JP2004122049A - Purification method of soil and ground water - Google Patents
Purification method of soil and ground water Download PDFInfo
- Publication number
- JP2004122049A JP2004122049A JP2002292387A JP2002292387A JP2004122049A JP 2004122049 A JP2004122049 A JP 2004122049A JP 2002292387 A JP2002292387 A JP 2002292387A JP 2002292387 A JP2002292387 A JP 2002292387A JP 2004122049 A JP2004122049 A JP 2004122049A
- Authority
- JP
- Japan
- Prior art keywords
- groundwater
- soil
- water
- injection well
- chemical
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Landscapes
- Investigation Of Foundation Soil And Reinforcement Of Foundation Soil By Compacting Or Drainage (AREA)
- Processing Of Solid Wastes (AREA)
- Treatment Of Water By Oxidation Or Reduction (AREA)
Abstract
Description
【０００１】
【発明の属する技術分野】
本発明は、化学物質により汚染された土壌および地下水を原位置で物理化学的に浄化する方法に関する。本発明の浄化方法は、例えば有機塩素化合物に汚染された土壌および地下水の浄化に好適に使用される。
【０００２】
【従来の技術】
近年、土壌および地下水の様々な化学物質による汚染が顕在化し、その対策が急がれている。特に、洗浄剤として各種工場やクリーニング店で広く使用されているトリクロロエチレン、テトラクロロエチレン等の有機塩素化合物は、発癌性物質である疑いがあるため、これら有機塩素化合物による汚染には早急に対策を講じる必要がある。
【０００３】
従来、有機塩素化合物で汚染された土壌や地下水の処理方法としては、汚染土壌を掘削して分解剤を混合する分解処理法、汚染地下水を揚水して曝気処理や活性炭吸着処理を行うポンプ・アンド・トリート法などが主に用いられてきた。
【０００４】
しかし、土壌を掘削して分解剤を混合する分解処理法では、掘削に大規模な工事が必要であり、要する費用は多大なものとなる。しかも掘削による方法では、汚染土壌の上に建築物等がある場合、建築物の撤去等が必要となるため、浄化が困難なことも多い。また、地下水を揚水した後に処理を施すポンプ・アンド・トリート法では、浄化完了までに数年以上の年月を要する場合も多く、浄化期間の短縮が強く望まれている。
【０００５】
これに対し、上記問題点を解決するために、掘削を行うことなく、土壌および地下水に原位置で水または薬剤を注入することにより、土壌および地下水を浄化する方法が提案されている（例えば、特許文献１、２参照）。これらの浄化法において、通常、水は汚染化学物質の洗浄除去に使用され、薬剤は汚染化学物質の分解あるいは固定化（不溶化）に使用される。汚染化学物質の分解に使用される薬剤としては、過マンガン酸塩、過硫酸塩等の酸化剤が多く用いられる。また、水または薬剤は、通常、土壌中を地下水が流動する地下層である帯水層に注入される。
【０００６】
【特許文献１】
特開２０００−４２５３７号公報
【特許文献２】
特開２０００−５１８３４号公報
【０００７】
【発明が解決しようとする課題】
しかしながら、土壌および地下水に原位置で薬剤を注入する方法では、薬剤はそれ自身が生物種に対して毒性を持つことが多いため、注入後の薬剤を帯水層中に放置することは好ましくない。また、土壌および地下水に原位置で水を注入する方法では、注入された水は汚染化学物質を含むため、この水を処理対象域外に漏洩させることは好ましくない。
【０００８】
本発明は、前述した事情に鑑みてなされたもので、土壌および地下水に原位置で水または薬剤を注入することにより、土壌および地下水を効率的に浄化することができるとともに、注入した水または薬剤を処理対象域外に漏洩させずに地下から回収することができる土壌および地下水の浄化方法を提供することを目的とする。
【０００９】
【課題を解決するための手段】
本発明者らは、前述した目的を達成することができる最適なシステム構成の検討を水理学的な観点から行った。その結果、注入井戸の周囲にその注入井戸を囲うように少なくとも３本の揚水井戸を配置し、地下水および土壌への注入井戸からの水または薬剤の注入量と、揚水井戸からの地下水の揚水量とを適切にコントロールすることにより、処理対象域内の地下水および土壌の浄化を効率的に行うことができ、しかも注入した水または薬剤を確実に回収できることを見出した。
【００１０】
本発明は、上述した知見に基づいてなされたもので、化学物質に汚染された土壌および地下水に原位置で水または薬剤を注入して土壌および地下水を浄化するに当たり、１本の注入井戸に対しその注入井戸を囲うように３本以上の揚水井戸を配置し、前記注入井戸から土壌および地下水に水または薬剤を注入するとともに、前記各揚水井戸から地下水を揚水することを特徴とする土壌および地下水の浄化方法を提供する。
【００１１】
本発明では、注入井戸から注入された水または薬剤が、汚染された土壌および地下水と接触することにより、汚染化学物質の洗浄除去、分解、固定化等がなされ、土壌および地下水が浄化される。この場合、本発明では、注入井戸から水または薬剤を注入しつつ、注入井戸を囲う３本以上の揚水井戸から地下水を揚水するので、水または薬剤は注入井戸からその周囲の各揚水井戸に向けて流れる地下水とともに注入井戸の周囲に広がり、処理対象域内の地下水および土壌の浄化が効率的に行われる。また、注入井戸から注入された水または薬剤を各揚水井戸から地下水とともに回収することができ、したがって注入した水または薬剤が処理対象域外に漏洩することを防止することができる。
【００１２】
【発明の実施の形態】
以下、本発明についてより詳しく説明する。本発明において浄化対象とする物質は、化学物質に汚染された土壌および地下水であり、汚染化学物質としては、主にｃｉｓ−１，２−ジクロロエチレン、トリクロロエチレン、テトラクロロエチレン等の有機ハロゲン化合物を対象としているが、ＶＯＣ（揮発性の有機化合物）以外の油、ダイオキシン類、芳香族化合物等による汚染はもとより、原位置で水または薬剤を注入して汚染化学物質の分解、洗浄、固定化等を行う種々の土壌および地下水の浄化処理に対して本発明は適用が可能である。
【００１３】
本発明においては、１本の注入井戸に対しその注入井戸を囲うように３本以上の揚水井戸を配置する。すなわち、１本の注入井戸のまわりを取り巻くように３本以上の揚水井戸を配置すればよく、注入井戸および揚水井戸の配置態様にその他の限定はない。そして、注入井戸から土壌および地下水に水または薬剤を注入するとともに、各揚水井戸から地下水を揚水する。なお、水または薬剤の注入および地下水の揚水を行う地下層は、通常、前述した土壌中を地下水が流動する帯水層である。
【００１４】
本発明における注入井戸および揚水井戸の配置例を図１に示す。図１において、注入井戸は●、揚水井戸は○で示してある。図１（ａ）は１本の注入井戸を３本の揚水井戸で囲った例、（ｂ）は１本の注入井戸を４本の揚水井戸で囲った例、（ｃ）は１本の注入井戸を６本の揚水井戸で囲った例、（ｄ）は６本の注入井戸を配置するとともに、各注入井戸をそれぞれ４本の揚水井戸で囲うように計１２本の揚水井戸を配置した例である。（ｄ）の例では、一部の揚水井戸は２本以上の注入井戸を囲うために兼用されている。これらの中で特に好ましいのは、薬剤の影響範囲を広く取れる点、および井戸の掘削費用の点から、１本の注入井戸を４本の揚水井戸で囲う（ｂ）、（ｄ）の例である。
【００１５】
本発明の範疇に入らず、本発明の効果を得ることができない注入井戸および揚水井戸の配置例を図２に示す。図２において、注入井戸は●、揚水井戸は○で示してある。（ｅ）は１本の注入井戸と１本の揚水井戸とを対向配置した例、（ｆ）は３本の注入井戸と３本の揚水井戸とを対向配置した例、（ｇ）は１本の揚水井戸を４本の注入井戸で囲った例、（ｈ）は１本の注入井戸のみを配置した例である。（ｅ）、（ｆ）の例では注入した水または薬剤が注入井戸の周囲に広がらず、（ｇ）の例では注入した水または薬剤が処理対象域外に漏洩し、（ｈ）の例では注入した水または薬剤の広がりが遅い上、水または薬剤が処理対象域外に漏洩する。
【００１６】
本発明において、土壌および地下水に薬剤を注入する場合、薬剤として酸化剤を用い、汚染化学物質を酸化分解することが好ましい。酸化剤の種類に限定はなく、例えば過マンガン酸塩を用いることも考えられるが、過マンガン酸塩を用いた場合には、反応生成物として二酸化マンガンを生成して帯水層を閉塞する可能性があること、過マンガン酸塩は土壌中の有機物との反応性が高く薬剤消費量が増大すること、マンガンは水道法水質基準等で濃度規制されている物質であること、過マンガン酸塩は過硫酸塩に比べて水生生物に対する毒性が高いことなどから、本発明では酸化剤として過硫酸または過硫酸塩を用いることが特に適当である。過硫酸塩としては、例えば、過硫酸カリウム、過硫酸ナトリウム等を用いることができる。注入した酸化剤の地下水中における濃度は、汚染化学物質の種類や土壌の性状等によって異なるが、概ね反応領域末端（浄化範囲の末端）において１０ｍｇ／Ｌ以上、特に５０ｍｇ／Ｌ以上であることが望ましい。
【００１７】
注入井戸からの薬剤注入量、および注入井戸と揚水井戸との距離間隔は、その反応領域での薬剤の水理学的滞留時間が２時間以上、より望ましくは１２時間以上となるように調整すればよく、また注入量に対する揚水量の比率は、等量から数倍の間で薬剤の処理対象域外への漏洩がなく、かつ薬剤の拡散が効率的に起こる範囲で決定すればよい。上記注入量および揚水量は、例えば地下水の基本流動式（連続の式）等を用いたシミュレーション計算により決定することができる。この場合、上述したシミュレーション計算に用いるパラメータとしては、浄化対象帯水層の透水係数、地層構造、地下水流れ方向、速度等を用いる。
【００１８】
注入井戸から注入する薬剤の濃度（薬剤溶液中の薬剤濃度）は、汚染化学物質の濃度や種類により異なり、通常は現場における汚染水を用いたトリータビリティ試験の結果により決定されるが、概ね１０〜１０００００ｍｇ／Ｌの範囲とすることが好ましく、薬剤溶液の保管等を考えると１００〜５００００ｍｇ／Ｌの範囲とすることが望ましい。薬剤は溶液としてタンクに保管し注入することも可能であるが、浄化が長期に渡る場合には固体のまま保存し、薬剤自動溶解装置等を用いて溶液を作成し、連続的に注入を行うことも可能である。
【００１９】
揚水した地下水中に汚染化学物質が含まれている場合において、その地下水中に酸化剤が十分量残存しているときには、揚水後に適当な期間静置しておくだけでも分解が進行し、汚染化学物質は分解されるが、揚水した地下水に曝気処理、紫外線照射処理、オゾン添加処理等の１種以上の処理を行うことにより、揚水した地下水中に含まれている汚染化学物質を分解してもよい。このようにして処理した地下水は、河川放流、下水放流等を行うことができるが、この地下水の一部または全部に所定濃度となるように薬剤を添加して再注入を行う方法は、コスト的、またシステム的にも非常に有効である。すなわち、本発明では、揚水井戸から揚水した地下水の一部または全部に薬剤を添加した後、この薬剤を添加した地下水を再び注入井戸から土壌および地下水に注入することができ、これにより未反応薬剤の有効利用、揚水した地下水を再利用することによるコスト削減を図ることができる。
【００２０】
地下水中は還元雰囲気になっていることが多く、その地下水中には２価の鉄イオンが含まれている場合が多い。この２価の鉄イオンは、揚水により空気と接触したり、酸化剤により酸化されたりすると酸化鉄となり、沈殿を生じる。この場合、揚水した地下水を注入用水として再利用するためには、酸化鉄や微細な土壌等の縣濁物をフィルタ処理や凝集沈殿処理等により除去することが適当である。
【００２１】
【実施例】
以下に本発明を用いて行った実施例を示す。なお、この実施例は本発明の範囲を限定するものではない。
【００２２】
トリクロロエチレン（ＴＣＥ）に汚染された土壌および地下水を浄化する手段として本発明方法を用い、現場にて浄化試験を行った。浄化対象範囲は１０ｍ×１０ｍの正方形で、その中心部に配置した１本の注入井戸より酸化剤を注入し、４つの隅部に配置した計４本の揚水井戸より地下水の揚水を行うシステムとした。また、酸化剤の処理対象域外への流出の有無を確認するため、地下水流向の下流側において浄化対象範囲の外に観測井戸を設置した。
【００２３】
地下水流解析プログラム（Ｍｏｄ Ｆｌｏｗ）を用いてシミュレーションを行ったところ、パーティクルトラッキング（注入物質を粒子と仮定して回収率を算出する手法）の結果より、注入井戸からの注入流量１ｍ３／ｈｒに対して、各揚水井戸からの揚水流量１ｍ３／ｈｒ、計４ｍ３／ｈｒの流量バランスが最適と判断された。また、注入する酸化剤濃度は、現場の汚染地下水を用いたトリータビリティ試験の結果より１５００ｍｇ／Ｌとした。
【００２４】
その結果、浄化処理前の地下水中のＴＣＥ濃度は５．２ｍｇ／Ｌ、浄化処理開始後３ヶ月経過時の地下水中のＴＣＥ濃度は０．０３ｍｇ／Ｌであった。また、浄化期間内において観測井戸で酸化剤は検出されなかった。さらに、シミュレーション結果を参考図面に示す。参考図面によれば、処理対象域内のＴＣＥが分解されていること、酸化剤が処理対象域外に漏洩していないことがわかる。以上の結果より、本発明によれば、化学物質に汚染された土壌および地下水を、短期間で効率的にかつ安全に浄化することが可能であることが確認された。
【００２５】
【発明の効果】
以上のように、本発明によれば、土壌および地下水に原位置で水または薬剤を注入することにより、土壌および地下水を効率的に浄化することができるとともに、注入した水または薬剤を処理対象域外に漏洩させずに地下から回収することができる。したがって、本発明によれば、化学物質に汚染された土壌および地下水を、短期間で効率的にかつ安全に浄化することが可能である。
【図面の簡単な説明】
【図１】本発明における注入井戸および揚水井戸の配置例を示す図である。
【図２】本発明の範疇に入らない注入井戸および揚水井戸の配置例を示す図である。
【符号の説明】
● 注入井戸
○ 揚水井戸[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for in situ physicochemical purification of soil and groundwater contaminated by chemicals. The purification method of the present invention is suitably used, for example, for purification of soil and groundwater contaminated with an organic chlorine compound.
[0002]
[Prior art]
In recent years, contamination by various chemical substances in soil and groundwater has become evident, and measures have been urgently taken. In particular, organochlorine compounds such as trichloroethylene and tetrachloroethylene, which are widely used as cleaning agents in various factories and cleaning shops, are suspected to be carcinogenic substances, so it is necessary to take immediate measures against contamination by these organochlorine compounds. There is.
[0003]
Conventional methods for treating soil and groundwater contaminated with organochlorine compounds include a decomposition method in which contaminated soil is excavated and mixed with a decomposer, and a pump and pump that pumps up contaminated groundwater to perform aeration and activated carbon adsorption.・ Treatment method has been mainly used.
[0004]
However, the decomposition treatment method in which soil is excavated and mixed with a decomposing agent requires a large-scale construction for excavation, and the required cost is enormous. In addition, in the case of the excavation method, when there is a building or the like on the contaminated soil, it is necessary to remove the building or the like, so that purification is often difficult. In the pump-and-treat method, in which treatment is performed after pumping groundwater, it often takes several years or more to complete purification, and it is strongly desired to shorten the purification period.
[0005]
On the other hand, in order to solve the above problems, a method of purifying soil and groundwater by injecting water or a chemical into the soil and groundwater in situ without excavation has been proposed (for example, Patent Documents 1 and 2). In these purification methods, water is usually used for washing and removing contaminant chemicals, and chemicals are used for decomposing or immobilizing (insolubilizing) contaminant chemicals. Oxidizing agents such as permanganate and persulfate are often used as agents used for decomposing polluting chemicals. Water or chemicals are usually injected into an aquifer, which is an underground layer through which groundwater flows in soil.
[0006]
[Patent Document 1]
JP 2000-42537 A [Patent Document 2]
JP 2000-51834 A
[Problems to be solved by the invention]
However, in the method of injecting the drug in situ into soil and groundwater, it is not preferable to leave the injected drug in the aquifer because the drug itself is often toxic to species. . In addition, in the method of injecting water into soil and groundwater in situ, since the injected water contains pollutant chemicals, it is not preferable to leak this water out of the treatment target area.
[0008]
The present invention has been made in view of the circumstances described above, and by injecting water or a chemical into soil and groundwater in situ, it is possible to efficiently purify the soil and groundwater, and at the same time, to inject the injected water or chemical. It is an object of the present invention to provide a method for purifying soil and groundwater that can be recovered from the underground without leaking out of the treatment target area.
[0009]
[Means for Solving the Problems]
The present inventors have studied an optimal system configuration that can achieve the above-described object from a hydraulic viewpoint. As a result, at least three pumping wells are arranged around the injection well so as to surround the injection well, and the amount of water or chemical injected from the well into the groundwater and soil, and the amount of groundwater pumped from the pumping well. It has been found that by appropriately controlling the amount of water and chemicals, the groundwater and soil in the treatment target area can be efficiently purified, and the injected water or chemical can be reliably recovered.
[0010]
The present invention has been made on the basis of the above-described findings, and in purifying soil and groundwater by injecting water or chemicals in situ into soil and groundwater contaminated with chemical substances, one injection well is used. Soil and groundwater, wherein three or more pumping wells are arranged so as to surround the injection well, and water or a chemical is injected from the injection well into soil and groundwater, and groundwater is pumped from each of the pumping wells. To provide a purification method.
[0011]
In the present invention, the water or the chemical injected from the injection well comes into contact with the contaminated soil and the groundwater, thereby cleaning and removing, decomposing, fixing, and the like the contaminant chemicals, thereby purifying the soil and the groundwater. In this case, in the present invention, groundwater is pumped from three or more pumping wells surrounding the injection well while water or chemical is injected from the injection well, so that the water or chemical is directed from the injection well to each of the surrounding pumping wells. It spreads around the injection well together with the flowing groundwater, and the groundwater and soil within the treatment target area are efficiently purified. Further, the water or the chemical injected from the injection well can be collected together with the groundwater from each pumping well, so that the injected water or the chemical can be prevented from leaking out of the treatment target area.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in more detail. The substances to be purified in the present invention are soil and groundwater contaminated by chemical substances, and the polluting chemical substances are mainly organic halogen compounds such as cis-1,2-dichloroethylene, trichloroethylene, and tetrachloroethylene. However, in addition to contamination by oils, dioxins, aromatic compounds, etc. other than VOCs (volatile organic compounds), water or chemicals are injected in situ to decompose, wash, fix, etc. polluting chemicals The present invention is applicable to the purification of soil and groundwater.
[0013]
In the present invention, three or more pumping wells are arranged for one injection well so as to surround the injection well. That is, three or more pumping wells may be arranged so as to surround one injection well, and there is no other limitation on the arrangement of the injection well and the pumping well. Then, water or chemicals are injected from the injection well into the soil and groundwater, and groundwater is pumped from each pumping well. The underground layer for injecting water or chemicals and for pumping groundwater is usually an aquifer in which groundwater flows in the above-described soil.
[0014]
FIG. 1 shows an arrangement example of the injection well and the pumping well in the present invention. In FIG. 1, an injection well is indicated by ●, and a pumping well is indicated by ○. 1A shows an example in which one injection well is surrounded by three pumping wells, FIG. 1B shows an example in which one injection well is surrounded by four pumping wells, and FIG. An example in which a well is surrounded by six pumping wells, and (d) shows an example in which six injection wells are arranged and a total of 12 pumping wells are arranged so that each injection well is surrounded by four pumping wells. It is. In the example of (d), some pumping wells are also used to surround two or more injection wells. Among these, particularly preferred are the cases of (b) and (d), in which one injection well is surrounded by four pumping wells, in that the range of influence of the drug can be widened and the cost of drilling wells can be increased. is there.
[0015]
FIG. 2 shows an example of the arrangement of an injection well and a pumping well that does not fall into the category of the present invention and cannot obtain the effects of the present invention. In FIG. 2, the injection well is indicated by ●, and the pumping well is indicated by ○. (E) is an example in which one injection well and one pumping well are opposed to each other, (f) is an example in which three injection wells and three pumping wells are opposed to each other, and (g) is one. (H) is an example in which only one injection well is arranged. In the examples of (e) and (f), the injected water or chemical does not spread around the injection well, in the example of (g), the injected water or chemical leaks out of the treatment target area, and in the example of (h), the injected water or chemical does not spread. The spread of the water or chemicals is slow, and the water or chemicals leak out of the area to be treated.
[0016]
In the present invention, when a chemical is injected into soil and groundwater, it is preferable to use an oxidizing agent as the chemical and oxidatively decompose contaminant chemicals. There is no limitation on the type of the oxidizing agent.For example, it is conceivable to use permanganate.However, when permanganate is used, manganese dioxide can be generated as a reaction product to block the aquifer. That permanganate has high reactivity with organic matter in soil and increases drug consumption; manganese is a substance whose concentration is regulated by the Water Quality Standards of the Water Supply Law, etc. In the present invention, it is particularly suitable to use persulfate or a persulfate as an oxidizing agent, since is higher in toxicity to aquatic organisms than a persulfate. As the persulfate, for example, potassium persulfate, sodium persulfate and the like can be used. The concentration of the injected oxidant in groundwater varies depending on the type of pollutant chemicals and soil properties, but it is generally 10 mg / L or more, especially 50 mg / L or more at the end of the reaction zone (end of the purification range). desirable.
[0017]
The amount of the drug injected from the injection well and the distance between the injection well and the pumping well are adjusted so that the hydraulic residence time of the drug in the reaction region is 2 hours or more, more preferably 12 hours or more. Further, the ratio of the pumping amount to the injection amount may be determined within a range in which there is no leakage of the medicine out of the treatment target area and the diffusion of the medicine occurs efficiently between equal to several times. The injection amount and the pumping amount can be determined by a simulation calculation using, for example, a basic flow equation (continuous equation) of groundwater. In this case, as the parameters used for the above-described simulation calculation, the permeability, the stratum structure, the direction of groundwater flow, the velocity, and the like of the aquifer to be purified are used.
[0018]
The concentration of the drug injected from the injection well (drug concentration in the drug solution) differs depending on the concentration and type of the contaminating chemical substance, and is usually determined by the result of a treatability test using contaminated water at the site. The range is preferably from 100 to 50,000 mg / L, and more preferably from 100 to 50,000 mg / L in consideration of storage of the drug solution. It is also possible to store and inject the drug as a solution in a tank, but if the purification is performed over a long period of time, store it as a solid, create a solution using an automatic drug dissolution device, etc., and continuously inject it. It is also possible.
[0019]
If the pumped groundwater contains pollutant chemicals and a sufficient amount of oxidant remains in the groundwater, decomposition will proceed even if it is left standing for an appropriate period after pumping, and the pollution Although the substances are decomposed, even if the contaminated chemicals contained in the pumped groundwater are decomposed by performing at least one treatment such as aeration treatment, ultraviolet irradiation treatment, and ozone addition treatment on the pumped groundwater. Good. The groundwater treated in this way can be discharged into rivers or sewage.However, a method of adding a chemical to a part or all of this groundwater so as to have a predetermined concentration and re-injecting the same is cost-effective. It is also very effective in terms of system. That is, in the present invention, after adding a chemical to a part or all of the groundwater pumped from the pumping well, the groundwater to which the chemical has been added can be injected again into the soil and the groundwater from the injection well, whereby the unreacted chemical can be obtained. It is possible to reduce the cost by effectively utilizing the groundwater and reusing the pumped groundwater.
[0020]
Groundwater often has a reducing atmosphere, and the groundwater often contains divalent iron ions. When this divalent iron ion comes into contact with air by pumping or is oxidized by an oxidizing agent, it turns into iron oxide and precipitates. In this case, in order to reuse the pumped ground water as water for injection, it is appropriate to remove suspended substances such as iron oxide and fine soil by filtering or coagulating sedimentation.
[0021]
【Example】
Hereinafter, examples performed using the present invention will be described. Note that this example does not limit the scope of the present invention.
[0022]
Using the method of the present invention as a means for purifying soil and groundwater contaminated with trichloroethylene (TCE), a purification test was conducted on site. The area to be purified is a 10m x 10m square, a system that injects oxidant from one injection well located in the center and pumps groundwater from a total of four pumping wells located in four corners. did. In addition, an observation well was installed downstream of the groundwater flow direction and outside the purification target area to confirm whether or not the oxidant had flowed out of the target area.
[0023]
When a simulation was performed using a groundwater flow analysis program (Mod Flow), the result of particle tracking (a method of calculating the recovery rate assuming that the injected substance is particles) showed that the injection flow rate from the injection well was 1 m 3 / hr. On the other hand, a flow rate of 1 m 3 / hr from each pumping well, that is, a total flow rate of 4 m 3 / hr was determined to be optimal. The concentration of the oxidizing agent to be injected was set to 1500 mg / L based on the result of the treatability test using the contaminated groundwater at the site.
[0024]
As a result, the TCE concentration in the groundwater before the purification treatment was 5.2 mg / L, and the TCE concentration in the groundwater three months after the start of the purification treatment was 0.03 mg / L. No oxidizing agent was detected in the observation well during the purification period. Further, the simulation results are shown in reference drawings. According to the reference drawing, it can be seen that TCE in the processing target area is decomposed, and that the oxidizing agent has not leaked out of the processing target area. From the above results, it was confirmed that according to the present invention, soil and groundwater contaminated with chemical substances can be efficiently and safely purified in a short period of time.
[0025]
【The invention's effect】
As described above, according to the present invention, by injecting water or a chemical in situ into soil and groundwater, soil and groundwater can be efficiently purified, and the injected water or chemical can be removed from the treatment target area. Can be recovered from underground without leaking to the underground. Therefore, according to the present invention, soil and groundwater contaminated with chemical substances can be efficiently and safely purified in a short period of time.
[Brief description of the drawings]
FIG. 1 is a diagram showing an arrangement example of an injection well and a pumping well according to the present invention.
FIG. 2 is a diagram showing an example of arrangement of an injection well and a pumping well which does not fall within the scope of the present invention.
[Explanation of symbols]
● Injection well ○ Pumping well
Claims (4)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2002292387A JP3923403B2 (en) | 2002-10-04 | 2002-10-04 | Soil and groundwater purification methods |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2002292387A JP3923403B2 (en) | 2002-10-04 | 2002-10-04 | Soil and groundwater purification methods |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2004122049A true JP2004122049A (en) | 2004-04-22 |
| JP3923403B2 JP3923403B2 (en) | 2007-05-30 |
Family
ID=32283653
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2002292387A Expired - Lifetime JP3923403B2 (en) | 2002-10-04 | 2002-10-04 | Soil and groundwater purification methods |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3923403B2 (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104358267A (en) * | 2014-10-31 | 2015-02-18 | 上海岩土工程勘察设计研究院有限公司 | Vacuum tube well precipitation and disposal method for rapidly restoring in-situ water and soil in polluted place |
| CN104358269A (en) * | 2014-10-31 | 2015-02-18 | 上海岩土工程勘察设计研究院有限公司 | Long/narrow surface well-point dewatering structure for integral polluted water/soil in-situ remediation |
| CN104358268A (en) * | 2014-10-31 | 2015-02-18 | 上海岩土工程勘察设计研究院有限公司 | Linear distribution well-point dewatering structure for integral polluted water/soil in-situ remediation |
| CN104353665A (en) * | 2014-10-31 | 2015-02-18 | 上海岩土工程勘察设计研究院有限公司 | Facet sealed well-point dewatering structure for integrated in-situ polluted water-soil remediation |
| CN104404973A (en) * | 2014-10-31 | 2015-03-11 | 上海岩土工程勘察设计研究院有限公司 | Precipitation method applied to integrated in-situ remediation of polluted water and soil |
-
2002
- 2002-10-04 JP JP2002292387A patent/JP3923403B2/en not_active Expired - Lifetime
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104358267A (en) * | 2014-10-31 | 2015-02-18 | 上海岩土工程勘察设计研究院有限公司 | Vacuum tube well precipitation and disposal method for rapidly restoring in-situ water and soil in polluted place |
| CN104358269A (en) * | 2014-10-31 | 2015-02-18 | 上海岩土工程勘察设计研究院有限公司 | Long/narrow surface well-point dewatering structure for integral polluted water/soil in-situ remediation |
| CN104358268A (en) * | 2014-10-31 | 2015-02-18 | 上海岩土工程勘察设计研究院有限公司 | Linear distribution well-point dewatering structure for integral polluted water/soil in-situ remediation |
| CN104353665A (en) * | 2014-10-31 | 2015-02-18 | 上海岩土工程勘察设计研究院有限公司 | Facet sealed well-point dewatering structure for integrated in-situ polluted water-soil remediation |
| CN104404973A (en) * | 2014-10-31 | 2015-03-11 | 上海岩土工程勘察设计研究院有限公司 | Precipitation method applied to integrated in-situ remediation of polluted water and soil |
| CN104358267B (en) * | 2014-10-31 | 2017-02-01 | 上海岩土工程勘察设计研究院有限公司 | Vacuum tube well precipitation and disposal method for rapidly restoring in-situ water and soil in polluted place |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3923403B2 (en) | 2007-05-30 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6960330B1 (en) | Method for reducing H2S contamination | |
| JP2006346567A (en) | In-situ purification method of contaminated soil | |
| JP4167052B2 (en) | Purification method for organic compound contamination | |
| JP2002159959A (en) | Method and device for purifying underground polluted region | |
| JP2008093575A (en) | Decontamination apparatus and method for decontaminating ground water by using the same | |
| JP2010075887A (en) | Cleaning method of contaminated soil and groundwater | |
| JP4405692B2 (en) | Purification method for underground pollution area | |
| JP4548782B2 (en) | Purification method for organic pollutants | |
| JP3923403B2 (en) | Soil and groundwater purification methods | |
| JP2001347280A (en) | Method for cleaning ground water polluted with halogenated organic compound | |
| JP5612820B2 (en) | Purification method for organic chlorine chemical contamination | |
| JP4095490B2 (en) | Purification method for contamination by chemical substances | |
| JP4702671B2 (en) | In-situ purification method for contaminated soil and contaminated groundwater | |
| JP5528840B2 (en) | Method and apparatus for treating chemical contamination | |
| JP2002136961A (en) | Decontamination method for soil or underground water | |
| JPH10277531A (en) | Method for cleaning contaminated soil by circulation of ground water | |
| JP2012035181A (en) | In situ purification method of contaminated soil and groundwater | |
| JP2000301172A (en) | Method for cleaning soil and/or ground water | |
| JP2002119977A (en) | Method and apparatus for cleaning polluted ground water | |
| JP4024658B2 (en) | Purification method and system for contamination by chemical substances | |
| JP2010075883A (en) | Cleaning method of contaminated soil and groundwater | |
| JP3400942B2 (en) | Method and apparatus for decomposing organic chlorine compounds such as dioxins in landfill leachate | |
| JP2004105870A (en) | Method and apparatus for purification of soil and groundwater | |
| JP3695348B2 (en) | Soil and / or groundwater contaminant treatment agent and method | |
| JP2003181448A (en) | Method and apparatus for treating water polluted with voc |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20050606 |
|
| RD02 | Notification of acceptance of power of attorney |
Free format text: JAPANESE INTERMEDIATE CODE: A7422 Effective date: 20050606 |
|
| RD03 | Notification of appointment of power of attorney |
Free format text: JAPANESE INTERMEDIATE CODE: A7423 Effective date: 20050606 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20061010 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20061017 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20061218 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20070130 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20070221 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 3923403 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100302 Year of fee payment: 3 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110302 Year of fee payment: 4 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110302 Year of fee payment: 4 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120302 Year of fee payment: 5 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120302 Year of fee payment: 5 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130302 Year of fee payment: 6 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130302 Year of fee payment: 6 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20140302 Year of fee payment: 7 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| EXPY | Cancellation because of completion of term |