KR200168716Y1 - Wastewater treatment system based on extended tapered aeration and intermittent decant continuous feed single reactor - Google Patents

Abstract

The present invention discloses a wastewater treatment system. The present invention is based on the long-term aeration method. Forging type continuous inflow and long-term taper-type intermittent wastewater treatment which intermittently mixes intermittent aeration and tapered aeration, permits continuous inflow of wastewater, and intermittently discharges the supernatant. It's about the system.

Wastewater treatment system according to the present invention, the BOD concentration of the influent wastewater is equalized, the influent chamber to allow the influent wastewater to flow into the first reactor via the influent reservoir plate at a flow rate of less than a certain flow rate, and the inflow chamber After the waste water has been abandoned or aerated for a certain time, the first reactor to allow the second reactor to flow through the aeration tank reservoir plate to maintain the flow rate below a small flow rate, and a small amount of waste sludge produced in the aeration period is intermittently discharged. In the non-aeration period, the second reactor, which is in a quasi-anaerobic state and proceeds to the denitrification process, by a pump chamber / sump well and a blower for discharging the symbolic water by opening and closing the electric valve using a direct pump or siphon principle to the discharger. It is provided with a blower room for blowing the air to the mountain machine.

This system is very simple in structure, requires less site, and the operation is performed automatically or semi-automatically, which greatly reduces initial investment, operation management and maintenance costs, and the removal rate of organic matter, nitrogen and phosphorus in influent wastewater is very high There is no concern about eutrophication of rivers, odors are not detected in the operating plant, and no odors can be detected in the runoff, and there is little vibration or noise, which is a very environmentally friendly wastewater treatment system.

Description

Wastewater Treatment System based on Extended Tapered Aeration and Intermittent Decant Continuous Feed Single Reactor

The present invention relates to a wastewater treatment system. In particular, forging-type continuous inflow and long-term incorporating intermittent and tapered aeration, allowing continuous inflow of wastewater and intermittent discharge of supernatant water based on the long-term aeration method. It relates to a tapered aeration intermittent discharge wastewater treatment system.

1 is a representative process diagram of the activated sludge method which is according to the prior art and currently used most in each country. As shown in FIG. 1, when the sewage flows into the primary sedimentation basin, sludge is precipitated, and the symbolic water of the primary sedimentation basin flows into the aeration tank, and after a given time, MLSS flows into the secondary sedimentation basin. As time passes, the activated sludge is settled, and the symbol water of the secondary settler is discharged after the sterilization treatment for sterilization is performed in some cases.

On the other hand, the sludge precipitated in the primary and secondary sedimentation basin is concentrated in the concentration tank, which is introduced into the anaerobic digestion tank warmed to 30 to 35 ℃ and the organic matter introduced through the residence time before and after 30 days is digested to a large amount Methane gas (CH ₄ ) and carbon dioxide (CO ₂ ) are produced, while the digested sludge is discharged, which is dehydrated by a dehydration device.

Here, a part of the activated sludge of the secondary settling basin is introduced into the aeration tank as a return sludge, which is used to control the F / M ratio (Food to Microorganism, the ratio of food to microorganisms), and the remainder is introduced into the thickening tank as waste sludge. Concentrated with sludge.

The conventional activated sludge method as described above requires a lot of construction cost, operation cost, and maintenance cost, requires high technical skill due to high operating specifications, and it is difficult to remove organic matter more than 90%, and nitrogen and phosphorus removal rate is high. Very few streams can be eutrophiced, and odors, noise, and vibrations are large, resulting in non-environmentally friendly problems.

Therefore, the object of the present invention, which was devised to solve the problems of the prior art operating as described above, is to control the sequence according to the intended level by the water level sensor and the timer. It is to provide a forged continuous inflow and long-term tapered intermittent wastewater treatment system that can be easily and very good effluent quality, and to be a system capable of automatic operation.

1 is a representative process diagram according to the conventional activated sludge method.

Figure 2 is a perspective view of the structure of the wastewater treatment system according to the present invention.

3 is a plan view of FIG.

4 is a cross-sectional view taken along line BB ′ of FIG. 3.

5 is a cross-sectional view taken along the line AA ′ of FIG. 2;

6 is a block diagram of a sequence control panel.

7 is a perspective view of the floating ejector.

8 is a cross-sectional view taken along line C-C 'in FIG.

9 is a side view of FIG. 7;

10 is a bottom view of FIG. 7.

FIG. 11 is a detail view of portion A of FIG. 9; FIG.

12A and 12B are detailed circuit diagrams of FIG. 6.

<Explanation of symbols for the main parts of the drawings>

1: inlet pipe 2: inlet chamber

3: outlet 4: influent storage plate

5: Outflow water opening 6: First reactor

7: Aeration tank reservoir plate 8: Aeration tank reservoir plate opening

9: acid machine 10: second reactor

11: floating discharger 12: discharge hose

13: partition wall 18: pump chamber / sump well

19: electric valve 20: discharge pump

21: blower room 22: blower

30: inlet chamber outer wall 49: normal position

50, 83: magnet coil 51: start 2 switch

53, 85: time limit B contact 54, 67, 75, 79: B contact

55, 71, 84: Time A contact

56,57,62,63,65,69,73,77,81,87,89,90,94,99,100,106: A contact

58, 74, 91: timer 59, 60, 86, 96, 102: water level sensor

61, 64, 72, 88, 98, 104: relay

66: warning light 68, 76, 93: green light

70, 78, 95: Red light 80, 82: Actuator

101: high water level indicator 107: buzzer

59: high water level 1 sensor of the reactor 60: high water level 2 sensor of the reactor

86: low water level sensor of the reactor 96: high water level sensor of the reactor

102: boundary level sensor of the reactor

108: warning alert level 150: sequence control panel

301: inlet 302: air tank

303: valve type valve 304: hinge

305: exhaust pipe 500: low water level sensor of sump well

501: high level sensor of sump well

502: highest level sensor of sump well

BOD: biochemical or biological oxygen demand

MLSS: Mixed Liquor Suspended Solids

F / M ratio: food to microbial ratio

PLC: programmable logic controller

One preferred embodiment of the wastewater treatment system according to the present invention devised to achieve the object as described above, equalizes the BOD (Biochemical or Biological Oxygen Demand) concentration of the influent wastewater, at a flow rate below a certain flow rate An inlet water chamber (2) through which an inlet water storage plate (4) is introduced into the first reactor (6); A first reactor (6) allowing the wastewater introduced from the inlet chamber to be introduced into the second reactor (10) via an aeration tank reservoir (7) for maintaining a constant flow rate after being abandoned or aerated for a predetermined time; A second reactor (10) for intermittently discharging waste sludge produced in the aeration period and making the denitrification process in a non-aerobic state during the aeration period; A pump chamber / sump well 18 for discharging the supernatant water by opening and closing the electric valve using the pump direct type or the siphon principle to the discharger 11; And a blower chamber 21 for blowing air to the acid machine 9 by the blower 22.

In the present embodiment, the first reaction vessel 6 and the second reaction vessel 10 are partitioned by the aeration tank reservoir 7, and aeration tank reservoir plate opening 8 is provided at the lower end thereof. An inflow pipe 1 is installed inside the inflow chamber 2, and an inlet 3 level of the inflow water is positioned below a low level of the entire reaction tanks 6 and 10, and the inflow reservoir 4 is an inflow water. It is preferable to locate 1 to 3 m downstream from the outer wall of the chamber.

In addition, the inlet water storage plate 4 is provided with an opening 5 at the top of the high water level 1 (HWL1) 59, and an air diffuser 9 is provided at the bottom of the inlet chamber 2 and the entire reactors 6 and 10. Is installed. Progress of the denitrification process in the second reactor 10 causes the removal of nitrogen and phosphorus at a high rate, and the floating discharger 11 floats on the water surface in the middle of the second reactor 10. And an air tank 302 for maintaining a buoyancy suitable for fixing the floating discharger 11 to a predetermined level.

The floating discharger 11 is provided with a lid-type valve 303 for taking in the clearest portion of the symbolic water, the floating discharger 11 may be installed in parallel in addition if necessary. And it is preferable that the floating discharger 11 is installed to discharge and discharge the symbol water of 20 to 30cm under the water surface.

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

The present invention proposes that the national government requires sewage and low concentration livestock wastewater discharged from residential complexes and general cities with a waste water treatment capacity of 100,000 tons / day and wastewater discharged from various restaurants (hereinafter collectively referred to as wastewater). Wastewater treatment facilities that can obtain the effluent meet the effluent standard, the construction cost is lower than the conventional treatment facility, the operation is very easy and the maintenance cost is very low, while the effluent water quality is much better than the conventional.

The basic principle of the present invention is based on the long-term aeration method, a mixture of intermittent aeration and tapered aeration allows for continuous inflow of wastewater, and the discharge of symbolic water is intermittently performed.

In more detail, the wastewater treatment system according to the present invention is composed of a single water tank, and thus there is no need for facilities such as an inflow control tank, a primary and secondary sedimentation basin, a concentration tank, and an anaerobic digestion tank.

In the design of the sewerage system, if the average daily wastewater flow rate is multiplied by the peaking factor of 1.0 to 2.5, and the size of the reactor is determined based on this, it is proved that there is no problem in the treatment without installing the influent adjustment tank. It is also economically advantageous, so the adjustment tank can be excluded.

The wastewater flowing into the fore end of the forging facility is adjusted to a flow rate below a certain flow rate, flows into the first reactor 6 with a high concentration of dissolved oxygen, and flows out of the first reactor at a predetermined flow rate. The suspension flows into the second reactor 10 having a low supply concentration of dissolved oxygen. In the first and second reactors, both give up for a certain period of time and then stop giving up for a certain period of time, thereby intermittently giving up the anaerobic state of the reactor. That is, when the inside of the reactor becomes aerobic by aeration, oxidation and nitrification of organic substances by aerobic microorganisms occur.

After the abandonment period (approx. 120 minutes) and the aeration period, the gravity settles for a certain period (approximately 60 minutes), and then discharges clear symbolic water for a certain period (approx. 60 minutes). The anaerobic or quasi-anaerobic state leads to denitrification and dephosphorization by microorganisms.

At this time, the outflow of the symbolic water is not to use a massive weir (weir) as in the prior art, it is to use only a specially designed floating ejector 11 to always inflow and discharge only the clearest symbolic water.

At the end of the discharge process, return to the abandonment cycle. This time adjustment takes the driver TLR1 in the level switch 102, 96, 59, 60 and 86 and the sequence control panel 150 into consideration, in consideration of the inflow and outflow water quality. (58), TLR2 (74) and TLR3 (91) by combining the enemy.

The adjustment of this timer can be done automatically once in a long time according to the flow rate and organic concentration of the influent wastewater, the organic concentration of the effluent, and the season, and the outflow BOD concentration from this system is less than 20ppm. Significant amounts of phosphorus and nitrogen that are maintainable and rarely removed in conventional devices are also removed.

As this system is easier to operate than the conventional one, and the facility size is less than half of the conventional device, the construction cost and maintenance cost are also proportionally less, which is very economical and the effluent water quality is much better than the conventional one, and the automatic operation is It is possible.

The present invention is to reduce the conventional operation complexity, excessive construction cost and maintenance cost, and to significantly improve the quality of the effluent. The present invention provides the inside of the forged water inlet chamber (2) and the first reactor (6). , The second reactor 10, the pump chamber / sump well 18 and the blower chamber 21 are partitioned.

The influent chamber 2 contributes to equalizing the BOD concentration of the influent wastewater, and is a reservoir plate, which is a rectifier for flowing the influent wastewater into the first reactor 6 at a flow rate below a certain flow rate. It enters into the 1st reaction tank 6 via 4). In addition, the inlet chamber (2) is provided with a minimum acid machine 9 for preventing the deterioration of the influent wastewater.

The first reactor 6 has a volume equal to 1/4 of the volume of the entire reactors (first and second reactors) 6 and 10, and the diffuser 9 is appropriately arranged at the bottom. In one place, the wastewater enters the second reactor 10 through the aeration tank reservoir plate 7 which is maintained after a certain period of time, or aerated, and kept below a certain flow rate. .

The biggest reason for blocking the aeration tank reservoir plate 7 between the first and the second reactors 6 and 10 to make a compartment is that the oxygen demand by the microorganism is the total reaction tank because the BOD concentration in the first reactor 6 is the maximum. This is because it is known to be much larger than the average oxygen demand of.

The volume of the first reactor 6 is only 25% of the total reactor volume, but the actual oxygen demand is 35% of the total amount. Therefore, the diffuser 9 is also installed to have the ability to supply sufficient oxygen required here.

Therefore, in the first reactor 6, a dense suspension suspended solids (MLSS) is produced by aerobic microorganisms with the highest organic concentration and sufficient oxygen supply of the influent wastewater, and a sludge blanket under the first reactor 6 during the aeration period. ), That is, a natural high density microbial membrane is formed, which serves to adsorb and filter organic matter and suspended matter in the influent wastewater.

At this time, even if there is no aeration tank storage plate (7), if the flow rate from the first reactor (6) to the second reactor (10) exceeds a certain flow rate, the formed dense biofilm is destroyed and the influent wastewater is directly in the second reactor ( 10) can be greatly impaired processing efficiency.

The second reactor 10, which is operated by extended aeration, is also a place where the diffuser 9 is properly placed on the bottom. Wall water level alarm (Alarm Water Level Switch) 102, Top Water Level Switch (96), High Water Level 1 (HWL1) (59), High Water Level 2 (HWL2) (60) and A low water level sensor (LWL) 86 is attached at a position where the water depth is appropriate.

During the abandonment period of the second reactor 10, the microorganisms are operated at a very low F / M ratio (0.05 to 0.2 g BOD / g.MLSS.d) and are in an endogenous respiration phase due to lack of nutrition. Since activated sludge is produced with very good sedimentation and the removal rate of BOD is very high, the amount of waste sludge produced is only 20 to 25% of the conventional one, and can be discharged intermittently.

Therefore, the installation of the solid-liquid separator including the concentration tank is unnecessary, and the processing cost is much lower than that of the conventional one. On the other hand, during the aerobic period, it becomes semi-anaerobic and denitrification proceeds to remove nitrogen and phosphorus at a high rate.

In the middle of the second reactor 10, a floating discharger 11 floats on the water surface, which may be directly connected to the discharge pump 20 by the discharge hose 12, and an electric valve 19 at the end of the discharge hose 12. ) Can be used to discharge symbolic water using the principle of siphon. In the latter case, the pump chamber 18 serves as a sump well.

Conventionally, we use a weir to discharge the symbolic water, so the facility is not only huge but also floats such as scum are mixed into the effluent, but this floating discharger 11 always uses only the clearest symbolic water. There is a big advantage to take. In addition, since it is floating, there is an advantage of using the surface of the existing reactor 10 without a large facility.

A discharge chamber 20 is provided in the discharge chamber of the supernatant water, that is, the pump chamber 18 or the sump well, and the blower chamber 21 is provided with a blower 22 for blowing air to the acid machine 9. The reason they are installed inside the system is due to vibration and noise considerations.

Hereinafter, the configuration and operation of the forging continuous inflow and long term tapered intermittent wastewater treatment system will be described in detail with reference to the accompanying drawings.

It is assumed that the operation of the system is given up for two hours and is given up for two hours. Therefore, if this example is selected in the following description, it is 6 cycles (6 cycles / day) during one day.

Now, the description of the structures and equipment of the present invention and the operation thereof will be described.

That is, the inlet pipe 1 installs a pipe having a diameter corresponding to the inflow rate in the inlet chamber 2, and the water level of the outlet port 3 of the inlet water is lower than the low water level (LWL) 86 of the reactors 6 and 10. Location and have as little outlet head as possible.

And an inflow water storage plate (baffle) 4 is used as a rectifier. The installation position may be changed according to the treatment capacity in the inlet chamber outer wall 30, but at least 1m downstream, and the reservoir plate 4 is provided with an opening 5 above the HWL1 (59) line. do.

A minimum diffuser 9 is installed at the bottom of the influent chamber 2. This influent chamber (2) contributes to equalizing the BOD concentration of the influent wastewater, and the acid generator (9) is installed to a minimum so that the influent does not deteriorate even when the inflow of the influent is stopped for a long time. The opening area is determined so that the average flow velocity of the wastewater passing through the inflow water outlet 5 is in the range of 0.08 to 0.16 m / s.

The reason for limiting the flow rate is to prevent short circuiting or local eddy currents from adversely affecting the processing performance.

Next, the first reactor 6 and the second reactor 10 will be described.

The size of the first reactor (6) is to install aeration tank reservoir (7) downstream of a quarter of the total length of the sum of the length of the first reactor (6) and the length of the second reactor (10) and the bottom of the aeration shell (8) is installed. In addition, an acid generator 9 is installed at the bottom of the first reactor 6.

The reason why the aeration tank reservoir 7 is installed in a quarter downstream of the volume of the entire reactors 6 and 10 is that the oxygen demand by the microorganisms is high because the concentration of BOD in this zone, i.e., the first reactor 6, is maximum. It is known that it is much larger than the average oxygen demand of the entire reactor. Therefore, the installation of the diffuser 9 must also be capable of supplying enough oxygen.

In fact, the oxygen required here is about 35% of the oxygen demand (mg / L) of the entire reactor (first and second reactors). In this situation, the metabolism of microorganisms is high, so the mixed liquor suspended solids (MLSS) or bio-mass or biological floc (MLSS) produced at this time are not allowed to stop blowing. In the lower part of the first reactor (6) is formed a dense biofilm, the influent wastewater that continues to flow even during the aeration period is prevented from being adsorbed and filtered in the course of passing through the biofilm to directly enter the second reactor (10) Help improve processing efficiency. Of course, the first and second reactors 6 and 10 enter the abandonment period at the same time and at the same time the aeration period.

In addition, the biofilm absorbs large amounts of BOD and suspended solids (approximately 65%), absorbs significant amounts of nitrogen and intake from the wastewater, and inhibits the growth of filamentous organisms so that sludge bulking does not occur. It also plays a role.

The mixed liquid suspended solids (MLSS) of the first reactor (6) is introduced into the second reactor (10) at a flow rate of 0.08 to 0.16 m / s through the opening (8) of the aeration tank reservoir (7). The reason for the flow rate limitation is the same as the reason for limiting the flow rate of the first reactor (6).

The volume of the second reactor 10 corresponds to three quarters of the volumes of the entire reactors 6 and 10. The acid reactor 9 is also installed at the bottom of the second reactor 10, and an acid generator 9 is installed to satisfy about 65% of the total oxygen demand (mg / L) of the reactor. Going toward the rear end of the second reactor 10, the BOD concentration decreases, but as the BOD decreases, the oxygen demand decreases with this. The layout of the acidifier 9 is set to a quantity suitable for the oxygen demand.

This is because the microorganisms in the end stage of the second reactor 10 is in the endogenous respiration phase due to lack of food, so only a small amount of oxygen is required. And the characteristic of microorganisms grown in endogenous growth stage is that precipitation is very good.

The first and second reactors 6 and 10 have been described so far in relation mainly to the oxygen demand. In other words, in the first reactor (6), the concentration of organic matter is high, the oxygen demand is about 35% of the entire reactor (6,10), the metabolic rate is high, that is, the oxygen demand in the second reactor (10) is As mentioned above, the microorganisms at the rear end are in a very severe endogenous growth stage as described above.

This is a kind of tapered aeration, which supplies a lot of oxygen where there is a high demand for oxygen and a small supply where there is less demand, so that the size of the blower 22 can be reduced. As a theoretical and economical aeration method that can reduce the cost, the advantage is different from the method of supplying oxygen evenly in the conventional activated sludge method.

In addition, this treatment system adopts extended aeration. As is well known, the main factor in designing this method is the ratio of organic matter to microorganism, that is, F / M ratio of 0.05 to 0.2 gBOD / g.MLSS.d, The mean cell residence time (Mean Cell Residence Time) is 16 to 36 days, the volume load of the BOD is 150 to 500 gBOD / m 3 · d, the concentration of the mixed liquid floating solids (MLSS) is 1,500 to 9,000 mg / L.

If these design parameters are also satisfied when operating, it is already known that the final effluent water quality of this system is more than 95% of BOD removal and that the production of waste sludge is only 20-25% of the standard activated sludge process. This is well known to the skilled technicians.

In addition, general long-term aeration, which is performed only by net long-term aeration, is not found in this treatment system.

Nitrification generally occurs when the oxygen supply is adequate and the mean cell residence time is more than 10 days. Since the average microbial retention period of this system is 16 to 36 days, inevitably nitrification occurs well.

Nitrification refers to the conversion of ammonia nitrogen (NH ⁺ ₄ -N) to nitrate nitrogen (NO ^- ₃ -N) by the nitrifier. During the nitrification period, that is, during air-on, there are sufficient dissolved oxygen (DO, O ₂ ) in the reaction tank and nitrification is carried out in two stages by the action of Nitrosomonas and Nitrobacter, which are autotrophic nitrifying microorganisms belonging to aerobic microorganisms (aerobe). Happens.

In the first step, Nitrosomonas oxidizes ammonia nitrogen (NH ⁺ ₄ -N) to produce nitrite ionic nitrogen (NO ^- ₂ -N), while Nitrobacter oxidizes the resulting nitrite to nitrate ionic nitrogen (NO ^- _3- ). N) If the nitrate produced by this process is introduced into the river or the sea without any treatment, the release of nitrates should be prevented because eutrophication can occur and cause a great adverse effect on the environment. In fact, most of the secondary treatment plants currently operating release this nitrogen component almost as it is.

Next, the aeration period will be described. When the blowing is stopped (2 hours) for a predetermined period of time, and then the blowing is stopped (2 hours), the suspension of the mixed liquid suspension freely moving inside the reactors (6, 10) due to the interruption of the air discharged from the acid generator (9). The movement is stopped.

The very small F / M ratio of 0.05 to 0.2 corresponds to the endogenous growth phase in the microbial growth phase. The microorganisms grown at this stage are very good in sedimentation and settle slowly as the air is stopped.

During the abandonment period of this treatment system, the mixed solution suspension is collected in 1,000 mL graduated beaker and settled for 30 minutes in the second reactor 10, and the capacity of the settled sludge is 30 to 50% of the total capacity. The sludge volume index is easily in the range of 50 to 150 mL / g.

Meanwhile, the dissolved oxygen concentration in the reactors 6 and 10 decreases gradually over time during the aerobic period, and finally enters the anaerobic zone to undergo denitrification. In the denitrification process, the air-off period, the concentration of dissolved oxygen in the reaction tank may be zero (ppm), even in an environment where there is a certain amount of dissolved oxygen (0.4 mg / L) in the reaction tank. Proceeds.

In this process, nitrates (NO ₃ ) undergo two stages of catabolism (oxygen decomposition). In other words, this action is performed by anaerobic microorganisms (Anaerobe) that can reproduce in an environment free of random microorganisms (Facultative) and dissolved oxygen.

That is, in the anaerobic region, nitrates (Nitrate, NO ₃ ) lose one oxygen by the action of microorganisms and become nitrite (Nitrite, NO ₂ ). It is converted into nitric oxide (NO), nitrous oxide (Nitrous oxide, N ₂ O) or nitrogen gas (N ₂ ) by the action of microorganisms. This nitrogen molecule is released into the atmosphere because it is a gas, while the oxygen molecule (O ₂ ) liberated in the denitrification process is used by the microorganism. This is as shown in equation (1).

This denitrification occurs during the air-off period when the influent wastewater continues to flow in and removes more than 95% of the nitrogen content in the influent wastewater without any help from agitators. For reference, if the nitrogen removal rate of 95% is applied when the nitrogen concentration of the influent wastewater is 30 mg / L, the removal amount is 28.5 mg / L and the amount of outflow contained in the effluent is 1.5 mg / L.

Therefore, since most of the nitric acid (NO ₃ ) produced during nitrification is removed from the system and only a small amount flows out into the stream, it does not cause an environment such as eutrophication.

After 1 hour of the selected aeration period (2 hours), the sludge in the second reactor 10 is stabilized, and a transparent symbolic water is collected in the upper layer. This symbol water is naturally discharged or discharged to the sump well 18 through the discharge hose 12 and the static valve 19 connected to the discharge pipe 305 of the floating discharger 11 using the siphon principle. One of the methods of directly connecting the discharge pump 20 to 12 may be discharged.

At this time, opening and closing of the electric valve 19 and ON / OFF of the discharge pump 20 are designated by the sequence control panel 150. When the flow rate flowing into the inlet 301 of the floating discharger 11 is above a certain value, the sludge is floated to discharge the sludge to the outside, so that a special device, that is, the floating discharger 11 is used to prevent this. do.

The detailed view of the floating discharge machine 11 is as shown in Figs. 7 to 10 and the basic operation principle thereof is as follows.

The reason why the floating discharger 11 is floated at a certain depth of the water is to inject and discharge only clear symbol water of about 20 to 30 cm below the water to avoid scum on the surface of the water. In other words, the water level of the inlet 301 is always at a certain depth in the water surface so that only the clearest symbol water can be collected and discharged at all times. Therefore, it is provided with an air tank (302) (Float) for maintaining the buoyancy suitable for fixing the floating discharger (11) to a certain water level.

The cross-sectional area of the inlet 301 of the floating discharge unit 11 is sufficiently small (0.02 to 0.20 kPa) so that the inlet flow rate is sufficiently small to prevent the precipitated sludge from floating out and flowing out. If the required inlet 301 area is insufficient to one floating ejector 11, it may be installed in addition to the floating ejector 11 in parallel.

The lid valve 303 of the floating discharge unit 11 is attached to the floating discharge unit 11 body by a hinge 304 having a low resistance. When the discharge water is discharged to the flexible discharge hose 12, the valve-type valve 303 opens to the upper side to allow water flow by the hydraulic principle, otherwise, that is, the discharge pump 20 is stopped or the static valve If 19 is closed and water is not discharged to the discharge hose 12, the inlet 301 is closed by the self-weight of the valve valve 303, and this state is maintained until the next cycle. Of course, the specific gravity of the valve-type valve 303 material is selected to use greater than 1.0.

The reason why the valve-type valve 303 is installed at the inlet 301 is as follows. During the aeration period, if the lid-type valve 303 attached to the inlet 301 as shown in detail A in FIG. 10 is not open or installed, the inlet 301 is filled with a mixed liquid suspended solids (biomass). After stopping the abandonment, when the sedimentation process is finished and discharge is started, most of the mixed liquor suspended solids inside the inlet 301 are discharged to the outside through the floating discharge machine 11, which may lower the discharged water quality. It is the role of the cap valve 303 to prevent.

In this way, when the discharge is completed, that is, when the aeration period is completed, it goes back to the abandon cycle by the sequence control command described next. Abandonment tanks are almost anaerobic because they belong to the aeration cycle during the earlier stages of the abandonment cycle. Once the aeration cycle is started, the dissolved oxygen concentration in the reactors (6, 10) cannot rise rapidly.

Dissolved oxygen concentration gradually rises and as time passes, the state in the reactor (6,10) may become an aerobic state where, after some time, the aerobic microorganisms can finally act as the concentration of dissolved oxygen gradually increases from the anaerobic state. . As described above, the nitrogen removal capability of the system is very high because it is quasi-anaerobic for a considerable period of time until it becomes aerobic even after entering the aeration cycle.

Next, Phosphorus removal will be described. Since it is an important factor for eutrophication with Indian nitrogen, it is desirable to remove as much as possible before leaving the treatment plant. General municipal wastewater has three forms: ① Organic Phosphorus, ② Ortho-phosphorus and ③ Condensed Phosphorus.

When biologically treating wastewater with this system, microorganisms assimilate orthoin (PO ₄ ^3- ) during their growth. However, condensed phosphorus (P ₂ O ₇ ^4- , P ₃ O ₁₀ ^5- ) is hydrolyzed by enzymes before being assimilated into the form of orthoin. If the wastewater does not form biological floc by special chemicals, the only way to remove phosphorus in biological wastewater treatment like this treatment is to assimilate.

Such removal refers to the storage of phosphorus in microbial cells, which is called luxury uptake. Because this luxury uptake removes a significant amount of phosphorus during the aeration period, even if such a small amount flows into the stream, no adverse effects of eutrophication occur.

On the other hand, the circuit for controlling the system of the present invention is implemented in various ways, but in the present invention only the embodiment by the sequence control circuit will be described. However, it is obvious to those skilled in the art that the present invention is not limited to the sequence control circuit described below. That is, the sequence control circuit described below can be easily implemented by a programmable logic controller (PLC).

Hereinafter, the contents of the automatic operation of the system will be described through sequence control at the normal position 49 with reference to FIGS. 12A and 12B. As an embodiment of a control panel for controlling the system, a sequence control panel 150 is installed outside the facility.

Depending on the water quality of the influent wastewater, the average urban, home or restaurant wastewater can achieve good results by operating the system of the present invention every four hours. In other words, the abandonment is continued for two hours, and the abandonment period is set for two hours. One hour out of the two periods during the non-spray period is the settling period and the remaining one hour is the discharge period. Think of it as a daily unit, which is 6 cycles. During the 2 hours of abandonment, as described above, oxidation and nitrification of organic substances by aerobic microorganisms proceed.

During 2 hours of aeration, the precipitation process proceeds and as time passes, the denitrification process is carried out by random microorganisms and anaerobic microorganisms as the anaerobic degradation of the reactor (6,10) proceeds. As described above, the nitrogen gas (N ₂ ) When discharged into the atmosphere, when one hour of the non-aspirated two hours has elapsed, when the symbol water is discharged for one hour by the floating discharge machine (11), aeration is started again.

Such sequence control details will be described below with reference to FIGS. 12A and 12B. First, in FIG. 12A, when the start switch 1 (START1) 40 is pressed, the magnet coil MC5 42 of the inflow pump is excited when the transfer switch is switched to No. 1, and the magnet when the transfer switch is switched to No. 2. Coil MC6 (44) is excited and the auxiliary contact (MC5-1a / MC6-1a) 43 is closed to operate the inlet pump.

The inflow pump is stopped by artificially pressing the stop button 1 (STOP1) 41 or by the operation of the thermal relay TH (not shown) due to the overload of the line.

The green lamp 4 (GL4) 46 is turned off and the red lamp 4 (RL4) 48 is turned on when the inflow pump is operated.

Now assume that the influent wastewater to be treated is general wastewater, and first set the timers TLR1 (58), TLR2 (74) and TLR3 (91) in the control panel 150 to 120 minutes, 60 minutes and 60 minutes, respectively. Can be arbitrarily selected by influent BOD concentration, temperature, flow rate, effluent water quality, etc.) When normal voltage is applied to the control panel circuit, the green lights GL4 (46), GL1 (68), GL2 (76) and GL3 (93) light up respectively. do.

When the transfer switch 49 is in the normal position and the start button START2 (51) is pressed, the magnet coil MC1 / MC2 (50) is excited and the contacts MC1-1a / MC2-1a (57) are closed to close the start circuit. Voltage is applied to TLR1 58 to start timer TLR1 58.

When the magnet coil MC1 / MC2 50 of the blower 22 is excited by the ON of the START2 51, the blower 22 is operated.

Therefore, the contact MC1-b / MC2-b (67) is opened and the green light GL1 (68) is turned off while the contact MC1-2a / MC2-2a (69) is closed and the red light RL1 (70) is lit to turn on the blower ( 22) is in operation.

Although the water level in the second reactor 10 reaches the high water level 1 (HWL1) 59 even though the ecology of which the timer TLR1 58 has not reached the set time (2 hours) during the operation of the blower 22 is in contact with the high water level 1 HWL1 ( If 59) is CLOSE, HWL2 (60) is 5 cm below the level of HWL1 (59), so HWL2 (60) is already closed when the contact point of the first high level is closed. When the XA 61 is excited and the contact XA-1a 62 is closed, the relay XA 61 circuit is self-holding, and at the same time, the XA-2a 63 contact is closed and the relay XB 64 is excited. Therefore, the contact XB-b 54 is opened, the power supply of the magnet coil MC1 / MC2 50 is cut off, and the blower 22 is stopped.

However, prior to this, the operation of the timer TLR1 58 is maintained because the circuit of the timer TLR1 58 is in the CLOSE state by the CLOSE of the relay XA-3a 56 contact.

And even if the power of the magnet coil MC1 / MC2 (50) is cut off, since the contact XA-3a (56) is in a closed state, power is continuously supplied to the timer TLR1 (58) to continue operation until the set time (2 hours). .

Further, the contact XA-2a (63) is closed by excitation of the relay XA by the close of the high water level 1 (HWL1) 59, which excites the relay XB (64) to close the contact XB-a (65) Lights up the warning light HWL 66 to indicate that is at high water level 1.

When the set time (2 hours) of the timer TLR1 58 is reached, the time-contact TLR1-b 53 is opened, the power supply of the magnet coil MC1 / MC2 50 is cut off, and the blower 22 is stopped. The magnetic holding circuit is released by OPEN of -1a / MC2-1a 57, and the power supply of the timer TLR1 58 is also cut off, and the contact TLR1-a (time limit) 71 is closed.

At the same time, the red light RL1 (70) is turned off by the OPEN of the contact MC1-2a / MC2-2a (69), and the green light GL1 (68) is lit by the return of the contact MC1-b / MC2-b (67) and the blower (22) ) Indicates that it is idle.

When the time-contact TLR1-a (71) is closed, the relay X1 (72) is excited and the contact X1-1a (73) is closed.This circuit is self-sustained and at the same time as the start of the timer TLR2 (74), the contact X1-b is closed. (75) is opened and the green light GL2 (76) is extinguished and the red light RL2 (78) is lit by CLOSE of contact X1-2a (77) to indicate that it is in the settling period.

As described above, when the water level in the reactors 6 and 10 reaches the high water level 1 (HWL1) 59 or the set time of the timer TLR1 58, the blower 22 is stopped to enter the settling cycle.

If the design and position of the level sensor are properly selected, the time difference between the set time of the timer TLR1 58 and the contact HWL1 59 of the high water level 1 is not a problem.

The discharge pump 20 can be selected from the case where the discharge pump 20 is directly connected to the discharge hose 12 connected to the discharge pipe 305 of the floating discharge machine 11, and the case where the discharge pump 20 is used independently without direct connection. First of all, the case of direct connection will be described.

When the set time (1 hour) of the timer TLR2 74 is reached, the magnet coil MC3 / MC4 83 for the discharge pump is excited by the close of the contact TLR2-a (time limit) 84, and the discharge pump 20 is operated. The contact MC3-1a / MC4-1a (90) is closed and the circuit is self-sustained and the timer TLR3 (91) is activated and the contact MC3-b / MC4-b (92) is opened and the green light GL3 (93) is turned off. On the other hand, the contacts MC3-2a / MC4-2a 94 are closed, and the red light RL3 95 is turned on to indicate that the discharge pump 20 is in operation.

As above, self-holding consisting of CLOSE of contact MC3-1a / MC4-1a (90) excites the timer TLR3 (91) and when the discharge set time (1 hour) is reached, the temporary contact TLR3-b (85) is opened and discharged. The power supply of the magnet coil MC3 / MC4 83 of the pump 20 is cut off, and the contact MC3-1a / MC4-1a 90 is opened to cut off the power supply of the timer TLR3 91. Therefore, the contact TLR3-a (time limit) 55 is closed and the blower 22 is operated again.

Next, the discharge pump 20 is independently installed in the sump wall 18 and automatically operated according to the water level of the sump wall 18, that is, the low water level LWL 500, the high water level HWL 501, and the high water level TWL 502. The discharge valve uses the principle of siphon and installs the electric valve 19 at the distal end of the discharge hose 12 to turn on or off the power of the valve actuator 19. Discharge or discontinue discharge by opening and closing.

On the other hand, the CLOSE of the timer time contact TLR2-a (84) excites the relay XC (88) so that the XC-1a (90) contact is closed, and the circuit is self-holding, and at the same time the timer TLR3 (91) starts to operate, the contact XC-b Is opened, the green light GL3 (93) is turned off, the contact XC-3a (81) is closed, and when the current flows through ATo 82, the actuator of the electric valve 19, the electric valve 19 is opened to discharge. At the same time, the contact XC-2a 94 is closed and the red light RL3 95 is turned on to indicate that the symbolic water is being discharged through the electric valve 19.

Self-maintenance of the discharge circuit above, that is, CLOSE of contact XC-1a (90) activates timer TLR3 (91), but when the set time comes, time contact TLR3-b (85) is opened and relay XC (88) and timer TLR3 ( The power supply of 91 is cut off and the contact XC-1b (79) returns and closes, and a current flows through the actuator ATOSE (80) for the actuator CLOSE of the electric valve 19 to close the electric valve 19, and at the same time, the contact The TLR3-a (time limit) 55 is closed and the blower 22 is operated again.

On the other hand, while the discharge pump 20 directly connected to the floating discharger 11 is being operated or the discharge electric valve 19 is opened, the water level in the reaction vessel is lowered while the supernatant water is being discharged. When 86 is OPEN, the power supply of the magnet coils MC3 / MC4 83 and relay XC 88 is cut off and the discharge pump 20 is stopped or the contact XC-3a 81 is OPEN while the contact XC-1b 79 is closed and the voltage is applied to the actuator ATC 80 for closing of the electric valve 19, and the electric valve 19 is closed.

In addition, when the blower 22 is stopped by the CLOSE of the contact HWL1 59 of the high water level 1, the discharge starts after the settling period has elapsed, and the water level in the reactors 6 and 10 is gradually lowered. When passing through 60, the contact HWL2 (60) is opened to cut off the power supply of the relay XA (61), and the contact XA-1a (62) is opened to release the self-holding of the relay XA (61) circuit and return to the original state. do.

If at any time during operation the water level rises due to a mistake or accident and the high water level contact TWL 96 or the boundary water level contact AWL 102 is CLOSEd, the excitation of the relays X2 (98), X3 (104) and XC (88) causes X2-. 1a (87) or X3-1a (89) is closed and a voltage is applied to the discharge pump magnet coil MC3 / MC4 (83) to move the discharge pump 20 or to close to the contact XC-3a (81) ATo (82). ), The level is lowered to the OPEN of the electric valve 19.

In addition, the CLOSE of the contact X3-2a 106 sounds the BUZZER 107 and lights up the boundary level warning light ALML 108 to warn the manager. The CLOSE of the contact X2-3a (100) turns on the highest level indicator TOPL 101 to warn that the level is at the highest level.

When the water level reaches the high water level 2 (HWL2) 60 by the discharge, the contact HWL2 (60) is opened and the power of the relay X2 (98) is cut off, and the discharge pump 20 is stopped by opening the X2-1a (87). The highest level indicator TOPL 101 is turned off to the OPEN of the contact X2-2a (100), and the BUZZER 107 and the boundary level warning lamp ALML 108 are also turned off to return to normal.

In the present invention operating as described in detail above, the effects obtained by the representative of the disclosed design is summarized as follows.

1. Everything is processed in a single tank without the complicated facilities of inflow control tanks, primary and secondary settling tanks, aeration tanks, thickening tanks, anaerobic digestion tanks, dehydration units and return sludge circuits. Therefore, the required area and construction cost for the wastewater treatment plant are about half and a quarter respectively compared to the conventional one.

2. Because of the simple device, the operation and maintenance cost (including operation cost and power cost) is only about 25% compared to the conventional one.

3. The conventional F / M ratio is usually 0.2 to 0.5 and the organic removal rate is limited to 90%, whereas the system has a small amount of activated sludge which is very sedimentable due to the low F / M ratio of long-term aeration (0.05 to 0.2). Because of the formation and the strange function of the floating discharger 11, the organic matter is removed more than 95% can maintain the BOD concentration of the effluent to 20ppm or less.

4. At the F / M ratio of 0.05 to 0.2 and MLSS of 2,000 to 6,000ppm, the treatment efficiency of this system is very high, and the waste sludge is more stable than the conventional one, and its production is much less than one fifth of the conventional one. This can greatly reduce the cost of waste sludge treatment.

5. Low BOD load due to long-term aeration is the most suitable method for wastewater treatment in residential complexes and restaurants since it is very flexible in changing the flow rate and BOD concentration.

6. Nitrogen is rarely removed in the conventional system, but the denitrification process of this system removes more than 95% of nitrogen and the corresponding amount of phosphorus, so that the inflow of streams is not likely to cause eutrophication of the streams, and hydrogen ions in the wastewater. (H ⁺ ) is extracted and eventually generates about 3.6 mg of calcium carbonate alkalinity (alkalinity as CaCO ₃ ) per mg of nitrate (NO ₃ ), a desirable phenomenon such as alkalinity recovery occurs.

7. Due to the intermittent aeration, not only the total oxygen supply and power costs are reduced, but also the oxygen supply from the outside is somewhat reduced due to the oxygen produced during the denitrification process.

8. The tapered aeration method reduces the initial investment and operating costs because the total oxygen supply is smaller than that of the general uniform aeration method.

9. Since the removal rate of nitrogen and phosphorus is very high and odor is not detected in the process, and the exhaust pump and blower are installed at 2 to 3m below the ground, there is almost no noise and vibration, so it is possible to construct in the middle of the city or housing complex. It is an environmentally friendly wastewater treatment system that cannot detect odors in water, ie runoff.

10. Since there are no chemicals or other additives, the operation of the sequence control panel 150 is possible for three to six months of automatic operation, and the operation cost can be controlled by one operator even in a large treatment facility. Compared with this, it can save more than 70%.

Claims (12)

An inlet chamber for equalizing the BOD concentration of the influent wastewater and allowing the influent wastewater to flow into the first reactor via the influent reservoir plate at a flow rate below a certain flow rate; A first reactor allowing the wastewater introduced from the inlet chamber to flow into the second reactor causing a high rate of nitrogen and phosphorus removal through the aeration tank reservoir to maintain a constant flow rate after the abandonment or aeration of the wastewater; A second reactor for intermittently discharging waste sludge produced in the aeration period and making the denitrification process progress to a semi-anaerobic state in the aeration period; Pump chambers / sump wells for discharging supernatant water by direct control of pumps or control of electric valves using the siphon principle; And A forged continuous inlet and long-term tapered aeration intermittent discharge wastewater treatment system, comprising a blower chamber for blowing air to an acid machine by a blower. The forging continuous inlet and long term tapered intermittent wastewater treatment system according to claim 1, wherein the first reactor and the second reactor are partitioned by aeration tank reservoir and aeration tank opening is provided at a lower end thereof. The forged continuous inflow and long-term tapered aeration intermittent discharge wastewater treatment system according to claim 1, wherein an inflow pipe is installed inside the inflow chamber. The forged continuous inflow and long-term tapered aeration intermittent discharge wastewater treatment system according to claim 1, wherein the outlet level of the inflow water is located below the low water level of the entire reaction tank. The forged continuous inlet and long term tapered intermittent wastewater treatment system according to claim 1, wherein the influent reservoir plate is located at least 1m downstream of the inlet chamber outer wall. The forged continuous inlet and long term tapered intermittent discharge wastewater treatment system according to claim 1, wherein the influent water storage plate is provided with an opening at an upper portion of HWL1. The forged continuous inflow and long term tapered intermittent discharge wastewater treatment system according to claim 1, wherein an amount of diffuser suitable for a taper is placed at the bottom of the influent chamber and the entire reaction tank. The forged continuous inlet and long term tapered intermittent wastewater treatment system according to claim 1, comprising a float discharger floating on the water surface in the middle of the second reactor. 9. The forging continuous inlet and long term tapered intermittent discharge wastewater treatment system according to claim 8, further comprising an air tank for maintaining a buoyancy suitable for fixing the floating discharger at a predetermined level. 9. The forged continuous inlet and long term tapered intermittent wastewater treatment system according to claim 8, wherein the floating discharger is provided with a lid valve for withdrawing water from the clearest portion of the symbolic water. 9. The forging continuous inlet and long term tapered intermittent wastewater treatment system according to claim 8, wherein the floating discharger can be additionally installed in parallel as necessary. The forged continuous inflow and long term tapered intermittent wastewater treatment system according to claim 10, wherein the floating discharger is preferably installed to discharge and discharge 20cm to 30cm of subsurface water.