JP4175037B2 - Organic wastewater treatment equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention mainly relates to a pretreatment facility for biological treatment of organic wastewater, and more particularly, organic wastewater containing hardly decomposable organic components, particularly difficult decomposition of alcohols and acetates contained in wastewater. The present invention relates to an organic wastewater treatment apparatus newly provided between an aeration tank, which performs a biological treatment on a tower-type ozone contact tank, which purifies an organic organic component.
[0002]
[Prior art]
Conventionally, domestic wastewater such as canteens and toilets among office wastewater is organic wastewater containing soluble organic substances mainly composed of polysaccharides, so it is relatively easy to use biological treatment, that is, the conventional activated sludge method using microorganism enzymes. Easy purification process.
[0003]
The biological treatment is also roughly classified into aerobic microorganism treatment, anaerobic microorganism treatment, and specific microorganism treatment depending on the type of microorganism.
[0004]
Furthermore, the aerobic microorganism treatment is also carried out by a floating treatment method and a non-floating treatment depending on whether the treatment is performed in a state where the microorganisms are suspended in water, or in a state where the microorganism is fixed on the surface of the support or inside the support. Divided into methods (biofilm treatment methods).
[0005]
A typical method using the aerobic microorganisms in a floating state is a biological treatment method called a so-called “activated sludge method”.
[0006]
The microorganism is a bacterium having a size of about 0.5 μm to 1.0 μm. In actual biological treatment, it is often symbiotic with protozoa, etc., which are one level biologically high.
[0007]
For example, as shown in FIG. 5, a conventional activated sludge process apparatus has an organic drainage inflow pipe 8 having an organic drainage inlet 6 connected to the inflow side of the flow rate adjustment tank 1, and the flow rate adjustment tank. 1 and the aeration tank 3 are connected via a connection pipe 9, the aeration tank 3 and the aeration tank 4 are connected via a connection pipe 13, and the aeration tank 4 and the precipitation separation tank 5 are connected to each other. Connected via a connecting pipe 14 and provided with a purified water discharge pipe 16 having a purified water discharge port 7 on the discharge side of the sedimentation separation tank 5, and further for recycling sludge, the bottom of the aeration tank 3 This is an organic wastewater treatment apparatus B in which the bottom of the sedimentation separation tank 5 is connected via a sludge return pipe 15 and a sludge return pump 21 is provided at an arbitrary position of the sludge return pipe 15.
[0008]
This activated sludge method is the most popular treatment method among biological treatments. As a component of the activated sludge method, a process that satisfies the three conditions of “aeration tank”, “precipitation separation tank”, and “sludge return bypass” is the point of purification treatment.
[0009]
In the conventional purification treatment of organic wastewater, the drainage process has been devised in advance so as to dilute with dilution water or the like to a concentration suitable for biological treatment, to equalize the treatment load, and to maintain a constant treatment efficiency.
[0010]
That is, the flow rate adjustment tank that makes the flow rate uniform in advance so that the amount of waste water does not change greatly at time intervals and the sudden and high concentration waste water does not flow into the biological treatment process consisting of an aeration tank that is a direct purification process. Is provided.
[0011]
The flow rate adjusting tank may be provided with a plurality of the flow rate adjusting tanks in series according to the inflow amount of organic waste water or the concentration of organic components in the organic waste water.
[0012]
Next, the organic waste water in which the inflow amount and the organic component concentration in the organic waste water are adjusted in the flow rate adjusting tank flows into the aeration tank which is a biological treatment process. The aeration tank is the most important process in the conventional activated sludge process.
[0013]
An aerobic microorganism group is present in the aeration tank, and the organic component in the organic wastewater and the aerobic microorganism are mixed and contacted to oxidize and decompose the organic component in the organic wastewater in the presence of dissolved oxygen.
[0014]
The aerobic microorganism group is a microorganism that cannot act without air, that is, oxygen. This aerobic microorganism group is not only a single microorganism but also a mixture of many types of bacteria and protozoa.
[0015]
The action of the aerobic microorganism group is to first adsorb the soluble organic component in the wastewater in a short time, oxidatively decompose the soluble organic component by the microbial enzyme while consuming dissolved oxygen in the wastewater, and finally Breaks down into carbon dioxide and water.
[0016]
It is important that the supply of oxygen necessary for the oxidative decomposition action in which the aerobic microorganism group existing in the aeration tank oxidizes organic components is sent to the aeration tank as small bubbles. Small bubbles increase the contact area with water and increase the dissolution efficiency of oxygen in water.
[0017]
As an apparatus for sending air into the aeration tank, an air diffuser made of a plate-like air diffuser plate or a cylindrical air diffuser made of a material such as ceramic or synthetic resin is used.
[0018]
The air diffuser is installed at the bottom or lower part in the aeration tank, and air is fed by a blower. Small bubbles blowing up from the air diffuser give a swirling flow to the waste water in the aeration tank, the whole waste water is stirred, and oxygen is sufficiently supplied to the waste water.
[0019]
The aeration apparatus is provided with an aerobic microorganism group present in the aeration tank that supplies oxygen necessary for oxidative decomposition of organic components in the organic wastewater and oxygen supplied by the aerobic microorganism group into the wastewater. It also serves the role of stirring the waste water so that it can be taken in.
[0020]
The oxygen dissolution efficiency between the oxygen fed by the air diffuser and the oxygen dissolved in the waste water is usually about 5% to 15%. In addition to the above-described small bubble diffuser, there are a “surface mechanical aeration method” or a “pure oxygen aeration method” using pure oxygen instead of air.
[0021]
The number of aeration tanks may be one or a plurality of aeration tanks depending on the inflow amount of organic waste water and the concentration of organic components in the organic waste water.
[0022]
The mixed solution of the aerobic microorganism group and the organic waste water discharged from the last aeration tank flows into the next precipitation separation tank as it is. In the sedimentation separation tank, the mixed solution is not stirred and is in a stationary state, so that the aerobic microorganism group aggregates and settles in a large lump, and only the purified supernatant is discharged as purified water.
[0023]
The aerobic microorganism group (activated sludge) sedimented and concentrated in the sedimentation separation tank is returned to the first aeration tank by a sludge return pump through a sludge return pipe.
[0024]
The returned sludge is used again for the oxidative decomposition of the organic components in the organic waste water. However, if the amount grown in this process is not removed outside the system, the whole balance cannot be achieved. If the sludge in the aeration tank becomes too thick, the supply of oxygen may not be able to keep up.
[0025]
The organic wastewater treatment equipment in the conventional activated sludge method is used in the case where a plurality of aeration tanks are provided in series according to the inflow amount of organic wastewater or the concentration of organic components in the organic wastewater, etc. In some cases, a plurality of waste water treatment apparatuses provided in parallel are provided in parallel.
[0026]
The organic wastewater treatment apparatus in the conventional activated sludge method as described above is suitable for purification treatment of organic wastewater mainly composed of polysaccharides such as domestic wastewater.
[0027]
However, from various production processes that produce industrial products such as painting processes that paint plastic materials with color materials and printing processes that apply design patterns, etc., difficult-degradable organic components such as color materials and organic solvents are used. Organic drainage containing is common.
[0028]
In addition, wastewater discharged after cleaning of semiconductor-related precision equipment is organic wastewater containing persistent organic components such as organic solvents.
[0029]
Furthermore, there are many organic wastewaters containing hardly decomposable organic components such as colorants in the fiber manufacturing process and dyeing process of the fiber manufacturing and processing industry.
[0030]
These hardly decomposable organic components generally have a large molecular structure or a strong intermolecular bond, and it is difficult to completely purify them with an organic wastewater treatment apparatus in the conventional activated sludge process.
[0031]
In addition, it is indispensable to install purification treatment equipment such as a large tank for the amount of waste water, and there is a problem that the installation cost of the equipment, the installation location and the operation cost are increased.
[0032]
Therefore, a tower-type ozone contact tank is newly installed between the flow rate adjustment tank of the organic waste water treatment apparatus in the conventional activated sludge process and the first tank, and chemical treatment is added in advance, so that Refractory organic components can also be completely purified, and the large-scale aeration tank equipment in the conventional activated sludge method becomes compact, reducing installation costs, installation location, and operating costs, and purifying them as a whole. The present invention provides an organic wastewater treatment apparatus that leads to an improvement in treatment efficiency.
[0033]
Furthermore, the tower-type ozone contact tank facilitates decomposition when biologically treating organic wastewater containing organic components that are hardly decomposable generated by scrubbing exhaust gas containing an organic solvent. Therefore, it can contribute to the efficiency and compactness of the treatment process of organic wastewater generated in the food processing process in the food processing industry.
[0034]
[Problems to be solved by the invention]
In the conventional activated sludge method, the present invention makes it easy to purify even organic wastewater containing indegradable organic components, and the entire purification treatment equipment becomes compact, and installation costs, installation locations, and operating costs are also reduced. Provide organic wastewater treatment equipment that reduces and improves purification efficiency overall.
[0035]
[Means for Solving the Invention]
The invention according to claim 1 of the present invention is a mixing pump in which an organic drainage inflow pipe 8 is connected to the inflow side of the flow rate adjusting tank 1 to mix organic drainage, ozone, and an oxidation reaction accelerator into a mixed solution. 10 and the flow rate adjusting tank 1 are connected via a connecting pipe 9, and the organic component, ozone, and oxidation reaction accelerator contained in the mixed liquid fed from the mixing pump 10 and the mixing pump 10 are made more uniform. A tower type ozone contact tank 2 for contacting and mixing to completely oxidatively decompose the organic component is connected via a connection pipe 11, and the tower type ozone contact tank 2 and the aeration tank 3 are connected to a connection pipe 12. The aeration tank 3 and the aeration tank 4 are connected via a connection pipe 13, the aeration tank 4 and the precipitation separation tank 5 are connected via a connection pipe 14, and the precipitation A discharge pipe 16 for purified water is provided on the discharge side of the separation tank 5, and the above-mentioned glass is used for sludge reuse. A bottom of the sedimentation separation tank 5 and the bottom of the tank 3 connected via a sludge return pipe 15, the sludge return pump 21 is provided at an arbitrary position of the sludge return pipe 15 A jet nozzle 2b for injecting the mixed liquid in a circumferential direction in the tower ozone contact tank 2 is provided at an arbitrary position on the bottom inner wall of the tower ozone contact tank 2, A plurality of swivel guide plates 2a for swirling and raising the mixed liquid are provided at arbitrary positions inside. An organic wastewater treatment apparatus characterized by the above.
[0036]
The invention according to claim 2 of the present invention is the organic wastewater treatment apparatus according to claim 1, wherein ozone for injecting ozone for oxidizing and decomposing organic components contained in the organic wastewater is disposed at an arbitrary position of the mixing pump 10. This is an organic waste water treatment apparatus provided with an injection pipe.
[0037]
The invention according to claim 3 of the present invention is the organic wastewater treatment apparatus according to claim 1 or 2, wherein the organic wastewater is disposed at an arbitrary position of the connecting pipe 9 connecting the flow rate adjusting tank 1 and the mixing pump 10. The organic waste water treatment apparatus is provided with an oxidation reaction accelerator injection pipe 17 for injecting an oxidation reaction accelerator as a catalyst for promoting an oxidative decomposition reaction between an organic component contained in ozone and ozone.
[0040]
DETAILED DESCRIPTION OF THE INVENTION
The embodiment of the present invention will be described in detail with reference to FIGS.
[0041]
As shown in FIG. 1, an organic drainage inflow pipe 8 having an organic drainage inlet 6 is connected to the inflow side of the flow rate adjusting tank 1, and organic drainage, ozone and an oxidation reaction accelerator are mixed and mixed. The liquid mixing pump 10 and the flow rate adjusting tank 1 are connected via a connecting pipe 9, and organic components contained in the liquid mixture fed from the mixing pump 10 and the mixing pump 10, ozone and oxidation reaction promotion. A tower-type ozone contact tank 2 for completely oxidizing and decomposing the organic component by contacting and mixing the agent is connected via a connecting pipe 11, and the tower-type ozone contact tank 2 and the aeration tank 3 are connected to each other. Are connected via a connecting pipe 12, the aeration tank 3 and the aeration tank 4 are connected via a connecting pipe 13, and the aeration tank 4 and the precipitation separation tank 5 are connected via a connecting pipe 14. And a purified water discharge pipe 16 having a purified water discharge port 7 on the discharge side of the sedimentation separation tank 5. In order to reuse sludge, the bottom of the aeration tank 3 and the bottom of the settling tank 5 are connected via a sludge return pipe 15, and a sludge return pump is disposed at an arbitrary position of the sludge return pipe 15. 21 is provided.
[0042]
Next, an ozone injection pipe 18 for injecting ozone for oxidizing and decomposing organic components contained in the organic waste water is provided at an arbitrary position of the mixing pump 10.
[0043]
Next, ozone is injected from the ozone inlet 20 of the ozone injection pipe 18, and organic waste water and ozone are mixed by the mixing pump 10.
[0044]
At this time, an oxidation reaction accelerator injection pipe 17 having an oxidation reaction accelerator inlet 19 for injecting an oxidation reaction accelerator for accelerating the reaction between ozone and organic components in the organic waste water is connected to a flow rate adjusting tank. 1 and the mixing pump 10 are provided at arbitrary positions on the connecting pipe 9.
[0045]
The oxidation reaction accelerator is not particularly required, but the type and concentration of the oxidation reaction accelerator are appropriately determined depending on the type of organic component contained in the organic waste water.
[0046]
When using the above oxidation reaction accelerator, there is no particular limitation as long as it is effective in promoting the oxidation reaction of organic components contained in organic wastewater by ozone, but considering the cost, efficacy, and easy availability. Thus, it is preferable to use hydrogen peroxide as a catalyst.
[0047]
Further, the concentration of hydrogen peroxide added is preferably 3 ppm to 10 ppm with respect to the wastewater, although it depends on the nature of the organic wastewater.
[0048]
The ozone is a substance in which three oxygen atoms are chemically bonded. The greatest characteristic of the chemical nature of ozone is that the bond energy between atoms, that is, the dissociation energy is small.
[0049]
Therefore, ozone has the property of being easily decomposed. When ozone decomposes, oxygen atoms with extremely high oxidation reactivity are generated. This oxygen atom becomes a powerful oxidant.
[0050]
In recent years, the application range of ozone has been expanded because, even if ozone is used excessively in the oxidizing power of ozone and ozone treatment, the excess ozone becomes oxygen molecules and does not cause harm. However, ozone has an unpleasant odor peculiar to raw odors. If the concentration is high, it will irritate the mucous membrane of the nose and throat, so it must be handled with care.
[0051]
Moreover, ozone is used for the purpose of removing hardly decomposable organic components and chromaticity components that cannot be removed by biological treatment. In particular, it is effective for removing chromaticity components. That is, it selectively reacts with a double bond or special functional group related to color development in the molecular structure.
[0052]
Next, as shown in FIG. 2, the organic waste water containing the organic components sent from the mixing pump 10 and the mixed solution of ozone and the oxidation reaction accelerator are further uniformly contacted and mixed to completely oxidize and decompose the organic components. In order to do so, a jet nozzle 2 b that injects the mixed solution in a circumferential direction in the contact tank 2 is provided at an arbitrary position on the bottom inner wall of the tower-type ozone contact tank 2.
[0053]
Furthermore, a plurality of swivel guide plates 2a for swirling and raising the mixed solution from the bottom to the top of the contact tank 2 are provided at regular intervals at any position inside the tower type ozone contact tank 2.
[0054]
While the organic waste water containing the organic components injected in the circumferential direction in the contact tank 2 from the jet nozzle 2b, the mixed liquid of ozone and the oxidation reaction accelerator is stably drawn along the swirl guide plate 2a. It rises from the bottom in the contact tank 2 to the top.
[0055]
During this time, ozone comes into contact with the organic component in the mixed solution, and the ozone is attached to the intermolecular bond, and the oxygen atoms generated by the decomposition of the ozone cause an effective oxidizing action to easily decompose the organic component. Or a part decomposes | disassembles.
[0056]
This swirling flow is suitable for uniformly mixing organic wastewater containing organic components, ozone and an oxidation reaction accelerator, and maintaining the contact time. As the contact time elapses, the oxidative decomposition of the organic component by the oxygen atoms proceeds and finally decomposes into carbon dioxide gas and water.
[0057]
As an example of this action, an organic wastewater containing an organic compound having a carboxyl group may have the following reaction formula. 6R _- COOH + O _Three → 6R _- COO ^- + H ⁺ → Biodegradation → 6R '+ 6CO ₂ + 3H ₂ O → R "CO ₂ H ₂ O
[0058]
The ozone concentration relative to the organic waste water is appropriately determined depending on the organic components in the waste water, but is preferably 2 ppm to 15 ppm.
[0059]
Moreover, as shown in FIG.3 and FIG.4, when the water quality change by ozone aeration about the organic waste_water | drain containing ester type | system | group and a ketone type | system | group organic solvent as a hard-to-decompose organic component is measured, the said tower type ozone contact tank 2 is measured. It can be seen that the contact time of the organic waste water with ozone and the oxidation reaction accelerator is appropriately from 40 to 60 minutes, and if it is 30 minutes or less, it is difficult to obtain a sufficient effect.
[0060]
Next, the mixed solution flows into the first aeration tank in which the tower type ozone contact tank 2 is connected via the connection pipe 12. As an example, organic wastewater treatment provided from an aeration tank 3, an aeration tank 4, a sedimentation separation tank 5, and a sludge return pipe 15 having a sludge return pump 21, which are components of a conventional activated sludge process. Purified by the device.
[0061]
There are aerobic microorganisms in the aeration tank 3 and the aeration tank 4, and the aerobic microorganisms and the organic components in the waste water discharged from the tower ozone contact tank 2 are mixed and contacted.・ Oxidative decomposition of organic components in waste water in the presence of dissolved oxygen.
[0062]
The aerobic microorganism group is a microorganism that cannot act without air, that is, oxygen. This aerobic microorganism group is not only a single microorganism but also a mixture of many types of bacteria and protozoa.
[0063]
The action of the aerobic microorganism group is to first adsorb the soluble organic component in the wastewater in a short time, oxidatively decompose the soluble organic component by the microbial enzyme while consuming dissolved oxygen in the wastewater, and finally Breaks down into carbon dioxide and water.
[0064]
It is important that the oxygen supply necessary for the oxidative decomposition action that oxidizes the organic components of the aerobic microorganism group existing in the aeration tank 3 and the aeration tank 4 is sent to the aeration tank as small bubbles. is there. Small bubbles increase the contact area with water and increase the dissolution efficiency of oxygen in water.
[0065]
As an apparatus for sending air into the aeration tank 3 and the aeration tank 4, an aeration apparatus composed of a plate-like diffuser plate or a cylindrical diffuser cylinder made of a material such as ceramic or synthetic resin is used. Use.
[0066]
The air diffuser is installed at the bottom or lower part of the aeration tank 3 and the aeration tank 4, and air is fed by a blower. Small bubbles blowing up from the air diffuser give a swirling flow to the waste water in the aeration tank, the whole waste water is stirred, and oxygen is sufficiently supplied to the waste water.
[0067]
In the aeration apparatus, the aerobic microorganism group present in the aeration tank 3 and the aeration tank 4 supplies oxygen necessary for oxidative decomposition of the organic components in the organic waste water, and the aerobic microorganism group drains the organic component. It also serves the dual role of agitating the waste water so that the oxygen supplied inside can be taken in sufficiently.
[0068]
The oxygen dissolution efficiency between the oxygen fed by the air diffuser and the oxygen dissolved in the waste water is usually about 5% to 15%. In addition to the above-described small bubble diffuser, there are a “surface mechanical aeration method” or a “pure oxygen aeration method” using pure oxygen instead of air.
[0069]
The number of aeration tanks may be one or a plurality of aeration tanks depending on the inflow amount of organic waste water and the concentration of organic components in the organic waste water.
[0070]
The mixed solution of the aerobic microorganism group and the organic waste water discharged from the last aeration tank 4 flows into the next precipitation separation tank as it is. In the sedimentation separation tank, the mixed solution is not stirred and is in a stationary state, so the aerobic microorganism group aggregates and settles in a large lump, and only the purified supernatant is purified by the purified water discharge pipe 16 as purified treated water. It is discharged from the discharge port 7.
[0071]
The aerobic microorganism group (activated sludge) settled and concentrated in the settling tank is returned to the first aeration tank 3 by the sludge return pump 21 through the sludge return pipe 15.
[0072]
The returned sludge is used again for the oxidative decomposition of the organic components in the organic waste water. However, if the amount grown in this process is not removed outside the system, the whole balance cannot be achieved. If the sludge in the aeration tank 3 and the aeration tank 4 becomes too thick, the supply of oxygen may not be able to catch up.
[0073]
As described above, in the conventional activated sludge method, by newly installing the tower type ozone contact tank 2 between the flow rate adjusting tank 1 and the flash tank 3 of the organic waste water treatment apparatus, and adding chemical treatment in advance, Refractory organic components in organic wastewater can be completely purified, and large-scale aeration tank equipment in the conventional activated sludge method becomes compact, reducing installation costs, installation location, and operating costs. The present invention also provides an organic wastewater treatment device that leads to an improvement in purification efficiency.
[0074]
【Example】
Using the organic waste water treatment apparatus A in which the tower-type ozone contact tank 2 of the above invention is newly installed, ester-based and ketone-based organic solvents are used as refractory organic components in the organic waste water, and oxidative decomposition by ozone is performed. An effect is demonstrated based on an Example.
[0075]
<Example 1>
As shown in FIG. 1, an organic drainage inflow pipe 8 having an organic drainage inlet 6 is connected to the inflow side of the flow rate adjusting tank 1, and organic drainage, ozone and an oxidation reaction accelerator are mixed and mixed. The liquid mixing pump 10 and the flow rate adjusting tank 1 are connected via a connecting pipe 9, and organic components contained in the liquid mixture fed from the mixing pump 10 and the mixing pump 10, ozone and oxidation reaction promotion. A tower-type ozone contact tank 2 is connected through a connecting pipe 11 to further oxidatively decompose the organic component by uniformly contacting and mixing the agent, and the tower-type ozone contact tank 2 and the aeration tank 3 Are connected via a connecting pipe 12, the aeration tank 3 and the aeration tank 4 are connected via a connecting pipe 13, and the aeration tank 4 and the precipitation separation tank 5 are connected via a connecting pipe 14. And a purified water discharge pipe 16 having a purified water discharge port 7 on the discharge side of the sedimentation separation tank 5. In order to reuse sludge, the bottom of the aeration tank 3 and the bottom of the settling tank 5 are connected via a sludge return pipe 15, and a sludge return pump is disposed at an arbitrary position of the sludge return pipe 15. 21 was provided.
[0076]
Next, an oxidation reaction accelerator injection pipe 17 for injecting the oxidation reaction accelerator is provided at an intermediate position of a connection pipe 9 connecting the flow rate adjusting tank 1 and the mixing pump 10, and the pump body of the mixing pump 10 is further provided. An ozone injection pipe 18 for injecting ozone was provided at the top.
[0077]
Next, as shown in FIG. 2, in order to further uniformly contact and mix the mixed solution and completely decompose the hardly decomposable organic component, the mixed solution is brought into contact with the bottom inner wall of the tower type ozone contact tank 2. A jet nozzle 2b for jetting in the circumferential direction in the tank 2 was provided.
[0078]
Furthermore, while making the mixed solution swirl up from the bottom to the top in the tower-type ozone contact tank 2, the hardly decomposable organic component in the mixed solution, ozone and the oxidation reaction accelerator are contacted and mixed more uniformly. In order to completely decompose the hardly decomposable organic component, a plurality of swivel guide plates 2a are provided in the tower ozone contact tank 2 at equal intervals.
[0079]
Using the organic waste water treatment apparatus A as described above, organic waste water containing ester-based and ketone-based organic solvents, which are hardly decomposable organic components, is provided on the inflow side of the flow control tank 1. The water was introduced into the flow rate adjusting tank 1 from the organic drainage inlet 6 of the inflow pipe 8.
[0080]
Next, from the oxidation reaction accelerator injection port 19 of the oxidation reaction accelerator injection pipe 17 provided at an intermediate position of the connection pipe 9 connecting the flow rate adjusting tank 1 and the mixing pump 10, 5 ppm as an oxidation reaction accelerator. Hydrogen peroxide was injected.
[0081]
Furthermore, ester-based and ketone-based organic solvents in organic wastewater are oxidatively decomposed from an ozone inlet 20 of an ozone injection pipe 18 for injecting ozone provided at the upper part of the pump body of the mixing pump 10. 10 ppm of ozone was injected.
[0082]
Next, the mixed pump 10 sufficiently mixes organic waste water containing ester-based and ketone-based organic solvents, which are hardly decomposable organic components, with ozone and hydrogen peroxide, which is an oxidation reaction accelerator, and the mixed solution. The mixed liquid was jetted in the circumferential direction in the contact tank 2 from the jet nozzle 2b provided on the inner wall of the bottom of the tower type ozone contact tank 2 connected to the mixing pump 10 via the connecting pipe 11. .
[0083]
Next, a plurality of turning guide plates 2a provided at equal intervals inside the tower type ozone contact tank 2,
While making the mixed solution swirl upward from the bottom to the top, the ester-based and ketone-based organic solvent, ozone, and hydrogen peroxide, which is an oxidation reaction accelerator, in the mixed solution are more evenly distributed. Contact mixed.
[0084]
The ozone aeration experiment was repeated at a rate of 20 to 30 mg per minute per liter of organic wastewater containing ester-based and ketone-based organic solvents that are hardly decomposable organic components in the organic wastewater.
[0085]
As shown in FIG. 3 and FIG. 4, the average value of BOD value and COD value in organic waste water decreases with the elapsed time of ozone aeration, and is clearly an ester that is a hardly decomposable organic component in organic waste water. It was measured that the intermolecular bonds of the system and the ketone organic solvent were oxidatively decomposed by ozone.
[0086]
The BOD of the BOD value is an acronym for Biochemical Oxygen Demand and is a numerical representation of the degree of contamination of water contaminated with soluble organic matter such as domestic wastewater. Since it is impossible as a real problem to analyze all the components of dirt, it is one indicator that has been proposed as a display method that can grasp the whole greatly. If the number is small, it is clean water, and if it is large, it is dirty water.
[0087]
BOD is JIS K0102 factory wastewater test method: “Biochemical oxygen consumption means the amount of dissolved oxygen consumed by aerobic microorganisms in water. Dilute the sample with diluted water and leave it at 20 ° C. for 5 days. It is expressed as “the amount of dissolved oxygen consumed when left untreated”. Of course, even a soluble organic substance is not detected if it is not decomposed by microorganisms, such as a water-soluble synthetic polymer.
[0088]
Next, COD of the COD value is an acronym for Chemical Oxygen Demand, and chemicals called oxidizing agents are used without using microorganisms. It is intended to represent how dirty sewage is expressed by quantifying how much oxygen is consumed.
[0089]
In Japan, the measurement of the COD value employs a method in which potassium permanganate is used as an oxidizing agent and the reaction is carried out at 100 ° C. for 30 minutes under sulfuric acid acidity.
[0090]
【The invention's effect】
In the conventional activated sludge method, by installing a tower-type ozone contact tank between the flow control tank and the aeration tank as a pretreatment facility, purification treatment can be easily performed even for organic wastewater containing persistent organic components. In addition, the overall equipment becomes compact, the installation cost, the installation location, and the operation cost are reduced, and the efficiency of the purification process is improved as a whole.
[Brief description of the drawings]
FIG. 1 is a basic configuration diagram of an organic wastewater treatment apparatus A according to the present invention.
FIG. 2 is a schematic diagram showing the principle in a tower-type ozone contact tank provided with a jet nozzle for injecting a mixed liquid and a plurality of swiveling guide plates for contact mixing of the mixed liquid in the organic waste water treatment apparatus according to the present invention. .
FIG. 3 is a chart showing a decrease and a decrease rate due to ozone aeration of a BOD value of organic waste water containing an ester-based and ketone-based organic solvent in the organic waste water treatment apparatus according to the present invention.
FIG. 4 is a chart showing a decrease and a decrease rate of COD values of organic waste water containing an ester-based and ketone-based organic solvent by ozone aeration in the organic waste water treatment apparatus according to the present invention.
FIG. 5 is a basic configuration diagram of an organic wastewater treatment apparatus according to the prior art.
[Explanation of symbols]
A ... Organic wastewater treatment apparatus of the present invention
B ... Conventional organic wastewater treatment equipment
1 ... Flow adjustment tank
2 ... tower type ozone contact tank 2a ... swivel guide plate 2b ... jet nozzle
3 ... Aeration tank
4 ... Aeration tank
5 ... Sedimentation separation tank
6 ... Organic drainage inlet
7 ... Purified water outlet
8 ... Inflow pipe for organic drainage
9 ... Connection pipe
10 ... Mixing pump
11 ... Connection pipe
12 ... Connection pipe
13 ... Connection pipe
14 ... Connection pipe
15 ... Sludge return pipe
16 ... Purified water discharge pipe
17 ... Oxidation reaction accelerator injection tube
18 ... Ozone injection tube
19 ... Oxidation reaction accelerator inlet
20 ... Ozone inlet
21 ... Sludge return pump

Claims (3)

Connect the inflow pipe for organic drainage to the inflow side of the flow rate adjustment tank, and connect the flow rate adjustment tank to the mixing pump that mixes organic drainage, ozone, and oxidation reaction accelerator to make a mixture. And the organic component contained in the mixed liquid fed from the mixing pump and the mixed pump, ozone and an oxidation reaction accelerator are more uniformly contacted and mixed to completely oxidatively decompose the organic component. A contact tank is connected via a connection pipe, the tower-type ozone contact tank and an aeration tank are connected via a connection pipe, the aeration tank and the aeration tank are connected via a connection pipe, The aeration tank and the precipitation separation tank are connected via a connecting pipe, a discharge pipe for purified water is provided on the discharge side of the precipitation separation tank, and the bottom of the aeration tank and the precipitation are used for sludge reuse. Connect the bottom of the separation tank to the sludge return pipe at any position. The mud return pump provided at an arbitrary position of the bottom inner wall of the tower ozone contact tank, a jet nozzle for injecting the mixture in the circumferential direction of the column ozone contact tank provided, said column ozone contact An organic wastewater treatment apparatus characterized in that a plurality of swivel guide plates for swirling and raising the mixed liquid are provided at equal intervals in any position inside the tank .   2. The organic wastewater treatment apparatus according to claim 1, wherein an ozone injection pipe for injecting ozone for oxidizing and decomposing organic components contained in the organic wastewater is provided at an arbitrary position of the mixing pump. Wastewater treatment equipment.   The organic waste water treatment apparatus according to claim 1 or 2, wherein an oxidative decomposition reaction between ozone and an organic component contained in the organic waste water is performed at an arbitrary position of a connection pipe connecting the flow rate adjusting tank and the mixing pump. An organic wastewater treatment apparatus provided with an oxidation reaction accelerator injection pipe for injecting an oxidation reaction accelerator as a catalyst to be promoted.

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