂 electric power method for phenol, di-gas phenol, three-gas hope, four-gas and other ages, right-handed, -# shell organic 5 soil Bad remediation research, increasing voltage

1249441

Fifth, the invention description (6) slope down to 2 V / c m or more can be clearly _ quite in the mantle η people +

The same person (2000) has an electric power rate J of about 45%. In addition, Weng's electric power rectification increased the removal rate of the laterally sticky soil from the voltage drop method to 44.6% from 44.5%. When the heart reaches 3 ―, TCE Sa Zhigao et al. (1996) can prepare lead and cadmium 224 mg with viscous 瓖+, 婳 at 纟 以^ with 71, /, shell loam, enamel sand and clay. g, can be dyed soil, in the addition of 〇 · 1 M HC1 electrodynamic method 0 ^ 997 i ° ^ # _ At year into the eucalyptus to pay through the soil and simulate the soiled cadmium, mouth ▲ sad And the electric power method was used to carry out the rectification of 5 - 2 2 days. The results showed that the heavy metal of the actual soil and the soil iron and manganese oxide showed a strong combination. After 2丨天正=cadmium, the cadmium has been removed. However, lead still has no significant removal effect. f production support 人 ^ people (1 999) with three soils to prepare cadmium containing about 5 〇〇叩 / "soil ^ soil ' small reaction tank 5 - 3 〇 days and large reaction tank 18 〇 days electric power rectification, compare The influence of environmental factors such as organic matter, additive liquid and soil texture on the movement of pollutants in the tank. In addition, Huang Jiayu and Sazhigao (2 〇〇〇) carried out two-dimensional electrodynamic rectification and three-day model test of contaminated soil. It is predicted that the longer-term test will obtain an average removal rate of 75 % in the near-anode region; the other six soils containing penta-chlorophenol will be regenerated by electrokinetic method, and it is found that the addition of quartz sand can accelerate the electroosmotic flow' and pH. The higher the value, the better the degradation (Cai Zaitang et al., 2〇〇〇). Yiqing special person (200a, 2 0 0 0 b) added a single or composite surfactant to rectify the artificial synthesis of 1, 〇〇mg/kg of ethylbenzene and xylene in soil; another addition of £0,4, citric acid, 303, tap water for the artificial synthesis of 25〇11^/1^ containing Cr(III) clay for electrodynamic rectification. Jing et al. (2〇〇1) carried out a 2 hr sludge dehydration study with a 2-5 V/cm electrokinetic method. The sludge moisture content can be 7 3 %

Page 13 V. Inventions (7) Ethylene pollution, Wengzhi zero-valent iron fell to 47.5%. Yuan Jing et al. (2〇〇2) explored the location of the preferred zero-valent iron powder reaction wall in electrodynamic remediation of four & mucoid soils. Huang et al. (2003) used SDS anionic surfactant to enhance the treatment of tetrachloroethylene contamination in clay soil by electricity and green wall method. Gu Jinquan et al. (200〇) determined the chemical structure change of arsenic in the treatment of copper ore slag by on-line EXAFS; Zhang Rihang and Liao Yingzhi (2〇〇2 ” force the anode and cathode area to circulate liquid and add acetic acid, phosphoric acid, carbonic acid Salt,::Electric power: Department, 11 values, and further explore the second T of the improved electric power system: Zhang Rixing et al. (20 03) conduct zero-valent iron and electrodynamic method: anti-ethylene pollution Soil research. 丨J set month forty-eight quintessence L Applicant-Zhang Kunsen began to study electric power, ▲, Meng π soil damage research in 1 997, and research and development "(first generation) improvement = heavy Should be grooved (Zhang Kunsen '1 998, Annex I reference), with sand, = force reverse = soil removal ^ into a lower content (about < 150 mg / kg) Cd, pb contaminated soil, quality 'into 29 After the test, the Cd can reach 92_99% removal rate within 2 days ^ two soil standards, Pb is slightly lower (2" 4%). Zhang Kunsen et al. (1999) take Taoyuan County Guanyin Township, Zhuzhu Township (5), pb ::: :Electric power rectification, Cd removal rate can be as high as 96%, after the rectification is near background = private, but Pb can not be removed. After that, "electrolytic acid, N s, Fe(N〇3)3, urine" as an additive, although the removal rate of Guanyin soil increased to 61%', however, the residual content is still "fourth grade" (higher than the background 栌ί observation) Zhang Kunsen et al. (2 〇〇〇) used the ultrasonic wave to carry out the soil 'sand, kalingi, Guanyin soil in the 20 _ ultrasonic shock action 1 removal rate can reach 16%, 49%, 74%, respectively, the effect However, montmorillonite 1249441 V. Description of invention (8) The content of Luzhu died after ultrasonic shock, which is supposed to be due to the fact that the two soils have 2:1 type Si, A1 layer clay minerals, and supersonic oscillations. The result is the desorption of heavy metals between the layers. After the ultrasonic pretreatment, the electrodynamic rectification of Guanyin soil and Luzhu soil is carried out, and the Cd content can be reduced to 〇· 5-〇· 7 mg/kg, which is very close to the background standard. And the pb removal rate of Guanyin soil can be greatly increased to 85-99%, and the residual Pb i is close to the monthly soil standard; however, the ABS soil due to the ultrasonic pretreatment will increase the Pb content, and then the subsequent electrodynamic rectification will not be possible. Below the initial pb ^ amount. Zhang Kunsen et al. (200 1) seeks no guidance The method of extracting heavy metals from soil by the method of “HC1, ci trie acid, electrolytic acid, EDTA, SDS, and strontium” when the heavy metal is dissolved excessively, and then the concentration is low (because the cost is low) and the effect is still Jiazhi 0·01 M EDTA is used as an auxiliary liquid for electrodynamic remediation, and no ultrasonic pretreatment is applied. As a result, the Cd removal rate of Guanyin and Luzhu soil after remediation is >97%, and the content of 歹曼(四) has been reduced to the background soil standard. The results are very good; as for the removal rate of Guanyin soil and Luzhu soil (9), it can reach 68% and 33%. The above-mentioned electric power rectification study of ι 998-200 was the initial study of a patent applicant, Kun Kunsen. During this period, the basic electric power remediation technology was established and the first generation of improved electrodynamic reaction tank was developed. 4. Comprehensive evaluation of research and technology of heavy metal pollution in domestic and international electric power remediation: I. Investigate the above-mentioned domestic and international electric power remediation of heavy metal contaminated soil research and ^ surgery' = analysis as follows: (1) most electric rectification biased In the academic name 2 research 7:, and the technical breakthrough of the future from the perspective of practical application and (1) most of the electrodynamic reaction tank is a closed reaction tank, and the jade > 〇 〇 壌 all and completely placed in the cathode Between the anode and the anode, so the reaction tank

1249441 V. INSTRUCTIONS (9) "The middle section j and the "near cathode section" are prone to form heavy metal deposits and cannot be removed. (3) In order to prevent heavy metals from sinking in the reaction tank, or / and promote the desorption/dissolution of heavy metals in the soil, or / and formation of soluble metal complexes, hydrochloric acid, acetic acid, citric acid, phosphoric acid, EDTA are often added to many electrodynamic treatments. Such as acid or chelating agent, this will increase the cost of remediation, or / and cause secondary pollution (including the soil due to the addition of acid or chelating agent to produce another pollution, the electrode area produces c and other parent gases). (4) Part of the reaction tank is equipped with high head equipment in the anode area, and the high water gradient is used to cause the flow of soil pore water to promote the weight after desorption, which belongs to removal. Only the system must be a closed reaction tank. Therefore, the soil remediation is less and less, and the operation and monitoring are inconvenient. In addition, in order to promote the desorption and removal of heavy metals in the soil, the high head equipment often also adds acid or chelating agent. . (5) Most researchers have used soils with heavy metal content of more than hundreds or thousands (four)/kg as remediation targets. However, such high content is often much higher than that of actual contaminated soils (eg σ / Heavy metal pollution of agricultural land). Exploring the cause, it is a high concentration of pollution, and it is more mobile in the electric field. Therefore, under the same "remediation removal rate", the remediation of low-level pollutants with high-yield remediation is easy to achieve, but in terms of the effect of treatment The remediation removal rate is not important, and whether the residual pollutant content in heavy soil is lower than the regulatory standards. In addition, due to the many reactions in the electrodynamic rectification system and the mutual influence, the following measures should be taken for the electrodynamic rectification method of the future practicality. ▲ (1) Mastering the most favorable contaminant removal Reaction / effect. (2) Minimize other reactions/actions. (3) Although the development of remediation technology is mainly, it still has to take into account the cost of remediation, remediation time, and ease of operation. 1244841 1-5. Inventions (10) [Inventive power generation power is the system, internal division The buffer slot and the buffer unit are connected to the board. In addition, the method is to re-execute the electricity, first clearing the phenomenon; in the tank, the anode is filled with heavy metal, and the technical hand is added. The goal is to provide a solution to the shortcomings of the conventional technology. It is a system and method for contaminated soil.

In order to achieve the foregoing object, the present invention provides an electrodynamic anti-reaction tank containing-opening outer tank body, the outer tank body having a soil sub-tank separated and a buffer sub-tank, the soil sub-tank And a deposition zone is formed, and the two electrode regions are respectively located outside the soil sub-slot, and an electrode plate is respectively disposed therein; and an electric power supply is connected to the electrode plate of the two electrode region for providing DC power to the second electrode S, the present invention further provides an electrodynamic rectification of heavy gold lip contaminated soil with the following steps: First, an electrodynamic reaction system is prepared; solution: adding an appropriate amount of water to the reaction tank of the electrodynamic reaction system to electrify the water body until The anode and cathode regions are acid and ϋ, and then the remediation process is carried out: the soil to be rectified is placed in the water: 1 The voltage is adjusted for electrodynamic rectification, and the electrokinetic reaction system is used to continuously flow the acid front of the Η+ ion. Soil and ion exchange and dissolution reaction with soil; repeated monitoring procedures: including the amount of water in the appropriate reaction tank, controlling the remediation current and taking the lifting and remediation into sections; OK determination program: judged by a change of the current regulation ^ remediation.疋 】

Page 17 1249441 V. Description of Invention (11)::: Ming:: The present invention - a preferred embodiment, and with the diagram of the advancement - step by step of the electric power rectification of heavy metal contaminated soil: single two: two Constructed into electric power anti-reaction-reaction tank] 2 and - electric power: sub-tank: rr rushing 2 sub-: two:: think 22, two bottom one, one soil, the two-slot body 22, opening upwards open The length-to-height ratio of the tank body is ^, "height·width = 〇·5 - 3··1 〇-踹: ί, 24 series detachably placed opposite the bottom side of the outer tank body 2 The trough=width=the height of the soil trough and the buffer sub-slot are mostly small: the body; the bases 23 and 24 may be single-block or by, and the soil sub-tank 26 and the buffer sub-tank 28' are open upwards. Open trough: Distance: # Ϊ : The top sides of each base 23, 24 are separated from the inner wall of the outer trough body 22: 30 (; form a water body area 27, form between the bottom part - precipitate this, gradually rise, ...: Gold = material: soil sub-tank 26, buffer sub-tank 28 and outer tank body = 7 ΓΓ 36, each of the electrode regions 34, 36 is provided with -" two electrode plates 38, 40 graphite electrode plates, the area of which is The outer tank body 22 can utilize a cross section "Area" (ie, "outer groove body 22 cross-section surface ^mrn page 18 1244941 5. Invention description (12) This electrode plate 38 is integrated" deducts "base 23, 24 longitudinal section area" anode plate, the electrode The plate 40 is a cathode plate. Further, one side of the soil sub-tank 26 and the buffer sub-tank 28 electrode plates 38 and 40 is a perforated plate f h8; and the opposite side and the inner side adjacent to the punch groove 28 are respectively provided. Non-woven fabric, and the buffer sub-tank 26 and the quartz sand or glass beads which are slowly adsorbing heavy metal ions (the portion in the figure can be filled with the side of the sinking chamber 30 can be set - anion exchange =) / or /, The outer trough body 22 corresponds to the sacred area of the sacred area. Further, 2 5 and sighs the right dry sluice hole, the power supply unit 14 4, and connects the lei ## q 8 source 庳 5|, The IV 埕 士 + = electrode plates 38, 40, is a DC power supply benefit, to provide DC power to the two electrode plates 38, 40. According to this, as shown in Figure 3, the electric power method of the present invention is matched with the The steps of the electrodynamic reaction system 10 are as follows: the first step of the invention is that the heavy metal contaminates the stone and the plant residue in the soil first. Roots, sundries, etc. are removed, and the remaining soil is smashed. After mixing, it is ready to be smashed. (Dimensions <0.5cra 士八j^ The first step is to prepare the electrodynamic reaction system 10. The tenth step is to carry out the electrolysis process: adding 0 1 water or the treated water in the reaction tank 12 to about six or seventy percent full. The electric power is turned on for the early 14 and the output voltage is 5〇. _1〇〇ν. Then monitor the Η value of the cathode region of the anode region of the reaction tank, and the PII values of the anode and cathode regions respectively show about 4, > 10, and the power can be temporarily turned off, and the soil to be reconditioned is placed therein. The soil sub-tank 26, f is added to the water level in the reaction tank 12 to slightly cover the soil to be rectified. The fourth step of the present invention is to carry out the remediation process. · Start the energization to complete the whole 1249441 V., less / σ 'remediation and adopt fixed voltage output, the range is 2 〇 _ 丨〇 〇 V. During the remediation, the electrode zone j (anode zone) produces a high concentration of Η+ ions, and the acidic front continues to flow through the soil raft (3) 26 ′ and ion exchange or/and dissolution reaction with soil heavy metal contaminants. The main chemical formula of this step is as follows: The electrolysis of the water in the anode region of the sheet I produces the acidic front of hydrogen ions (Η+), which is close to the diffuse layer of the electric double layer on the surface of the soil by mass transfer (1 Ξ S - L - M + H + ξ S - L - Μ ... H + (2) eS-ML + Η + — eS — M — L", H+ (3) Three SM + H+ Three S-Μ···Η+ 2·H hydrogen The ion (H+) enters the inner stern layer of the electric double layer on the surface of the soil, and exchanges with the heavy metal of the soil to desorb the heavy metal. (1) Three SLM + H+ — eS_L-Η + Mn+ (2) Three SML (or eS-L -Μ) +H+ eS-H + ML (or L - M) (3) One Μ + H+ Three S — H + Mn+ 3· Partially deposited heavy metal precipitate on the surface of the soil, due to Dissolve by contacting the acidic front (dissolution) S · MA (S) + H + - three S + Mn + + HA (m_1) _ (or Α π b)

1249441 V. _, invention description (14) - The pre-existing chemical symbol and its related description are as follows: 1. Chemical formula: (1) "Three S" is the soil surface (s〇il surface). (2) "M" is a metal contaminant or / and hydrated metal contaminant (ffletai 〇r/and jydrated metal). (3) "L" is a ligand (Hgand "A' organic matter (can), simplification, L is not priced. (4) /" is an anion (ani〇n). (5) "·" is deposition (deposition ; ° 2 · ( 1 ) soil surface surface disk pollution is common, most of them are single bond mismatch or ^ may be double bond error (2) eS-L and three S-Μ Lm mismatch It is not a double bond mismatch reaction. It is not listed. (3) H+, because of the exchange reaction with -, three 3-L-Μ heavy metals, is the first 1 protonic acid or / And the two protonic acids are not chemically balanced. ―In the morning, the beginning, the sputum, unless necessary, the fifth step of the present invention, & affairs include: (1) daily timing: D, test procedure: During the remediation, it is necessary to pay special attention to the current of the first day, to capture the current of the reaction tank, and record the c

A, should be moderately reduced the fixed electricity problem "Caizhou · does not welcome 0. 5 A, if the current is higher than the water tank during the treatment period U's water eight ' / current is lower than 〇. 5 A. (2), charging reaction The amount of water in the tank, the water Dan 2 is lost due to natural bursting, so it should be timely (3) to promote the soil to be rectified, and slightly cover the soil to be rectified. The following practices are adopted: a J f metal can be faster Remove the soil, you can drive the voltage of 14 about 50-1〇〇v voltage · Daily increase power supply. Add ozone to the single month tank 26: In:: about 5-15 melons in between: 4) In the soil ^ into the carcass , every time you inject ozone 丨 ~ 2

Page 21 1249441 V. Description of invention (15) The ozone flow rate is about 3-1〇g ·〇次, each... -------- ^ / kg · soi 1 /hr, each injection time is about 5 -1 0 mi η. (4) During the remediation period, the amount of sludge in the sedimentation zone can be seen as the amount of sludge, and the sludge will be removed by opening the mud hole. (5) In order to reduce the polarization of the electrode, it is possible to examine the deposit of the deposit on the electrode plate 38, 40, and replace the new plate (the deposit on the old electrode plate can be reused after scraping, and the deposition is scraped off) The heavy metal concentration of the substance was detected by TCLP 'reprocessing/disposal according to the normal treatment procedure of sludge. The sixth step of the present invention is to carry out a judging process: if the monitoring of the electric production of each enthalpy has been gradual, and there is no significant decrease in about 2-3 days, that is, the removal of the owing material has stopped, so Turn off the power to stop the remediation. Waste: After the effluent hole of the outer tank body 22, the sludge and the reaction tank U are all concentrated in the sputum, and the waste water of the slag is filtered, and the solid matter is detected by TCLP. The normal treatment procedure is followed by treatment/disposal. The wastewater of the second π mud is tested for its heavy metal concentration: for subsequent treatment. And the removal of the completion of the rectification: the standard inspection method of the Department of Management (Wang Shui Dismantled), after the environmental protection is lower than the "soil smuggling gamma, then its sputum" test the total amount of heavy metals in the sample, re-cultivation to the background soil soil :", then the batch has been rectified and the soil has been waited. ...the soil fertility, set back to the original site or for general soil use. In short, the electric power of the invention is divided into two parts: hardware and software: genus, technology that can be soiled and damaged. Area A · Hardware aspect 1249441 BRIEF DESCRIPTION OF THE DRAWINGS (16) Figure 2 The electrodynamic rectification hardware aspect of the present invention includes (see Figure 1) The second generation electrodynamic reaction tank: the outer tank body is an open trough body, and the aspect ratio is "long: width = 2-5 : 1", "High: Width = 〇 · 5 - 3 · 9 脰 only 2. Different widths of the hand groove body: the sub-tank body is also open type, 'the sides are the ϋ 孔 孔 plate' can be placed in the reaction In the tank, it is used as "soil sub-tank" and "buffer: electrode area." 3. Combined solid base: The base is a solid unit designed to match the height of the outer tank. The unit can be combined. In the Department of Hearts, the main function is to create a "precipitation zone" below the two sub-grooves of the "soil box" and "^ early groove" of different widths, and the "precipitation zone" is required to be fixed. 4. The soil sub-tank is close to the anode: the anode is electrolyzed by water, followed by strontium + ion production. The acidic front edge flows to the cathode, this === : π spring passes through the soil sub-tank and the soil heavy metal pollutants are generated from the knife exchange or / and each reaction 'to achieve the purpose of heavy metal pollutants removed from the soil. Mainly by the combined solid base Create a "precipitation zone" ' 言 ^ ΐ Remove the pollutants from the soil sub-tank because the pH of the water body gradually rises = two right ^ into heavy metal oxides can be successfully settled in this area. This area can be based on the whole ' Further one or more mud holes are provided at the bottom or/and sides of the reaction tank, so that heavy metal precipitated sludge can be discharged from the bottom of the sedimentation tank. - 6· $ punch tank area: buffer tank area is mainly buffered" The alkaline front edge "0" moves away from the direction of the anode to the anode, so as to prevent the alkaline front edge from colliding with the heavy metal removed from the soil sub-tank to precipitate. To achieve this, the sub-tank: (1)

Page 23 1249441 ^--------, quartz sand or glass beads that do not adsorb heavy metal ions to increase the curvature and difficulty of movement of the ions in the pores. (2) or / and add an anion exchange membrane adjacent to the "Shen Ying District" to make H+ ions and heavy metal ions difficult to pass through, while 0H ions pass through the membrane from the "buffer sub-tank" into the "precipitation zone", or with H+ The ions form water or form precipitates with heavy metal ions to settle in this region. 7 • Sub-tank lining: The lining of the “soil sub-tank” and “buffer sub-tank” is non-woven to prevent the loss of quartz sand or glass beads in the soil or buffer tank outside the sub-tank. B · Soft body Aspects of the electrodynamic rectification operation and the like of the present invention include: 1. Before the rectification, the electric body is first electrolyzed to electrolyze the water first: the soil is first energized before being placed in the reaction tank to allow the water body to be electrolyzed first, so that the anode and the cathode can be made. The area produces H+ and 0H-ions from Sui and Tang dynasties to facilitate the remediation ability of the soil after the soil is placed. 2. Add a small amount of water as needed. This second-generation reaction tank system does not require continuous water addition (the first generation requires ), avoiding excessive waste water and saving subsequent water treatment costs. In the second generation of the reaction tank, the soil and the water do not heat up and evaporate water at a fixed low voltage. Therefore, only a small amount of water due to natural evaporation needs to be added daily. ........ 3·Using DC fixed voltage: the fixed voltage of the DC power supply wheel is out, the range is 20- 00 V, and the rectification current is based on the principle of not exceeding 〇· 5 A on the first day. Above 〇. 5 A, the fixed voltage should be lowered. ' ” 4· Potential drop of each sub-tank: (1) “Soil sub-slot” potential drop should be maintained

Page 24 1249441

At 0·2-8· 0 V/Cin, to remove heavy metals. (1 drop does not need to be controlled. ,, his sub-slot area is in 〇 · 02-0· 5 · Reaction tank current density · · Reaction tank current density should be maintained 5 m A / c m2 〇 ' Unearthed i promoted ίί: Shift: The method of promoting the heavy metal can quickly remove the soil. The following intermittent methods: (n boost the voltage rise power supply ^ voltage about 50_1 () 0 v, duration of about 5_15 _, so can promote soil The removal of heavy metals. (Preparation + 毺 毺 A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A 犬 犬 犬 犬 犬 犬 犬 犬 犬 犬 犬 犬 犬Stained two === 3-10 g ·〇3/ kg · SQil /hr. ,, skunk ice plus $,,, spoon, if J: 2::::5, rectification, need to monitor current The change, the right thorn thorn motor tends to be gentle for about 2 to 3 days, that is, two. In summary, the 'mouth system and method' provided by the present invention is not only advanced electric JU metal contaminated soil - Substituting electric power remediation method, remediation technology' and super-verification of soft and hard bodies, heavy metal content after remediation, heavy metal contaminated soil New Concept remediation technologies. The present invention is expected ball solid two-level view, it is a very environmentally friendly create an application. Male elements consistent pay θ invention patent, mention law Yuan

1249441 BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic view of an electrodynamic reaction system in accordance with a preferred embodiment of the present invention. Figure 2 is a schematic view of a reaction tank in the electrodynamic reaction system of the present invention. Figure 3 is a flow chart of a method for rectifying heavy metal contaminated soil by electrodynamics according to a preferred embodiment of the present invention. Description of the figure: Power supply unit 1 4 Discharge hole 2 5 Buffer subtank 28 Electrode plate 38, 40 Electrodynamic reaction system 10 Reaction tank 1 2 Outer tank body 2 2 Soil sub-tank 26 Shen Dian area 3 0 Base 23, 24 water body area 2 7 electrode area 3 4, 3 6

Page

Claims (1)

1249441 Sixth, the scope of application for patents 1 · An electrodynamic reaction system, comprising a reaction tank, comprising an open outer tank body, the outer tank body is separated by a soil sub-tank and a buffer sub-tank, the soil A precipitating zone is formed between the sub-tank buffer sub-grooves, and the two electrode regions are respectively located outside the soil sub-tank and the buffer sub-tank, and an electrode plate is respectively disposed therein; a power supply unit connecting the electrodes of the two electrode regions A board for supplying direct current to the two electrode plates. ', 2 · According to the electric power reaction system of claim 1, wherein the open outer tank has a length to width ratio of "length: width = 2 - 5 : 1", "height : width = 0.5" —3 :1”. 3. The electrodynamic reaction system according to claim 1, wherein the soil sub-tank and the buffer sub-tank are open troughs inside the outer tank body. 4. The electrodynamic reaction system according to item 3 of the patent application scope, wherein the base unit further comprises two bases, each of which is respectively placed on the bottom side of the soil sub-tank and the buffer sub-tank for being used after being raised The soil sub-tank forms a sedimentation zone with the buffer sub-tank. & 〇P 5 ·According to the electrodynamic reaction system described in item 4 of the patent application scope, each of the bases of the complex is combined with the inner width of the outer tank body and the combined solid solid of the soil sub-groove, buffer 粬, i degree Seat. g ^ , its , its side 6. According to the electric power reaction system described in item 5 of the patent application scope, the base system is detachably placed on the bottom side of the soil sub-tank and the buffer sub-tank> 7: According to the fifth item of the May In the electrodynamic reaction system, the opposite side of the soil sub-slot and the buffer sub-tank and the adjacent electrode are respectively arranged as a porous plate. Page 27 1249441 VI. Application Patent Range ^ ~~β^ --^ -- 8· According to the electrodynamic reaction system described in claim 1 or 3, wherein the inner side of the soil trough and the buffer sub-tank are There are non-woven fabrics. 9) The electrodynamic reaction system according to claim 1 or 3, wherein the inside of the buffer tank is filled with quartz sand or glass beads which do not adsorb heavy metal ions. 10. The electrodynamic reaction system according to claim 9, wherein the buffer tank is provided with an anion exchange membrane adjacent to one side of the precipitation zone. 11. The electrodynamic reaction system according to claim 1, wherein the outer tank body is provided with a plurality of mud holes corresponding to the position of the sedimentation zone. 1 2 . The electrodynamic reaction system according to claim 1, wherein the electrode plates of the electrode regions are graphite electrode plates. 1 3· According to the electrodynamic reaction system described in claim 12, wherein the area of each of the electrode plates is “the area of the cross-section available for the outer tank body” (ie, the cross-sectional area of the outer tank body) Deduct the "base section area"). The electric power reaction system according to claim 1, wherein the power supply unit is a DC power supply. 1 5· — A method for rectifying heavy metal contaminated soil by electric power, comprising at least the following steps: a) preparing an electrodynamic reaction system; b) electrolysis procedure: adding an appropriate amount of water to the reaction tank of the electrodynamic reaction system The water body is electrolyzed until the anode and cathode regions exhibit acid and alkali distinct phenomena; c) the remediation procedure: the soil to be reconditioned is placed in the reaction tank of the water, and the voltage is adjusted for electrodynamic rectification, and the anode of the electrodynamic reaction system is utilized. Production 1249441 --------- - VI. Application for patent scope ^ '~"" ' ^~-- The acid front of the high concentration H+ ion continuously flows through the soil and ion exchange and dissolution with heavy metals in the soil Reaction; d) Monitoring procedure: including timely replenishment of the water volume of the reaction tank, control of the remediation current and technical means to improve the remediation effect; and Shangzheng e) Judgment procedure: judging whether the rectification has been completed by the change of the rectification current 〇16. The method of claim 15, wherein in the step b), about six or seventy percent of the water is added to the reaction tank. The method of claim 6, wherein the added water is tap water or distilled water. 1 8. According to the method of claim 5, wherein in step b), the adjustment voltage is 50-ιοον. 19, according to the method described in claim 15 of the patent application, wherein in the step b), the anode and cathode regions exhibit acid and alkali separation, meaning that the pH values of the anode region and the cathode region respectively represent about <4 , > 1〇. "" 20. According to the method described in claim 15 of the patent application, in the step c), when the soil to be treated is placed in the reaction tank, the water is slightly covered to be treated. & 21. According to the method of claim 15 of the scope of the patent application, wherein c) step t, a constant voltage of 20 - 1 00 V is used. ^ P 2 2 · According to the method described in item 5 of the patent application, in the step d), the standard of the amount of water supplemented is such that the water is slightly covered to be cured. 2 3 · According to the method of claim 15 of the scope of patent application, in step d), the current value of the remediation is less than 〇. 5 A. Μ Page 29 1249441 VI. Scope of Application for Patent 2 4 · According to the method described in item 15 of the scope of application for patent application, in step d), the technical means to improve the effectiveness of remediation is to increase the voltage: daily increase of the power supply The voltage is about 5 〇 - 1 〇〇v and the duration is about 5 -1 5 mi η. 2 5 · According to the method described in item 15 of the patent application scope, in the step d), the technical means of improving the effectiveness of remediation is to add ozone to the soil sub-tank: the method of injecting gas, injecting ozone into each 2 times, each ozone flow rate is about 3-10 g · 〇 3 / kg · soi ! /hr, each injection time is about 5-10 mi η 〇 2 6 · According to the method described in item 5 of the scope of patent application, in the step d), the technical means of improving the effectiveness of remediation is based on the amount of sludge in the Shendian District of the electrodynamic reaction system. The holes remove the deposited sludge. ^7. According to the method described in claim 15 of the patent application, wherein d) step ^ adopts a technical means for improving the effectiveness of remediation, and examines the amount of deposit on the electrode plate in the electrodynamic reaction system to replace the new electrode plate. 28· ^ According to the method described in claim 15 of the scope of application, wherein e) step means that the daily monitoring current change has been flattened and there is no significant decrease or low for about 2 to 3 days. -