JP6622432B1 - Disinfecting apparatus and disinfecting method for waste water containing ammonia nitrogen - Google Patents

Abstract

Disclosed is a method and an apparatus for disinfecting by adding a disinfectant having excellent handleability to wastewater containing ammonia nitrogen. SOLUTION: Immediately after dissolving a predetermined amount of a solid hypochlorous acid source (B) in a drug (A) containing bromine ions to prepare a disinfectant containing hypochlorous acid, the disinfectant is treated with an ammoniacal disinfectant. Disinfection method to be added to nitrogen-containing wastewater, mixing section 1 for adding and mixing solid hypochlorous acid source (B) to drug (A), receiving mixture from mixing section 1 and converting the mixture to drug (A) Disinfectant preparation unit 2 for dissolving chloric acid source (B) to prepare disinfectant, first line 3 for supplying drug (A) to disinfectant preparation unit 2, disinfectant immediately after preparation from disinfectant preparation unit 2 A disinfecting apparatus comprising a disinfectant supply line 4 for supplying wastewater containing ammoniacal nitrogen to wastewater (hereinafter also referred to as “water to be treated”). [Selection diagram] Fig. 1

Description

  The present invention relates to a disinfecting apparatus and a disinfecting method for ammonia nitrogen-containing wastewater, and particularly to a disinfecting apparatus and disinfecting method for ammonia nitrogen-containing wastewater discharged from a sewage treatment plant, a pump station, and a rainwater outlet to public water areas.

  The sewage treatment plant is a facility for detoxifying sewage discharged from households and factories and releasing it into public water bodies. If inflow sewage significantly exceeds the treatment capacity, such as when there is rainfall exceeding the design value, some sewage during rainy weather will be discharged after simple treatment. Wastewater mixed with rainwater (hereinafter referred to as “rainwater during rainy weather”) is discharged into public water areas without being sufficiently treated. In this case, since coarse suspended solids and SS (suspended substance) are released to public water areas, they may cause aesthetic problems, and the release standard value (3000 CFU / mL) stipulated in the Water Pollution Control Law In some cases, coliforms or E. coli significantly exceeding the following are detected. These are phenomena that are especially seen in combined sewers. However, in shunted sewers, soil coliforms and coarse suspended solids flow in, so if they overflow and are discharged into public waters, they join together. A problem similar to the sewerage system was occurring. Note that Escherichia coli refers only to Esherichia coli, whereas Escherichia coli group includes the genus Citrobacter, Enterobacter, and Klebsiella in addition to Esherichia coli. The coliform group is an index of fecal contamination, and is an inspection item for confirming safety against intestinal pathogens (such as Salmonella typhi and Shigella).

Disinfection at sewage treatment plants includes “Sewerage facility planning / design guidelines and explanation” (published by Japan Sewerage Association, 2009 edition), such as sodium hypochlorite, liquefied chlorine, chlorinated isocyanuric acid, calcium hypochlorite, etc. A method of disinfecting coliform bacteria by contacting them with sewage in a mixing pond for 15 minutes or longer is shown. Chlorine disinfectants generate hypochlorous acid as a free base in sewage, destroy cell membranes and cell walls of pathogenic substances such as microorganisms and viruses with strong oxidizing power, and denature intracellular proteins and nucleic acids. In addition, “Sewerage facility planning / design guidelines and explanation” also describes disinfection with ozone and ultraviolet rays. In addition, a pond of tens of thousands of m ³ is provided to temporarily store sewage in rainy weather, and when overflow occurs due to rainfall exceeding the storage amount, a method of disinfecting using the above-mentioned chlorinated disinfectant is also available. Proposed. In recent years, a technique using a bromine-based disinfectant in addition to a chlorine-based disinfectant has been proposed.

  For example, a disinfectant for drainage characterized by containing hypobromite or hypobromite formed by mixing a bromide of a metal element and hypochlorous acid or a salt thereof (Patent Literature) 1), (A) a compound that generates hypochlorous acid in water and (B) a compound that generates bromide ions in water. (C) in the presence of hydroxycarboxylic acid and / or oxocarboxylic acid, the pH is 5 to 5. 7. Disinfectant characterized by containing hypobromite obtained by mixing in an aqueous system (Patent Document 2), (a) hydrobromic acid, bromide that releases bromide ions when dissolved in water A bromide selected from sodium, potassium bromide, lithium bromide and zinc bromide, (b) 5,5-dialkyl-substituted hydantoin, and (c) hypochlorous acid and / or a water-soluble salt thereof are treated. (C) :( a) (B) = 1: (0.2-3): (0.2-0.9) is added and mixed in a molar ratio, and in the aqueous system, (A) hypobromite and / or a water-soluble salt thereof (B) A slime control method in an aqueous system characterized by producing an N-monochloro-5,5-dialkyl-substituted hydantoin (Patent Document 3), a bromine-based oxidizing agent in water, or a bromine-based compound and a chlorine-based oxidizing agent; A method of disinfecting water (Patent Document 4) and the like in which a stabilized hypobromite composition containing a reaction product of the above and a sulfamic acid compound and a chlorine-based oxidizing agent are added has been proposed.

In the method of Patent Document 1, when the drug is liquid, decomposition proceeds with time, and retention of active ingredients and storage stability of the disinfectant are insufficient as a disinfectant for sewage in rainy weather. If the agent is a solid powder or the like, such as a corrosive dust is difficult to handle than the liquid, quantitative injection is difficult, practical application is difficult. Patent Document 1 does not describe the mixing ratio of metal bromide and hypochlorous acid or a salt thereof that maximizes the disinfection effect.

  In the method of Patent Document 2, when (C) a component such as hydroxycarboxylic acid and / or oxocarboxylic acid is used, the treatment with three agents becomes complicated and the manufacture of the drug becomes complicated, and the organic component derived from component (C) is not covered. There is a demerit such that COD value is increased by adding to treated water.

  The method of Patent Document 3 uses an expensive alkyl-substituted hydantoin, and thus has a problem that the disinfection cost becomes high.

  In the method of Patent Document 4, the use of sulfamic acid complicates the drug composition, which not only complicates the production, but also increases the raw material cost. Furthermore, the addition of sulfamic acid has the disadvantage that the concentration of the active ingredient acting as a disinfecting component is reduced. Moreover, when preparing a disinfectant on site, there are disadvantages such as an increase in the number of reactors and injection devices, leading to an increase in installation costs and difficulty in injection control.

JP 2003-012425 A JP 2004-244372 A JP 2009-226409 A JP 2016-209837 A

  Conventionally, when a liquid with good handleability is used, a stabilizer is essential because hypochlorous acid and hypobromite are rich in reaction activity and deteriorate in a short time. In addition, when powder is used as a hypobromite compound or hypochlorous acid compound, unlike the case of liquids, it is known that the chemicals are less likely to deteriorate over time, but dust is generated due to the use of fine particles. Therefore, injection control is difficult and practical application is difficult. In particular, oxidizing powders such as hypochlorous acid compounds have a high risk when workers come into contact with dust and are very difficult to handle.

  An object of the present invention is to provide a method and an apparatus for disinfecting a conventional disinfecting method by eliminating the disadvantages of the conventional disinfecting method and adding a disinfectant excellent in handleability to ammonia nitrogen-containing waste water.

Means to solve the problem

ADVANTAGE OF THE INVENTION According to this invention, the disinfectant excellent in the handleability and long-term storage property is added to the ammonia-containing nitrogen-containing waste water, and the method and apparatus disinfected are provided. Specific embodiments of the present invention are as follows.
[1] A predetermined amount of solid hypochlorous acid source (B) is supplied to the drug (A) containing bromine ions, and the solid hypochlorous acid source (B) is dissolved in the drug (A). A device for preparing a disinfectant containing hypochlorous acid and adding a disinfectant to the ammoniacal nitrogen-containing wastewater.
[2] The ammonia nitrogen-containing waste water disinfection device according to [1], wherein the means for preparing the disinfectant and adding it to the ammonia nitrogen-containing waste water includes an ejector or a line mixer.
[3] The means for preparing the disinfectant and adding it to the ammoniacal nitrogen-containing wastewater includes a large-diameter portion for receiving the solid hypochlorous acid source (B), and a small-diameter portion connected to the inlet of the ejector or line mixer. The disinfecting apparatus for wastewater containing ammonia nitrogen according to [2], further comprising a conical container having
[4] Ammonia according to any one of [1] to [3], further comprising means for supplying a predetermined amount of bromine compound to a solvent to prepare the drug (A) containing bromine ions. Disinfection equipment for nitrogen-containing wastewater.
[5] The method according to [4], further including means for preparing the chemical (A) using the ammonia nitrogen-containing waste water to be treated as the solvent, and taking in the ammonia nitrogen-containing waste water to be treated. Disinfection device for ammonia-containing wastewater as described.
[6] A first sensor for measuring water quality of ammoniacal nitrogen-containing waste water before adding the disinfectant;
A second sensor for measuring the quality of the ammoniacal nitrogen-containing wastewater after adding the disinfectant;
An operator electrically connected to the first sensor and the second sensor, and based on a signal from the operator, the drug (A) and the solid hypochlorous acid source (B) The ammonia nitrogen-containing wastewater disinfection device according to any one of the above [1] to [5], comprising a control means for controlling the mixing ratio.
[7] Supply a predetermined amount of solid hypochlorous acid source (B) to the bromine ion-containing drug (A), dissolve it, prepare a disinfectant containing hypochlorous acid, and contain ammonia nitrogen A method for disinfecting wastewater containing ammonia nitrogen, including a step of adding to wastewater.
[8] The disinfectant is added to the ammoniacal nitrogen-containing wastewater within a range of 1 second to less than 300 seconds after the solid hypochlorous acid source (B) is added to the drug (A). [7] Disinfection method of waste water containing ammonia nitrogen described in 1.
[9] The bromine compound is at least one selected from sodium bromide, potassium bromide, ammonium bromide, calcium bromide, and dibromoisocyanuric acid,
The solid hypochlorous acid source (B) is at least one selected from hypochlorite, dichloroisocyanuric acid or a salt thereof, trichloroisocyanuric acid or a salt thereof, and is ammoniac as described in [7]. Disinfection method for nitrogen-containing wastewater.
[10] Ammonia nitrogen according to any one of [7] to [9], further including a step of supplying a predetermined amount of bromine compound to a solvent to prepare the drug (A) containing bromine ions. Disinfection method of wastewater contained.
[11] The method for disinfecting ammonia-containing nitrogen-containing waste water according to [10], wherein the ammonia-containing nitrogen-containing waste water to be treated is used as the solvent.
[12] Measure the water quality of the ammonia nitrogen-containing waste water before adding the disinfectant,
Measure the water quality of ammonia nitrogen containing waste water after adding the disinfectant,
The method further includes the step of controlling a mixing ratio of the bromine compound and the solid hypochlorous acid source (B) based on a difference in water quality of the ammoniacal nitrogen-containing wastewater before and after adding the disinfectant. ] The disinfection method of the ammonia nitrogen containing waste water of any one of [11].

  Since the disinfection method and apparatus of the present invention can prepare and add a disinfectant at the disinfecting site of ammonia-containing nitrogen-containing wastewater, facilitating the handling of a hypochlorous acid source that is a dangerous substance, Before the decomposition of the active ingredient, the ammoniacal nitrogen-containing waste water can be disinfected.

It is explanatory drawing which shows the outline | summary of 1st Embodiment of the disinfection apparatus of the ammonia nitrogen containing waste_water | drain of this invention. It is explanatory drawing which shows the outline | summary of 2nd Embodiment of the disinfection apparatus of the ammonia nitrogen containing waste_water | drain of this invention. It is explanatory drawing which shows the outline | summary of 3rd Embodiment of the disinfection apparatus of the ammonia nitrogen containing waste_water | drain of this invention. It is explanatory drawing which shows the outline | summary of 4th Embodiment of the disinfection apparatus of the ammonia nitrogen containing waste_water | drain of this invention. It is a schematic explanatory drawing which shows an example of the apparatus which supplies quantitatively the solid hypochlorous acid source (B) used with the disinfection apparatus of FIGS. 1-4.

Preferred embodiment

  Hereinafter, the present invention will be described in detail with reference to the accompanying drawings, but the present invention is not limited thereto.

In FIG. 1, the outline | summary of 1st Embodiment of the disinfection apparatus of the ammonia nitrogen containing waste_water | drain of this invention is shown. The ammonia nitrogen-containing waste water disinfection device of the present invention prepares a disinfectant containing hypochlorous acid by dissolving a predetermined amount of a solid hypochlorous acid source (B) in a medicine (A) containing bromine ions. immediately after, including means to add the disinfectant to ammonium nitrogen-containing waste water. Is a means to add the disinfectant to ammonium nitrogen-containing waste water, solid hypochlorite sources in drug (A) containing bromine ion (B) 300 seconds or more and less than 1 second after the addition of, preferably Preferably has a configuration in which the disinfectant can be added to the ammoniacal nitrogen-containing waste water within a time period of 1 second to 60 seconds, and an ejector or a line capable of dissolving the drug and ejecting the disinfectant in a very short time It is preferable to include a mixer.

Means to add the disinfectant to ammonium nitrogen-containing waste water, the agent (A) a solid hypochlorite source (B) mixing section 1 for mixing with the addition of, accepts mixture from the mixing unit 1 drugs ( Dissolving hypochlorous acid source (B) in A) to prepare a disinfectant, disinfectant preparation unit 2, first line 3 for supplying agent (A) to disinfectant preparation unit 2, disinfectant preparation unit 2 A disinfectant supply line 4 for supplying the disinfectant immediately after preparation to the ammoniacal nitrogen-containing waste water (hereinafter also referred to as “treated water”) is provided.

  As the disinfectant preparation unit 2, an ejector or a line mixer can be preferably exemplified. An ejector is a device that draws in and discharges a low-pressure fluid using the force of a high-pressure fluid, and sucks a powdery hypochlorous acid source (B) into the ejector and flows into the ejector (A ) Can be efficiently dissolved in a short time and the prepared disinfectant can be sprayed into the water to be treated. The line mixer is a high-pressure stirring device installed in the pipe. The powdered hypochlorous acid source (B) is charged into the chemical (A) in the line mixer and stirred under high pressure. It can be transferred quickly. By using an ejector or a line mixer, the dissolution of the solid hypochlorous acid source (B) in the drug (A) is promoted, and the preparation from the disinfectant to the addition to the ammonia nitrogen-containing wastewater is performed in a short time. Therefore, the active ingredient of the disinfectant works well without being attenuated. In addition, since it is possible to prevent clogging due to accumulation of undissolved solids in the piping, stable and continuous operation is possible.

  As the mixing unit 1, it is preferable to use a conical container having a large-diameter part 1 a that receives a solid hypochlorous acid source (B) and a small-diameter part 1 b that is connected to the inlet 2 a of the disinfectant preparation part 2. it can. The first line 3 is preferably connected tangentially to the upper part 1a of the side wall of the conical container so that the drug (A) can be supplied as a vortex along the tapered inner surface of the conical container.

  In FIG. 2, the outline | summary of 2nd Embodiment of the disinfection apparatus of this invention is shown. The second embodiment has the same configuration as the first embodiment, except that it further comprises means for preparing the drug (A). The same constituent elements as those in the first embodiment shown in FIG.

In the second embodiment, as a means to prepare a medicament (A), the bromine compound reservoir 5 for storing the bromine compound, a liquid storage tank 6 for storing liquid to be dissolved or diluted bromine compound, a bromine compound storage tank 5 The second line 7 for supplying a bromine compound from the liquid tank 6 and the third line 8 for supplying a liquid from the liquid storage tank 6 and receiving the bromine compound are provided. The third line 8 is connected to the disinfectant preparation unit 2. The first line 3 is connected to the third line 8 on the upstream side of the connection portion between the third line 8 and the disinfectant preparation unit 2.

  In the second embodiment, the bromine compound stored in the bromine compound storage tank 5 may be a solid bromine compound or a liquid containing bromine ions. The liquid stored in the liquid storage tank 6 is not particularly limited as long as it can dissolve a solid bromine compound or dilute a liquid containing bromine ions. Tap water, well water, industrial water, rainwater, sewage , Primary treated water from sewage treatment plant, sewage after biological treatment, discharged water after advanced treatment, simplified treated water, sedimentation treated water, treated water from human waste treatment plant, containing ammoniacal nitrogen which is treated in the present invention It can be any liquid such as drainage.

  In FIG. 3, the outline | summary of 3rd Embodiment of the disinfection apparatus of this invention is shown. The third embodiment has the same configuration as that of the first embodiment except that it further includes a control means for controlling the mixing ratio of the drug (A) and the solid hypochlorous acid source (B). The same constituent elements as those in the first embodiment shown in FIG.

Control Hand stage in the third embodiment measures the ammonia nitrogen containing waste water quality after addition of the first sensor 111, disinfectants for measuring the ammonium nitrogen-containing wastewater quality prior to the addition of disinfectant Second sensor 112, first sensor 111, operator 113 electrically connected to second sensor 112, and drug (A) and solid hypochlorous acid based on a signal from operator 113 Control means 114 and 115 for controlling the mixing ratio with the source (B) are provided.

  As the first sensor 111, a sensor that can measure turbidity, ammoniacal nitrogen concentration, electrical conductivity, and the like can be preferably used. As the second sensor 112, a sensor that can measure a residual halogen concentration, an ammoniacal nitrogen concentration, electrical conductivity, and the like can be preferably used.

  The operator 113 considers not only the water quality information from the first sensor 111 and the second sensor 112 but also information such as the rainfall amount, the rainfall time, and the rainwater pump operation time, and controls the control means 114 and 115 with a control signal. May be sent.

  The control means 114 is not particularly limited as long as it is electrically connected to the operator 113 and can control the supply of the medicine (A). For example, the control means 114 is provided in the first line 3 for supplying the medicine (A). A control valve, a pump, or the like can be used. The control means 115 is not particularly limited as long as it is electrically connected to the operator 113 and can control the supply of the solid hypochlorous acid source (B), for example, the solid hypochlorous acid source (B ) Can be used.

  In FIG. 4, the outline | summary of 4th Embodiment of the disinfection apparatus of this invention is shown. The fourth embodiment has the same configuration as that of the second embodiment except that it further includes a control means for controlling the mixing ratio of the drug (A) and the solid hypochlorous acid source (B). The same components as those in the second embodiment shown in FIG. 2 are denoted by the same reference numerals and description thereof is omitted, and the same components of the control means shown in FIG. 3 are denoted by the same reference numerals and description thereof is omitted.

  In the fourth embodiment, the control means 114 is a control valve or pump for controlling supply of bromine compound from the bromine compound storage tank 5 and / or supply of liquid from the liquid storage tank 6, or the first line 3, second line. A control valve, a pump, or the like provided in one or more of 7 and the third line 8 can be used.

  In the disinfection apparatus shown in FIGS. 1 to 4, the apparatus for quantitatively supplying the solid hypochlorous acid source (B) to the drug (A) is not particularly limited, and a normal powder quantitative supply apparatus can be used. It is preferable that the powder fixed quantity supply device can prevent the solidification due to the compaction of the powder and can supply a necessary amount of the powder when necessary without touching the powder. For example, a powder flow tank 11 for storing powder while supplying compressed air from the bottom of the tank shown in FIG. 5 to maintain a powder fluidized bed, and a powder provided in the lower stage of the powder flow tank 11 A powder quantitative supply device including the body quantitative supply chamber 12 can be preferably used.

  As an example, a powder flow tank 11 shown in FIG. 5 has a compressed air inlet 13 at the bottom. In order to prevent the powder from getting wet or solidified inside the tank, compressed air is periodically blown to make the powder flow. A rotating blade 14 is provided in the lower part of the powder flow tank 11. An opening 14 a is provided at the outer peripheral end of the rotary blade 14, and a predetermined amount of powder is dropped into the powder quantitative supply chamber 12. The powder quantification supply chamber 12 has a powder outlet 12a on the bottom surface, and supplies the quantified powder to the mixing unit 1 for disinfectant preparation shown in FIGS. A rotary table 15 is provided in the lower part of the powder fixed amount supply chamber 12. On the outer periphery of the rotary table, a plurality of measuring chambers 15a whose upper and bottom surfaces are opened are provided at predetermined intervals. On the upper surface of the turntable 15, a scraping plate (not shown) for measuring a predetermined amount in contact with the upper surface of the measuring chamber 15 a is provided. When the rotary table 15 rotates while being in contact with the fixed grinding plate and the measuring chamber 15a reaches the position of the powder outlet 12a, a predetermined amount of powder dropped into the measuring chamber 15a is mixed from the powder outlet 12a. Supplied to section 1.

Next, the method for disinfecting ammonia nitrogen-containing waste water of the present invention will be described.
The method for disinfecting ammonia-containing nitrogen-containing waste water according to the present invention supplies a predetermined amount of a solid hypochlorous acid source (B) to a bromine ion-containing chemical (A) and dissolves it, thereby disinfecting the hypochlorous acid. And adding the prepared disinfectant to the ammoniacal nitrogen-containing wastewater.

  The agent (A) containing bromine ions may be an aqueous solution containing bromine ions prepared in advance or a liquid containing bromine ions prepared by dissolving bromine compounds in situ. The bromine compound is preferably at least one selected from sodium bromide, potassium bromide, ammonium bromide, calcium bromide, and dibromoisocyanuric acid. Liquids that dissolve bromine compounds or dilute bromine ion aqueous solutions include tap water, well water, industrial water, rainwater, sewage, primary treated water from sewage treatment plants, sewage after biological treatment, and discharged water after advanced treatment. Any liquid such as simple treated water, sedimentation treated water, treated water from a human waste treatment plant, or ammoniacal nitrogen-containing wastewater to be treated in the present invention can be preferably used.

  The solid hypochlorous acid source (B) is preferably at least one selected from hypochlorite, dichloroisocyanuric acid or a salt thereof, trichloroisocyanuric acid or a salt thereof. Preferred examples of hypochlorite include sodium hypochlorite and calcium hypochlorite, and powders such as bleached powder or highly bleached powder can be used. Preferable examples of the salt of dichloroisocyanuric acid include powders or granules of sodium dichloroisocyanurate, sodium dichloroisocyanurate dihydrate, potassium dichloroisocyanurate, ammonium dichloroisocyanurate. Preferred examples of the trichloroisocyanurate include powders or granules such as sodium trichloroisocyanurate and potassium trichloroisocyanurate.

  The time until the disinfectant is prepared and added to the ammoniacal nitrogen-containing wastewater is in the range of 1 second to less than 300 seconds from the addition of the solid hypochlorous acid source (B) to the drug (A), preferably The range of 1 second to 60 seconds is desirable. If it is less than 1 second, the disinfection effect is insufficient, and if it exceeds 300 seconds, the reaction of the drug is terminated, and the disinfection effect may be attenuated.

The method for disinfecting ammonia nitrogen-containing wastewater according to the present invention measures the quality of ammonia nitrogen-containing wastewater before adding the disinfectant, measures the quality of ammonia nitrogen-containing wastewater after adding the disinfectant, and disinfects The method further includes a step of controlling the mixing ratio of the chemical containing bromide (A) and the solid hypochlorous acid source (B) based on the difference in water quality of the ammonia nitrogen-containing wastewater before and after the addition of the medicine. Is preferred. The water quality that can be used as an index for controlling the mixing ratio of the bromine ion-containing drug (A) and the solid hypochlorous acid source (B) is preferably ammonium ion concentration, turbidity, conductivity, etc. Can be mentioned. The ammonium ion concentration can be measured using a commercially available densitometer such as an ion electrode type continuous measurement device (AISE _SC manufactured by HACH). In addition, based on the results of analyzing the quality of sewage in the past in the rain, the ammonium ion concentration can be estimated from the operating conditions such as the elapsed time from the start of discharge and the amount of discharged water.

Using the residual free halogen concentration as an index, the disinfectant effects of the disinfectant due to the difference in the state of each drug and the order of addition to pure water were compared.
(Disinfectant 1) One second after adding 11.2 ml of 40% potassium bromide aqueous solution to 1 L of pure water, 2.7 g of sodium dichloroisocyanurate granules were added to prepare a disinfectant. The residual free halogen concentration was measured after 2 seconds and after 90 seconds.
(Disinfectant 2) One second after adding 2.7 g of sodium dichloroisocyanurate granules to 1 L of pure water, 11.2 ml of 40% potassium bromide aqueous solution was added to prepare a disinfectant, and after 30 seconds and 90 seconds Later, the residual free halogen concentration was measured.
(Disinfectant 3) Prepare a disinfectant by mixing 4.48 g of potassium bromide solid and 2.7 g of sodium dichloroisocyanurate granules, add this disinfectant to 1 L of pure water, 30 seconds later and After 90 seconds, the residual free halogen concentration was measured.
(Disinfectant 4) A disinfectant was prepared by mixing 11.2 ml of 40% aqueous potassium bromide solution and 2.7 g of sodium dichloroisocyanurate granules. This disinfectant was added to 1 L of pure water, and remained after 60 seconds. The free halogen concentration was measured.

In disinfectants 1 to 4, the molar ratio of potassium bromide to sodium dichloroisocyanurate was 1: 1.5, and the disinfectant injection rate was 8 mg / L as Cl _{2 in} terms of effective chlorine concentration. During the addition, stirring was always performed at 600 rpm / min. The residual free halogen value was measured by collecting water from the middle layer of each solution using a micropipette. The results are shown in Table 1.

  In the disinfectants 1 to 3, the residual free halogen concentration after 90 seconds is almost the same, and it is considered that there is no significant difference in the disinfecting effect. However, in the disinfectant 4 in which solid sodium dichloroisocyanurate and liquid potassium bromide are mixed in advance, the concentration is less than half that of Example 1 after 60 seconds, and the disinfecting effect is considered to be drastically reduced. .

  Next, 7.49 g of ammonium chloride (2520 mg / L as NH 4) was added to the pure water as the liquid to be treated, and after confirming that it was completely dissolved, the chemical was added immediately, 30 seconds later and 60 seconds The results of measuring the residual free halogen concentration after 1 second are shown in Table 2.

In Example 1, 11.2 mL of 40% potassium bromide aqueous solution was first added to the treatment liquid, and then 2.7 g of sodium dichloroisocyanurate granules were added to the treatment liquid.
In Comparative Example 1, 2.7 g of sodium dichloroisocyanurate granules were first added to the liquid to be treated, and then 11.2 mL of 40% potassium bromide aqueous solution was added to the liquid to be treated.

In both Example 1 and Comparative Example 1, the molar ratio of potassium bromide and sodium dichloroisocyanurate was 1: 1.5, and the disinfectant injection rate was 8 mg / L as Cl _{2 in} terms of effective chlorine concentration. Stirring was always performed at 600 rpm / min when each drug was added. The residual halogen concentration was measured by collecting water from the middle layer of each solution using a micropipette.

  In Example 1, the residual free halogen concentration was high both after 30 seconds and after 60 seconds, and the disinfection effect was maintained. In Comparative Example 1, the disinfection effect was drastically reduced to 180 mg / L after 60 seconds, and the disinfection effect was maintained. It is thought that it is not done. The chemical addition sequence to pure water did not show a significant difference in residual free halogen concentration as an indicator of the disinfection effect, but it was confirmed that the chemical addition sequence to ammonium-containing water caused a significant difference in maintaining the disinfection effect. It was.

  Further, ammonium chloride and a bacterial solution containing coliforms were added to 1 L of pure water to prepare simulated ammonium ion-containing wastewater, and the effect of the drug addition sequence was confirmed.

  In Example 2, 1.0 g of solid potassium bromide was added to 100 mL of simulated ammonium ion-containing wastewater to prepare a simulated wastewater containing 1% potassium bromide, and then 8.54 mg of sodium dichloroisocyanurate granules were treated with 1% odor. The drug prepared by adding 0.92 mL of potassium fluoride-containing simulated waste water was added to 1 L of simulated waste water containing simulated ammonium ions and Escherichia coli.

  In Comparative Example 2, 8.54 mg of sodium dichloroisocyanurate granules were added to 0.92 mL of simulated ammonium ion-containing wastewater, and then 9.2 mg of solid potassium bromide was added to 0.92 mL of simulated ammonium ion-containing wastewater. The drug thus prepared was added to 1 L of simulated waste water containing simulated ammonium ions and E. coli.

In both Example 2 and Comparative Example 2, the molar ratio of potassium bromide and sodium dichloroisocyanurate was 1: 1, and the disinfectant injection rate was 8 mg / L in terms of effective chlorine concentration. Stirring was always performed at 150 rpm / min. The residual halogen value was measured by collecting water from the middle layer of each solution using a micropipette 60 seconds after the addition of the drug. The number of coliforms was measured by the method described in Appendix 1 of the Ministerial Ordinance (December 17, 1963, Ministry of Health and Construction Ordinance No. 1) on the method of testing the quality of sewage water. The results are shown in Table 3.

  In Example 2, the residual free halogen concentration 60 seconds after addition of the disinfectant was 2.9 mg / L, and the coliform group was not detected. In Comparative Example 2, the residual free halogen concentration 60 seconds after addition of the disinfectant was 1.6 mg / L, and the coliform group was detected at 630 cfu / ml. In both Example 2 and Comparative Example 2, the number of coliforms satisfies the release standard value, but the disinfection effect of Example 2 in which the potassium bromide solution is added first and then the granules of sodium dichloroisocyanurate are added. It can be confirmed that it is superior. The present invention is particularly useful for simple disinfection of rainy sewage that is discharged into public waters without being sufficiently treated.

Claims (10)

A predetermined amount of solid hypochlorous acid source (B) is supplied to the drug (A) containing bromine ions, and the solid hypochlorous acid source (B) is dissolved in the drug (A). A means for preparing a disinfectant containing chlorous acid and adding the disinfectant to the ammoniacal nitrogen-containing waste water is provided .
The means for preparing the disinfectant and adding it to the ammoniacal nitrogen-containing wastewater includes an ejector or a line mixer, and is connected to a large-diameter portion for receiving a solid hypochlorous acid source (B) and an inlet of the ejector or the line mixer. A conical container having a small diameter portion,
Disinfection equipment for wastewater containing ammonia nitrogen.   The disinfecting apparatus for ammonia nitrogen-containing wastewater according to claim 1, further comprising means for supplying a predetermined amount of bromine compound to a solvent to prepare the medicine (A) containing bromine ions. The ammoniacal gas according to claim 2 , further comprising means for taking up ammonia nitrogen-containing wastewater to be treated into means for preparing the chemical (A) using ammonia nitrogen-containing wastewater to be treated as the solvent. Disinfection equipment for nitrogen-containing wastewater. A first sensor for measuring water quality of ammoniacal nitrogen-containing wastewater before adding the disinfectant;
A second sensor for measuring the quality of the ammoniacal nitrogen-containing wastewater after adding the disinfectant;
An operator electrically connected to the first sensor and the second sensor, and based on a signal from the operator, the drug (A) and the solid hypochlorous acid source (B) The disinfecting apparatus for ammonia-containing nitrogen-containing wastewater according to any one of claims 1 to 3 , further comprising a control means for controlling the mixing ratio. A predetermined amount of solid hypochlorous acid source (B) is supplied to the drug (A) containing bromine ions, and the solid hypochlorous acid source (B) is dissolved in the drug (A). Means for preparing a disinfectant containing chlorous acid and adding the disinfectant to the ammoniacal nitrogen-containing waste water;
A first sensor for measuring water quality of ammoniacal nitrogen-containing wastewater before adding the disinfectant;
A second sensor for measuring the quality of the ammoniacal nitrogen-containing wastewater after adding the disinfectant;
An operator electrically connected to the first sensor and the second sensor, and based on a signal from the operator, the drug (A) and the solid hypochlorous acid source (B) A disinfecting apparatus for wastewater containing ammonia nitrogen, comprising a control means for controlling the mixing ratio. A prescribed amount of solid hypochlorous acid source (B) is supplied to a chemical containing bromide (A) and dissolved to prepare a disinfectant containing hypochlorous acid and added to wastewater containing ammoniacal nitrogen. And a process of
Measure the water quality of ammonia nitrogen containing waste water before adding the disinfectant,
Measure the water quality of ammonia nitrogen containing waste water after adding the disinfectant,
A step of controlling the mixing ratio of the bromine compound and the solid hypochlorous acid source (B) based on the difference in water quality of the ammoniacal nitrogen-containing wastewater before and after adding the disinfectant;
Disinfection method for wastewater containing ammonia nitrogen. The ammonia according to claim 6 , wherein the disinfectant is added to the ammoniacal nitrogen-containing waste water within a range of 1 second to less than 300 seconds after the solid hypochlorous acid source (B) is added to the drug (A). To disinfect wastewater containing nitrogen. The bromine compound is at least one selected from sodium bromide, potassium bromide, ammonium bromide, calcium bromide, and dibromoisocyanuric acid,
The ammonia according to claim 6 or 7 , wherein the solid hypochlorous acid source (B) is at least one selected from hypochlorite, dichloroisocyanuric acid or a salt thereof, trichloroisocyanuric acid or a salt thereof. To disinfect wastewater containing nitrogen. The method for disinfecting ammonia-containing nitrogen-containing wastewater according to any one of claims 6 to 8 , further comprising a step of supplying a predetermined amount of bromine compound to a solvent to prepare the agent (A) containing bromine ions. The method for disinfecting ammonia-containing nitrogen-containing wastewater according to claim 9 , wherein ammonia-containing nitrogen-containing wastewater to be treated is used as the solvent.

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