JPH07275900A - Method for treating wastewater containing organic substance - Google Patents

Abstract

PURPOSE:To efficiently remove harmful substances by carrying out solid-liquid separation for wastewater containing a large amount of organic substances, and then introducing the filtered liquid of the wastewater into a polymerizing apparatus, mixing the filtered liquid with ozone, and then carrying out oxidoreduction reaction in a reaction tank. CONSTITUTION:After wastewater from a water tank 1 is separated into solid matter and a separated liquid by solid-liquid separating apparatuses 3, 6, the solid matter is dehydrated by a dehydrator 8 and then converted into a fertilizer or used for reclamation. The filtered liquid is sent to a polymerizing apparatus via a filtered liquid storage tank 11, and while bubbles being generated by air sent from an air compressor 13 and a forced draft fan 14, an oxidizing agent, a neutralizing agent, a flocculating agent are added to carry out flocculation and flock formation. The produced flocks are coagulated and precipitated in a coagulating and precipitation tank 15, the obtained treated water is introduced into a reaction tank 17, sprayed in superfine particle state, and irradiated with ultraviolet rays 36 to oxidoreduce suspended substances and malodorous components for removing them. Further, the remaining suspended substances and malodorous substances are catalytically reacted with sodium hypochlorite or ozone in a catalytic oxidization tower 19 to be removed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water treatment facility, and relates to a method for treating wastewater containing a large amount of organic substances.

[0002]

2. Description of the Related Art A conventional wastewater treatment method has relatively little variation in the quality of wastewater and can be treated relatively easily. Therefore, at present, the activated sludge method using microorganisms is the mainstream. This activated sludge process is one of aerobic treatments and is suitable for wastewater containing an organic substance having a low BOD (biochemical oxygen demand) load. In this treatment method, organic-containing wastewater is screened and coarse contaminants and solids are removed by sedimentation in a sedimentation basin, and then the overflow water is guided to an aeration tank, and returned sludge is added as a microorganism seed and aerated for several hours. During this period, various aerobic microorganisms in the wastewater rapidly grow and undergo chemical, physical and biological changes such as oxidation, adsorption and aggregation (floc formation). After that, when it is left to stand in a sedimentation pond, it is separated into clear water and sediment. This sludge is called activated sludge, and part of it is re-aerated and used as seed sludge for seeding, but the rest is used as fertilizer after drying with water as excess sludge. Most of them require reprocessing by incineration or landfill. Further, anaerobic treatment by methane fermentation is performed in which a waste water is digested for about 30 days in a digestion tank while keeping the waste water at 30 to 37 ° C. However, the generated sludge requires the same treatment and disposal as the aerobic treatment method. This activated sludge method is effective for treating wastewater having a not so high BOD (about 500 ppm or less). The high BOD wastewater is generally treated by an activated sludge method after anaerobically treating or diluting it or removing BOD to some extent by other methods. However, the amount of sludge generated by this treatment continues to increase, and various problems frequently occur because it is very difficult to treat and dispose of this sludge. Conventionally, as mentioned above, a part has been used as landfill, improvement of agricultural land after dehydration and drying, and fertilizer, but it is not always appropriate when considering the characteristics of the sludge itself and geographical conditions, etc. as the amount of generation increases. The method is not good.

[0003]

DISCLOSURE OF THE INVENTION The present invention provides a conventional method for treating wastewater containing a large amount of organic substances in a simple and safe manner.
To reduce the huge equipment costs and maintenance costs of conventional wastewater treatment facilities, as well as to convert them into economical, hygienic and harmless final products.

[0004]

DISCLOSURE OF THE INVENTION The present invention relates to a method for treating wastewater containing a large amount of organic substances in Japanese Patent No. 15340.
No. 61, No. 1594104, No. 1618609, based on No. 61, No. 1618609, ozone (O ₃ ) and oxygen atoms (O) generated by pretreatment (hereinafter referred to as solid-liquid separation) (hereinafter, filtrate). It is solved by the treatment by detoxification by making it react with the redox. In the solid-liquid separation process, it is separated into a solid matter and a filtrate, and the solid matter is dehydrated and then used for fertilization or landfill disposal. On the other hand, the latter filtrate, while flowing into the polymerization device (a pressure cooker or a spur tube that forms a swirl flow), simultaneously sent 5 to 8 kg / cm ² G of compressed air, and still sent it by a forced air blower. After air bubbles are generated by air, the pH is adjusted to about 4 with an oxidizing agent, the pH is returned to 7 with a neutralizing agent, flocs are formed by adding a flocculant, and the flocculate-precipitated solid matter is generated in the solid-liquid separation process. Merge and process. The separated overflow water (filtrate) is ozone (O ₃ ).
By pre-mixing with, by spraying ultrafine particles in the reaction tank and then irradiating with ultraviolet rays, the suspended matter and odor contained in the filtrate are rapidly oxidized and reduced to be removed, By further reacting with oxygen atoms (O), the remaining suspended solids and odors are quickly redox-removed and removed, and the odorous air generated in the solid-liquid separation process is collected and mixed with ozone to be oxidized. It is intended to efficiently and inexpensively provide a treatment method for removing harm by reduction. The solid-liquid separation treatment method is to add a flocculant in the raw wastewater tank in the solid-liquid separation process and then quickly aerate to form flocs, and then install a separator with a special net conveyor in two stages. Since the solid waste and the filtrate can be easily separated by spontaneously dropping the raw wastewater, the load of suspended substances contained in the filtrate can be reduced, and therefore the subsequent treatment can be performed very easily. After the separated overflow water (filtrate) is mixed with ozone, it is irradiated with ultraviolet rays and rapidly oxidized and reduced to drastically reduce the load of pollutants contained in the filtrate, and then the catalyst and hypochlorous acid are further added. React with sodium chlorate or ozone to generate oxygen atoms and react quickly with the filtrate,
While removing the remaining pollution by redox,
The odorous air generated during the solid-liquid separation process is collected and mixed with ozone to be redox-removed.

[0005]

[Operation] After solid-liquid separation of wastewater containing a large amount of organic substances, it is allowed to flow into the polymerization equipment, and then the filtrate is mixed with ozone and then subjected to an oxidation-reduction reaction in a reaction tank. Remove the remaining pollution qualities.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the processing method of the present invention will be described with reference to FIG. 1 is a systematic diagram showing the concept of a method for treating wastewater containing a large amount of organic substances and having a high BOD concentration. First, raw wastewater a flows into a raw wastewater tank 1, but an air diffuser 2 is provided at the bottom of the tank 1. While appropriately stirring the raw wastewater a with the air b, the flocculant c was appropriately added to form flocs in the tank 1. 1 Special N installed in solid-liquid separator 3
o. 1 Transfer to the net conveyor 4. The conveyor 4 is
It has a structure (not shown) that can select a special mesh according to the situation of flock formation of the raw wastewater a and also adjust the conveyor speed according to the situation of flock formation. Here, solid matter (hereinafter referred to as sludge) d and desorbed liquid (hereinafter referred to as filtrate) e are separated by gravity falling in a natural state, and sludge d is diffused by a diffusing pipe 2 provided at the bottom of the relay tank 5.
The air b is fed to the sludge d and the sludge d is stirred appropriately while the coagulant c
Was added to form flocs, and then No. 2 Solid-liquid separator 6
Special No. 2 Transfer to the net conveyor 7. Here, No. 1 The same operation as the solid-liquid separator 3 is repeated,
It is separated into sludge d and filtrate e. The separated sludge d is transferred to the dehydrator 8 and then subjected to strong dehydration to obtain a water content of 70.
% Or less sludge and separated into filtrate e. The filtrate e generated at the above-mentioned three places is transferred to and stored in the filtrate storage tank 11. One sludge d is a carrier (not shown)
The sludge is stored in the sludge storage tank 9 by means of a fixed quantity slicing machine 10 provided at the bottom of the tank 9 and then carried out to the outside of the site. The filtrate e stored in the filtrate storage tank 11 flows into the spur tube 12 that forms a swirl flow, and at the same time, compressed air b ′ of 5 to 8 kg / cm ² G is supplied to the air compressor 13.
Air is further supplied and air is generated by the forced air blower 14 to generate air bubbles, the pH is adjusted to about 4 with the oxidizing agent g, the pH is returned to 7 with the neutralizing agent h, the coagulant c is added, and the mixture is instantaneously added. After the mixing is completed, water is sent to the flocculation sedimentation tank 15, where flocs are formed and the flocculated sedimentation sludge d ′ is formed.
Is combined with the sludge d generated in the solid-liquid separation process and treated by the method as described above. On the other hand, overflow water (filtrate) e
Is stored in the filtration waste water tank 16 and is sequentially mixed with ozone j generated by an ozone generator (not shown), and then the reaction tank 17
Ultrafine particles are sprayed inside, and ultraviolet rays 18 are irradiated there to rapidly remove the suspended matter and odor contained in the filtrate e by redox fitting. Further, in the oxidation catalyst tower 19, sodium hypochlorite i or ozone j is reacted with the catalyst k filled in the tower 19 to generate oxygen atoms o, which are reacted with the filtrate e to remain in the filtrate e. After the suspended matter and the odor are rapidly redox-removed and stored in the treated water tank 20,
The treated water e ′ is appropriately discharged, but when the catalyst k packed in the oxidation catalyst tower 19 is washed, it is used as backwash water.
The backwash wastewater m used for cleaning is sent to the filtrate storage tank 11 for reprocessing. Further, odorous air generated during the solid-liquid separation process of the treatment method is collected and mixed with ozone j for redox removal.

[0007]

INDUSTRIAL APPLICABILITY The present invention separates a solid matter and a desorbed liquid, can stabilize the quality of treated water and render it harmless, and can completely prevent natural destruction by treated water. It is extremely efficient compared to the activated sludge method, the construction cost of the treatment equipment can be significantly reduced, the same result can be obtained in terms of running cost, and the labor cost is also different from the conventional treatment method. It is an extremely excellent thing that cannot be expected from the law.

[Brief description of drawings]

FIG. 1 is a conceptual system diagram showing an undiluted wastewater treatment method according to an embodiment of the present invention.

[Explanation of symbols]

1 ... Raw waste water tank, 2 ... Air diffuser, 3 ... No. 1 solid-liquid separator, 4 ... No. 1 Net conveyor 5 ... Relay tank, 6 ... No. 2 solid-liquid separator, 7 ... No. 2 Net conveyor, 8 ... Dehydrator, 9 ... Sludge storage tank, 10 ... Fixed amount cutting machine, 11 ... Filtration storage tank, 12 ... Spar tube, 13 ... Air compressor, 14 ... Push blower, 15 ... Coagulation sedimentation tank, 16 ... Filtration wastewater tank, 17 ... Reaction tank, 18 ... Ultraviolet ray, 19 ... Oxidation catalyst tower, 20 ... Treatment water tank, a ... Raw wastewater,
b ... air, b '... compressed air, C ... flocculant, d ... sludge,
d '... precipitated sludge, e ... filtrate, e' ... treated water, g ... oxidizer, h ... neutralizer, i ... sodium hypochlorite, j ... ozone,
k ... catalyst, m ... backwash wastewater, o ... oxygen atom,

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location C01B 13/10 D C02F 1/32 ZAB 1/52 ZAB K 1/58 ZAB G 1/76 ZAB Z 1/78 ZAB 9/00 502 D N PR Z 503 C 504 B C05F 7/00 301 H 7537-4H

Claims (1)

[Claims] 1. A wastewater containing a large amount of an organic substance is subjected to a pretreatment (hereinafter referred to as solid-liquid separation) to obtain a solid matter (hereinafter referred to as a solid matter).
It is called sludge. ) And desorbed liquid (hereinafter referred to as filtrate), and the solid matter is dehydrated and then used as a fertilizer or landfill.
On the other hand, the filtrate flows into the polymerization device (a pressure cooker or a spur tube that forms a swirl flow) at the same time as 5 to 8 kg.
/ Cm ² G of compressed air is blown, and air is blown by a forced air blower to generate air bubbles. After pH is adjusted to about 4 with an oxidizing agent, the pH is returned to 7 with a neutralizing agent, and a flocculant is added to cause aggregation. (Floc is formed) The solid matter that has been flocculated and precipitated is combined with that generated in the solid-liquid separation process, and the overflow water, which is the filtrate, generates oxygen (O ₂ ) from air by an oxygen production device. Then, ozone (O ₃ ) is generated by this oxygen by an ozone generator, the ozone is mixed with the filtrate, and then atomized into ultrafine particles in a reaction tank, and ultraviolet rays are irradiated to form a suspended substance. The odor is removed immediately by redox. Further, in the oxidation catalyst tower, sodium hypochlorite (NaOCl) or ozone is contact-reacted with the catalyst packed in the tower to generate oxygen atoms (O), and the suspended matter remaining by reacting with the filtrate is obtained. And the odor are quickly redox-removed and removed, and the odorous air generated during the solid-liquid separation process is collected and mixed with ozone to be redox-removed and removed. Wastewater treatment method.