KR20150085990A - Water and wastewater treatment system and metho of the same - Google Patents

Abstract

The present invention discloses a sewage and waste water processing system. The sewage and waste water processing system includes: an MBR unit including an anaerobic tank, a stabilization tank, an anoxic tank, an aerobic tank, and a submerged membrane tank; an RO film module which is arranged on the rear end of the MBR unit, separates the organic matters dissolved in the water processed by the MBR unit, and stores the dissolved organic matter; an ozone reaction tank which is connected to the condensed water discharging port of the RO film module, stores the condensed water, and injects ozone into the condensed water.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wastewater treatment system,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wastewater treatment system, and more particularly, to a wastewater treatment system using MBR and RO processes and a treatment method thereof.

In general, the treatment methods for sewage and wastewater can be roughly divided into physical methods, chemical methods and biological methods, and each treatment method is determined by the characteristics of the sewage to be introduced, the use of the treated effluent, .

The physical and wastewater treatment methods are selectively used such as ammonia removal by air removal, filtration, distillation, floatation, foam separation, cooling, separation using gas layer, ground scattering, reverse osmosis and absorption.

In addition, methods for treating chemical wastewater are selectively used such as activated carbon adsorption, flocculation, precipitation, ion exchange, electrochemical treatment, electrodialysis, oxidation and reduction. Biological wastewater treatment methods include bacterial assimilation, algal extraction and nitrification-denitrification methods or denitrification-nitrification methods.

Nitrogen and phosphorus contained in sewage and wastewater belong to nutrient salts. If they can not be removed properly, they will become a main cause of eutrophication when they are discharged, causing abnormal propagation of algae in polluted waters, polluting water supply and industrial water. It is necessary to effectively remove nitrogen and phosphorus contained in the waste water and wastewater.

Conventional biological nitrogen and phosphorus removal methods include anaerobic / anoxic / aerobic (A2 / O), Bardenpho and UCT processes. Each of the above processes basically has at least one anaerobic tank, anoxic tank, and oxic tank, and is deformed in processes such as internal transportation and sludge transportation.

In recent years, MBR (Membrane Bioreactor) process combining biologic treatment and membrane has attracted attention in order to secure stable reuse. The MBR process can maintain the concentration of mixed microspores (MLSS: Mixed Liquor Suspended Solid) up to about 5000 to 1000 mg / L, which is advantageous in increasing the biological nitrogen removal performance.

In addition, in the prior art, an RO process using a reverse osmosis (RO) membrane module is added in addition to the MBR process described above to transfer the treated water from the biological treatment process by the MBR process to the RO membrane module, Dissolved organic matter contained in the water.

In such an RO process, ionic substances and dissolved organic substances are excluded, and the excluded substances are concentrated and discharged by about 4 to 5 times. In general, the concentrated water is treated with solids by removing the water using an evaporation method However, it is almost impossible to apply it because of high cost, and it is difficult to biological treatment because dissolved organic matter of RO concentrated water is a degradable organic matter.

The matters described in the background section are intended to enhance the understanding of the background of the invention and may include matters not previously known to those skilled in the art.

The embodiments of the present invention are directed to a system for treating waste water and wastewater which is capable of decomposing a refractory dissolved organic matter of RO-concentrated water into an organic matter that can be biologically treated by decomposing the dissolved organic matter into ozone, .

The waste water treatment system according to an embodiment of the present invention includes an MBR unit including an anaerobic tank, a stabilization tank, an anoxic tank, an oxic tank, and an immersion tank; An RO membrane module disposed at a downstream end of the MBR unit, for separating dissolved organic matter in the treated water treated by the MBR unit and discharging the concentrated water containing the dissolved organic matter; And an ozone reaction tank connected to the concentrated water discharge side of the RO membrane module and containing the concentrated water and injecting ozone by the concentrated water.

Further, in the waste water treatment system according to the embodiment of the present invention, in the ozone reaction tank, the refractory dissolved organic matter in the concentrated water can be decomposed into ozone and converted into an organic matter that can be biologically treated.

In addition, the wastewater treatment system according to an embodiment of the present invention includes: an ozone reaction tank, connected to the ozone reaction tank, floating and removing scum of the treated water flowing in the ozone reaction tank, And a scum floatation tank for supplying the scum floatation tank to the scum floatation tank.

Further, in the wastewater treatment system according to the embodiment of the present invention, the ozone reaction tank may be connected to the scum floating tank through the first connection line.

Further, in the wastewater treatment system according to the embodiment of the present invention, the scum floatation vessel may be connected to the anoxic tank of the MBR unit through the second connection line.

Further, in the wastewater treatment system according to the embodiment of the present invention, the scum floatation vessel is connected to the oxic tank of the MBR unit through a third connection line, and the ozone gas is supplied through the third connection line to the oxic tank .

Further, in the wastewater treatment system according to the embodiment of the present invention, the aerobic tank may be filled with a flocculant to remove dissolved phosphorus in the treated water flowing in the anoxic tank.

The anaerobic tank and the anaerobic tank may be connected to each other through a first transfer line and the activated sludge in the anaerobic tank may be transferred through the first transfer line to the anaerobic tank. have.

Also, in the wastewater treatment system according to the embodiment of the present invention, the submerged membrane separation tank and the stabilization tank are connected through the second conveyance line, and the activated sludge in the submerged separation membrane tank is connected through the second conveyance line And can be transported to the stabilizing tank.

The method for treating wastewater according to an embodiment of the present invention includes an MBR unit including an anaerobic tank, a stabilization tank, an anoxic tank, an oxic tank, and an immersion tank, and an RO membrane module disposed at a rear stage of the MBR unit Provides a wastewater treatment system; The raw water is sequentially introduced into the anaerobic tank, the stabilization tank, the anoxic tank, the aerobic tank and the immersion tank, and treated; Separating the dissolved organic matter in the treated water treated by the MBR unit from the RO membrane module and discharging the concentrated water containing the dissolved organic matter to the ozone reactor; Injecting ozone into the concentrated water in the ozone reaction tank, decomposing the refractory dissolved organic material in the concentrated water into ozone and converting it into an organism that can be biologically treated; And supplying the treated water in the ozone reaction tank to the scum floatation tank to float and remove scum from the treated water in the scum floatation tank.

Further, in the method for treating wastewater according to the embodiment of the present invention, treated water from which scum is removed from the scum floatation tank can be supplied to the anoxic tank.

Further, in the method of treating wastewater according to the embodiment of the present invention, it is possible to supply the ozone gas discharged from the scum floating tank to the oxic tank.

Further, in the method for treating wastewater and wastewater according to the embodiment of the present invention, the coagulant may be injected into the oxic tank.

Further, in the method for treating wastewater according to the embodiment of the present invention, the activated sludge in the anoxic tank may be returned to the anaerobic tank and the activated sludge in the dip tanks may be returned to the stabilization tank.

The embodiment of the present invention can simultaneously perform the bottom, wastewater and RO concentrated water treatment by applying the RO concentrated water ozone treatment and scum removal process to the MBR process and the RO process, so that the total facility cost and the operation cost can be reduced , And the convenience of the system operation can be improved.

These drawings are for the purpose of describing an embodiment of the present invention, and therefore the technical idea of the present invention should not be construed as being limited to the accompanying drawings.
1 is a block diagram schematically showing a waste water treatment system according to an embodiment of the present invention.
2 is a flow chart for explaining a process of a waste water treatment system according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, which will be readily apparent to those skilled in the art to which the present invention pertains. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

In order to clearly illustrate the present invention, parts not related to the description are omitted, and the same or similar components are denoted by the same reference numerals throughout the specification.

It is to be noted that the drawings are for reference only for the purpose of clearly and concretely explaining the preferred embodiments of the present invention and technical ideas or features, and therefore may be different from actual product specifications.

It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. .

In the following detailed description, the names of the components are denoted by the first, second, and so on in order to distinguish them from each other in terms of the same names, and are not necessarily limited to those in the following description.

Throughout the specification, when an element is referred to as "comprising ", it means that it can include other elements as well, without excluding other elements unless specifically stated otherwise.

It should be noted that terms such as " ... unit ", "unit of means "," part of item ", "absence of member ", and the like denote a unit of a comprehensive constitution having at least one function or operation it means.

1 is a block diagram schematically showing a waste water treatment system according to an embodiment of the present invention.

Referring to FIG. 1, the wastewater treatment system 100 according to the embodiment of the present invention can be applied to a water treatment apparatus for purifying drinking water, o / wastewater, industrial wastewater, and the like.

For example, the sewage / wastewater treatment system 100 is basically an activated sludge process in which the number of purification treatment targets (hereinafter referred to as "raw water" The phosphorus in the wastewater is consumed by dissolving the phosphorus and decomposing the organic matter in the sludge under the aerobic condition and consuming the phosphorus by the phenomenon that the phosphorus is excessively consumed and eventually discarding the excess sludge containing phosphorus. Removed.

The lower wastewater treatment system 100 includes an MBR unit 1 in which an anaerobic tank 10, a stabilization tank 20, an anoxic tank 30, an aerobic tank 40 and an immersion separation membrane tank 50 are sequentially installed .

In the anaerobic tank 10, the raw water to be treated flows into the raw water and the organic matter of the raw water is converted into volatile fatty acid, and the phophorus storage microorganism stores the organic matter as PHB (poly-β-hydroxybutyrate) The polyphosphate is converted into orthophosphate and released. As a result, the organic matter in the anaerobic tank 10 is decreased and phosphorus phosphate (PO4-P) is increased. At this time, the anaerobic tank 10 is connected to the anoxic tank 30 through the first transfer line Rl, and the activated sludge is transferred from the anoxic tank 30 to be treated.

The anoxic tank 30 removes nitrogen from wastewater by reducing nitrate nitrogen to nitrogen gas by using oxygen as a final electron acceptor in the NO3 molecule instead of free oxygen when the microorganisms decompose organic matter under anaerobic conditions.

The stabilization tank 20 is disposed between the anaerobic tank 10 and the anoxic tank 30 and is connected to the submerged membrane separation tank 50 through the second transfer line R2, Respectively.

The stabilization tank 20 uniformly mixes the transport sludge and supplies the organic matter from the raw water or the anaerobic tank 10 to efficiently reduce the dissolved oxygen in the transport sludge. In the submerged membrane separation tank 50, dissolved oxygen is high due to air blowing, so that the dissolved oxygen content in the transporting sludge is high. Accordingly, the concentration of dissolved oxygen is reduced through the stabilization tank 20, and the effect of dissolved oxygen in the anoxic tank 30 is blocked, thereby stably maintaining the denitrification efficiency.

In the oxic tank 40, denitrified raw water flows in the anoxic tank 30 to remove some organic substances from the aerobic condition, nitrification occurs, and a phosphorus process is performed in which excess phosphorus is absorbed in the raw water in the microorganism body.

The submerged membrane separation tank (50) is subjected to solid-liquid separation through the submerged hollow fiber membrane (51) with sludge-containing solid matter and treated water. Finally, phosphorus-containing excess sludge is discharged from the submerged membrane separation tank 50 to remove phosphorus. Also, the sludge is conveyed to the stabilization tank 20 for maintaining the concentration of microorganisms in each reaction tank.

The respective reaction vessels of the anaerobic tank 10, the stabilization tank 20, the anoxic tank 30, the aerobic tank 40, and the submerged membrane separation tank 50 may communicate with each other through a pipeline or the like.

The bottom and wastewater treatment system 100 according to the embodiment of the present invention includes a reverse osmosis (RO) membrane module for separating dissolved organic substances and the like in the treated water treated by the biological treatment process by the MBR unit 1, (3).

Here, the reverse osmosis (RO) membrane module 3 is configured to be connected to the downstream end of the MBR unit 1, to remove ionic substances and dissolved organic substances contained in the treated water, (Hereinafter referred to as " concentrated water " for convenience) and discharges the recycled water from which the ionic substance and dissolved organic matter have been removed.

Since the specific configuration of the reverse osmosis (RO) membrane module 3 is well known in the art, a detailed description of the configuration thereof will be omitted herein.

The bottom and wastewater treatment system 100 according to the embodiment of the present invention which constitutes the MBR unit 1 and the RO membrane module 3 has the same structure as that of the RO membrane module 3, Decomposable dissolved organic matter of the discharged concentrated water can be decomposed into ozone and converted into an organic matter that can be biologically treated.

To this end, the wastewater treatment system 100 according to the embodiment of the present invention further includes an ozone reaction tank 60 and a scum floating tank 70.

In the embodiment of the present invention, the ozone reaction tank 60 is connected to the concentrated water discharge side of the reverse osmosis (RO) membrane module 3 (hereinafter referred to as "RO membrane module" for convenience) (3), and the ozone is injected into the concentrated water.

The ozone reaction tank 60 is connected to the RO membrane module 3 through a concentrated water discharge line 5 and an ozone generator 61 for injecting ozone as concentrated water is installed in the ozone reaction tank 60 .

In the ozone reaction tank 60, the ozone is introduced into the concentrated water through the ozone generator 61, whereby the refractory dissolved organic matter in the concentrated water can be decomposed into ozone and converted into an organic matter that can be biologically treated.

The scum floatation tank 70 floats the scum of the treated water flowing in the ozone reaction tank 60 and removes the scum from the ozone reaction tank 60 through the first connection line 71, Can be connected.

The scum floatation tank 70 may be connected to the anoxic tank 30 through the second connection line 72 to supply the treated water from which the scum has been removed to the anoxic tank 30 of the MBR unit 1.

That is, the scum floatation tank 70 supplies the dissolved organic matter, which has been decomposed by ozone in the ozone reaction tank 60 to be biologically processable organic matter, to the anoxic tank 30 together with the treated water through the second connection line 72 .

The dissolved organic matter, which is converted into an organic matter decomposed by ozone and decomposed into ozone as described above, is put into the anoxic tank 30 to utilize dissolved organic matter decomposed by ozone as an organic material source for denitrification in the anoxic tank 30 .

The scum floatation tank 70 may be connected to the oxic tank 40 through a third connection line 73 to supply the ozone gas collected at the upper end thereof to the oxic tank 40 of the MBR unit 1.

The reason why the ozone gas generated in the scum floating tank 70 is supplied to the oxic tank 40 is to increase the oxidizing power for decomposing the organic matter in the raw water in the oxic tank 40 as the ozone gas.

Meanwhile, in the aerobic tank 40, a flocculant for reacting and coagulating with the phosphorus component is injected to remove dissolved phosphorus in the treated water flowing in the anoxic tank 30.

Hereinafter, a method for treating wastewater and wastewater using the wastewater treatment system 100 according to an embodiment of the present invention will be described in detail with reference to FIG.

2 is a flow chart for explaining a process of a waste water treatment system according to an embodiment of the present invention.

1 and 2, in the embodiment of the present invention, raw water such as bottom / wastewater is introduced into the anaerobic tank 10, the stabilization tank 20, the anoxic tank 30, the aerobic tank 40, Is sequentially introduced into the submerged membrane separation tank (50) and a membrane-biological treatment process is performed (S11).

Then, in the embodiment of the present invention, the treated water after the membrane-biological treatment process of the MBR unit 1 is supplied to the RO membrane module 3. The RO membrane module 3 separates the dissolved organic substances in the treated water treated by the MBR unit 1 and discharges the concentrated water containing the dissolved organic substances to the ozone reaction tank 60 (S12).

In the ozone reaction tank 60, the ozone is introduced into the concentrated water through the ozone generator 61 to decompose the refractory dissolved organic matter in the concentrated water into ozone to convert into organic matter that can be biologically treated (S13).

Next, in the embodiment of the present invention, the ozone-treated water in the ozone reaction tank 60 is supplied to the scum floating tank 70 through the first connection line 71. Then, in the scum floatation tank 70, the scum of the treated water floats and the scum is removed (S14).

Next, in the embodiment of the present invention, the treated water from which the scum is removed from the scum floating tank 70 is supplied to the anoxic tank 30 of the MBR unit 1 through the second connection line 72 (S15). That is, the scum floatation tank 70 supplies the dissolved organic matter, which has been decomposed by ozone in the ozone reaction tank 60 to be biologically processable organic matter, to the anoxic tank 30 together with the treated water through the second connection line 72 do.

Therefore, in the embodiment of the present invention, the dissolved organic matter decomposed by ozone in the ozone reaction tank 60 is supplied to the anoxic tank 30 through the scum floating tank 70 so that the dissolved organic matter is removed from the organic It can be used as a material source.

In this case, when the nitrate nitrogen included in the concentrated water in the embodiment of the present invention is denitrified in the anoxic tank 30, the source of the deficient organic material in the anoxic tank 30 can be supplied from the outside. In the embodiment of the present invention, the activated sludge in the anoxic tank 30 can be transported to the anaerobic tank 10 through the first transport line Rl (S16).

During the above process, in the embodiment of the present invention, the ozone gas collected at the upper end of the scum floating tank 70 is supplied to the oxic tank 40 of the third connection line 73 (S17). Accordingly, in the embodiment of the present invention, the ozone gas generated from the scum floatation tank 70 is supplied to the oxic tank 40, so that the oxidation power for decomposing the organic matter in the oxic tank 40 can be increased as the ozone gas.

Meanwhile, in the embodiment of the present invention, the coagulant may be injected into the aerobic tank 40 to aggregate and remove dissolved phosphorus in the treated water flowing in the anoxic tank 30 (S18). In the embodiment of the present invention, the activated sludge in the submerged membrane separation tank 50 can be conveyed to the stabilization tank 20 through the second conveyance line R 2 during the above-described process.

According to the wastewater treatment system 100 according to the embodiment of the present invention that treats raw water through a series of processes as described so far, the MBR unit 1 and the RO membrane module 3, Decomposable dissolved organic matter of the RO concentrated water discharged from the module 3 is decomposed into ozone in the ozone reaction tank 60 to be converted into an organic material that can be biologically treated and the MBR unit 70 is removed from the scum floating tank 70, To the anoxic tank (30) of the anoxic tank (1) and utilized as an organic material source for denitrification in the anoxic tank (30).

Therefore, in the embodiment of the present invention, since the RO concentrated water is subjected to the ozone treatment and the scum removal process in the MBR process and the RO process, it is possible to simultaneously perform the bottom, wastewater and RO concentrated water treatment, And the convenience of the system operation can be improved.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, Other embodiments may easily be suggested by adding, changing, deleting, adding, or the like of elements, but this also falls within the scope of the present invention.

One… MBR unit 3 ... RO membrane module
5 ... Concentrated water discharge line 10 ... Anaerobic
20 ... Stabilization tank 30 ... Anoxic tank
40 ... Fishing vessel 50 ... The submerged membrane separation tank
60 ... Ozone Reactor 61 ... Ozone generator
70 ... Scum float ho ... The first connection line
72 ... The second connection line 73 ... The third connecting line
R1 ... The first conveying line R2 ... The second conveying line

Claims (13)

An MBR unit including an anaerobic tank, an anaerobic tank, an anaerobic tank, an aerobic tank, and an immersion tank;
An RO membrane module disposed at a downstream end of the MBR unit, for separating dissolved organic matter in the treated water treated by the MBR unit and discharging the concentrated water containing the dissolved organic matter; And
An ozone reaction tank connected to the concentrated water discharge side of the RO membrane module and containing the concentrated water and injecting ozone by the concentrated water,
And a waste water treatment system. The method according to claim 1,
Wherein the ozone reaction tank decomposes the refractory dissolved organic material in the concentrated water into ozone and converts it into an organic material that can be biologically treated. The method according to claim 1,
And a scum floating tank connected to the ozone reaction tank for floating and removing scum from the treated water flowing in the ozone reaction tank and supplying the treated water to the MBR unit. The method of claim 3,
Wherein the ozone reaction tank is connected to the scum floating body through a first connection line,
Wherein the scum floatation vessel is connected to the anoxic tank of the MBR unit through a second connection line. 5. The method of claim 4,
Wherein the scum floatation vessel is connected to the oxic tank of the MBR unit through a third connection line and supplies ozone gas to the oxic tank through the third connection line. 6. The method of claim 5,
Wherein the aerobic tank is charged with a flocculant to remove dissolved phosphorus in the treated water flowing in the anoxic tank. 5. The method of claim 4,
Wherein the anoxic tank and the anaerobic tank are connected through a first conveyance line and the activated sludge in the anoxic tank is conveyed to the anaerobic tank through the first conveyance line. 8. The method of claim 7,
Wherein the submerged membrane separation tank and the stabilization tank are connected through a second conveyance line and the activated sludge in the submerged separation membrane tank is conveyed to the stabilization tank through the second conveyance line. An underground wastewater treatment system as set forth in claim 1, comprising an MBR unit including an anaerobic tank, a stabilization tank, an anoxic tank, an oxic tank and an immersion tank, and an RO membrane module disposed at a rear stage of the MBR unit;
The raw water is sequentially introduced into the anaerobic tank, the stabilization tank, the anoxic tank, the aerobic tank and the immersion tank, and treated;
Separating the dissolved organic matter in the treated water treated by the MBR unit from the RO membrane module and discharging the concentrated water containing the dissolved organic matter to the ozone reactor;
Injecting ozone into the concentrated water in the ozone reaction tank, decomposing the refractory dissolved organic material in the concentrated water into ozone and converting it into an organism that can be biologically treated;
Supplying the treated water in the ozone reaction tank to the scum floatation tank, and floating and removing scum from the treated water in the scum floatation tank. 10. The method of claim 9,
And supplying the treated water from which the scum is removed from the scum floating tank to the anoxic tank. 10. The method of claim 9,
And the ozone gas discharged from the scum floatation tank is supplied to the oxic tank. 12. The method of claim 11,
And a flocculant is added to the aerobic tank. 11. The method of claim 10,
Transporting the activated sludge in the anoxic tank to the anaerobic tank, and transferring the activated sludge in the submerged membrane separation tank to the stabilization tank.

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