KR100481821B1 - Process and plant for wastewater treatment - Google Patents

Abstract

A water treatment apparatus capable of gas induction and sludge separation is disclosed. Such a water treatment device has a reaction tank having a means for generating air by supplying air to the waste water, and the waste water and bubbles introduced by dividing the inside of the reaction tank into multiple stages up and down in density order. Sludge separation means for decomposing contaminants by moving and increasing the contact area between the waste water and the bubbles to increase the oxygen dissolved amount, and a bubble discharge port for discharging bubbles passing through the sludge separation means to the outside of the reactor; and It is provided in the upper side of the reactor comprises a precipitation tank for precipitating sludge contained in the waste water.

Description

Water treatment device by gas dissolution and material separation {PROCESS AND PLANT FOR WASTEWATER TREATMENT}

The present invention relates to a water treatment device, and more particularly, by installing a sludge separation means inside the reaction tank, in the case of biologically treating wastewater, by effectively supplying air bubbles and separating materials to improve the water treatment efficiency. It is about.

In general, water treatment is a process of converting contaminated substances in water into substances stabilized by microorganisms or chemical oxidation and reduction reactions and separating untreated residues.

Therefore, water treatment is a technique for stabilizing and separating substances in various ways, such as water quality, organic matter, and nutrients. Currently, water treatment technologies are mostly biological treatment methods and relatively inexpensive.

However, this conventional biological water treatment method is very slow and unstable because it depends only on the rate of decomposition of organic matter in the natural state.

Therefore, the core of water treatment is the process of analyzing the factors that have an important influence on the water treatment and controlling the limiting part in the process of interacting with each other.

However, in the water treatment apparatus currently being developed, most of them are focused on the reaction process among the gas transfer process, the reaction process, and the material separation process, which are the key elements in the water treatment process, and thus the limitation of treatment efficiency appears.

Therefore, there is a need for a method for overcoming this limitation of processing efficiency.

Therefore, the object of the present invention is to solve the above problems, the object of the present invention is to improve the water treatment efficiency by effectively supplying the bubbles contained in the waste water and separating the substances by mounting a plurality of sludge separation means inside the reactor. It is to provide a water treatment apparatus that can be.

In order to realize the above object of the present invention, a preferred embodiment of the present invention includes a reaction tank having a means for generating air bubbles by supplying air to the waste water from the lower side; A sludge separation means for dividing the inside of the reaction tank into multiple stages to move the introduced waste water and bubbles in density order, and decomposing contaminants by increasing the oxygen dissolved amount by increasing the contact area of the waste water and bubbles; A bubble discharge port for discharging bubbles passing through the sludge separation unit to the outside of the reaction tank; And it is provided in the upper side of the reaction tank to provide a water treatment apparatus including a precipitation tank for precipitating sludge contained in the waste water.

Hereinafter, a water treatment apparatus according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

As shown in Figures 1 and 2, the water treatment apparatus proposed by the present invention is to slow down the moving speed of the waste water and bubbles introduced by partitioning the reaction tank (1) and the interior of the reaction tank (1) into several zones Sludge separation means (3) for separating the sludge by increasing the distance to increase the oxygen dissolved amount and varying the fluid movement speed between the upper and lower zones, and bubbles passed through the sludge separation means (3) outside of the reaction tank (1) A bubble discharge port (5) for discharging the gas, a settling tank (7) mounted inside the reactor (1) to settle sludge contained in the waste water, and circulation means (9) capable of circulating the waste water from each zone. do.

In the water treatment apparatus having such a structure, the reactor 1 is formed with a predetermined volume of empty space therein. Then, the waste water inlet 11 and the air inlet 13 is formed in the lower portion of the reaction tank (1). Therefore, waste water supplied from the outside is introduced into the reaction tank 1 through the waste water inlet 11. In addition, outside air is also introduced into the reaction tank 1 through the air inlet 13 and dissolved in waste water.

In addition, a sludge discharge port 15 is mounted at the bottom of the reactor 1. Therefore, the sludge deposited on the inner bottom of the reaction tank 1 is periodically discharged to the outside of the reaction tank 1 through the sludge discharge port 15.

At least one sludge separating means 3 is provided inside the reactor 1, and the inside of the reactor 1 is divided into several zones.

As shown in FIGS. 3 and 4, the sludge separating means 3 protrudes from the inner wall 17 of the reactor 1 and is arranged in a zigzag shape, and the support plate ( 19 is formed on the bottom of the concave-convex portion 21 to form a good environment for microorganisms to live, and protrudes below the media layer 23 to pass through the bottom of the media layer 23 And a media member composed of a wear (25) for uniformly dispersing bubbles.

The sludge separation means 3 having such a structure is formed in multiple layers inside the reactor 1 and is disposed in a zigzag shape with each other to form a passage 29 of wastewater moving upward.

The media layer 23 is provided with the uneven portion 21 on the bottom surface of the support plate 19. Then, the waste water and bubbles which rise from the bottom are in contact with the bottom surface of the media layer 23 proceeds in the direction of the arrow (Fig. 1), and in particular, the bubbles are in contact with the bottom surface of the media layer 23 due to buoyancy. You will proceed.

At this time, since the media layer 23 is uneven, the flow of waste water is slowed when the waste water and bubbles proceed in contact with the bottom surface of the media layer 23. Therefore, a certain amount of microbial biofilm can be continuously maintained in the media layer 23 due to the moving air and wastewater flow, so that it is the same as the initial microbial growth process on the surface of the media layer 23 without excessive adhesion even after a time. Microbial film is formed to create a good environment for the growth of microorganisms.

In addition, since the media layer 23 is formed in a concave-convex shape, since the surface area is geometrically wide, oxygen contained in the bubble can be supplied in sufficient contact with the microbial layer, thereby improving dissolved oxygen transfer rate and decomposition rate. have. As a result, the sludge separation means 3 prevents the generation of an anaerobic atmosphere that is likely to occur in the microbial treatment to create an aerobic condition.

The wear 25 protrudes downward from a predetermined position of the media layer 23, preferably in the middle portion, and has a shape in which the teeth 27 are continuous. Therefore, air and wastewater flowing along the bottom of the media layer 23 are uniformly distributed throughout the media layer 23 while passing through the teeth 27 of the weir 25.

In addition, when waste water and bubbles flow in contact with the media layer 23, bubbles and the like are positioned at adjacent positions of the media layer 23, and relatively high density sludge is located toward the lower direction.

On the other hand, Fig. 5 shows another embodiment of such sludge separation means. As shown, a micro-eye filter 35 may be applied in place of the concave-convex media member. The filter 35 removes the sludge contained in the waste water when the waste water passes through the filter 35.

Then, the waste water from which the sludge is removed moves to the upper portion of the filter 35 and is discharged to the outside through the discharge port 39. At this time, the shielding chamber 37 is sealed on all sides of the filter 35 is formed. Thus, the shielded chamber 37 stores purified water and some air that have been purified while passing through the filter 35, and the purified water is stored separately from the waste water that has not passed through the filter 35 and is externally discharged through the outlet 39. To be discharged. In this process, some air passes through the filter, thereby preventing the filter from clogging in advance.

At this time, the discharge port 39, the valve 41 is mounted to adjust the amount of purified water discharged.

In addition, the filter 35 may be formed in multiple stages in the reaction tank 1, and each outlet 39 may be mounted at each stage. Therefore, the wastewater can be purified and discharged to the outside in each step.

Referring again to FIGS. 1 and 2, a bubble collecting port 43 may be formed at one side of the media layer 23. The bubble collecting port 43 is formed by one end of the support plate 19 being bent at a predetermined angle and connected to the inner wall surface of the reaction tank 1. Accordingly, bubbles introduced through the air inlet 13 flow along the bottom surface of the media layer 23, and part of the bubbles are collected in the bubble collecting port 43.

Then, when the collected bubbles are collected in a certain amount and the air is discharged through the surrounding valve 42, the waste water of the upper portion may move downward momentarily by the discharged air volume to mix the sludge accumulated at the bottom of each zone.

As described above, the bubble collecting port 43 may be provided with another bubble collecting port 45 in the opposite direction as well as on one side.

In the embodiment of the present invention, it has been described that two bubble traps 43 are provided, but it is also possible to selectively provide bubble traps 43 in each of the media layers 23.

And, as described above, the waste water advanced to the upper portion of the reaction tank 1 is stored in the settling tank (7). At this time, the bubble discharge port (5) is disposed in the direction of the passage of the waste water and bubbles of the sludge separation means (3) located in the uppermost layer by the buoyancy before the bubble reaches the settling tank (7) by the buoyancy force Is captured and discharged to the outside.

In addition, the waste water stored in the sedimentation tank 7 is precipitated as the sludge sinks by specific gravity with time. The precipitated sludge is discharged to the outside through the discharge pipe 47, or moves backward in the reaction tank 1 to settle at the bottom of the reaction tank 1. Thus, waste water passes through the settling tank 7. While the sludge contained is precipitated, bubbles are discharged through the bubble discharge port 5, and the remaining treated water from which the sludge and the bubbles have been removed is discharged to the outside through the discharge pipe 47. Thus, the settling tank 7 is a reaction tank ( Since it is installed integrally on the upper part of 1), the sedimentation induction and discharge process are performed simultaneously without the need for a separate sedimentation process, thereby reducing the treatment time.

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Meanwhile, a circulation means 9 is provided outside the reactor 1, and the circulation means 9 includes circulation pipes 47 and 49 communicating with the media layers 23, and the circulation pipes 47, 49 includes an on / off valve 41 (FIG. 5).

Therefore, by operating the on-off valve 41, it is possible to periodically move the sludge precipitated in each media layer 23 downward.

Meanwhile, the media layer 23 of the water treatment apparatus according to the present invention may be arranged in a shape as shown in FIG. 6 instead of a zigzag shape.

Also in this case, the sludge separation means 3 is formed in a filter type as described above. That is, the filters 51 are arranged in a predetermined shape with each other, and the shielding chamber 53 is provided above the filter 51. Therefore, the purified water from which the sludge is removed through the filter 51 is discharged to the outside through the shielding chamber 53.

As described above, the water treatment apparatus according to the present invention is arranged in a plurality of sludge separating means in the reaction tank, and is an upflow type to purify the waste water and bubbles introduced from the bottom to purify.

Hereinafter, with reference to the accompanying drawings will be described in more detail the operation of the water treatment apparatus according to a preferred embodiment of the present invention.

1 to 4, in the case of treating wastewater using the water treatment apparatus according to the present invention, first, by opening the wastewater inlet 11 and the air inlet 13, the wastewater and air are discharged from the reactor 1. It flows inside.

At this time, the sludge contained in the introduced waste water falls from the position adjacent to the inlet to start to precipitate on the bottom surface 33 of the reaction tank (1).

Then, the remaining waste water and bubbles pass through the lower section 29 of the media layer 23, where low-density sludge is distributed near the media layer 23, and the relatively high-density sludge is the reaction tank 1. It is distributed on the bottom surface 33 of).

At this time, the waste water passing through the adjacent positions (P, Q) of the media layer (23) collides with the inner wall surface of the reaction tank (1) while proceeding in the direction of the arrow, and is accumulated in the lower part by the reverse flow generated at this time. The dense sludge flows in the opposite direction of the flow of waste water.

Therefore, as the wastewater flows in and the water treatment proceeds, the dense sludge gradually moves to the lower portion of the reactor 1.

As described above, the wastewater supplied from the lower portion gradually rises and proceeds along the passage 29 formed between the plurality of media layers 23, and in contact with the bottom surface of the media layer 23.

Then, the waste water is in contact with the concave-convex portion 21 of the media layer 23, the contact area is increased to slow the movement speed of the waste water. Therefore, since the time for contacting the waste water with the media layer 23 is increased and its amount is increased, the water treatment effect can be enhanced by being exposed to the aerobic environment formed in the media layer 23 for a long time.

In addition, the flow of wastewater becomes turbulent by the wear 25 installed at a predetermined position of the media layer 23, and the wastewater and bubbles are prevented from being biased in one direction by the uneven portion 21 to prevent the media layer 23. Make sure to spread evenly over the front.

In other words, while the waste water and bubbles pass through the weir 25, they are uniformly distributed by the teeth 27 of the weir 25. Therefore, waste water and bubbles are uniformly distributed over the entire surface of the media layer 23.

Through this process, the waste water gradually rising to the top is supplied to the settling tank 7. In this process, bubbles contained in the waste water do not move to the settling tank 7 due to buoyancy and are discharged to the outside through the bubble discharge port 5.

In addition, the waste water moved to the settling tank 7 is gradually settled down as time passes, and is discharged to the outside through the circulation pipe 47 or the sludge discharge port 15 after a predetermined time. In this way, the waste water is passed through the settling tank 7, the contained sludge is precipitated, bubbles are discharged through the bubble discharge port 5, the remaining treated water from which the sludge and bubbles are removed is discharged to the outside through the discharge pipe 47.

In addition, since the circulation pipes 49 are connected to the respective media layers 23, the open / close valves are selectively opened to periodically circulate the sludge deposited thereunder.

As described above, the wastewater introduced into the upflow water treatment device is purified while passing through a plurality of media means.

The wastewater was tested using the apparatus, and the following results were obtained.

Reactor Volume (Treatment Temperature) Wastewater Inflow / Outflow Concentration (mg / L) Processing time (H) Etc Aerobic treatment (one embodiment) 15 L (20 degrees) Sewage BOD 190/5 3 35% oxygen transfer rate Anaerobic Treatment (Other Embodiments) 15 L (35 degrees) Sewage Sludge VS 9300/2500 96 (4 days) Gas generation rate (CH4 / CO2)

As described above, the water treatment apparatus according to the preferred embodiment of the present invention has the following advantages.

First, by mounting a plurality of media layers inside the biological reaction tank to increase the moving distance and residence time of the bubbles to increase the dissolved oxygen transfer rate and stirring effect.

Second, since it is separated and concentrated up and down by the sludge density difference inside the reactor, it is possible to ensure a sufficient time for the waste water is removed by the microorganisms while maintaining a high concentration of microorganisms.

Third, it is possible to maximize the decomposition rate of the reaction tank by intensively supplying dissolved oxygen by forming bubble traps in each media layer to increase the stirring effect up and down.

Fourth, because the bubbles in the media layer during the abandonment process contacts the concave-convex portion, bubbles are always present and the biofilm layer is formed by causing turbulence to prevent anaerobic phenomenon.

Fifth, most of the aerobic and anaerobic microorganisms in the bottom of the upflow reaction tank to minimize the loss of microorganisms.

Sixth, since the settling tank is provided in the reaction tank itself, no separate settling facility is required.

Seventh, because the sedimentation induction and discharge of the discharged water without a separate precipitation time in the upper part of the reaction tank can reduce the treatment time and increase the activity of microorganisms.

Eighth, the sludge concentration can be adjusted according to the characteristics of the influent wastewater at the bottom by discharging the sludge at the lower part during the aeration process.

Ninth, by using the media, bubbles can directly contact the large geometrical specific surface area provided by the media, so that oxygen in the bubbles can be directly transferred to the media.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications can be made within the scope of the claims, the detailed description of the invention, and the scope of the accompanying drawings. It goes without saying that it belongs to the scope of the present invention.

1 is a cross-sectional view of a water treatment apparatus according to a preferred embodiment of the present invention.

FIG. 2 is a sectional view taken along the line "A-A" in FIG.

3 is a bottom perspective view showing the sludge separation means shown in FIG.

4 is a side view of the sludge separation means shown in FIG.

Fig. 5 is a sectional view showing another embodiment of the sludge separation means according to the present invention.

Fig. 6 is a sectional view showing another embodiment of the water treatment device according to the present invention.

Claims (8)

A reaction tank having wastewater introduced from below and having means for supplying air to the inflowed wastewater to generate bubbles; A sludge separation means for dividing the inside of the reaction tank into multiple stages to move the introduced waste water and bubbles in density order, and decomposing contaminants by increasing the oxygen dissolved amount by increasing the contact area of the waste water and bubbles; A bubble discharge port for discharging bubbles passing through the sludge separation unit to the outside of the reaction tank; And A water treatment device comprising a precipitation tank provided inside the upper side of the reaction tank to precipitate the sludge contained in the waste water. According to claim 1, The sludge separation means are each projected from the inner wall of the reaction tank is arranged in a zigzag shape, the support plate to form a waste water passage on one side, and formed in the concave-convex shape on the bottom of the support plate to live microorganisms And a media member comprising a media layer forming a favorable environment, and a wear which protrudes below the media layer and uniformly distributes air bubbles passing through the bottom surface of the media layer. The water treatment apparatus of claim 2, wherein the wear has a sawtooth shape protruding downward from the media layer and uniformly distributes waste water and bubbles by the sawtooth. According to claim 2, One side end of the support plate is bent at a certain angle is connected to the inner wall of the reaction tank to form a bubble collecting port to induce agitation by the amount of waste and movement speed moving downward by the bubble volume in accordance with the discharge of the bubble Water treatment device. According to claim 1, The sludge separation means are each protruding from the inner wall of the reaction tank is arranged in a zigzag shape, forming a waste water passage on one side, and a filter for removing the sludge contained in the waste water, and is mounted on top of the filter And a shielded chamber for separating purified water and waste water. The water treatment apparatus according to claim 5, wherein the shielding chamber is disposed on an upper surface of the filter and sealed in all directions so that some air and purified water introduced through the filter can be discharged to the outside through a circulation pipe protruding outside the reaction tank. The water treatment apparatus according to claim 1, wherein the bubble discharge port is disposed in the direction of a passage through which waste water and bubbles rise in the sludge separating means located in the uppermost layer, so that the bubble collects by the buoyancy to the bubble discharge port before reaching the settling tank. The water treatment system of claim 1, further comprising a circulation pipe which is mounted on the outside of the reactor and communicates with the upper space of the sludge separation means, and an opening and closing valve mounted to the circulation pipe. Device.