JPH0152078B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for treating human waste wastewater, which targets highly concentrated organic wastewater containing a large amount of nitrogen, such as human waste and digestive desorbed fluid.

Generally, when treating human waste such as highly concentrated organic wastewater, it is necessary not only to simply decompose and remove organic matter, but also to remove nitrogen and the like at the same time.

This invention was made in view of the above circumstances,
A human waste system that allows highly concentrated organic waste liquid such as human waste containing a large amount of nitrogen to continuously flow into a single intermittent aeration tank, while simultaneously decomposing and removing organic matter in the inflowing waste liquid and efficiently denitrifying it. The purpose is to provide a method for treating sewage.

Hereinafter, preferred embodiments of the present invention will be described based on the drawings.

FIG. 1 is a flow sheet showing the method for treating human waste wastewater according to the present invention, in which wastewater such as human waste first flows into an intermittent aeration tank, undergoes aeration treatment in a first inflow chamber, and then undergoes aeration treatment in a second inflow chamber. After the anaerobic treatment, stirring, aeration, precipitation, and supernatant liquid discharge are performed in the main aeration chamber of this intermittent aeration tank.

At this time, the wastewater is continuously flowed into the first inlet chamber without being restricted by the treatment cycle in the main aeration chamber.

The main aeration chamber of the intermittent aeration tank is controlled, for example, by a timer or the like, to repeat the steps of stirring, aeration, precipitation, and supernatant liquid discharge for a predetermined period of time.

Denitrification occurs in the stirring process, oxidation of organic matter and nitrification of nitrogen in the wastewater occurs in the aeration process, and the sludge is sedimented and separated in the next precipitation process, resulting in purified supernatant liquid. It is discharged during the discharge process.

Since the intermittent aeration tank allows sewage to continuously flow in without being restricted as described above, it also functions as a sewage storage tank in addition to the above-mentioned process functions, and the continuously flowing sewage can be treated without any problem.

The supernatant liquid purified in the intermittent aeration tank in the above manner is led to the nitrification step as a subsequent treatment step, and is aerated in this nitrification step. By this aeration treatment, nitrification of the nitrogen content is almost completely performed.

The nitrified wastewater is then led to a denitrification process, which is the next post-processing process, and undergoes denitrification treatment. An organic substance such as methanol may be added to this denitrification step as needed, but this addition is not essential.

In the nitrification step and denitrification step in the latter stage treatment step, since there is an intermittent aeration tank at the front stage, the inflow is intermittent. In other words, sewage flows into the intermittent aeration tank in the previous stage only during the supernatant liquid discharge process.

Therefore, the nitrification step and the denitrification step are performed in one tank, and since there is no inflow of waste water during these steps, complete nitrification and denitrification can be achieved.

Furthermore, it is preferable to perform precipitation treatment in this nitrification/denitrification tank and then discharge the supernatant liquid. It is preferable that the control of such a subsequent treatment step be performed using the same signal so as to be synchronized with the control of the intermittent aeration tank in the previous stage.

FIG. 2 shows an intermittent aeration tank applied to carry out the method for treating human waste wastewater of the present invention.

This intermittent aeration tank 1 consists of a single tank having a substantially rectangular shape, and inside the tank there is a partition plate 2 and a barrier 3.
are housed and arranged at predetermined intervals, respectively, and the first inflow chamber 4, the second inflow chamber 5, and the main air chamber 6 are partitioned and formed by these.

Here, the baffle 2 is opened at the bottom so that the first inflow chamber 4 and the second inflow chamber 5 communicate with each other at the bottom side, and sewage such as raw human urine flows from the inflow side 1a of the intermittent aeration tank 1. The above first method for continuous inflow of
The inflow chamber 4 is partitioned.

Further, the barrier 3 has a second inflow chamber 5 between the baffle 2 and the baffle 2 on the opposite side of the second inflow chamber 5 at a predetermined distance from the baffle 2, and a second inflow chamber 5 between the baffle 2 and the intermittent air tank 1. A main air chamber 6 is partitioned and formed on the discharge end 1b side.

The upper end of the barrier 3 is located near the low water levels L, W, and L in the intermittent aeration tank 1, and has a height lower than that of the buffer 2.

A decanter 7 for discharging the supernatant liquid is provided in the upper part of the main aeration chamber 6 so as to be movable up and down in accordance with fluctuations in the liquid level in the intermittent aeration tank 1.

The decanter 7 is attached to a rotatable shaft tube 7b via a tube through which a wear tube 7a descends so that the decanter 7 can move up and down. This shaft pipe 7b passes through the tank wall on the discharge end 1b side of the intermittent aeration tank 1 and communicates with an external subsequent treatment tank (nitrification/denitrification tank 13 in FIG. 5, which will be described later).

The main air chamber 6 is connected to the first inlet chamber 4 by a liquid return pipe 9 having a pump P.

Therefore, the pump P supplies the indoor liquid during the aeration process to the main aeration chamber 6 through the liquid return pipe 9.
It serves the function of returning to the inflow chamber 4.

This return improves the decomposition and nitrification efficiency of highly concentrated organic matter in wastewater. Near the bottom of the intermittent aeration tank 1, there are a plurality of nozzles 8a to 8.
c is placed. In the first inflow chamber, the nozzle 8a is connected to an air supply pipe or a pump (not shown) capable of injecting air or air and liquid so as to perform aeration treatment for decomposing and nitrifying organic matter in the liquid. )It is connected to the.

In the second inflow chamber 5, in order to perform anaerobic treatment for denitrification, the nozzle 8b is equipped with a unique pump disposed in the second inflow chamber 5, which is capable of stirring the indoor liquid. (not shown) or to a jet aeration device (not shown).

In the main aeration chamber 6, the nozzle 8c is connected to an air supply pipe, a pump, and a jet aeration device so that stirring, aeration, precipitation, and discharge can be repeated. There is.

In the above, the first inflow chamber 4 aerates the wastewater while continuously flowing into the first inlet chamber 4, thereby decomposing and nitrifying organic matter. This nitrifying liquid then flows into the second inlet chamber 5, where, for example, a pump (not shown) arranged in the second inlet chamber 5 is used.
In addition, the second inlet chamber 5 can create an anaerobic state by circulating and stirring the indoor liquid by a jet aeration device (not shown), thereby promoting the denitrification reaction.

Therefore, the water in the first inflow chamber 4 in the intermittent aeration tank 1 and the main aeration chamber 6 during the aeration process is atomized by the air jetted from the aeration nozzle 8c, and the water is During the stirring process in the inflow chamber 5 and the main aeration chamber 6, the denitrification process is performed by stirring the indoor liquids in the second inflow chamber 5 and the main aeration chamber 6, respectively.

Therefore, in the intermittent aeration tank 1, the wastewater that continuously flows into the first inflow chamber 4 is nitrified by the aeration treatment in the first inflow chamber 4, and the nitrified liquid flows into the second inflow chamber 5. However, in this second inflow chamber 5, denitrification treatment is effectively performed under anaerobic conditions. Then,
After this denitrification process, the indoor liquid in the second inflow chamber 5 overflows the upper end of the barrier 3 and flows into the main air chamber 6. Denitrification is performed in the stirring process in the main aeration chamber 6, and BOD removal and nitrification are performed in the aeration process.

Here, the agitation in the second inflow chamber 5 is performed when the main aeration chamber 6 is in the aeration and agitation process so as not to adversely affect the processing in the main aeration chamber 6.

In the main air chamber 6 like this example, the low water level L,
After the indoor liquid is circulated at W and L for a certain period of time and stirred, aeration treatment is started, and then aeration is stopped near the middle water level M, W, and L, where the inflow water has increased, and precipitation treatment is performed. and introduce inflow water up to high water levels H, W, and L. Thereafter, the decanter 7 descends from the high water levels H, W, L to the low water levels L, W, L, and the decanter discharges the supernatant liquid.
Operation of the decanter 7 and the aeration nozzle 8c
The operation of a system air supply source (not shown) is controlled by, for example, a timer.

Note that each step of the above-mentioned stirring, aeration, precipitation, and supernatant liquid discharge can also be controlled by a timer.
In this case, a certain margin of liquid height is required above the intermittent air tank 1. When controlling the treatment cycle with a timer, for example, as shown in Figure 3, one cycle is 6 hours, with stirring for 0.5 hours, aeration treatment for 4 hours, precipitation treatment for 1 hour, and supernatant liquid discharge treatment.
Controlled to repeat each step for 0.5 hours.

The liquid in the main aeration chamber 6 is returned to the first inflow chamber 4 via the liquid return pipe 9 by the pump P as described above, and is effectively aerated through the aeration process in the first inflow chamber 4. Nitrification takes place. This nitrified liquid then flows into the second inflow chamber 5 and undergoes denitrification treatment, and then is further subjected to nitrification and denitrification treatment in the main aeration chamber 6, and the supernatant liquid in the main aeration chamber 6 after the treatment is discharged from the decanter 7. This discharged liquid is introduced into the nitrification/denitrification tank 13 shown in FIG. 5, which is a subsequent treatment step.

In this nitrification/denitrification tank 13, the water level in the tank rises from low water levels L, W, L to high water levels H, W, L by introducing the discharged liquid from the main evaporation chamber 6 as described above.

The nitrification/denitrification tank 13 is operated according to the treatment cycle in the intermittent aeration tank 1 in the previous stage: aeration (nitrification) → stirring (denitrification) → precipitation → supernatant liquid discharge →
Each step of inflowing the supernatant liquid from the main aeration chamber 6 is repeated. Here, during the supernatant liquid discharge process of the intermittent aeration tank 1, that is, from the main aeration chamber 6 to the nitrification/denitrification tank 1.
Before the supernatant fluid inflow into the nitrification/denitrification tank 13 (inflow process) is started, the supernatant fluid discharge from the nitrification/denitrification tank 13 must have already been completed, and during the above inflow process, the may be started, this aeration and agitation being carried out by jet aeration nozzles 12. 9a is a liquid supply pipe.

FIG. 4A is a plan view of an intermittent aeration tank according to another embodiment of the present invention, and FIG. 4B is an enlarged sectional view of a jet aeration nozzle.

The intermittent aeration tank 1 shown in FIG. The first inlet chamber 4, the second inlet chamber 5, and the main air chamber 6 each have jet aeration nozzles 12 housed therein.

This jet aeration nozzle 12 and the jet aeration nozzle 12 in the nitrification/denitrification tank 13 have the same construction, as shown in FIG. 4B. and. This nozzle is connected to a pump P which is connected to the gas-liquid supply pipe 9b and the liquid supply pipe 9c in FIG. 4A. Here, the gas-liquid supply pipe 9b of the second inflow chamber 5 supplies only liquid. Further, 9 is a liquid return pipe, through which the indoor liquid in the main air chamber 6 can be returned to the first inflow chamber 4 via the pump P.

Such a jet aeration nozzle 12 is
By operating the pump P, the indoor liquid from the liquid supply pipe 9c is mixed with air, and a gas-liquid mixture is injected into each room to perform aeration processing, and the air is stopped. It has the function of injecting only the liquid in each room from the liquid supply pipe 9c into each room to perform a stirring process (denitrification process).

Therefore, in this embodiment, by injecting air from the jet aeration nozzles 12 of the first inflow chamber 4 and the main air chamber 6, the liquids in these chambers are exposed to heat as in the previous embodiment. It is treated with air.

Further, the jet aeration 12 of the second inflow chamber 5 injects only the indoor liquid in the second inflow chamber 5, whereby the indoor liquid in the second inflow chamber 5 is circulated and agitated, thereby causing the above-mentioned The second inflow chamber 5 becomes anaerobic and the denitrification reaction is promoted.

Also, the main ventilation chamber 6 in the intermittent ventilation tank 1
The aeration treatment effect is good, and one jet aeration nozzle 12 can be used for the aeration treatment and liquid stirring in an anaerobic state, which is very economical.

As described above, according to the present invention, although the intermittent aeration tank is a combination of the intermittent aeration tank in the former stage and the nitrification/denitrification tank in the latter stage, the intermittent aeration tank has a first inflow chamber and a second inflow chamber in the tank. Each of the chamber and the main aeration chamber has a single tank structure with partitions formed, and while sewage is continuously flowing into the first inflow chamber, the inflow sewage is aerated in the first inflow chamber to remove organic matter. is decomposed and nitrified, and then the nitrified liquid is caused to flow into the second inflow chamber, and the second inflow chamber is brought into an anaerobic state for denitrification, and then the supernatant liquid is transferred to the second inflow chamber. The liquid flows into the main aeration chamber, and the main aeration chamber repeats stirring, aeration, precipitation, and discharge.Moreover, the liquid in the main aeration chamber is returned to the first inflow chamber. The decomposition and nitrification of organic matter is promoted in the inflow chamber, and the second inflow chamber into which the indoor liquid of the first inflow chamber flows is partitioned from the first inflow chamber and the main air chamber. In the second inflow chamber, an anaerobic state can be easily obtained by circulating and stirring the indoor liquid, which promotes the denitrification reaction and performs efficient denitrification. Most of the denitrification treatment can be carried out using the single intermittent aeration tank, which does not require a storage tank or the like.

Moreover, when the purified supernatant liquid is discharged from the main aeration chamber in the intermittent aeration tank, the discharged liquid is introduced into the subsequent nitrification/denitrification tank, and further nitrification is performed in the nitrification/denitrification tank. Efficient denitrification treatment can be performed.

In summary, in this invention, most of the BOD and nitrogen are efficiently removed in the intermittent aeration tank at the front stage, so the load of the nitrification/denitrification process is reduced in the nitrification/denitrification tank at the rear stage. The volume of the nitrification/denitrification tank can be reduced, yet a remarkable denitrification effect can be obtained.

[Brief explanation of drawings]

FIG. 1 is a flow sheet showing the method for treating human waste water of the present invention, FIG. 2 is a sectional view showing an embodiment of an intermittent aeration tank applied to the method of treating human waste water of the present invention, and FIG. The figure is a treatment cycle time chart of the present invention, Figure 4A is a schematic plan view showing another embodiment of the intermittent aeration tank, Figure 4B is a sectional view of the jet aeration nozzle, and Figure 5 is a schematic plan view showing another embodiment of the intermittent aeration tank. FIG. 2 is a schematic cross-sectional view of a nitrification/denitrification tank. 1...Intermittent air tank, 2...Batsuful, 3...Barrier,
4...First inflow chamber, 5...Second inflow chamber, 6...Main air chamber, 13...Nitrification/denitrification tank.

Claims (1)

[Claims] 1. A first inlet chamber into which wastewater is continuously introduced;
a second inflow chamber communicating with the inflow chamber on the bottom side;
An intermittent aeration tank configured such that each of the main aeration chambers into which indoor liquid flows from the inflow chamber is partitioned into a single tank, and a purified supernatant liquid discharged from the main aeration chamber of the intermittent aeration tank. a nitrification/denitrification tank into which sewage is introduced, a step of continuously inflowing sewage into the first inflow chamber and aerating the inflow sewage in the first inflow chamber to decompose and nitrify organic matter; A step of causing the liquid to flow into the second inflow chamber and denitrifying it by anaerobic treatment in the second inflow chamber, and a step of transferring the indoor liquid in the second inflow chamber after the denitrification step into the main air chamber. a step of repeating stirring, aeration, precipitation, and discharge in the main aeration chamber; a step of returning the indoor liquid in the main aeration chamber to the first inflow chamber during the aeration step; When the purified supernatant liquid is discharged from the air chamber, the purified supernatant liquid is introduced into the nitrification/denitrification tank, and the purified supernatant liquid is further nitrified in the nitrification/denitrification tank, and the nitrified liquid is subjected to the nitrification process. - A method for treating human waste wastewater, which comprises the step of further denitrifying in a denitrifying tank. 2 Between the first inflow chamber and the second inflow chamber,
The two chambers are partitioned by a buttful which is open at the bottom so as to communicate with each other at the bottom side, and a barrier lower than the buttful is partitioned between the second inflow chamber and the main air chamber, and the upper end of this barrier is connected to the 2. The method for treating night soil wastewater according to claim 1, wherein the indoor liquid in the second inflow chamber overflows and flows into the main ventilation chamber.