JP4517593B2 - Water purification jar - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a water purification jar that purifies groundwater contaminated mainly with nitrate nitrogen.
[0002]
[Prior art]
Recently, nitrate nitrogen has become a problem as a harmful pollutant contained in groundwater. Such problems are thought to be caused by the eutrophication of water quality by nitrogen and phosphorus in closed water areas such as lakes and rivers, and as a result, flowing into groundwater in the form of nitrate nitrogen.
[0003]
Nitrate nitrogen is a substance produced as a result of decomposition of nitrogen components in agricultural chemicals, herbicides, fertilizers, manure, etc. by microorganisms, but when nitrate nitrogen enters the body, it is reduced and nitrous acid is added. It changes to natural nitrogen and produces a substance called nitrosamine, which is a carcinogen, or causes so-called methemoglobinemia, which decreases the function of hemoglobin in the blood and causes oxygen deficiency, resulting in cyanosis. Has been pointed out.
[0004]
Therefore, nitrate nitrogen contained in groundwater must be removed in advance so that the concentration is less than the concentration that does not cause health damage.
[0005]
[Patent Document 1]
Japanese Unexamined Patent Publication No. 2000-232728
[0006]
[Patent Document 2]
Japanese Patent Laid-Open No. 10-113693
[0007]
[Patent Document 3]
JP-A-10-286590
[0008]
[Problems to be solved by the invention]
As a method of removing nitrate nitrogen contained in water, attempts have been made to reduce the nitrate nitrogen to nitrogen gas by a plant, and some have already been put into practical use.
[0009]
Here, as a method put into practical use in the plant, there are a sludge sludge method, a dual sludge method, a single sludge method, etc., all of which are hydrogen donors (usually, for reducing nitrate nitrogen in an intermediate step). Methanol) is required separately, or the addition of an alkaline agent that neutralizes the pH is required, and as a result, the reaction process becomes complicated. There was still room for improvement in processing at low cost.
[0010]
In addition to purifying groundwater contaminated with nitrate nitrogen, the development of technology to prevent such a situation from occurring in the first place has also been awaited.
[0011]
The present invention has been made in view of the above-described circumstances, and an object of the present invention is to provide a water purification jar that can efficiently remove nitrate nitrogen contained in groundwater at low cost.
[0012]
Another object of the present invention is to provide a water purification jar capable of preventing nitrate nitrogen produced from agricultural chemicals, herbicides, fertilizers, manure, etc. from penetrating into the ground and flowing into groundwater.
[0013]
[Means for Solving the Problems]
  In order to achieve the above object, the water purification structure according to the present invention is configured such that a hollow space is formed inside a water purification material having denitrification and water permeability as described in claim 1. BecomeA water purification tank, wherein a water-impermeable tube is disposed in the hollow space so that a water guide space is formed between the hollow inner surface of the water purification material and the filter medium is filled in the water-impermeable pipe; The lower part of the filter medium was communicated with the water conveyance space.Is.
[0016]
Moreover, the water purification pad according to the present invention is configured by mixing the water purification material with lime, sulfur and sulfur-oxidizing bacteria.
[0017]
Further, the water purification pad according to the present invention is configured by mixing the water purification material with alkaline waste mud containing hydraulic material, sulfur and sulfur-oxidizing bacteria before solidification of the alkaline waste mud. is there.
[0018]
Further, the water purification pad according to the present invention is a mixture of the water purification material, the waste sludge solidified by alkaline waste mud containing the hydraulic material solidified by the solidification action of the hydraulic material, and sulfur and sulfur-oxidizing bacteria. It is configured as follows.
[0019]
In the water purification tank according to the present invention, the water purification material having a denitrification action and water permeability is configured such that a hollow space is formed therein, or has a denitrification action and water permeability. In addition, a water purification material having air permeability is solidly formed, and a pumping pipe or a drain pipe is inserted into the water purification material.
[0020]
If it does in this way, nitrate nitrogen in water will be reduced to nitrogen gas by the denitrification action of a water purification material.
[0021]
  For example, claims2To claims4In the invention according to the present invention, the water purification material contains sulfur and sulfur-oxidizing bacteria. When the water purification material and water containing nitrate nitrogen come into contact with each other, sulfur in the water purification material is caused by the enzyme activity of the sulfur-oxidizing bacteria. In addition to being oxidized, the sulfur becomes an electron donor along with the oxidation reaction, and nitrate nitrogen in water is reduced to nitrogen gas.
[0022]
Here, sulfur is oxidized by itself to become sulfuric acid, but is neutralized by alkali components in lime and alkaline waste mud. For example, sulfuric acid becomes neutral gypsum by neutralizing with calcium carbonate or calcium hydroxide in lime or alkaline waste mud. For this reason, it is possible to prevent the pH from being reduced by sulfuric acid and prevent the enzyme activity of sulfur-oxidizing bacteria from being lowered. In the case of alkaline waste mud, in the past, it had to be disposed of as industrial waste. However, according to the present invention, there is a remarkable effect that it can be effectively used as a raw material for detoxifying nitrate nitrogen.
[0023]
The problem of nitrate nitrogen contamination is already known in the field of microorganisms at the time of filing of the present application, and the possibility of using sulfur and sulfur-oxidizing bacteria as a method for denitrifying such nitrate nitrogen and sulfuric acid in limestone It is also known that can be neutralized.
[0024]
On the other hand, in the civil engineering and construction industry, a large amount of alkaline waste mud is generated by mud construction methods such as the underground continuous wall construction method, and its disposal becomes a big social problem, and groundwater contaminated with nitrate nitrogen is also removed. When it was used as a water source, development of economically feasible purification technology was awaited. In addition, development of a purification technology that prevents the contaminated water contaminated with nitrate nitrogen from penetrating into the ground and flowing into the groundwater has been awaited.
[0025]
The applicant is concerned with the above-mentioned problem and the social situation where sulfur is surplus in the desulfurization process in gasoline refining etc. As a result of conducting various research and development, we have obtained the above-mentioned new knowledge, and I will add it just in case that the knowledge is extremely significant in the industry.
[0026]
In order for the water purification material to have water permeability or water permeability and air permeability, for example, a method of adjusting components so as to cause cracking, or a method of forming a porous body by adding a foaming agent or the like can be considered. .
[0027]
  When the water purification material is configured so that a hollow space is formed therein, for example, it is configured in a bottomed cylindrical shape, for example, in a bottomed rectangular tube shapeIncludingMu
[0029]
Here, in order to use the water purification tank according to claim 1, the water purification tank is buried near the ground surface so that the top opening of the water purification tank communicates with the atmosphere.
[0030]
In this case, the water purification tank can be used in two ways: a water source tank and an underground infiltration tank.
[0031]
That is, when the surrounding groundwater is contaminated with nitrate nitrogen and the groundwater is to be used as a water source, the water in the hollow space of the water source purification tank is pumped up.
[0032]
The water in the purification basin for the water source is one in which the surrounding groundwater has permeated through the water purification material that constitutes the purification basin for the water source. The action occurs, and nitrate nitrogen contained in the groundwater is reduced to nitrogen gas, and the nitrogen gas is released to the atmosphere through the top opening of the water source purification tank. The pumped water can be used as water from which nitrate nitrogen has been removed.
[0033]
By the way, the environment where the surrounding groundwater is contaminated with nitrate nitrogen includes the environment where groundwater is stored by underground dams and the groundwater is contaminated.
[0034]
On the other hand, when contaminated water containing nitrate nitrogen generated from domestic wastewater, agricultural chemicals, herbicides, fertilizers, manure, etc. is to be infiltrated underground, such contaminated water is put into the hollow space of the underground infiltration septic tank.
[0035]
In this way, the contaminated water in the underground infiltration basin passes through the water purification material constituting the underground infiltration basin and flows out to the surrounding ground. Nitrification occurs, and nitrate nitrogen contained in the contaminated water is reduced to nitrogen gas, and the nitrogen gas is released to the atmosphere through the soil voids. The outflowed water eventually joins groundwater as water from which nitrate nitrogen has been removed.
[0036]
In the water purification tank according to claim 1, an impermeable pipe is disposed in the hollow space so that a water guide space is formed between the hollow inner surface of the water purification material and the impervious pipe is filled with a filter medium. In addition, when the lower part of the filter medium is communicated with the water conveyance space, the treated water from which nitrate nitrogen has been removed by the denitrification action flows through the water conveyance space when used as a water source purification tank, and enters the impermeable pipe. Water is once collected below the filled filter medium.
[0037]
Therefore, the treated water from which nitrate nitrogen has been removed passes through the filter medium from the bottom to the top during pumping, and it is possible to perform not only nitrate nitrogen but also necessary purification as clean water. .
[0040]
That is, when the surrounding groundwater is contaminated with nitrate nitrogen and the groundwater is to be used as a water source, the water in the internal permeable space of the water source purification tub is pumped through the pumping pipe.
[0041]
In this way, as in the invention according to claim 1, the denitrification action described above occurs in the water permeation step, nitrate nitrogen contained in the groundwater is reduced to nitrogen gas, and the nitrogen gas is water purification. It is released to the atmosphere through the internal ventilation space of the material. The pumped water can be used as water from which nitrate nitrogen has been removed.
[0042]
On the other hand, if you want to infiltrate contaminated water containing nitrate nitrogen generated from domestic wastewater, pesticides, herbicides, fertilizers, manure, etc., the internal permeable space in the water purification material through the drainage pipe To send.
[0043]
If it does in this way, like the invention concerning Claim 1, denitrification occurs in a water permeation process, nitrate nitrogen contained in polluted water will be reduced into nitrogen gas, and such nitrogen gas will be Released to the atmosphere through the internal ventilation space. The outflowed water flows out to the surrounding ground as water from which nitrate nitrogen has been removed, and eventually joins the groundwater.
[0044]
  The water purification material has a denitrification action and water permeability, or has a denitrification action and has water permeability and breathability.InAny configuration may be used as long as the configuration includes sulfur and sulfur-oxidizing bacteria as described above.
[0045]
For example, a mixture of lime, sulfur and sulfur-oxidizing bacteria, and alkaline waste mud containing hydraulic material solidified by solidifying action of the hydraulic material, and sulfur and sulfur-oxidizing bacteria It is conceivable that the mixture is constituted by mixing alkaline waste mud containing hydraulic material, sulfur and sulfur-oxidizing bacteria before solidifying the alkaline waste mud. In addition, what is necessary is just to add suitably the enzyme active substance required for the enzyme activity of the sulfur oxidation bacterium which catalyzes sulfur oxidation reaction, for example, a carbon source or organic substance as needed. For example, charcoal, wood, sugarcane residue, waste material, and the like can be considered.
[0046]
Hydraulic materials include cement and lime.
[0047]
Alkaline waste mud containing hydraulic materials is mainly for waste mud produced by underground wall construction methods and mud construction methods such as shields, but for the convenience of transportation, hydraulic materials are added for the purpose of solidification. The waste mud is not limited to the waste mud produced by the muddy water method as long as it is alkaline. The solidifying action of the hydraulic material mainly means a hydration reaction by cement.
[0048]
In addition, when water purification material is constituted by mixing alkaline waste mud containing hydraulic material, sulfur and sulfur oxidation bacteria before solidification of alkaline waste mud, sulfur oxidation bacteria catalyze the oxidation reaction of sulfur. Therefore, it takes a number of days until the microbial activity becomes high, and even if it is added to the alkaline waste mud, the alkaline waste mud solidifies before the oxidation reaction of sulfur starts. Therefore, there is almost no concern that sulfur is oxidized when the water purification structure is constructed.
[0049]
DETAILED DESCRIPTION OF THE INVENTION
  Hereinafter, the water purification tank according to the present inventionReference examples andEmbodiments will be described with reference to the accompanying drawings..
[0050]
(FirstReference example)
[0051]
  Figure 1 shows the bookReference exampleIt is sectional drawing which showed the water purification tank concerning. As shown in the figure,Reference exampleThe water purification tub 1 as the water purification tub according to the present invention is configured such that a hollow space is formed inside the water purification material.
[0052]
As shown in the figure, the water source purification tub 1 has a hollow space 2 inside by forming a water purification material so as to have a bottomed hollow cylindrical shape.
[0053]
The water source purification tub 1 may be manufactured with a water purification material having a denitrification action and water permeability, but can be specifically manufactured by the following three methods.
[0054]
(i) The purification jar 1 for water sources is constituted by mixing lime with sulfur and sulfur-oxidizing bacteria.
[0055]
In this case, a mold that can be formed into a cylindrical shape with a bottom is manufactured in advance, and the lime, sulfur, and sulfur-oxidizing bacteria described above are mixed and added together with water to be solidified. At the time of solidification, water permeability is ensured by appropriately adopting known techniques such as intentionally generating cracks or adding a foaming agent to form a porous structure.
[0056]
(ii) The water source purification tub 1 is configured by mixing the waste sludge solidified by the alkaline waste mud containing cement and solidified by the cement, and sulfur and sulfur-oxidizing bacteria.
[0057]
In this case, a mold that can be formed into a cylindrical shape with a bottom is manufactured in advance, and the solidified sludge and the sulfur and sulfur-oxidizing bacteria described above are charged therein and a solidifying agent for solidifying them, such as cement milk. May be added and solidified. At the time of solidification, water permeability is ensured by appropriately adopting known techniques such as intentionally generating cracks or adding a foaming agent to form a porous structure.
[0058]
(iii) The alkaline waste mud containing cement, which is a hydraulic material, and sulfur and sulfur-oxidizing bacteria are mixed before the alkaline waste mud is solidified to constitute the water purification tub 1.
[0059]
In this case, a mold that can be formed into a bottomed cylindrical shape is manufactured in advance, and the alkaline waste mud described above, sulfur and sulfur-oxidizing bacteria are mixed and charged therein, and solidified. At the time of solidification, water permeability is ensured by appropriately adopting known techniques such as intentionally generating cracks or adding a foaming agent to form a porous structure.
[0060]
In each of the production methods (i), (ii), and (iii) described above, an enzyme active substance, such as a carbon source or an organic substance, necessary for the enzyme activity of sulfur-oxidizing bacteria that catalyze the oxidation reaction of sulfur is used as necessary. What is necessary is just to add suitably. For example, charcoal, wood, sugarcane residue, waste material, and the like can be considered.
[0061]
In order to catalyze the sulfur oxidation reaction by sulfur-oxidizing bacteria, it takes time until the microbial activity becomes high. Therefore, when sulfur and sulfur-oxidizing bacteria are mixed and solidified in lime or alkaline waste mud, In combination with the consumption of water in the hydration reaction, there is almost no concern that the microbial activity is increased and sulfur is oxidized until the water source purification tank 1 is completed.
[0062]
By the way, after installation, since groundwater permeates into the internal water-permeable space of the water purification material constituting the water source purification tub 1, sulfur-oxidizing bacteria oxidize sulfur in the internal water-permeable space and sulfur is Nitrate nitrogen contained in groundwater as an electron donor is reduced and converted to nitrogen gas. Moreover, since the sulfuric acid produced by the oxidation of sulfur is neutralized with an alkaline component derived from lime or cement, the enzyme activity of sulfur-oxidizing bacteria does not decrease.
[0063]
In the case of the production methods (ii) and (iii) using alkaline waste mud, the mixing ratio of alkaline waste mud and sulfur may be, for example, 50 to 90:50 to 10 in weight ratio.
[0064]
The alkaline waste mud that is the raw material should use the waste mud generated by underground continuous wall construction. In underground underground wall construction, when excavating the ground, in order to prevent collapse of the excavated hole wall, excavation is performed while putting muddy water as a stabilizing liquid in the excavation hole. Replace and collect the stable solution while placing.
[0065]
Although this spent stable liquid becomes waste mud, it is replaced and recovered with underwater concrete, so cement is mixed in the waste mud, and therefore, such waste mud becomes alkaline waste mud. Yes.
[0066]
In order to use the water source purification pad 1 manufactured in this way when the surrounding ground water is contaminated with nitrate nitrogen and wants to use the ground water as a water source, as shown in FIG. It is buried near the ground surface of the ground 4 so that the top opening 3 of the gutter 1 communicates with the atmosphere, and the pumping pipe 5 is disposed in the hollow space 2.
[0067]
The embedding depth of the water source purification tub 1 is set to such a depth that the water level of the hollow space 2 of the water source purification tub can be lowered by lowering the water level of the hollow space than the surrounding groundwater level.
[0068]
Here, if the underground water level is low and the embedding depth of the water source purification tub 1 is deepened, and therefore the head is increased, a pump is installed at the bottom of the water source purification basin 1, and the pump It is only necessary to connect the pumping pipe 5 to the pump to pump the water on the ground.
[0069]
In the water source purification tub 1 installed in this way, the surrounding ground water will flow through the water purification material constituting the water source purification tub 1 and flow into the hollow space 2. The nitrate nitrogen in the groundwater is reduced to nitrogen gas by the denitrification action of the purification material.
[0070]
That is, when the water purification material that constitutes the water source purification tank 1 and the groundwater containing nitrate nitrogen come into contact, sulfur in the water purification material is oxidized by the enzyme activity of the sulfur-oxidizing bacteria, and accompanying the oxidation reaction. The sulfur becomes an electron donor, and nitrate nitrogen contained in the ground water is reduced to nitrogen gas, and the nitrogen gas is released to the atmosphere through the top opening of the water source purification tub 1. The pumped water can be used as water from which nitrate nitrogen has been removed.
[0071]
Here, as described above, the sulfuric acid produced by the sulfur oxidation is neutralized by the alkali component in the lime or alkaline waste mud, and the sulfuric acid becomes neutral gypsum. Therefore, it is possible to prevent the pH from being reduced by sulfuric acid and the enzymatic activity of sulfur-oxidizing bacteria from being lowered.
[0072]
As described above, according to the water source purification pad 1 according to the present embodiment, when the water purification material and the groundwater containing nitrate nitrogen come into contact with each other, sulfur in the water purification material is oxidized by the enzyme activity of the sulfur-oxidizing bacteria. Along with the oxidation reaction, the sulfur becomes an electron donor, and nitrate nitrogen in the groundwater is reduced to nitrogen gas.
[0073]
Therefore, nitrate nitrogen contained in groundwater can be efficiently removed at low cost, and the water flowing into the hollow space 2 of the water source purification tub 1 becomes treated water from which nitrate nitrogen has been removed. By pumping this to the ground, it can be effectively used as a water source.
[0074]
On the other hand, sulfur is oxidized by itself to become sulfuric acid, but since it is neutralized by the alkaline components in the alkaline waste mud, it prevents sulfuric acid from reducing the pH and reducing the enzyme activity of sulfur-oxidizing bacteria. Can do.
[0075]
  Alkaline waste mud has a high adsorption capacity for phosphorus.Reference exampleThe water purification material that constitutes the water source purification pad 1 according to the present invention has not only the action of purifying nitrate nitrogen but also the action and effect of adsorbing and removing phosphorus.
[0076]
  Also bookReference exampleAccording to the purification pad 1 for water source according to the present invention, it is possible to effectively use alkaline waste mud that has been conventionally disposed as industrial waste as a raw material for detoxifying nitrate nitrogen. Play.
[0077]
  Also bookReference exampleAccording to the water purification plant 1 according to the above, sulfur that tends to be surplus in the desulfurization step in gasoline refining or the like can be effectively used.
[0078]
  BookReference exampleAlthough not mentioned in particular, if the concentration of nitrate nitrogen is high, the pumped water is not used immediately, but instead it is permeated into the ground.PurificationBy repeating the procedure of pumping water through the fossil 1, it becomes possible to reliably purify the high-concentration groundwater contaminated area.
[0079]
By the way, if the pumping energy in that case is covered by electric energy converted from natural energy such as wind power generation, it is possible to construct an environmental restoration system that can be self-sufficient in terms of energy.
[0080]
(SecondReference example)
[0081]
  FirstReference exampleThen, the water purification material is configured to form a hollow space in the interior to obtain the water source purification rod 1, but instead of this configuration, the water purification having denitrification action and water permeability and air permeability. It is good also as a structure which formed the material in solid.
[0082]
  Figure 2 takes suchReference examplesIt is shown. As you can see in the figure, the bookReference exampleThe water purification tub 1a as a water purification tub according to the above has a water purification material solidly formed and a water pump 11 is inserted into the water purification material.
[0083]
  The water source purification pad 1a may be made of a water purification material having a denitrification action and water permeability and air permeability.Reference exampleIn substantially the same manner, it can be manufactured by the following three methods.
[0084]
(i ') The water source purification waste 1a is constituted by mixing lime with sulfur and sulfur-oxidizing bacteria.
[0085]
In this case, if a mold that can be formed into a solid cylindrical shape is manufactured in advance, the pumping pipe 11 is previously disposed therein, and then the lime, sulfur, and sulfur-oxidizing bacteria described above are mixed with water and solidified. Good.
[0086]
If it does in this way, the pumping pipe 11 will be connected to the internal water-permeable space of a water purification material, and it will become possible to pump the water which permeate | transmitted this water purification material.
[0087]
It is desirable to provide a large number of water-permeable holes 12 in the pumping pipe 11 inserted into the water purification material.
[0088]
In solidification, water permeability and air permeability are ensured by appropriately adopting known techniques such as intentionally cracking or adding a foaming agent to form a porous structure.
[0089]
(ii ′) The water source purification waste 1a is formed by mixing the waste sludge solidified by the solidification action of the alkaline waste sludge containing cement with sulfur and sulfur-oxidizing bacteria.
[0090]
In this case, a mold that can be formed into a solid cylindrical shape is manufactured in advance, and the pumping pipe 11 is previously disposed therein, and then the above-described waste mud solidified body, sulfur, and sulfur-oxidizing bacteria are added to the mold. A solidifying agent for solidification, for example, cement milk, may be additionally charged and solidified. In solidification, water permeability and air permeability are ensured by appropriately adopting known techniques such as intentionally cracking or adding a foaming agent to form a porous structure.
[0091]
(iii ′) The water source purification waste 1a is configured by mixing alkaline waste mud containing cement, which is a hydraulic material, and sulfur and sulfur-oxidizing bacteria before the alkaline waste mud is solidified.
[0092]
In this case, a mold that can be formed into a solid cylindrical shape is manufactured in advance, the pumping pipe 11 is previously disposed therein, and then the above-described alkaline waste mud, sulfur and sulfur-oxidizing bacteria are mixed and charged, and solidified. Just do it. In solidification, water permeability and air permeability are ensured by appropriately adopting known techniques such as intentionally cracking or adding a foaming agent to form a porous structure.
[0093]
In order to use the water source purification tub 1a thus manufactured when the surrounding ground water is contaminated with nitrate nitrogen and wants to use the ground water as a water source, as shown in FIG. It embeds near the ground surface of the ground 4 so that the internal ventilation space of the water purification material which comprises the gutter 1a communicates with air | atmosphere.
[0094]
The burial depth of the water source purification tub 1a is determined by raising the water that has permeated through the internal water permeable space of the water purification material constituting the water source purification basin so that the water level of the internal water permeable space is higher than the surrounding groundwater level. The depth should be as low as possible.
[0095]
In the purification basin 1a for the water source installed in this way, the surrounding groundwater will permeate the water purification material constituting the purification basin and flow into the internal permeable space. The nitrate nitrogen in the groundwater is reduced to nitrogen gas by the denitrification action of the material.
[0096]
That is, when the water purification material that constitutes the water source purification tank 1a and the groundwater containing nitrate nitrogen come into contact, sulfur in the water purification material is oxidized by the enzyme activity of the sulfur-oxidizing bacteria, and accompanying the oxidation reaction. The sulfur becomes an electron donor, and nitrate nitrogen contained in the groundwater is reduced to nitrogen gas. The nitrogen gas passes through the internal ventilation space of the water purification material constituting the water source purification tank 1a. Is released. The pumped water can be used as water from which nitrate nitrogen has been removed.
[0097]
The internal water-permeable space and the internal air-permeable space are shared by a cracked portion and a void portion in the water purification material.
[0098]
  Including the description about microbial activity and alkaline waste mud, the structure, action and effect not particularly described in this embodiment areReference exampleTherefore, the description thereof is omitted here.
[0099]
(ActualEmbodiment)
[0100]
  FirstReference exampleThen, although the water purification material was comprised so that the hollow space 2 might be formed in the inside, it was set as the purification bowl 1 for water sources,In one embodiment of the invention,Instead of such a configuration, a filter medium 24 is arranged in the hollow space 2 as shown in FIG.The
[0101]
  FIG.BookEmbodimentShowIt is a thing. As can be seen in the figure, the water source purification pad 1b as the water purification pad according to the present embodiment is similar to the first embodiment by forming the water purification member so as to have a bottomed hollow cylindrical shape. However, in this embodiment, a water-impermeable tube 23 is arranged in the hollow space 2 so that a water guide space 22 is formed between the hollow inner surface 21 and filtered in the water-impermeable tube. The material 24 is filled, and the lower part of the filter material is communicated with the water guide space 22.
[0102]
Here, the filter medium 24 can be configured by laminating, for example, a carbide layer, a sand layer, a carbide layer, and a gravel layer in the impermeable pipe 23 in this order. The lower end is penetrated.
[0103]
  The water purification tub 1b is the firstReference exampleTherefore, the description thereof is omitted here. The installation method (relative depth relationship with groundwater level) is also the first.Reference exampleTherefore, the description thereof is omitted here.
[0104]
  In the water source purification tub 1b installed in this way, the surrounding ground water will permeate the water purification material of the water source purification basin 1;Reference exampleThe denitrification action described in 1) occurs, and nitrate nitrogen contained in groundwater is reduced to nitrogen gas. Incidentally, if the water guide space 22 is communicated with the atmosphere, the nitrogen gas is smoothly released into the atmosphere through the water guide space.
[0105]
On the other hand, the treated water from which nitrate nitrogen has been removed by the denitrification action flows down the water guide space 22 and is once collected below the filter medium 24 filled in the impermeable pipe 23.
[0106]
Therefore, the treated water from which nitrate nitrogen has been removed will surely pass through the filter medium 24 from the bottom to the top during pumping, and may be purified not only for nitrate nitrogen but also as clean water. It becomes possible.
[0107]
  For other functions and effects, the firstReference exampleIn the above, the description is omitted here.
[0108]
(No.3 Reference examples)
[0109]
  Figure 4 shows the bookReference exampleIt is sectional drawing which showed the water purification tank concerning. As shown in the figure,Reference exampleThe underground infiltration basin 41 as the water purification basin according to the present invention is configured such that a hollow space is formed inside the water purification material.
[0110]
As shown in the figure, the underground infiltration basin 41 has a structure having a hollow space 42 by forming a water purification material so as to have a bottomed hollow cylindrical shape.
[0111]
  The underground infiltration purification tank 41 may be manufactured from a water purification material having a denitrification action and water permeability.Reference example(I), (ii), and (iii) described in (3). Note that the details are redundantly described, and thus the description thereof is omitted here.
[0112]
When the contaminated water containing nitrate nitrogen generated from daily wastewater, agricultural chemicals, herbicides, fertilizers, manure, etc. is to be infiltrated underground using the thus produced underground infiltration slag 41, FIG. As shown in FIG. 2, the top opening 43 of the underground infiltration purifier 41 is buried near the ground surface of the ground 4 so as to communicate with the atmosphere, and the drain pipe 45 is disposed in the hollow space 42.
[0113]
In the underground infiltration basin 41 installed in this way, the contaminated water in the underground infiltration basin will flow through the water purification material and flow out to the surrounding ground. Denitrification occurs, and nitrate nitrogen contained in the contaminated water is reduced to nitrogen gas.
[0114]
That is, when the water purification material constituting the underground infiltration purification tank 41 and the contaminated water containing nitrate nitrogen come into contact, sulfur in the water purification material is oxidized by the enzyme activity of the sulfur-oxidizing bacteria, and the oxidation reaction is performed. Along with this, the sulfur becomes an electron donor, nitrate nitrogen contained in the contaminated water is reduced to nitrogen gas, and the nitrogen gas is released to the atmosphere through the soil gap. The outflowed water eventually joins groundwater as water from which nitrate nitrogen has been removed.
[0115]
Here, as described above, the sulfuric acid produced by the sulfur oxidation is neutralized by the alkali component in the lime or alkaline waste mud, and the sulfuric acid becomes neutral gypsum. Therefore, it is possible to prevent the pH from being reduced by sulfuric acid and the enzymatic activity of sulfur-oxidizing bacteria from being lowered.
[0116]
  As explained above, the bookReference exampleAccording to the underground infiltration purification tank 41 according to the present invention, when the water purification material and contaminated water containing nitrate nitrogen come into contact with each other, sulfur in the water purification material is oxidized by the enzyme activity of sulfur-oxidizing bacteria, and the oxidation reaction thereof. Along with this, the sulfur becomes an electron donor, and nitrate nitrogen in the contaminated water is reduced to nitrogen gas.
[0117]
Therefore, nitrate nitrogen contained in the contaminated water can be efficiently removed at low cost, and the water flowing out from the hollow space 42 of the underground infiltration purifier 41 is treated with the treated water from which nitrate nitrogen has been removed. Therefore, there is no possibility of contaminating the groundwater even if it joins the groundwater.
[0118]
On the other hand, sulfur is oxidized by itself to become sulfuric acid, but since it is neutralized by the alkaline components in the alkaline waste mud, it prevents sulfuric acid from reducing the pH and reducing the enzyme activity of sulfur-oxidizing bacteria. Can do.
[0119]
  Alkaline waste mud has a high adsorption capacity for phosphorus.Reference exampleThe water purification material that constitutes the underground infiltration basin 41 has not only the action of purifying nitrate nitrogen but also the action and effect of adsorbing and removing phosphorus.
[0120]
  Also bookReference exampleAccording to the underground infiltration purification tank 41 according to the present invention, it is possible to effectively use alkaline waste mud that has been conventionally disposed as industrial waste as a raw material for detoxifying nitrate nitrogen. Play.
[0121]
  Also bookReference exampleAccording to the water purification tank 41 according to the above, it is possible to effectively utilize sulfur that tends to be surplus in the desulfurization step in gasoline refining or the like.
[0122]
(No.4 Reference examples)
[0123]
  First3 Reference examplesThen, although the water purification material was comprised so that a hollow space might be formed and it was set as the purification | cleaning trough 41 for underground infiltration, it replaces with this structure, has the denitrification action, and has water permeability and air permeability It is good also as a structure which formed the purification | cleaning material in solid.
[0124]
  FIG.Reference examplesIt is shown. As you can see in the figure, the bookReference exampleThe underground infiltration purifier 41a as the water purifier includes a solid water purification material and a drain pipe 51 penetrating into the water purification material.
[0125]
  The underground infiltration purification tank 41a may be manufactured with a water purification material having a denitrification action and having water permeability and air permeability.3 Reference examplesIn substantially the same manner, it can be manufactured by the following three methods.
[0126]
(i ′) The underground permeation purifier 41a is formed by mixing lime with sulfur and sulfur-oxidizing bacteria.
[0127]
In this case, if a mold that can be formed into a solid cylindrical shape is manufactured in advance, a drain pipe 51 is previously disposed therein, and then the above-described lime, sulfur, and sulfur-oxidizing bacteria are mixed with water and solidified. Good.
[0128]
In this way, the drain pipe 51 communicates with the internal water permeable space of the water purification material, and the contaminated water that has flowed in through the drain pipe 51 is made to permeate the water purification material and then flows out to the surrounding ground. It becomes possible to make it.
[0129]
It is desirable to provide a large number of water permeable holes 12 in the drain pipe 51 penetrating into the water purification material.
[0130]
In solidification, water permeability and air permeability are ensured by appropriately adopting known techniques such as intentionally cracking or adding a foaming agent to form a porous structure.
[0131]
(ii ′) The underground infiltration slag 41a is configured by mixing the waste sludge solidified by the solidification action of the cement-containing alkaline waste sludge with sulfur and sulfur-oxidizing bacteria.
[0132]
In this case, a mold that can be formed into a solid cylindrical shape is manufactured in advance, and a drain pipe 51 is disposed therein in advance, and then the above-described waste mud solidified body, sulfur and sulfur-oxidizing bacteria are added and they are put in place. A solidifying agent for solidification, for example, cement milk, may be additionally charged and solidified. In solidification, water permeability and air permeability are ensured by appropriately adopting known techniques such as intentionally cracking or adding a foaming agent to form a porous structure.
[0133]
(iii ') The underground infiltration slag 41a is constituted by mixing alkaline waste mud containing cement, which is a hydraulic material, and sulfur and sulfur-oxidizing bacteria before solidifying the alkaline waste mud.
[0134]
In this case, a mold that can be formed into a solid cylindrical shape is manufactured in advance, and a drain pipe 51 is previously disposed therein, and then the alkaline waste mud described above, sulfur and sulfur-oxidizing bacteria are mixed and charged and solidified. Just do it. In solidification, water permeability and air permeability are ensured by appropriately adopting known techniques such as intentionally cracking or adding a foaming agent to form a porous structure.
[0135]
When it is desired to infiltrate contaminated water containing nitrate nitrogen generated from domestic wastewater, agricultural chemicals, herbicides, fertilizers, manure, etc. using the underground infiltration slag 41a thus manufactured, FIG. As shown in Fig. 4, the water purification material constituting the underground infiltration purification tank 41a is buried near the ground surface of the ground 4 so as to communicate with the atmosphere.
[0136]
The embedding depth of the underground infiltration purification tank 41a is set to such a depth that the water level of the internal permeable space of the contaminated water flowing in through the drain pipe 51 can be made higher than the surrounding underground water level.
[0137]
In the underground osmosis purification basin 41a installed in this way, the contaminated water will permeate the water purification material constituting the purification basin and flow out to the surrounding surrounding ground. Nitrate nitrogen in the contaminated water is reduced to nitrogen gas by the denitrification action of the purification material.
[0138]
That is, when the water purification material constituting the underground infiltration purification tank 41a and the contaminated water containing nitrate nitrogen come into contact, sulfur in the water purification material is oxidized by the enzyme activity of the sulfur-oxidizing bacteria, and the oxidation reaction is caused. Along with this, the sulfur becomes an electron donor, nitrate nitrogen contained in the contaminated water is reduced to nitrogen gas, and this nitrogen gas is an internal ventilation space of the water purification material constituting the underground infiltration purification tank 41a. Is released to the atmosphere via And the water which flowed out to the surrounding ground will join groundwater as water from which nitrate nitrogen was removed.
[0139]
The internal water-permeable space and the internal air-permeable space are shared by a cracked portion and a void portion in the water purification material.
[0140]
  This book contains information on microbial activity and alkaline waste mud.Reference exampleFor configurations, actions and effects not specifically described in3 Reference examplesTherefore, the description thereof is omitted here.
[0141]
【The invention's effect】
As described above, according to the water purification plant according to the present invention, when the water purification material comes into contact with groundwater or contaminated water containing nitrate nitrogen, sulfur in the water purification material is oxidized by the enzyme activity of sulfur-oxidizing bacteria. At the same time, with the oxidation reaction, the sulfur becomes an electron donor, and nitrate nitrogen in the ground water or contaminated water can be reduced to nitrogen gas to purify the ground water or contaminated water.
[0142]
[Brief description of the drawings]
FIG. 1Reference exampleIt is a figure of the water purification tank which concerns on this, (a) is a vertical sectional view, (b) is a horizontal sectional view which follows an AA line direction.
FIG. 2Reference exampleIt is a figure of the water purification tank concerning this, (a) is a vertical sectional view, (b) is a horizontal sectional view along a BB line direction.
[Fig. 3]One of the present inventionIt is a figure of the water purification tank which concerns on embodiment, (a) is a vertical sectional view, (b) is a horizontal sectional view which follows a CC line direction.
FIG. 43 Reference examplesIt is a figure of the water purification tank which concerns on this, (a) is a vertical sectional view, (b) is a horizontal sectional view which follows a DD line direction.
FIG. 54 Reference examplesIt is a figure of the water purification tank which concerns on this, (a) is a vertical sectional view, (b) is a horizontal sectional view which follows an EE line direction.
[Explanation of symbols]
1,1a, 1b Water source purification tank (water purification tank)
2,42 hollow space
4 ground
5, 11, 25 Pumped pipe
22 Water transfer space
23 Impervious pipe
24 Filter media
41, 41a Underground seepage purification tank (water purification tank)
45,51 Drain pipe

Claims (4)

A water purification jar constructed by forming a hollow space inside a water purification material having denitrification and water permeability ,
An impervious pipe is disposed in the hollow space so that a water guide space is formed between the hollow inner surface of the water purification material, and the water impervious pipe is filled with a filter medium. A water purification plant characterized by communication with space . The water purification jar according to claim 1, wherein the water purification material is configured by mixing lime, sulfur, and sulfur-oxidizing bacteria. The water purification jar according to claim 1, wherein the water purification material is constituted by mixing alkaline waste mud containing a hydraulic material, sulfur and sulfur-oxidizing bacteria before solidification of the alkaline waste mud. 2. The water quality according to claim 1, wherein the water purification material is constituted by mixing waste mud solidified by alkaline waste mud containing hydraulic material solidified by the solidifying action of the hydraulic material, and sulfur and sulfur-oxidizing bacteria. Purification jar.

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