KR100191865B1 - Biological and aerobic disposal apparatus and its method of wastewater with closed-type - Google Patents

Abstract

One or two or more reactors operated by the countercurrent flowing the wastewater from the bottom by introducing the wastewater from below, and one or more injuries that can decompose organic matter in the wastewater as microorganisms are attached and grow in the reactor. Of the media and one or more strainers installed to suppress the passage of the flotation media in the reactor and selectively allow only the treated water to pass through, and a static mixer and a dissolved oxygen that completely mixes pure oxygen and wastewater. Biological treatment devices for wastewater and wastewater, including a pure oxygen supply system that allows the use of pure oxygen instead of air to increase the concentration, and an automatic operation system that automatically regulates normal and backwash operations, 1.0-3.0 Kg / ㎠ When operating at G pressure, biochemical oxygen demand (BOD), an indicator of organic pollutants, is reduced to 5 The present invention relates to a wastewater treatment apparatus by biofilm filtration that can be removed up to mg / l and a method thereof.

Description

Fully enclosed aerobic wastewater biological treatment device and method

[Industrial use]

The present invention relates to a biological treatment apparatus for wastewater, and more particularly, a new type of biological treatment capable of economically and effectively removing organic pollutants (BOD) and suspended solids (SS) present in sewage or wastewater. A device and a method thereof are described.

[Prior art]

Impurities or contaminants present in raw or waste water can be treated by physical, chemical or biological treatment methods. Among the above methods, the physical treatment method is a method of removing contaminants through unit operations such as screening, precipitation, flotation, filtration, and adsorption, and the chemical treatment method is chemical oxidation / reduction, chemical precipitation, sterilization, flocculation, incineration, etc. It is a method of removing contaminants through unit chemical reaction. On the other hand, the biological treatment method is a method of removing organic matter decomposable by living organisms using microorganisms, plants, and the like. The concentration of organics, ie organic contaminants, is often expressed as BOD, a biochemical oxygen demand. As a biological treatment method for removing such organic contaminants, that is, BOD, a representative conventional technique is a biological treatment method using activated sludge shown in FIG. As a whole, the wastewater treatment process using the activated sludge tank as shown in FIG. 4, after storing the influent water through the screen tank in the flow storage tank, removes the organic matter from the activated sludge tank and finally settles the tank. It consists of the process of sedimenting sludge contained in the treated water and returning a part of it to the activated sludge tank and finally disinfecting and discharging the supernatant of the sedimentation tank. At this time, the activated sludge, which plays a key role in the biological treatment device, is a reactor made of a concrete structure, and contains a microorganism mass called activated sludge inside, and these microorganisms multiply by using dissolved oxygen dissolved in the wastewater and organic contaminants. Is used as a nutrient to decompose and remove organic contaminants. However, such activated sludge has a disadvantage that the degree of containing microorganisms is limited and active sludge takes up a lot of space. In addition, the agglomerates of microorganisms proliferated in the activated sludge are settled and discharged from the settling tank, which is a subsequent process, and the settling tank also has a problem of occupying a large space. When the load fluctuation of the wastewater is severe, the treatment efficiency is extremely low, and because of the aerobic treatment, the apparatus is exposed to the outside, causing a lot of odors.

Various methods have been tried as a method for solving the problem of the activated sludge as described above. First, to reduce the space occupied by activated sludge process, various variations have been developed to fill the activated sludge with various media so that the microorganisms adhere to and grow as many microorganisms as possible. There are many restrictions on storing microorganisms above a certain level, and there are many operational difficulties in making many microorganisms effective. In order to solve various problems of the activated sludge process, various types of biological treatment apparatuses have been developed and attempted, and these improved types do not exhibit satisfactory treatment capabilities.

Table 1 below shows the BOD volume loads of commonly known aerobic biological treatment devices, including activated sludge. At this time, the BOD volume load means the amount of BOD load (kg BOD / ㎥ · day) that can be processed per day in the volume of 1㎥ of the reactor, and the larger the BOD volume load, the smaller the size of the microbial reactor. BOD volume load is 0.4 ~ 0.8kg BOD / ㎥ · day for activated sludge tank and BOD volume load does not exceed 1.4kg BOD / ㎥ · day even for contact stabilizer with improved activated sludge treatment. It can be seen that the efficiency is low and a large capacity apparatus is required to treat a large amount of wastewater.

The present invention has been made to solve the problems of the prior art as described above, an object of the present invention is to provide a novel wastewater biological treatment device having a very small required area of the device and very excellent wastewater treatment efficiency. Second, to provide a new biological treatment device of wastewater with excellent treatment efficiency even in the case of high load and heavy load fluctuations, and third, to provide a novel biological treatment device for wastewater with no odor emission and biological deodorization. Fourthly, unmanned automation is possible, so it is easy to operate and manage, and it is used semi-permanently, thus providing a new economical biological treatment device for wastewater, which is economical.

1 is a process diagram schematically showing a process for treating wastewater by using a biological treatment apparatus for wastewater according to the present invention.

2 is an apparatus diagram schematically showing an apparatus for treating wastewater using a biological treatment apparatus for wastewater according to the present invention.

3 is a cross-sectional view schematically showing a biological treatment apparatus for wastewater according to the present invention.

4 is a process diagram schematically showing a process of treating wastewater using a conventional activated sludge tank.

[Configuration of the present invention]

In order to achieve the object of the present invention as described above, the present invention is a reactor for introducing waste water into the upstream from the bottom and out of the treated water, and the floating filling in the reactor, while the microorganism is attached and grown Biological wastewater treatment apparatus comprising a flotation media capable of decomposing valuables in the wastewater, and one or more strainers installed in the reactor to suppress the passage of the flotation media and allow only the treated water to move upwards. to provide.

In the present invention described above, the material of the container is preferably selected from the group consisting of stainless steel, carbon steel or resin.

In the present invention described above, the above-mentioned floating media is preferably a foam having a specific surface area of 400 to 3,000 m 2 / m 3, and the floating media are preferably made of one selected from the group consisting of polyethylene, polypropylene, and polystyrene. .

In the present invention described above, it is preferable that the pressure in the reactor is 1 to 3 kg / cm 2 G.

In the present invention, it is preferable that the waste water and waste water are mixed with oxygen using a gas-liquid mixer, or further include an oxygen supply device for supplying oxygen into the reactor.

In the present invention described above, it is preferable to further include a backwashing device installed above the floating media in order to discharge the sludge in the reactor.

In addition, the present invention, the waste water is introduced into the reactor in an upflow, the organic material of the introduced waste water is decomposed by the microorganisms of the flotation material present in the reactor, the treated water from which the organic material is removed The present invention provides a method for biological treatment of sewage and wastewater, which includes a step of moving up and out of a strainer to prevent passage of the floating media by upflow.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings. However, the following exemplary embodiments are only preferred embodiments of the present invention to aid the understanding of the present invention, and the present invention is not limited to the following examples.

1 is a process diagram schematically showing a process of treating waste water by the waste water treatment apparatus of the present invention. In the conventional biological treatment method, although the activated sludge tank and the settling tank are connected to the rear end of the flow control tank as shown in FIG. 4, in the biological treatment method according to the present invention, the activated sludge tank and the settling tank are shown in FIG. Instead, only the biofilter of the present invention, which is a compact biological treatment apparatus as shown in FIG. 3, needs to be installed. That is, in this process, the waste water to be treated is first removed from the screen tank by 2 mm or more, and then introduced into the biofilter of the present invention, and organic contaminants attached to the media are decomposed using the growing microorganisms and then treated as treated water. Discharged.

As shown in FIGS. 2 and 3, the biofilter 4, which is a biological treatment device of the present invention, fills the floating filter layer 5 that provides a surface where microorganisms can adhere and grow, as shown in FIGS. Sewage and waste water flows in from the bottom of the biofilter upwards and passes through the flotation bed to be purified. In addition, the strainer 6 is installed at a predetermined interval so that only the purified water can pass through the filter medium without passing through the filter medium, and the water passing through the biofilter is sent to the next process while being stored in the treatment tank 7 or through a sterilization tank. Final discharge. According to the present invention, organic contaminants are purified using the flotation filter filled as described above, and several biofilters may be installed in a row or in parallel according to a target value of BOD to be treated. The volumetric load of the biofilter of the present invention can handle 1.0-10.0kgBOD per 1m 3 of floating media, so the BOD volume load is very large, and when the biological treatment device of the present invention is used, the wastewater can be purified to 5 ppm or less of BOD. Can be.

The biofilter reactor of the present invention described above may be made of stainless steel or carbon steel, and in some cases, it is possible to add a thermal insulation facility. Floating media is made of polystyrene-based materials and uses a specific surface area of about 2,000㎡ / ㎥. At this time, in order to maximize the decomposition activity of microorganisms inhabiting the floating media by providing oxygen to the microorganisms in the biofilter, air or pure oxygen is mixed and dissolved with waste water at high speed using a gas-liquid mixer (3), and then the biofilter It is preferable to inject in. At this time, it is preferable to introduce the waste water into the biofilter, which is a biological treatment device of the present invention, at a pressure of 1.0-3 Kg / cm 2 G. In particular, oxygen (8) is supplied instead of air and 1.0 to 3.0 Kg / cm 2 G system is introduced. When pressure is applied, sufficient oxygen is dissolved in water and mixed with wastewater and then injected into the biofilter to maximize the decomposition effect of organic contaminants. In addition, when oxygen is supplied in a dissolved state, it can be operated in a completely enclosed state to suppress the occurrence of odors and also remove odors in wastewater through microbial filtration.

On the other hand, the fine sludge contained in the microbial sludge and inflow water grown in the biofilter, but stuck to the biofilter due to the filtration function of the biofilter, uses the backwash pump 8 to drain the water from the treatment tank 7 to the upper part of the biofilter. It is poured at a high speed from the lower part to the lower part and expands the floating media, periodically shakes it off, and discharges it to the outside. In this way, the biofilter of the present invention exhibits a purification function while continuously maintaining an optimal microbial state. The backwashing of the biofilter of the present invention preferably uses treated water, and the backwashing time is 2-3 minutes, which is very short compared to 20 minutes, which is the backwashing time of a similar device, and is easy to backwash.

EXAMPLE

Hereinafter, preferred embodiments of the present invention will be described. However, the following examples are only preferred embodiments of the present invention to aid in understanding the present invention, and the present invention is not limited to the following examples.

Example 1

Purification experiments were performed on sewage with a BOD of 200-250 mg / l using the biofilter having the structure shown in FIG. 4, and the results are shown in Table 2 below. The experiment was carried out by varying the amount of BOD load (kgBOD / ㎥ media) that can be processed per day per 1㎥ of media, which allowed the microorganisms to adhere to the media by growing sludge for the first 15 days. After 7 days of experimental results are shown.

As can be seen from Table 2, when the biofilter of the present invention is used, when the BOD volume load is 2 (kg BOD / m 3 · media · day), the BOD of the effluent is treated very well as 2 to 10 mg / l. Even when the BOD volume loading was 5.0 (kg BOD / ㎥ · media · day), it was treated stably in the range of 30-50 mg / l. This can be seen that the existing activated sludge method is very effective when compared to the BOD 20 ~ 100mg / ℓ at 0.3 ~ 0.8kgBOD / ㎥ · day per ton BOD volume loading. The large volume load means that the installation area of the device is much more economical.

Example 2

Using the biofilter having the structure shown in FIG. 4, the effluent water according to the operation time when the sewage with BOD of 30 to 140 mg / l was treated with a BOD load of 2.0 which can be treated per day per 1m 3 of the media was 2.0. The results of analyzing the BOD are shown in Table 3 below.

As shown in Table 3, the biofilter operation of the present invention showed that after 3 days of operation, the BOD concentration of the effluent was analyzed to 10 mg / l or less, and after 10 days, it was treated up to 2 mg / l and continuously 5 mg. It was treated very stably up to / l.

As described above, the present invention promotes the attachment of microorganisms to the floating media layer filled inside the biofilter in the aerobic oxidative decomposition of contaminants by the fully enclosed biofilter, and the microorganism decomposes to the maximum. A device designed to enable high pressure dissolution of pressure filtration and oxygen so as to purify the same, and when using the biological treatment device of the present invention, it is possible to stably treat organic pollutants to BOD 5 mg / l or less. It is very useful in that it can very effectively remove contaminants from domestic sewage, sewage, and wastewater containing many organic components.

As such, the present invention significantly improves the treatment efficiency of conventional activated sludge treatment methods and other variations, so that the maximum microorganisms are capable of purifying as much as possible, and all microorganisms effectively decompose even if the amount of microorganisms is large. Not only is the site area required for microbial treatment reduced dramatically, but also the purification and processing equipment can be operated very conveniently because the operation of the apparatus and process is automated.

Advantages of the waste water treatment according to the present invention are as follows.

-The volume load can handle 1.0 ~ 10.0kgBOD per 1㎥ of floating media, so the BOD volume load is very large. Therefore, a compact biofilter is installed in place of the activated sludge tank and the settling tank installed in the aerobic activated sludge process. Due to the simplicity of construction, the site area is greatly reduced.

-High concentration of microorganisms are propagated in the filter media inside the biofilter, so the processing efficiency is high and stable even under high load and heavy load fluctuations.

-It is designed to be completely enclosed, so no odor is discharged out of the system and biological deodorization is possible, so no odor is emitted.

-It is easy to operate and manage by automating the device so that it can be operated unattended.

-The media can be used semi-permanently once it is filled, so the maintenance cost is hardly incurred.

-Backwashing of biofilters uses treated water and backwashing time is a few minutes, so backwashing time of similar devices is very short compared to 20 minutes, so backwashing is efficient.

Claims (8)

A reactor for introducing the waste water into the upstream from the bottom and outflow of the treated water; One or more flotation media which are flotation in the reactor, which can decompose organic matter in the waste water while microorganisms are attached and grown; One or more strainers installed to inhibit passage of floating media in the reactor and to allow only the treated water to selectively move upwards; A pipe and pump device for controlling the wastewater inflow and the treated water outflow; And a device capable of backwashing to discharge sludge in the reactor. The biological treatment apparatus according to claim 1, wherein the reactor material is selected from the group consisting of stainless steel, carbon steel or resin. The biological treatment apparatus according to claim 1, wherein the flotation medium is selected from the group consisting of polyethylene, polypropylene, and polystyrene, and has a specific surface area of 400-3,000 m 2 / m 3. The biological treatment device of claim 1, wherein the pressure in the reactor is 1.0-3.0 kg / m 2 G. The biological treatment apparatus according to claim 1, wherein the waste water is mixed with oxygen or air using a static liquid mixer. The biological treatment device of claim 1, further comprising a device for supplying oxygen or air into the reactor. Introducing waste water into the reactor upstream; The organic material of the introduced waste water is decomposed by the microorganisms on the floating media present in the acid reactor; The treated water from which the organic material has been removed flows out of the strainer to prevent passage of the floating media by upflow; Outflowed treated water is stored in the treatment tank; Biological treatment method of wastewater, including the process of flowing the treated water from the treatment tank into the downflow at a constant pressure from the upper part of the reactor by backwashing the floating filter material, and backwashing the floating filter material to remove sludge from the floating filter bed. . The biological treatment apparatus according to claim 1, further comprising a treatment tank capable of storing the treated water passing through the reactor.