KR101748778B1 - Multi-level eco-friendly sewage treatment system - Google Patents

Abstract

The present invention relates to a multistage environmentally friendly wastewater treatment system, and more particularly, to a multistage environmentally friendly wastewater treatment system that performs filtration through a filter material in a state in which a metal contained in discharged water of a sewage treatment plant, To a multi-step eco-friendly wastewater treatment system that enhances filtration efficiency and further enhances phosphorus (P) removal function.

Description

[0001] Multi-level eco-friendly sewage treatment system [

The present invention relates to a multistage environmentally friendly wastewater treatment system in the sewage technology field, and more particularly to a multistage environmentally friendly wastewater treatment system, which comprises filtration through a filter medium in a state in which a metal contained in discharged water of a sewage treatment plant, (P) removal function by enhancing the filtration efficiency and performing the functions of the sewage treatment system.

In general, phosphorus (phosphoric acid), which is the main cause of eutrophication and is a limiting substance of algae growth, has been mainly used in biological treatment methods and chemical treatment methods using coagulant in the total phosphorus treatment apparatus of sewage treatment plants.

However, biological processes are difficult to operate, and it is not easy to obtain sustained and stable effluent quality.

Other chemical methods are relatively easy to operate but suffer from drug costs and sludge disposal problems.

Another electrolytic / flocculent phosphorus removal technology is one of the technologies that can take advantage of the chemical removal technology and solve the disadvantages of the chemical precipitation method, but it has problems such as electrode corrosion.

The reuse of shell is used for removal of exhaust gas, improvement of acid soil, adsorption of heavy metals, high concentration of phosphorus, etc. However, calcium carbonate, which occupies most of the oyster shell, has a large amount of sludge generated in water treatment and contains a large amount of organic and inorganic matters Due to the problem, there is a problem after proper baking process.

In addition, the crystallization dephosphorization method is one of physico-chemical treatment methods that have been put to practical use among methods of removing phosphorus in sewage, but it is possible to treat ordinary sewage secondary treatment water, The removal performance differs depending on the set pH, the calcium concentration, the water temperature, the interfering substances in the raw water, the contact time, the performance of the contact material, and the phosphorus acid to be removed is soluble phosphoric acid. Therefore, phosphorus, polyphosphoric acid, ) Should be removed by secondary functions such as filtration.

In the method of removing dehydration, magnesium is added to sewage to adjust the pH of the sewage, thereby recovering phosphorus as a crystal of magnesium ammonium phosphate (MAP). However, it is not suitable for treating discharged water.

In particular, the biological removal process of anaerobic and aerobic biomass which is widely used is called as polyphosphoric acid, which is the cellular material of phosphorus microorganisms. Since organic matter such as volatile fatty acid should be supplied, It is difficult to improve the biological phosphorus and nitrogen simultaneous process in reality because it compete with the organic matter demand for removal.

In addition, conventional physical and chemical treatment apparatuses have difficulties in overuse of chemicals and disposal of sludge treatment.

In addition, the discharged water often contains a large amount of iron, and since it has been filtered immediately without removing it, the life of the filter medium is shortened and the recycling of the recovered iron is also disadvantageous.

Korea Patent Registration No. 10-0861554 (Sep. 26, 2008) 'Filtration and adsorption multi-stage wastewater treatment device for removing total phosphorus from sewage treatment plant effluent water'

SUMMARY OF THE INVENTION Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and an object of the present invention is to provide a method of manufacturing a sewage treatment plant, The present invention provides a multistage environmentally friendly wastewater treatment system that enhances filtration efficiency and removes phosphorus (P) by performing filtration through a filtration system.

In order to achieve the above object, according to the present invention, there is provided a flow rate control apparatus comprising: a flow rate control unit for controlling a residence time of a discharge water discharged from a sewage treatment plant in accordance with a flow rate, a suspended substance, An upflow type pre-filtration unit 20 composed of a synthetic resin filter material to which a predetermined amount of flow is supplied from the flow control unit 10; A filtration / adsorption unit 30 which flows into the lower end of the pre-filtration unit 20 and then flows through the upper end of the pre-filtration unit 20; A blower 40 for desorbing the material adsorbed to the filter media by using air and treatment water when cleaning the pre-filtration unit 20 and the filtration and absorption unit 30; And a disinfecting tank 50 for passing the discharged water through the flow control unit 10, the pre-filtration unit 20, and the filtration and absorption unit 30 in three stages, and disinfecting pathogenic bacteria in the discharged water. A sewage treatment system comprising:
The metal separator (1) comprises a main body housing (100) in the shape of a rectangular box with an open upper part; A controller 130 installed on a front side of the main body housing 100; First and second dams 150 and 152 protruding from the bottom surface of the main body housing 100 at a predetermined height and partitioning the inside into a left chamber CH1, a center chamber CH2 and a right chamber CH3; First and second cylindrical cylindrical first and second water tanks 300 and 310 provided on the bottom surfaces of the left chamber CH1 and the right chamber CH3, respectively; An inlet 110 installed on a front surface of the main body housing 100 to supply discharged water to each of the first and second water tanks and controlled by the controller 130 to be opened and closed; A discharge port 120 provided on the rear surface of the main body housing 100 in the direction opposite to the charging port 110 and communicating with the left and right chambers CH1 and CH3 and controlled by the controller 130; A drain hole 410 formed at the center of the width of the center chamber CH2 and capable of being discharged to the outside of the main body housing 100; A pair of swash plates 400 installed at both sides of the drain hole 410 and fixed to the first and second dams 150 and 152, respectively; A ball screw (200) installed to be rotatable across the short side of the upper end of the main body housing (100); A driving motor 210 connected to one end of the ball screw 200 and controlled by the controller 130; First and second screw blocks SB1 and SB2 screwed to the ball screw 200 by a distance corresponding to a center distance between the left chamber CH1 and the center chamber CH2; A guide bar 250 installed parallel to the ball screw 200; A pair of first and second bar blocks (BB1 and BB2) slidably fitted in the guide bar (250); First and second connecting blocks CT1 and CT2 connecting the first and second bar blocks BB1 and BB2 with the first and second screw blocks SB1 and SB2; First and second cylinders 260 and 270 fixed to a central lower surface of the first and second connection blocks CT1 and CT2 and controlled by the controller 130; And first and second forks (264 and 274) in a lattice shape coupled to the cylinder rods of the first and second cylinders (260 and 270) and electromagnetized under the control of the controller (130), the bottom surface of the main body housing And a discharge solenoid valve SOL controlled to be opened and closed by the controller 130 is installed at a predetermined position in a circumferential direction with respect to the inner bottom surface of the first and second water tanks 300 and 310 Wherein the sewage treatment plant is a sewage treatment plant.

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According to the present invention, the filtering function is performed through the filter material in a state in which the metal contained in the discharged water of the sewage treatment plant, particularly the magnetic metal, is previously separated and removed, thereby improving the filtration efficiency and enhancing the phosphorus removal function .

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is an overall configuration diagram of a system according to the invention;
2 is an exemplary photograph showing the essential part of the system according to the present invention;
3 is a view showing an example of a synthetic resin filter medium (A) and an adsorbent filter material (B) in a pre-filter unit constituting the system according to the present invention.
FIG. 4 is a graph showing the test result of the effect of extending the filtration duration of the pre-filtration unit of the system according to the present invention.
FIG. 5 is a graph showing the filtration treatment result of the phosphorus adsorption medium in the system according to the present invention, in comparison with the phosphorus removal test. FIG.
6 is a graph showing the total removal results of the system according to the present invention.
7 is an exemplary view of a metal separator constituting a system according to the present invention;
Fig. 8 is an exemplary view showing the front and back sides of Fig. 7; Fig.
9 is an enlarged view of the main part of Fig.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Before describing the present invention, the following specific structural or functional descriptions are merely illustrative for the purpose of describing an embodiment according to the concept of the present invention, and embodiments according to the concept of the present invention may be embodied in various forms, And should not be construed as limited to the embodiments described herein.

In addition, since the embodiments according to the concept of the present invention can make various changes and have various forms, specific embodiments are illustrated in the drawings and described in detail herein. However, it should be understood that the embodiments according to the concept of the present invention are not intended to limit the present invention to specific modes of operation, but include all modifications, equivalents and alternatives falling within the spirit and scope of the present invention.

The present invention is characterized in that most of the structure of the above-mentioned Patent No. 10-0861554 is utilized as it is, and means for previously separating and removing iron powder contained in the discharged water is further provided. Therefore, the preprocessing means will be described again with reference to FIGS. 7-9, and FIGS. 1 to 6 cite the registered patent as it is.

As shown in FIGS. 1 and 2, in the system according to the present invention, the discharged water is discharged from the secondary settler and flows into the flow control unit 10, and the residence time is adjusted according to the flow rate of the discharged water, suspended substances and total phosphorus.

Here, the secondary settling water is subjected to a process of storing the treated water for a predetermined time or flowing at a low flow rate in a water treatment facility such as a water purification plant or a sewage treatment plant to precipitate solid contaminants generated during the treatment process. The sedimentation pond is called a sedimentation pond and the fluid mixture of solid contaminants is called a sludge or sludge.

The first settling basin serves as a pretreatment for the first treatment and the biological treatment. The second settling basin is a sludge generated by the biological treatment, And the process water.

After the residence time is adjusted by the flow rate regulator 10, the flow rate regulator 10 flows a predetermined amount of the flow rate into the upflow type prefilter 20.

The pre-filter unit 20 is made of a synthetic resin filter material.

At this time, the synthetic resin filter material in the pre-filtration unit 20 uses a polyurethane-based material to filter suspended solids and colloid materials.

In addition, the discharged water flowing into the pre-filtration unit 20 flows into the lower end portion and passes through the lower end portion and the upper end portion of the pre-filtration unit 20.

Next, the discharged water passing through the pre-filtration unit 20 flows into the filtration and absorption unit 30.

At this time, the discharged water flowing in the upflow direction from the pre-filtration unit 20 flows into the filtration and absorption unit 30 again in the upward flow.

The filtration and adsorption unit 30 removes the total suspended solids by filtrating fine suspended matters and recovers the dissolved phosphorus in the form of ion exchange using a phosphorus adsorbent as a filter medium. It is used in the filtration and absorption unit 30 The particulate zirconium-based adsorbent having a diameter of about 0.7 mm is used as the adsorbent.

In addition, the cleaning of the pre-filtration unit 20 proceeds in a manner that the material adsorbed to the filter material is desorbed by the blower using air and treated water.

The discharged water flows to the disinfecting tank 50 after the three-stage treatment through the flow control unit 10, the pre-filtration unit 20, and the filtration and absorption unit 30, and disinfects pathogenic bacteria in the discharged water .

This is to treat the effluent of the sewage treatment plant through a multi-stage tank.

That is, the discharged water is discharged from the secondary settler, flows into the flow rate regulator 10, and is supplied to the pre-filtration unit 20 composed of a synthetic resin filter medium at a proper flow rate to the system.

If the residence time is to be adjusted according to the flow rate, the suspended substance and the total phosphorus of the introduced effluent, the flow rate regulator 10 is required.

The inflow water flows into the lower end of the pre-filtration unit 20, passes through the lower end and upper end of the pre-filtration unit 20, and then flows into the filtration and absorption unit 30.

Here, the filtration and adsorption apparatuses for treating sewage treatment plant effluent are composed of two stages of filter media inside the apparatus. The front filtration apparatus unit 20 is filtered by a polyurethane-based synthetic resin filter material, The adsorption unit 30 is operated in an upward flow by using an adsorbent having a particle size of about 0.7 mm.

In addition, when used as a tertiary treatment in a sewage treatment plant, it flows into the disinfecting tank 50 to disinfect pathogenic bacteria such as Escherichia coli.

The suspended filtrate of the discharged water can be treated through the filtration apparatus.

As shown in FIG. 3, the pre-filtration unit 20 is a filtration unit filled with an environmentally suitable fibrous resin or a sponge-like resin material.

At this time, when the pre-filtration unit 20 is cleaned, the blower 40 is operated to remove the substances adsorbed to the filter material by using air and treated water, thereby eliminating clogging.

In addition, as shown in FIG. 4, the filtration duration when the filtration / adsorption device unit 30 is directly used and the total filtration unit 20 is used is shown in the present invention. In the case of direct filtration, But if the pre-filtration system is used in the pre-filtration unit 20, the filtration can last for 5 to 10 days without clogging.

Therefore, by using the pre-filtration unit 20, the filtration duration is longer than that when the phosphorus-adsorbed filter material is used alone, the loss due to filtration device clogging is small, and the function recovery by backwashing is easy.

In the filtration apparatus according to the present invention, the filtration and adsorption unit 30 is a unit for filtrating fine suspension and adsorbing and recovering phosphorus on the adsorption medium, and the filter medium is filled with a filter material suitable for adsorption / recovery of phosphorus.

In addition, as shown in FIG. 5, in order to select and evaluate the filter media in the filtration and adsorption unit 30 of the system of the present invention, after the reaction through the isothermal adsorption experiment on the existing adsorbent and the ion exchange resin, As a result of analyzing the same concentration by the filtration adsorption apparatus, it was found that the adsorption amount of the lower adsorbent (layered double oxide: LDH), zirconium oxide and zirconium ferrite, styrene type strong basic anion exchange Comparing and testing the phosphorus removal function of resins and flocculants, materials such as phosphorus adsorption media, such as bottom sedimentation system and zirconium adsorbent, showed considerably better performance than conventional media.

Also, as shown in FIG. 6, as a result of the pilot scale test in the sewage treatment plant, the apparatus uses a synthetic filter medium to remove the large solid matter from the pre-filtration unit 20 at the front end as shown in FIG. 1, And a filtration / adsorption device unit 30 to be adsorbed.

The filter material used in this field test was made of polyurethane material at the front end, and a particulate zirconium-based adsorbent having a diameter of about 0.7 mm was used as the phosphorus adsorbent. As a result, suspended solids (SS) was introduced into the sewage treatment plant at 10 ~ 200 mg / L depending on the sedimentation conditions.

The influent concentration of total phosphorus (T-P) was 0.5-5 mg / L. The treated water was less than 5 mg / L for the normal inflow water and less than 10 mg / L for the high influx. In this case, the total phosphorus was less than 1 mg / L in all cases, and the soluble phosphorus was 0.1 mg / L or less. FIG. 5 shows that even if there is a change in the total number of persons who are introduced, the total number of people is removed with stability.

As described above, the present invention is a system for removing and recovering total phosphorus and dissolved phosphorus by using a phosphorus adsorption medium combined with a filtration process in the main stream of the lower treatment effluent to improve the quality of the sewage, ㆍ It is equipped with adsorption wastewater treatment function.

In addition, the present invention is characterized in that the flow control unit 10 is provided with the above-described structure while passing the metal separator 1 (see FIG. 7) before the discharged water discharged from the secondary clarifier is transferred to the flow rate control unit 10, So that the magnetic metal contained in the discharged water, especially the iron powder, is discharged in a completely removed state.

Such a metal separator 1 includes a main body housing 100, as shown in Figs.

At this time, the main body housing 100 is formed in a rectangular box shape having an open interior and an open top. A pair of inlet ports 110 are formed on both sides of the front surface as shown in FIG. 8A, And a pair of outlets 120 are formed on both sides of the rear side as shown in FIG. 8 (b).

A controller 130 for control is installed on a part of the upper surface of the main body housing 100. The discharged water having the magnetic metal components separated and removed through the discharge port 120 on the rear side of the main body housing 100 And is designed to be transferred to the flow amount bending portion 10.

In addition, although not shown, the charging port 110 includes a solenoid valve that is controlled by the controller 130 so that only a predetermined amount of discharged water can be supplied through the two charging ports 110 alternately.

The first and second dams 150 and 152 are installed inside the main body housing 100 to divide the internal space into three chambers into a left chamber CH1, a center chamber CH2 and a right chamber CH3.

The first and second dams 150 and 152 may be installed at a height of less than a half of the height of the main body housing 100, ) Can be secured.

7 (a), which is a perspective view of the main housing 100, FIG. 7 (a) is a plan view of the main housing 100, And a drive motor 210 is connected to one end of the ball screw 200. The drive motor 210 is fixed to one side of the main body housing 100, do.

The guide bar 250 is provided in parallel with the ball screw 200 in the same manner.

The first screw block SB1 and the first bar block BB1 are provided on the ball screw 200 and the guide bar 250. The first screw block SB1 includes a ball screw And the first bar block BB1 is configured to be slidably engaged with the guide bar 250 while being screwed to the guide bar 200 and moved to the left or right along the rotation direction of the ball screw 200 when the ball screw 200 rotates. .

In addition, the first screw block SB1 and the first bar block BB1 are connected to each other by the first linkage CT1. The first screw block SB1 and the first bar block BB1 are connected to each other through the second screw block SB2, CT2) - second bar block (BB2).

The first cylinder 260 is vertically fixed to the first connecting rod CT1 and the second cylinder 270 is vertically fixed to the second connecting rod CT2. The first fork 264 in the form of a lattice is integrally formed in the cylinder rod 262 and the second fork 274 in the form of a lattice is formed integrally with the second cylinder rod 272 of the second cylinder 270 do.

In this case, the first and second forks 264 and 274 should be sealed electromagnets, the control may be performed by the controller 130, and the wiring may be carried by the first and second cylinder rods 262 and 272.

7 (b), the first fork 264 is positioned in the left chamber CH1 and the second fork 274 is positioned in the center chamber CH2. ≪ / RTI >

The operation of the first and second cylinders 260 and 270 is controlled by the controller 130 in sequence.

On the other hand, the first and second water tanks 300 and 310 as shown in FIGS. 7C and 9A are installed on the bottom surfaces of the left chamber CH1 and the right chamber CH3.

In this case, the first and second water tanks 300 and 310 are formed in a cylindrical shape with an open upper surface having a space therein, and the cylinder height of the first and second water tanks 300 and 310 is the same as that of the first and second dams 150 and 152 It is preferable to maintain the height.

The inlet 110 is disposed at a position higher than the upper end of the first and second water tanks 300 and 310 so that when the discharged water flows in the inlet 110, Respectively.

In this case, the piping end of the inlet 110 should be designed to avoid an interference with the first and second forks 264 and 274, respectively.

A discharge solenoid valve SOL is installed at a portion of the cylindrical bottom of the first and second water tanks 300 and 310 and a horizontal line of the cylinder. The discharge solenoid valve SOL is opened and closed by a controller 130.

The bottom surface of each of the left chamber CH1 and the right chamber CH3 of the main body housing 100 is formed to be inclined toward the discharge port 120, do. The discharge port 120 is located at the lower portion of the rear wall of the left chamber CH1 and the lower portion of the rear wall of the right chamber CH3 formed by partitioning the inner hollow space of the main body housing 100, And can be discharged to the outside of the main body housing 100 through the discharge port 120.

7 and 9B, the center chamber CH2 is provided with a pair of swash plates 400 inclined toward the drain hole 410 formed at the center of the width, and the swash plate 400 A pair of sweepers 420 arranged in the width direction are provided on the side fixed to the first and second dams 150 and 152. The sweep fingers 420 are arranged such that a spring 470 Is bound on the flow block (440) by a connecting bar (460).

At this time, the connecting bar 460 is composed of two divided parts, and the two parts separated by the spring 470 are combined to form a single member. Therefore, it is possible to adjust the length by elasticity.

One end of the screw shaft 430 is fixed to the second dam 152 so as to be rotatable about its axis and the screw shaft 430 is fixed to the other end of the swash plate 400 by a screw drive And a screw drive motor 450 is fixed to the first dam 150 and is driven and controlled by the controller 130. [

In addition, the flow block 440 is screwed to the screw shaft 430 and is configured to be movable in either the left or right direction along the rotational direction when the screw shaft 430 rotates.

When the magnetic metal component remains on the inclined surface of the swash plate 400 during the movement of the first and second forks 264 and 274, the sweepper 420 moves and sweeps the sweep purge with the drain hole 410, The collected components are processed separately.

The present invention having such a configuration has the following operational relationship.

First, a predetermined amount of the discharged water is introduced into the first and second cylindrical water tanks 300 and 310 provided in the left chamber CH1 and the right chamber CH3 through the inlet 110, respectively. In this case, they may be supplied to both sides at the same time, or they may be sequentially inputted according to the sequence control.

When the discharge signal is applied to the first and second cylinders 260 and 270 according to the control signal of the controller 130, the first and second cylinder rods 262 and 272 are lowered and the first fork 264 Descends until it is held at a gap as if it touches the bottom surface of the cylindrical first tank 300.

Of course, the second fork 274 must descend in the central chamber CH2 until it reaches the highest point of the inclined plane of the swash plate 400 until it is maintained at a gentle interval.

The lowering control of the first and second forks 264 and 274 is performed separately and can be set and controlled in a programmable manner according to the position of each fork. So that the falling distance is controlled in accordance with the detection signal of the sensor.

The first and second forks 264 and 264 are moved to the right so that the first fork 264 is located in the center chamber CH2 and the second fork 274 is located in the second tank 273 of the right chamber CH3. 310, the second fork 274 descends deeper and the first fork 264 falls relatively less.

On the other hand, since electricity is applied to the first and second forks 264 and 274 at the completion of the descent, the magnetic metal components included in the discharged water instantaneously attach to the first fork 264.

On the other hand, since the second fork 274 is lifted and lowered in the central chamber CH2, the magnetic metal component attached to the second fork 274 must be removed rather than the magnetic metal component is attracted by the electromagnet. Control.

This is because the first and second forks 264 and 274 repeatedly perform the magnetic metal component adsorption and magnetic metal component separating operation while reciprocating back and forth through the first tank-center chamber-second tank, 274 are moved to the center chamber CH2 in a state where the magnetic metal components are adsorbed at the second water tank 310 side.

When the magnetic metal component adsorption and separation operations are completed for a predetermined time, the first and second forks 264 and 274 are lifted and then moved in accordance with the driving of the driving motor 210.

In this case, the ascending height of the first and second forks 264 and 274 must be higher than the first and second dams 150 and 152 naturally.

Then, the second fork 274 is placed on the right chamber CH3, and the first fork 264 is placed on the center chamber CH2.

This is because the ball screws 200 are rotated in accordance with the rotation of the driving motor 210 and the first and second screw blocks SB1 and SB2 move along with the first and second connecting blocks CT1 and CT2, And the first and second cylinders 260 and 270 move together, the first and second forks 264 and 274 can move naturally.

Then, the first and second forks 264 and 274 descend in the center chamber CH2 and the right chamber CH3, respectively, and perform the same operations as those described above.

The magnetic metal component that has fallen from the center chamber CH2 flows along the inclined surface of the swash plate 400 and is discharged to the drain port 410.

In addition, the magnetic metal component remaining on the swash plate 400 is swept by the sweepper 420.

10: Flow control unit 20: Front filtration unit
30: Filtration / adsorption device unit 40: Blower
50: Disinfection Grandmother

Claims (1)

A flow control unit 10 for controlling the residence time of the effluent discharged from the sewage treatment plant through the second settling basin according to the flow rate, suspended solids and total phosphorus of the effluent; An upflow type pre-filtration unit 20 composed of a synthetic resin filter material to which a predetermined amount of flow is supplied from the flow control unit 10; A filtration / adsorption unit 30 which flows into the lower end of the pre-filtration unit 20 and then flows through the upper end of the pre-filtration unit 20; A blower 40 for desorbing the material adsorbed to the filter media by using air and treatment water when cleaning the pre-filtration unit 20 and the filtration and absorption unit 30; And a disinfecting tank 50 for passing the discharged water through the flow control unit 10, the pre-filtration unit 20, and the filtration and absorption unit 30 in three stages, and disinfecting pathogenic bacteria in the discharged water. A sewage treatment system comprising:
The metal separator (1) comprises a main body housing (100) in the shape of a rectangular box with an open upper part; A controller 130 installed on a front side of the main body housing 100; First and second dams 150 and 152 protruding from the bottom surface of the main body housing 100 at a predetermined height and partitioning the inside into a left chamber CH1, a center chamber CH2 and a right chamber CH3; First and second cylindrical cylindrical first and second water tanks 300 and 310 provided on the bottom surfaces of the left chamber CH1 and the right chamber CH3, respectively; An inlet 110 installed on a front surface of the main body housing 100 to supply discharged water to each of the first and second water tanks and controlled by the controller 130 to be opened and closed; A discharge port 120 provided on the rear surface of the main body housing 100 in the direction opposite to the charging port 110 and communicating with the left and right chambers CH1 and CH3 and controlled by the controller 130; A drain hole 410 formed at the center of the width of the center chamber CH2 and capable of being discharged to the outside of the main body housing 100; A pair of swash plates 400 installed at both sides of the drain hole 410 and fixed to the first and second dams 150 and 152, respectively; A ball screw (200) installed to be rotatable across the short side of the upper end of the main body housing (100); A driving motor 210 connected to one end of the ball screw 200 and controlled by the controller 130; First and second screw blocks SB1 and SB2 screwed to the ball screw 200 by a distance corresponding to a center distance between the left chamber CH1 and the center chamber CH2; A guide bar 250 installed parallel to the ball screw 200; A pair of first and second bar blocks (BB1 and BB2) slidably fitted in the guide bar (250); First and second connecting blocks CT1 and CT2 connecting the first and second bar blocks BB1 and BB2 with the first and second screw blocks SB1 and SB2; First and second cylinders 260 and 270 fixed to a central lower surface of the first and second connection blocks CT1 and CT2 and controlled by the controller 130; And first and second forks (264 and 274) in a lattice shape coupled to the cylinder rods of the first and second cylinders (260 and 270) and electromagnetized under the control of the controller (130), the bottom surface of the main body housing And a discharge solenoid valve SOL controlled to be opened and closed by the controller 130 is installed at a predetermined position in a circumferential direction with respect to the inner bottom surface of the first and second water tanks 300 and 310 Wherein the sewage treatment system is a multi-stage sewage treatment system.

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