JP6935653B2 - Sulfur material for denitrification - Google Patents

Description

The present invention relates to a sulfur material for denitrification for removing nitrate nitrogen and nitrite nitrogen contained in pig farm wastewater and the like, a denitrification treatment apparatus and a denitrification treatment method using the same.

Nitrate nitrogen (NO ₃ ^-− N) contained in wastewater is known to affect human health and environmental pollution (mainly groundwater pollution). Methemoglobinemia and the like are known as health hazards caused by nitrate nitrogen.

_{In 1999, the total standard value of NO 3} ⁻ -N and nitrite nitrogen (NO ₂ ⁻ −N) was increased to 10 mg / L as an environmental standard item for the protection of human health related to water pollution in groundwater and public water bodies. It was set. However, the excess rate of environmental standards in this groundwater is still high. Causes of groundwater pollution include excessive fertilization, improper treatment of livestock excrement, and underground infiltration of untreated domestic wastewater, and contamination due to livestock excrement is the second highest result after excessive fertilization.

Against this background, the Water Pollution Control Law stipulates the wastewater standards for "ammonia, ammonium compounds, nitrite compounds and nitric acid compounds" contained in wastewater in livestock. The general standard value for this item is 100 mg / L, but in the case of livestock, it is difficult to achieve with conventional treatment techniques, so a provisional standard value of 1500 mg / L was established in 2001. After that, it was reduced to 900 mg / L in 2004, 700 mg / L in 2013, and 600 mg / L in 2016, and in the future, it is required to work on sewage treatment aiming at the general standard value even in livestock. In this specification, "ammonia, ammonium compound, nitrite compound and nitric acid compound" are described as "nitrate nitrogen, etc.", and NO ₃ ⁻ −N and NO ₂ ⁻ −N are collectively referred to. Described as "NOx-N".

Among livestock, especially for pig farming wastewater, nitrogen reduction technology utilizing the sulfur denitrification method has been developed so far. The sulfur denitrification method is a method in which sulfur oxidation denitrification bacteria, which are a type of independent vegetative bacteria such as Thiobacillus denitrificans _{, reduce NO 3} ⁻ −N and NO ₂ ⁻ −N to nitrogen gas while oxidizing sulfur under anoxic conditions. In this method, a sulfur material is used.

However, in the sulfur denitrification method, when powdered sulfur is used as a sulfur material, it cannot be used for wastewater treatment because it has water repellency as it is. It is necessary to add and stir to make it hydrophilic, and there is a problem that this work requires a great deal of labor. On the other hand, if crude sulfur (including coarse particles with a particle size of about 40 mm) that is distributed as an industrial raw material is used instead of powdered sulfur, it will settle in water as it is, so hydrophilization treatment is not required, but per unit weight. Since the contact area of sulfur is small, there is a problem that the denitrification activity is lower than that of powdered sulfur.

Also, the sulfur in the denitrification, although supplementation prevention and denitrification activity of the alkalinity needed to pH drop in the treated water by sulfate ions increases with the progress of the denitrification activity of (SO 4 ^_2-) is determined , There was a risk that the system would be complicated if an addition device was provided to replenish the alkalinity.

In Patent Document 1, as a sulfur material that does not require a separate supplementation of alkalinity, calcium carbonate is uniformly stirred and mixed with heated and melted sulfur to cool and solidify, and the solidified product obtained by this cooling is crushed. A composition in which calcium carbonate and sulfur coexist in a single particle is described as a granular or lumpy solid. However, the composition described in Patent Document 1 has a problem that a special molding process requires a cost and a contact area per unit weight is smaller than that of powdered sulfur, and further improvement is required. ..

Japanese Patent No. 3430364

In view of the above circumstances, it is an object of the present invention to provide a sulfur material for denitrification which has both hydrophilicity and alkalinity replenishment function, can be easily used, has high denitrification performance, and is easy to manufacture. ..

One aspect of the present invention relates to the following matters.

1. 1. Sulfur material for denitrification, including powdered sulfur, alkaline agents, and surfactants.

2. The sulfur material for denitrification according to 1 above, wherein the alkaline agent contains calcium carbonate and / or magnesium carbonate.

3. 3. The sulfur material for denitrification according to 1 or 2 above, wherein the alkaline agent contains natural magnesite and / or synthetic magnesite.

4. The sulfur material for denitrification according to any one of 1 to 3 above, wherein the surfactant contains a nonionic surfactant.

5. The content of the powdered sulfur is 30 to 69.5% by weight, the content of the alkaline agent is 30 to 69.5% by weight, and the surface activity is based on the total weight of the sulfur material for denitrification. The sulfur material for denitrification according to any one of 1 to 4 above, wherein the content of the agent is 0.5 to 5% by weight.

6. The denitrifying sulfur material according to any one of 1 to 5 above, wherein the alkaline agent contains calcium carbonate, and the content of calcium carbonate particles in a 60 mesh pass with respect to the total weight of calcium carbonate is 10% by weight or less.

7. A method for producing a sulfur material for denitrification, which comprises a step of kneading powdered sulfur, an alkaline agent, and a surfactant.

8. A method for denitrifying wastewater, which comprises a step of bringing the sulfur material for denitrification according to any one of 1 to 6 into contact with wastewater.

9. A denitrification treatment apparatus containing the sulfur material for denitrification according to any one of 1 to 6 above.

10. A tank that can hold liquids and
In the tank, the first compartment and the second compartment, which are partitioned by the partition wall in the vertical direction and communicated by the liquid passage space directly below the partition wall,
A sulfur material layer in which the sulfur material for denitrification according to any one of 1 to 6 above is deposited to a height above the liquid passage space in the lower portion in the first compartment, the lower portion in the second compartment, and the liquid passage space. When,
A pressurized air supply pipe that communicates with the vicinity of the liquid passage space and supplies pressurized air to the sulfur material layer in the first section and the sulfur material layer in the second section.
The denitrification treatment apparatus according to 8 above.

11. A tank that can hold liquids and
In the tank, the first compartment and the second compartment, which are partitioned by the partition wall in the vertical direction and communicated by the liquid passage space directly below the partition wall,
Sulfur in which the denitrifying sulfur material according to any one of 1 to 6 above is deposited to a height above the liquid passage space in the lower portion in the first compartment, the lower portion in the second compartment, and the liquid passage space. Material layer and
With the vibrator installed on the outer surface of the tank and / or in the sulfur material layer,
The denitrification treatment apparatus according to 9 above.

12. A tank that can hold liquids and
A sulfur material layer in which the sulfur material for denitrification according to any one of 1 to 6 is deposited in the lower part of the tank, and
A means for supplying a liquid from the outside of the tank into the sulfur material layer,
Have,
9. The denitrification treatment apparatus according to 9 above, wherein the supplied liquid is inverted at the bottom of the layer and becomes an upward flow.

According to one aspect of the present invention, it is possible to provide a sulfur denitrifying material that can be easily used, has high denitrification performance, and is easy to manufacture in a sulfur denitrification method in a pig farm wastewater treatment facility or the like.

It is a schematic diagram which shows one aspect of the denitrification treatment apparatus. It is a schematic diagram which shows another aspect of the denitrification treatment apparatus. It is a schematic diagram which shows another aspect of the denitrification treatment apparatus. It is a schematic diagram of a T-shaped member. It is a schematic diagram of the denitrification treatment apparatus used in an Example. It is a graph which shows the transition of the raw water inflow amount and the hydraulic residence time (HRT) during a test period in an Example. It is a graph which shows the transition of the concentration of _{NO 3} ⁻ −N, NO ₂ ⁻ −N of raw water and treated water during a test period in an Example. It is a graph which shows the transition of the water temperature in a reactor and the NOx-N load amount during a test period in an Example. It is a graph which shows the relationship between the NOx-N load amount and the NOx-N removal rate after the 21st day from the start of a test in an Example. It is a graph which shows the relationship between the water temperature in a reactor and the NOx-N removal rate after the 21st day from the start of a test in an Example. In the embodiment, it is a graph showing the relationship between ΔSO ₄ ^2- and ΔNOx-N. It is a graph which shows the transition of the pH of raw water and treated water during a test period in an Example. It is a graph which shows the transition of the concentration of _{NO 3} ⁻ N with respect to the number of days of denitrification treatment when the type of an alkaline agent is changed in Example (Example B).

<Sulfur material for denitrification>
The denitrifying sulfur material of the present embodiment (also simply referred to as "sulfur material") includes powdered sulfur, an alkaline agent, and a surfactant. Since the sulfur material for denitrification of the present embodiment is in the form of powder, the contact area per unit weight is large, and a high denitrification effect can be obtained. Further, the sulfur material for denitrification of the present embodiment is easily compatible with wastewater because powdered sulfur is coated with a surfactant and has high hydrophilicity, and can be used for denitrification treatment only by adding it to wastewater. Further, since the sulfur material for denitrification of the present embodiment contains an alkaline agent in advance, it is not necessary to separately replenish the alkalinity. Therefore, the sulfur material for denitrification of the present embodiment can be used for denitrification treatment of wastewater very easily. In addition, the sulfur material for denitrification of the present embodiment has a very simple manufacturing method.

In addition, pure sulfur usually falls under the category of dangerous goods (combustibles) under the Fire Service Act, and it is necessary to comply with legally stipulated conditions for transportation, storage, etc. The coexistence of surfactants and alkaline agents makes them nonflammable (that is, they are treated as non-dangerous goods under the Fire Service Act) and are easier to handle than pure sulfur.

Hereinafter, the raw materials and the like contained in the sulfur material for denitrification of the present embodiment will be described in detail. In this specification, the wastewater before the denitrification treatment for removing NOx-N is described as "raw water", and the wastewater after the denitrification treatment is described as "treated water".

(Powdered sulfur)
The particle size of the powdered sulfur contained in the sulfur material for denitrification of the present embodiment is preferably at least 90% by weight or more, preferably 100% by weight of the powdered sulfur in a 150 mesh pass, and the lower limit is not particularly limited. For example, it is preferable that 50% by weight or more is 500 mesh-on. When the particle size of the powdered sulfur is 150 mesh pass, the contact area per unit weight of the sulfur material becomes large, and a high denitrification effect can be obtained. The "particle size" in the present specification is a measurement result based on JIS K6222-1.

The content of powdered sulfur with respect to the total weight of the denitrifying sulfur material is preferably 30% by weight or more, more preferably 40% by weight or more, preferably 70% by weight or less, more preferably 69.5% by weight or less. More preferably, it is 60% by weight or less. When the content of the powdered sulfur is within the range, a sufficient denitrification effect can be obtained, and a sulfur denitrification material having an excellent balance with the effect of the alkaline agent can be obtained.

(Alkaline agent)
The sulfur material for denitrification of this embodiment contains an alkaline agent. Alkaline agent reacts with Sulfate ion (SO 4 ^_2-) which increases with the progress of the denitrification activity of, and prevent a decrease in pH of the treated water to suppress the reduction in denitrification activity properties. As the alkaline agent, a weak alkaline powder is preferable. As the alkaline agent, those capable of maintaining the pH of the treated water preferably at 6.5 to 8.5, more preferably 7.0 to 8.5, and even more preferably 7.2 to 8.5 are preferable.

The alkaline agent is not particularly limited, but for example, sodium hydrogen carbonate (NaHCO ₃ ), sodium carbonate (Na ₂ CO ₃ ), calcium oxide (CaO), calcium hydroxide (Ca (OH) ₂ ), calcium carbonate (CaCO). ₃ ) and magnesium carbonate (MgCO ₃ ). Of these, sodium hydrogen carbonate, calcium carbonate and magnesium carbonate are preferable from the viewpoint of preventing a decrease in pH and supplying carbonate ions necessary for the growth of sulfur-oxidizing denitrifying bacteria and the denitrifying reaction, as one embodiment. Calcium carbonate is more preferable from the viewpoint of low cost.

As one aspect of the present invention, it is preferable to use magnesium carbonate as the alkaline agent. When an alkaline agent containing calcium such as calcium carbonate is used, insoluble calcium sulfate (plaster) is formed in the denitrification reaction, and insoluble components are deposited in the denitrification treatment device (denitrification reactor), so that the sulfur material can be used for a long time. As a result, the material layer may be solidified, causing problems such as a decrease in denitrification ability. On the other hand, magnesium carbonate is preferable for wastewater treatment because it is insoluble in water before the denitrification reaction, and magnesium sulfate formed by the denitrification reaction is easily dissolved in water and an insoluble component is unlikely to be generated. Therefore, the use of magnesium carbonate is less likely to cause the problem of solidification of the material layer as compared with the case of using calcium carbonate, and may be preferable.

As the magnesium carbonate, high-purity magnesium carbonate or magnesite containing magnesium carbonate as a main component is preferable. For example, _{the content of MgCO 3 in} magnesite is preferably 50% by weight or more, more preferably 70% by weight or more, and further preferably 90% by weight or more. Magnesite may be natural magnesite (mineral) or synthetic magnesite. When a sulfur material containing magnesite is used as the alkaline agent, the pH can be maintained at a pH at which the denitrification reaction easily proceeds.

However, as shown in Examples described later, as magnesium carbonate, basic magnesium carbonate (generally, mMgCO ₃ · Mg (OH) ₂ · nH ₂ O (in the formula, m = 3-5, n = 3-8) ), When a magnesium carbonate compound having a hydroxy group is used, the denitrification reaction may not proceed easily, which may not be preferable. The content of the magnesium carbonate compound having a hydroxy group in the alkaline agent is preferably 5% by weight or less, and may be 0% by weight.

These alkaline agents may be used alone or in combination of two or more.

The shape of the alkaline agent is preferably powdery or granular. The average particle size of the alkaline agent (particularly calcium carbonate) is not particularly limited, but 60 mesh-on and 5 mesh paths are preferable, and 50 mesh-on and 5 mesh passes are more preferable.

Further, if the content of fine particles having a small particle size as an alkaline agent is too large, white turbidity may occur in the treated water and a problem may occur in wastewater, and a separate step of precipitating before discharging the treated water is required. In some cases. The preferable particle size of the alkaline agent can be determined by the type of the alkaline agent. For example, if the content of fine particles having a particle size of 60 mesh pass is too large in an alkaline agent (particularly calcium carbonate), white turbidity may occur in the treated water and a problem may occur in drainage. A separate step of precipitating may be required. Therefore, the weight ratio of the particles of the 60 mesh pass to the total weight of the alkaline agent (particularly calcium carbonate) is preferably 10% by weight or less, more preferably less than 5% by weight, and even 0% by weight. good.

The blending amount of the alkaline agent is not particularly limited, but is preferably 30% by weight or more, more preferably 40% by weight or more, and preferably 70% by weight or less, based on the total weight of the sulfur material for denitrification. 5% by weight or less is more preferable, and 60% by weight or less is further preferable.

The compounding ratio (weight ratio) of powdered sulfur and the alkaline agent in the sulfur material for denitrification is not particularly limited, but the ratio (powdered sulfur: alkaline agent) is preferably 3: 7 to 7: 3. It is more preferably 4: 6 to 6: 4, and even more preferably 5: 5. When the compounding ratio is within the range, the balance between the denitrification activity and the suppression of pH decrease is excellent.

(Surfactant)
The sulfur material for denitrification of this embodiment contains a surfactant. The inclusion of a surfactant imparts hydrophilicity to the powdered sulfur, and even if the sulfur material is in powder form, the sulfur material becomes more familiar with wastewater such as pig breeding wastewater, so simply adding this sulfur material into the wastewater Easy to use.

The surfactant is not particularly limited and may be any of nonionic, anionic, cationic and amphoteric, but the main component (preferably 50% by weight or more based on the total weight of the surfactant). It may be 100% by weight), which is preferably a nonionic surfactant. If it is a nonionic type, there is little foaming and it is not easily affected by changes in pH and temperature in the treated water, making it easier to handle sulfur materials. The HLB value of the surfactant is not particularly limited, but is preferably about 10 to 13.

Examples of the nonionic surfactant include polyoxyethylene alkyl ether, polyoxypropylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene distyrene phenyl ether, polyoxyethylene carboxylic acid ester, sorbitan ester, and polyoxy. Examples thereof include ethylene sorbitan ester and acetylene glycol.

Examples of anionic surfactants include alkyl sulfates, polyoxyethylene alkyl ether sulfates, polyoxyethylene alkylphenyl ether sulfates, alkylbenzene sulfonates, {(mono, di, tri) alkyl} naphthalene sulfonates. And so on.

Examples of the cationic surfactant include a quaternary ammonium salt or a pyridinium salt, and specifically, a lauryltrimethylammonium salt, a stearyltrimethylammonium salt, a lauryldimethylethylammonium salt, an octadecyldimethylethylammonium salt and the like. , Dimethylbenzyllaurylammonium salt, cetyldimethylbenzylammonium salt, octadecyldimethylbenzylammonium salt, trimethylbenzylammonium salt, triethylbenzylammonium salt, dimethyldiphenylammonium salt, benzyldimethylphenylammonium salt, hexadecylpyridinium salt, laurylpyridinium salt, dodecyl Examples thereof include pyridinium salt, stearylamine acetate, laurylamine acetate and octadecylamine acetate.

Examples of amphoteric surfactants include carboxybetaine, imidazoline betaine, sulfobetaine, aminocarboxylic acid and the like.

These surfactants may be used alone or in combination of two or more.

When the surfactant and other raw materials are mixed, the surfactant may be diluted with a solvent such as water and used, or may be used as it is without being diluted with a solvent or the like.

The content of the surfactant is preferably 0.5 to 5% by weight, more preferably 1 to 3% by weight, based on the total weight of the sulfur material for denitrification.

The sulfur material for denitrification of the present embodiment is preferably in the form of powder or a mixed form of powder and granules, and as one embodiment, 150 mesh pass of powdered sulfur and 60 mesh on and 5 mesh pass. More preferably, it is a mixture with a powdery and / or granular alkaline agent (particularly calcium carbonate). The sulfur material for denitrification of the present embodiment has a large contact area per unit weight as compared with the conventional sulfur material in the form of coarse crushed or pellets, and can achieve a high denitrification effect.

<Manufacturing method of sulfur material for denitrification>
The method for producing a sulfur material for denitrification of the present embodiment includes a step of kneading powdered sulfur, a surfactant, and an alkaline agent (hereinafter, also simply referred to as "kneading step"). The kneading step can be performed using a known ribbon blender, Henschel mixer, tumbler blender, twin-screw stirrer or the like. In the kneading step, the mixing order of the raw materials is not limited, and all the raw materials may be mixed at the same time, or may be kneaded while being mixed stepwise. The kneading step is not particularly limited, but is preferably carried out under normal temperature and pressure conditions. In this specification, normal temperature means 20 ° C ± 20 ° C (0 ° C to 40 ° C), and normal pressure means pressure that is neither pressurized nor depressurized, and is usually at atmospheric pressure. It means the same pressure (about 1 atm). Further, the kneading step may be carried out using a solvent such as water. The method for producing the sulfur material for denitrification of the present embodiment is a simple method without including a special molding step as described in Patent Document 1.

<Denitrification treatment method>
The sulfur material for denitrification of the present embodiment can be used for removing nitrate nitrogen and the like from wastewater of, for example, livestock industry, agriculture, fishery industry (including aquaculture industry, fish breeding industry, etc.), and in particular. , Suitable for removing nitrate nitrogen and the like from wastewater in the field of livestock industry such as pig farming wastewater. Here, the pig farming wastewater means wastewater containing manure and washing water from the piggery. Sulfur oxidative denitrification bacteria that carry out a sulfur denitrification reaction (a reaction that uses sulfur to reduce nitrate nitrogen or the like to nitrogen gas and at the same time generate sulfate ions) are present in pig farm wastewater. When the sulfur material for denitrification of the present embodiment is used, sulfur-oxidizing bacteria in the wastewater of pigs grow on the surface of the material, and nitrate nitrogen and the like are converted into nitrogen gas by the metabolic reaction, and nitrogen is released to the outside of the system. be able to. Further, the sulfur material for denitrification of the present embodiment can also be used for removing nitrate nitrogen and the like in wastewater treatment of fish breeding water and the like in an aquarium and the like.

The denitrification treatment method of the present embodiment includes a step of bringing the sulfur material for denitrification into contact with wastewater containing nitrate nitrogen or the like such as pig farming wastewater. It is preferable that the sulfur material for denitrification and the wastewater containing nitrate nitrogen or the like are brought into contact with each other in a tank capable of containing a liquid to cause a denitrification reaction.

As one aspect of the present invention, it is preferable to use a denitrification treatment device (also referred to as "denitrification reactor") when performing denitrification treatment of wastewater or the like using a sulfur material for denitrification. The denitrification treatment device is installed, for example, after the pig farming wastewater treatment facility, and denitrifies the discharged water (pig farming wastewater) of the facility.

One aspect of the denitrification treatment device is a tank capable of accommodating a liquid; a first compartment and a second compartment in the tank which are partitioned by a vertical partition wall and communicated by a liquid passage space directly below the partition partition; It is preferable to have a sulfur material layer in which the denitrifying sulfur material is deposited to a height above the liquid passage space in the lower portion in the first compartment, the lower portion in the second compartment, and the liquid passage space. As the denitrification treatment device, a sediment sedimentation separation tank (notch tank) for civil engineering work can be preferably used.

FIG. 1 shows a schematic diagram of an example of a denitrification treatment device. The denitrification treatment device 10 is divided into three compartments (first compartment 10a, second compartment 10b, third compartment 10c) by the vertical partition walls 12a and 12b, and the liquid passage space directly below the partition wall 12a is the first. The first section 10a and the second section 10b communicate with each other. In the lower part of the first compartment 10a, the lower part of the second compartment 10b, and the liquid passage space, there is a sulfur material layer 11 in which the sulfur material for denitrification of the present embodiment is deposited to a height above the liquid passage space. do. Although the sulfur material for denitrification of the present embodiment is in powder form, it contains a surfactant in advance and is hydrophilic, so that it is directly put into the denitrification treatment apparatus 10 without performing a separate hydrophilic treatment. Can be done. The sulfur material 11 for denitrification is not particularly limited, but for example, 100 to 250 kg is charged per notch tank having an effective volume of 500 L.

In the denitrification treatment, raw water 1 such as pig farming wastewater flows into the first section 10a and naturally flows down to the third section 10c. The liquid passes through the sulfur material layer 11 during the flow, and at this time, nitrate nitrogen and the like are changed to nitrogen gas by the sulfur denitrification reaction, and the liquid is discharged to the outside of the system.

Raw water is continuously charged, for example, with an inflow of 100 to 1500 mL / min and a hydraulic residence time (HRT) of 0.2 to 3.5 days per effective volume of water. Sulfur oxide denitrifying bacteria grow on the surface of the sulfur material for denitrification in the sulfur material layer 11 in the tank, and denitrification using sulfur proceeds. Sulfur oxidative denitrification bacteria use sulfur to reduce nitrate nitrogen and the like to nitrogen gas and at the same time generate sulfate ions. Here, since the sulfur material for denitrification of the present embodiment contains an alkaline agent, it is possible to prevent the pH of the treated water from dropping without adding an alkaline agent such as calcium carbonate separately. If necessary, an alkaline agent such as calcium carbonate may be further charged into at least one compartment selected from the first compartment 10a, the second compartment 10b and the third compartment 10c in the denitrification reactor, and may be charged into a plurality of compartments. May be done.

The number of sulfur material input compartments partitioned by the partition wall is shown in FIG. 1 as two compartments, the first compartment 10a and the second compartment 10b, but the number of compartments is further increased, preferably three compartments. , More preferably, the processing performance can be improved by increasing the number of stages to 4 or more sections.

The sulfur material layer for denitrification at the bottom of the denitrification treatment device (for example, an upper open type water tank divided into multiple sections by a partition wall (baffle) having a drainage flow gap at the bottom) gradually increases the liquid passage resistance due to compaction. However, the water level in the upstream section (first section 10a) may rise and eventually overflow the upper part of the partition wall 12a. When overflow occurs, the raw water flows out of the tank of the denitrification treatment device without passing through the sulfur material layer 11, and the denitrification effect is significantly reduced. As one aspect for solving this problem, a material layer having increased water flow resistance is formed by increasing the water level difference between the upstream section 10a and the downstream section (preferably 25 cm, more preferably 50 cm, still more preferably 75 cm). It is preferable to allow the liquid to permeate and pass through. Further, by adjusting the amount of the sulfur material input to the denitrification treatment apparatus, the layer of the sulfur material layer 11 is prevented so that the water level does not rise more than the set water level difference and the liquid to be treated does not overflow the partition wall 12a. It is also preferable to adjust the thickness.

As another aspect of preventing raw water from overflowing the upper part of the partition wall 12a in the denitrification treatment apparatus, it is preferable to periodically release the consolidation of the sulfur material layer, for example, a perforated pipe (for example, a perforated pipe). A method of arranging a perforated PVC pipe) on the entire bottom surface and supplying air with a blower can be mentioned. It was insufficient to release and prevent overflow. Therefore, the present inventors have conducted diligent studies to solve this problem, and the denitrification treatment device is partitioned by a vertical partition wall in the tank; in the tank, and is directly under the partition wall. Sulfur material for denitrification is deposited up to a height above the liquid passage space in the first compartment and the second compartment communicated by the liquid space; in the lower part in the first compartment, the lower part in the second compartment, and the liquid passage space. Sulfur material layer; by having a pressurized air supply pipe that communicates with the vicinity of the liquid passage space and supplies pressurized air to the sulfur material layer in the first section and the sulfur material layer in the second section. It was found that the compaction of 11 can be released.

FIG. 2A shows a schematic view of an example of a denitrification treatment device excellent in releasing the consolidation of the sulfur material layer.

The denitrification treatment device 20 further includes a compressor 21 and a pressurized air introduction pipe 23 in the configuration of the denitrification treatment device 10 of FIG. 1 described above. The pressurized air introduction pipe 23 communicates with the vicinity of the liquid passage space directly below the partition wall 12a, and its end is connected to the T-shaped member 24 which is an air blowing member in the vicinity of the liquid passage space. The denitrification treatment device 20 may further include a solenoid valve 22 on the pressurized air introduction pipe 23 to adjust the inflow of pressurized air from the compressor 21.

As shown in FIG. 3, the T-shaped member 24 has a horizontal bar portion 24a and a vertical bar portion 24b vertically connected to the central portion thereof, and the three ends are open to form a continuous space inside. .. The vertical bar portion 24b of the T-shaped member 24 is connected to the pressurized air introduction pipe 23, and one of the two ends of the horizontal bar portion 24a of the T-shaped member 24 is in the first section 10a and the other end is in the first section 10a. It is preferably located in the second compartment 10b and fixed near the bottom of the denitrification reactor 20 so that the length direction of the horizontal bar portion 24a is substantially perpendicular to the wall surface of the partition wall 12a. The size of the T-shaped member 24 is not particularly limited, but for example, when the total capacity of the denitrification treatment device is ^{about 2 m 3} , the lengths of the horizontal bar portion and the vertical bar portion are 3 to 10 cm, respectively, and the inside The diameter of the hole is preferably about 3 to 10 mm.

In the denitrification treatment device 20, the air pressurized by the compressor 21 passes through the pressurized air introduction pipe 23 and enters the first section and the second section from both ends of the horizontal bar portion 24a of the T-shaped member 24. Is injected into the sulfur material layer (spouted air 4), and the compression of the sulfur material layer is released. The injection time and frequency of the injection of the pressurized air are not particularly limited, but may be set to, for example, 3 to 6 seconds per time, and the number of times may be set to 1 to 4 times a day in the pressurized air introduction pipe 23. The solenoid valve 22 installed in the above may be controlled by a timer.

The denitrification treatment device 20 may include any one of the compressor 21, the solenoid valve 22, the pressurized air introduction pipe 23, and the T-shaped member 24, if necessary, and at least two T-shaped members 24. It is preferable to prepare the above. When two T-shaped members 24 are installed, for example, the T-shaped members 24 are connected to the two ends of the T-shaped branched pressurized air introduction pipes, and the two T-shaped members 24 are connected to the denitrification reactor 20 respectively. It may be fixed near the bottom.

Further, the denitrification treatment apparatus is periodically equipped with a stirrer in which a stirrer is positioned at the bottom height of the sulfur material layer as another embodiment of the deconsolidation method which replaces or is used in combination with the above-mentioned deconsolidation by pressure air. Alternatively, it may be continuously stirred at a slow speed.

In yet another embodiment, the denitrification treatment device is provided by installing a submersible pump under the water surface in the final compartment (third compartment 10c) and discharging the sucked liquid to the vicinity of the material layer under the partition wall through an introduction pipe. Layer compaction can be reduced. At this time, if a short-circuit flow path is formed in the sulfur material layer, the denitrification treatment of the raw water becomes insufficient, so the liquid discharge position, discharge direction, and discharge flow rate are adjusted to be appropriate. Is preferable.

The denitrification treatment device 20 may further provide a means for arranging a perforated pipe (for example, a perforated PVC pipe) on the entire bottom surface and supplying air with a blower to release the consolidation of the sulfur material layer.

In the present embodiment, a plurality of the above-mentioned methods may be used in combination in order to release the consolidation in the denitrification treatment apparatus.

On the other hand, when the sulfur material layer is deconsolidated as described above, if the air flow rate is too high, a tunnel-like void is generated in the material layer of the liquid passage space under the partition wall 12a, and the liquid permeates the material layer. In some cases, the denitrification performance may deteriorate due to the flow down. As one aspect for preventing this, an air blowing member may be installed at the bottom portion of the lower portion of the partition wall 12a at a position away from the liquid passage space, and the sulfur material may be periodically blown back to the lower portion of the partition wall.

FIG. 2B shows an aspect of a denitrification treatment device capable of preventing the formation of tunnel-shaped voids in the material layer of the liquid passage space when the sulfur material layer is deconsolidated. The denitrification treatment device 30 of FIG. 2B is provided with two gradients 31 on the bottom surface of the denitrification treatment device of FIG. 2A. A T-shaped member is provided by providing a gradient 31 on the left and right (first compartment 10a and second compartment 10b) tank bottom surfaces of the lower portion of the partition wall 12a during the denitrification treatment 30 so that the portion directly below the partition wall 12a is the deepest portion of the recess. The sulfur material that has been blown up by the ventilation from 24 can be settled while being guided by the gradient 31, and can naturally return to the state of being deposited on the lower part of the partition wall.

The denitrification treatment device may include a vibrator (not shown). The vibrator constantly or periodically vibrates the sulfur material layer in order to prevent nitrogen bubbles generated from the surface of the sulfur material for denitrification from being embedded in the sulfur material layer and hindering contact between the sulfur material and raw water. In addition to being able to defoam, it also releases the tightness of the sulfur material layer and prevents the formation of a short-circuit flow flow path. The vibrator is arranged on the outer surface of a denitrification treatment device such as a notch tank and / or in a sulfur material layer by a vibrator, a knocker, or the like, for example, a pneumatic type or an electric type.

The denitrification treatment apparatus may further include means (heating means) for heating the liquid temperature in the sulfur material-containing tank (first compartment 10a and second compartment 10b), whereby sulfur oxidation denitrification in the low temperature period may be provided. It is possible to denitrify from pig farm wastewater throughout the year by suppressing the decrease in denitrification activity due to nitrogenous bacteria. The liquid temperature in the tank of the denitrification reactor is preferably 10 to 40 ° C, at which sulfur oxide denitrifying bacteria can act, and more preferably 30 to 40 ° C.

An aspect of the denitrification treatment device provided with the above heating means will be described below. A circulation line in which a submersible pump is installed as a circulation pump in the final section (most downstream section) of the denitrification treatment device, and a part of the liquid (circulating liquid) in the final section is returned to the first section (upstream section). Is provided, and a heating means is provided on this circulation line. For example, in the denitrification treatment apparatus of FIG. 1, a submersible pump is installed in the third compartment 10c, and a circulation line connected to the submersible pump is introduced from the liquid discharge port at the end to the inside of the first compartment 10a via a heating means. It is installed so that the circulating fluid can be discharged. As a result, a part of the liquid in the third compartment 10c is supplied into the first compartment 10a in a heated state, and the decrease in denitrification activity can be suppressed.

As a heating means, for example, an existing pig farming wastewater treatment facility is provided with an aeration tank for subjecting pig farming wastewater to an activated sludge method, and a method of utilizing the heat of the liquid in the aeration tank is preferable. In the aeration tank, a high water temperature (for example, 15 ° C. or higher even in winter) is often maintained throughout the year due to the heat of the blower and the underground temperature. As one aspect, a part of the circulation line is made of, for example, a stainless steel flexible pipe for water supply having a length of about 5 to 10 m (preferably 10 m), wound in a coil in the liquid in the aeration tank, and immersed in the circulating liquid. It is preferable to heat. As a result, the liquid temperature in the aeration tank can be transferred to the denitrification device, and a constant water temperature can be maintained even in winter. Further, if the liquid discharge port of this circulation line is installed near the liquid passage space in the first section of the denitrification treatment device (in the case of the device of FIG. 1 in the first section 10a), the sulfur material is heated at the same time. It is also preferable that the layer can be released from compaction.

As one aspect of this embodiment, two or more denitrification reactors as shown in FIGS. 1, 2A, or 2B may be arranged in series or in parallel.

As another aspect of the denitrification treatment device, a tank capable of containing a liquid; a sulfur material layer in which a sulfur material for denitrification is deposited in the lower part of the tank; and a liquid from outside the tank into the sulfur material layer. An upward flow type denitrification treatment device (denitrification reactor) having a means for supplying is preferable. A schematic diagram of an example of the upward flow type denitrification treatment device is shown in FIG.

The denitrification treatment apparatus of FIG. 4 has a columnar tank 41 capable of accommodating a liquid, a sulfur material layer 42 in which a sulfur material is deposited in the lower part of the tank 41, and raw water from outside the tank in the sulfur material layer 42. The raw water supply pipe 43 for supplying the water is provided. It is preferable that one end of the raw water supply pipe 43 is arranged in the sulfur material layer 42, and the end of the raw water supply pipe 43 in the sulfur material layer is near the bottom, for example, the height of the sulfur material layer 42 from the bottom surface of the tank 41. Sulfur is preferably arranged at a position of 1/2 or less, more preferably 1/4 or less. The shape of the tank 41 of the denitrification treatment device is not limited to a cylindrical shape, and may be, for example, a square shape having a rectangular bottom surface. Further, the size of the tank 41 is not limited to the numbers shown in FIG. 4, and for example, in the case of a cylindrical type, in an actual wastewater treatment facility or the like, the diameter of the bottom surface may be about 50 cm to 4 m, and the height is high. , It may be about 150 cm to 3 m. The amount of the sulfur material is not particularly limited, but for example, 200 g to 600 g is charged per 1 L of the volume of the tank 41.

A plurality of raw water supply pipes 43 may be provided. Further, the end of the raw water supply pipe 43 on the side where the raw water flows in and / or the end on the side where the raw water is discharged may be branched.

In the denitrification treatment apparatus of FIG. 4, raw water is continuously supplied in a downward flow by the raw water supply pipe 43. The method of supplying raw water is not particularly limited, but it may be supplied by a pump or the head difference may be used. The raw water released into the sulfur material layer 42 reverses at the bottom of the tank 41 and becomes an upward flow, and while the raw water passes through the sulfur material layer 42, nitrate nitrogen and the like in the raw water are released by the sulfur denitrification reaction. It changes to nitrogen gas and is discharged to the outside of the system as treated water. Here, in this denitrification treatment device, if a short-circuit flow path is formed, the denitrification treatment of raw water becomes insufficient. Therefore, for example, pressurized air from the raw water supply pipe 43 is required. Is also preferably inserted into the sulfur material layer 42 to homogenize the sulfur material layer.

As one aspect of this embodiment, two or more upward flow type denitrification treatment devices as shown in FIG. 4 may be arranged in series or in parallel.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

<Example A>
(1) Sulfur material for denitrification Based on sulfur powder (sulfur 99.5%, 150 mesh pass), calcium carbonate (30 mesh pass and 50 mesh on), and a nonionic surfactant (parent oil) whose viscosity has been adjusted. The HLB value of 12.8) with 22 carbon atoms of the group was kneaded using a ribbon blender or a twin-screw stirrer to produce a sulfur denitrifying material 1 (hereinafter, also simply referred to as “sulfur material 1”). The blending ratio of each raw material is 48.5% by weight of powdered sulfur, 48.5% by weight of calcium carbonate, and 3% by weight of nonionic surfactant. Sulfur material 1 contains 150 mesh pass sulfur and 30 mesh pass and 50 mesh. It was in the form of a powder containing on calcium carbonate.

(2) Experimental equipment As the denitrification reactor, a cylindrical plastic column (about 8 cm φ × about 48 cm H) having an effective volume of 2.23 L in the liquid part shown in FIG. 4 was used. 1 kg of the developed sulfur material 1 (apparent volume 1.12 L, layer thickness 22.7 cm) was put into this denitrification reactor. Activated sludge treated water discharged from a sewage treatment facility of a pig farmer was used as the raw water for the test. However, after the 23rd day of the test, due to epidemic prevention problems, it was not possible to enter the farm, so 2.0 g / L of sodium nitrate was added to the activated sludge treated water of the Chiba Prefectural Livestock Research Center for the test. It was made into raw water. The raw water is transferred to a raw water storage tank, from which the inflow volume is 1.0 to 6.5 mL / min by a diaphragm metering pump, and the hydraulic residence time (HRT) per effective volume of the liquid part is 0.2 to 1.5 days. Continuous injection was performed from the lower part of the (Fig. 5). The effect on denitrification activity was investigated by varying _{the NO x} −N load by adjusting the inflow of raw water. The injected raw water passed through the sulfur material layer deposited on the bottom surface of the reactor and then discharged as treated water from the upper part of the reactor. In order to keep the temperature of the raw water constant, a submersible heater was put into the raw water storage tank from the 7th day after the start of the test to adjust the water temperature to about 20 ° C. Sulfur oxide denitrifying bacteria were not planted. The reactor was operated for 62 days from November 18, 2015 to January 19, 2016.

(3) Analytical method The pH was measured by the glass electrode method. NO ₃ ⁻ −N, NO ₂ ⁻ −N, ammonium nitrogen (NH ₄ ⁺ −N), and SO ₄ ^2- can be prepared by the chromotropic acid method, diazotization method, salicylic acid method, and barium sulfate / turbidimetry method, respectively. It was measured by an absorbance type multi-item water quality measuring instrument (PhotoFlex STD; Central Kagaku Corp., Tokyo). M-alkalinity was measured by a drop test M-alkalinity (WAD-AL-M; Kyoritsu Institute of Physical and Chemical Research, Tokyo).

Table 1 shows the water quality properties of raw water and treated water. The water quality in Table 1 represents the average value during the treatment period in the denitrification reactor.

When the sulfur material 1 was put into a denitrification reactor filled with a liquid, it was confirmed that the entire amount settled quickly. Immediately after sedimentation, cloudiness was observed in the liquid in the reactor, but it gradually faded over time. _{The NO 3} ⁻ -N of the raw water during the test period was 207.7 ± 53.1 mg / L (mean ± standard deviation), and NO ₂ ⁻ −N and NH ₄ ⁺ −N were hardly detected (Table 1). ).

_{NO 3} ^- N of treated water began to decrease after the 16th day of the start of the test, and on the 19th day, it decreased to 100 mg / L or less, which is the general standard value for nitrate nitrogen, etc. of the Water Pollution Control Law (Fig. 6). .. After the 23rd day, NO ₃ ⁻ -N in the treated water was below the detection limit. After that, it was possible to maintain 100 mg / L or less until the 62nd day when the test was completed. The water temperature during the test period varied from 12.6 to 22.7 ° C, with an average of 18.6 ° C (Fig. 7). The NOx-N load varied in the range of 0.28 to 1.95 kg-N / ton-materials / day (Fig. 7). In particular, after the 21st day after the onset of denitrification activity, the NOx-N loading amount was gradually increased in the range of 0.28 to 0.91 kg-N / ton-materials / day with the elapsed days. As a result, in the 62 days NOx-N load 0.91 kg-N / ton-material-date, the treated water _NO ³ - -N is increased to 44.4mg / L, NOx-N removal rate A high denitrification effect was maintained even when the load increased to 83.1%. In addition, regarding the relationship between the NOx-N load and the NOx-N removal rate after the 21st day, the lower the load, the higher the removal rate tended to be (FIG. 8). It has been reported that a removal rate of about 80% was obtained using pure powdered sulfur under the conditions of NOx-N load 0.55 kg-N / ton-materials and days (Teruaki Hasegawa, Yasuo Tanaka (Terukiaki Hasegawa, Yasuo Tanaka). 2015) Development of sulfur denitrification treatment technology for pig farming wastewater by a sediment sedimentation separation tank conversion reactor equipped with a simple heating system: Journal of the Japan Livestock Environment Society: 14 (1): 47-55.), 0. A removal rate of nearly 100% was obtained even at 57 kg-N / ton-materials / day or less. Regarding the relationship between the water temperature and the NOx-N removal rate after the 21st day, it was shown that the higher the water temperature, the higher the removal rate (Fig. 9). Therefore, it is presumed that the denitrification activity increases as the water temperature rises.

Sulfur denitrification process, the sulfur is oxidized by sulfur oxide denitrifying bacteria with the denitrification SO ₄ ^2-is produced. SO ₄ ^2-generation amount (△ _SO ^{4 2-)} and nitrogen removal amount in relation (△ NOx-N) and the removal amount as increases △ _SO ^{4 2-also} tends to increase, a high correlation Shown (R ² = 0.9825, P <0.01) (FIG. 10).

Usually, △ pH of the treated water and _SO ^{4 2-is} increased biased acidic. PH of the treated water and SO ₄ ^2--S reaches about 1000 mg / L is known to be reduced to near 5.8. In this test, the pH of the raw water was 7.5 to 8.3, while the pH of the treated water was in the range of 6.8 to 7.9 (Table 1, FIG. 11). △ SO ₄ ^2-despite increased significantly, pH of treated water was shown to be maintained at approximately neutral. It is presumed that this neutralizing effect also contributed to the formation of calcium sulfate by combining calcium carbonate mixed with the sulfur material for denitrification with sulfate ions.

In addition, alkalinity is an important factor for maintaining denitrification activity in sulfur denitrification treatment. The M-alkalinity of the treated water during the test period was 160 ± 38.4 mg / L (Table 1), but it can be said that the amount of calcium carbonate blended was sufficient because sufficient denitrification activity was exhibited.

From the above results, it was shown that the sulfur material for denitrification of the present embodiment is easy to handle and is effective for supplying and neutralizing the alkalinity required for sulfur denitrification.

In a fact-finding survey of nitrate nitrogen, etc. at a pig farming sewage treatment facility in Chiba Prefecture, it was reported that the average _{NO 3} ^{− -N of activated sludge treated water was 184 mg / L.} On the other hand, in this test, NOx-N decreased by about 200 mg / L after 21 days after the start of the test. From this, it is considered that we can expect measures to reduce nitrate nitrogen, etc. at the site.

<Example B>
Next, the alkaline agent used for the sulfur material was examined.

(Example B1)
Using the activated sludge treated water of a pig farmer as the raw water for the test, 900 mL was put into a beaker having a capacity of 1 L, and 450 g of the above sulfur material 1 (using calcium carbonate as an alkaline agent) was filled therein. The raw water and the sulfur material 1 were stirred and mixed with a glass stirring rod, and then allowed to stand. Subsequently, the pH and NO ₃ ⁻ -N concentration with the elapsed days were measured by the analysis method of Example A above. The test period was 54 days from September 1st to October 25th, 2017. The pH of the treated water with the elapsed days is shown in Table 2, and the NO ₃ ⁻ -N concentration is shown in FIG.

(Example B2)
Sulfur material 2 was prepared in the same manner as in the method for producing sulfur material 1, except that natural magnesite (particle size: 60 mesh pass, 200 mesh on) was used instead of calcium carbonate as the alkaline agent. Raw water was treated in the same manner as in Example B1 except that the sulfur material 2 was used instead of the sulfur material 1, and the pH and NO ₃ ⁻ -N concentration were measured. The results are shown in Table 2 and FIG.

(Example B3)
The sulfur material 3 was prepared in the same manner as the method for producing the sulfur material 1 except that synthetic magnesite (particle size: 150 mesh pass) was used instead of calcium carbonate as the alkaline agent. Raw water was treated in the same manner as in Example B1 except that the sulfur material 3 was used instead of the sulfur material 1, and the pH and NO ₃ ⁻ -N concentration were measured. The results are shown in Table 2 and FIG.

(Reference example B4)
Sulfur material 4 was prepared in the same manner as in the method for producing sulfur material 1, except that basic magnesium carbonate (particle size: 200 mesh pass) was used instead of calcium carbonate as the alkaline agent. Raw water was treated in the same manner as in Example B1 except that the sulfur material 4 was used instead of the sulfur material 1, and the pH and NO ₃ ⁻ -N concentration were measured. The results are shown in Table 2 and FIG.

(Reference example B5)
Sulfur material 5 was prepared in the same manner as in the method for producing sulfur material 1, except that granular basic magnesium carbonate was used as the alkaline agent instead of calcium carbonate. Raw water was treated in the same manner as in Example B1 except that the sulfur material 5 was used instead of the sulfur material 1, and the pH and NO ₃ ⁻ -N concentration were measured. The results are shown in Table 2 and FIG.

In Examples B1 to B3 and Reference Examples B4 and B5, the pH at each denitrification treatment day is shown in Table 2.

In Examples B1 to B3 and Reference Examples B4 and B5, _{the concentration of NO 3} ^-− N in each denitrification treatment day is shown in FIG.

_{As shown in FIG. 12, the concentration of NO 3} ^-− N in the raw water (before the denitrification treatment) was 236.8 mg / L. After the start of the test, _{the concentration of NO 3} ^-− N decreased in each Example and Reference Example, and the concentration of NO ₃ ^-− N and the removal rate on the 54th day were as follows.
Example B1: 7.2 mg / L (removal rate 97%)
Example B2: 5.4 mg / L (removal rate 97.7%)
Example B3: 60.4 mg / L (removal rate 74.5%)
Reference example B4: 145.6 mg / L (removal rate 38.5%)
Reference example B5: 221.6 mg / L (removal rate 6.4%)

From Examples B1 to B3, it was shown that the sulfur material using natural magnesite or synthetic magnesite as the alkaline agent also has a high removal rate of _{NO 3} ^{-−N as in the case of using calcium carbonate.} On the other hand, in the sulfur material using basic magnesium carbonate, the removal rate of _{NO 3} ^{-−N was low.} The reason for this is not clear, but it is presumed that the use of a sulfur material containing natural magnesite or synthetic magnesite was able to maintain a pH at which the denitrification reaction was likely to proceed.

When a sulfur material containing calcium carbonate is used, an insoluble component (calcium sulfate) formed by the denitrification reaction may be deposited, which may interfere with the denitrification treatment. On the other hand, when a sulfur material containing magnesite is used as in Examples B2 and B3, the main component of magnesite is magnesium carbonate, and magnesium sulfate formed by the denitrification reaction is easily dissolved in water, so calcium carbonate. The problem of deposition of insoluble components as in the case of using is less likely to occur.

Therefore, it can be said that a sulfur material containing natural magnesite or synthetic magnesite as an alkaline agent is preferable from the viewpoint of having a high denitrification effect and less likely to generate an insoluble component.

The present invention can be used for removing nitrate nitrogen and the like in pig farm wastewater treatment facilities and the like.

1: Raw water 2: Treated water 3: Pressurized air 4: Ejected air 10: Denitrification treatment device 10a: First compartment 10b: Second compartment 10c: Third compartment 11: Sulfur material layer 12a: Partition 12b: Partition 20: Denitrification treatment device 21: Compressor 22: Solenoid valve 23: Pressurized air introduction pipe 24: T-shaped member 24a: Horizontal bar portion 24b: Vertical bar portion 30: Denitrification treatment device 31: Gradient 41: Tank 42: Sulfur material layer 43: Raw water supply pipe

Claims (16)

Powdered sulfur, A alkali agent containing magnesite, and a surfactant, de窒用sulfur were material (excluding de窒用sulfur material which is integrated with a water-insoluble or sparingly soluble in the binder). It said magnesite comprises natural Magunesai bets, de窒用sulfur material according to claim 1. The sulfur material for denitrification according to claim 1 or 2 , wherein the surfactant contains a nonionic surfactant. The content of the powdered sulfur is 30 to 69.5% by weight, the content of the alkaline agent is 30 to 69.5% by weight, and the surface activity is based on the total weight of the sulfur material for denitrification. The sulfur material for denitrification according to any one of claims 1 to 3 , wherein the content of the agent is 0.5 to 5% by weight. The sulfur material for denitrification according to any one of claims 1 to 4, wherein the average particle size of the alkaline agent is 200 mesh-on. Powdered sulfur, A alkali agent containing magnesite, and integral surfactants, comprising the step of kneading, de窒用sulfur material manufacturing how (where the powdered sulfur and the alkali agent with a water-insoluble or sparingly soluble binder Does not include the process of conversion). A method for denitrifying wastewater, which comprises a step of bringing the sulfur material for denitrification according to any one of claims 1 to 5 into contact with waste water. A denitrification treatment apparatus containing the sulfur material for denitrification according to any one of claims 1 to 5. A tank that can hold liquids and
In the tank, the first compartment and the second compartment, which are partitioned by the partition wall in the vertical direction and communicated by the liquid passage space directly below the partition wall,
Lower portion of the first compartment, a second at the bottom and the liquid passing space in the compartment, sulfur material layer removal窒用sulfur material is deposited to a height of above the liquid passing space,
A pressurized air supply pipe that communicates with the vicinity of the liquid passage space and supplies pressurized air to the sulfur material layer in the first section and the sulfur material layer in the second section.
Have a,
A denitrification treatment apparatus in which the sulfur material for denitrification contains powdered sulfur, an alkaline agent, and a surfactant. A tank that can hold liquids and
In the tank, the first compartment and the second compartment, which are partitioned by the partition wall in the vertical direction and communicated by the liquid passage space directly below the partition wall,
Lower portion of the first compartment, a second at the bottom and the liquid passing space in the compartment, sulfur material layer removal窒用sulfur material is deposited to a height of above the liquid passing space,
With the vibrator installed on the outer surface of the tank and / or in the sulfur material layer,
Have a,
A denitrification treatment apparatus in which the sulfur material for denitrification contains powdered sulfur, an alkaline agent, and a surfactant. The denitrification treatment apparatus according to claim 9 or 10, wherein the alkaline agent contains calcium carbonate and / or magnesium carbonate. The denitrification treatment apparatus according to any one of claims 9 to 11, wherein the alkaline agent contains natural magnesite and / or synthetic magnesite. The denitrification treatment apparatus according to any one of claims 9 to 12, wherein the surfactant contains a nonionic surfactant. The content of the powdered sulfur is 30 to 69.5% by weight, the content of the alkaline agent is 30 to 69.5% by weight, and the surface activity is based on the total weight of the sulfur material for denitrification. The denitrification treatment apparatus according to any one of claims 9 to 13, wherein the content of the agent is 0.5 to 5% by weight. The denitrification according to any one of claims 9 to 14, wherein the alkaline agent contains calcium carbonate, and the content of calcium carbonate particles in a 60 mesh pass is 10% by weight or less based on the total weight of calcium carbonate. Processing equipment. The sulfur material for denitrification according to any one of claims 1 to 5, wherein the alkaline agent has an average particle size of 60 mesh-on and 5 mesh paths.

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