JP2926380B2 - Operating method of activated sludge treatment equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of operating an activated sludge treatment apparatus for treating organic wastewater such as industrial wastewater and domestic wastewater.

[0002]

2. Description of the Related Art Conventionally, as this type of activated sludge treatment method, as shown in FIG. 6, a tank a is divided into a first tank and a second tank in the middle.
A large number of SL disks b provided in these tanks a are rotated at a constant speed, and a sewage introduction pipe c and a treatment liquid outflow pipe d are connected to a predetermined portion of each tank a, and one of the first and second tanks is connected. In the above process, the generated sludge is attached to and propagated on the SL disk b while inflowing sewage from the sewage introduction pipe c, and the processing liquid is diluted with the processing liquid until the generated sludge reaches a limit thickness that does not separate on the SL disk b. When the wastewater flows out of the treatment liquid outflow pipe d and reaches the limit thickness, the inflow of wastewater from the wastewater introduction pipe c is stopped, and the wastewater is drained in the other tank while the one tank is performing wastewater treatment. In a state in which the waste water from the introduction pipe c is stopped, co-eating of the generated sludge of the limit thickness that does not peel off on the SL disk b is performed, and these are alternately repeated in the first and second tanks. Activated sludge treatment method is known No. flat 3-75235).

[0003] The structure of the SL disk is formed by crimping synthetic fibers, especially plastic fibers, and orienting them in a bulky manner, and firmly fixing the intersections and the periphery thereof with a binder to form a disk having a large porosity. It was done.

[0004] Here, S in SL means Synthetic.
fiber (synthetic fiber), and L is an abbreviation for Lock.

[0005]

However, according to the above-mentioned conventional activated sludge treatment method, the SL for adhering and growing the produced sludge is used.
In order to increase the amount of dissolved oxygen in the processing solution, complicated equipment such as a driving device for rotating the SL disk at a constant speed is required, and the processing water due to the rotation is required. There is a problem that the generated sludge may be separated from the SL disk due to friction with the sludge and may be deposited as excess sludge on the bottom of the tank.

An object of the present invention is to solve the above-mentioned problems and to provide a method of operating an activated sludge treatment apparatus in which generated sludge is not likely to be separated and deposited due to friction with a treatment liquid.

[0007]

In order to achieve the above object, the present invention provides a first processing tank containing a liquid to be processed containing dissolved organic matter, which flows in from the outside and whose level gradually rises from below; The liquid to be processed expanded in the first processing tank flows from an opening provided in an upper part of the first processing tank, and the liquid to be processed containing the liquid to be processed whose liquid level gradually rises from below is stored. A second processing tank arranged side by side in one processing tank, and the second processing tank slightly below the opening to discharge the liquid to be processed expanded in the second processing tank to the outside An outflow hole opened in the outer wall of the SL, an SL plate disposed in each of the processing tanks, and attached to a microorganism group as activated sludge generated by oxidizing the dissolved organic matter, and a lower portion in each of the processing tanks. An activated sludge treatment device characterized by comprising an aeration device provided,
The method for operating an activated sludge treatment apparatus of the type in which a liquid to be treated containing dissolved organic matter which has flowed into the first treatment tank is treated, then flows into the second treatment tank, is treated again, and clean water is discharged from an outlet hole. And stopping the flow of the liquid to be treated into the first treatment tank when the microorganisms as the activated sludge of the liquid to be treated attached to the SL plate of the first treatment tank have grown to approximately the critical point. And shutting off the supply of dissolved organic matter contained in the liquid to be treated to the microorganism group as the activated sludge, and reducing or substantially eliminating the activated sludge by oxidizing the activated sludge through the aeration device. Treating solution
The cleaning water is intermittently discharged from an outlet of the second processing tank by flowing into the processing tank.

[0008]

In the method for operating the activated sludge treatment apparatus according to the first aspect, the liquid to be treated containing dissolved organic matter which has flowed into the first treatment tank is treated, then flows into the second treatment tank, and is again treated and discharged. In the operating method of the activated sludge treatment apparatus of the type in which clean water flows out of the hole, when the activated sludge microorganisms of the liquid to be treated that adhere to the SL plate of the first treatment tank grow until reaching a substantially critical point, Stopping the flow of the liquid to be treated into the first treatment tank, and cutting off the supply of the dissolved organic matter contained in the liquid to be treated to the microorganism group as the activated sludge,
After the activated sludge is reduced or substantially eliminated by oxidizing through the aeration device, the liquid to be treated flows into the first treatment tank again, and the clean water is intermittently discharged from the outlet of the second treatment tank. Spilled out.

Thus, there is no possibility that the generated sludge will be separated from the SL plate due to friction with the liquid to be processed and will be deposited on the bottom of each processing tank.

[0010] In the method for operating the activated sludge treatment apparatus according to claim 2, a plurality of the first treatment tanks are provided adjacent to the second treatment tank, and the first treatment tank is provided with a plurality of first treatment tanks. In one treatment tank, microorganisms as activated sludge of the liquid to be treated adhere to the SL plate until they reach a substantially critical point,
In the remaining first treatment tank, the inflow of the liquid to be treated is stopped, and the supply of the dissolved organic matter contained in the liquid to be treated to the microorganism group as the activated sludge is cut off. The water is reduced or substantially eliminated by oxidizing the water, and the cleaning water is continuously discharged from the outlet of the second processing tank by alternately performing these.

Thus, the working efficiency of cleaning the liquid to be treated is greatly improved.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS.

Reference numeral 1 denotes a main body of the activated sludge treatment apparatus used in the present embodiment. The main body 1 is a semi-closed substantially rectangular parallelepiped covered housing, and the space on both sides in the longitudinal direction thereof is subjected to a first treatment. Tanks 1a, 1a, and the first processing tanks 1a,
The central space located between 1a is defined as a second processing tank 1b,
Inside the left and right outer walls in the longitudinal direction of each of the processing tanks 1a, 1a and 1b, a plurality of U-shaped cross-sectional grooves for inserting and locking an SL plate 3 described below from above are provided. 1c are formed, and a through hole 1d is provided below one of the outer walls in the longitudinal direction of each of the processing tanks 1a, 1a, 1b, and the longitudinal direction of the second processing tank 1b. Outflow holes 1e through which the liquid A to be processed flows out of the second processing tank 1b are provided in an upper portion of one of the outer walls, and left and right sides of each of the first processing tanks 1a and 1a in the lateral direction are provided. Through holes 1f, 1f for allowing the liquid to be treated A to flow into the first processing tanks 1a, 1a are provided in an upper portion of the outer wall of the first processing tank 1a.

Reference numerals 2 and 2 denote partition walls for partitioning the first processing tanks 1a and 1a from the second processing tank 1b. Outflow holes of the second processing tank 1b are provided above the partition walls 2 and 2. 1e, the liquid A to be treated is placed in the first treatment tank 1
a, a rectangular opening 2e for flowing into the second processing tank 1b from the first processing tank 1b is provided.

Reference numeral 3 denotes a substantially rectangular SL plate. The SL plate 3 is disposed vertically above the processing tanks 1a, 1a and 1b in the main body 1 when the outer lid of the main body 1 is removed. Inserted along the groove 1c and arranged at substantially equal intervals.

Reference numerals 4 and 4 denote valves. The valves 4 and 4 are interposed in a pipe 5 for inflow of the liquid A to be treated, which communicates with the through holes 1f and 1f of the first treatment tanks 1a and 1a. .

Reference numeral 6 denotes an aeration device. The aeration device 6 is connected in parallel to the floor of each of the processing tanks 1a, 1a and 1b and has a plurality of air ejection holes 6c and communicates with the pipes 6b. An external pipe 6a is connected to an air supply device such as a compressor (not shown) through the through hole 1d.

Reference numeral 7 denotes a pipe communicating with the outflow hole 1e through which the liquid to be treated A flows out of the second processing tank 1b, 8 denotes a bolt for joining the outer lid of the main body 1 to the main body 1, and 9 denotes a pipe. The holes for air B and the like provided in the outer lid of the main body 1 are shown.

As described above, S of the SL plate is Syn.
thetic fiber (synthetic fiber) and L is Loc
This is an abbreviation for k (adhesion), and the SL plate is a synthetic fiber, particularly a plastic fiber, which is crimped and oriented in a bulky manner, and its intersection and periphery are firmly adhered with a binder to increase the space ratio. It is formed on a plate.

Next, a method of operating the activated sludge treatment apparatus of the present invention using the activated sludge treatment apparatus will be described.

First, the valve 4 on the left side is opened to feed the water A to be treated into the first processing tank 1a on the left, and a compressor or the like (not shown) is operated to supply air into the first processing tank 1a. Countless small air bubbles B are sent through the ejection holes 6c.

The liquid level C of the liquid A gradually flows up to the position shown by the solid line in FIG. 2 and further flows into the second processing tank 1b through the opening 2a provided in the partition 2. The liquid A to be processed expanded in the second processing tank 1b is in the second position because the outlet 1e is slightly below the opening 2a.
Without flowing back from the processing tank 1b to the first processing tank 1a, it flows out through the outlet 1e.

At this time, in the first processing tank 1a, the dissolved organic matter in the liquid A to be processed is pumped by the bubbling air 6 to dissolve dissolved oxygen in the liquid A to be processed whose dissolved rate is increased. A chemical reaction occurs, and microorganism groups D as activated sludge are generated. These microorganism groups D adhere to the fibrous tissue of the SL plate 3 having a large space ratio and multiply as shown by the broken line in FIG.

The liquid A to be treated with the dissolved organic matter in the first treatment tank 1a is substantially in inverse proportion to the growth of the microorganism group D.
The concentration of the dissolved organic matter in the liquid to be treated A further decreases due to the decrease in the concentration of the dissolved organic matter, and the concentration of the microorganisms D adheres to the plate-like body 3 in the second treatment tank 1b. Clean water flows out through the hole 1e.

Next, the opening of the left valve 4 is delayed with a lapse of time, and the right valve 4 is opened to reproduce the same operation and state as described above.

By the way, the microorganism group D which continues to multiply reaches a critical point at which the microorganism group D can no longer adhere to the plate-like body 3. When the critical point is exceeded, the microorganism group D stops growing, and the microorganism group D stops growing. Is not only peeled off from the plate-like body 3 but also the concentration of the dissolved organic matter in the liquid to be treated A sharply rises, and the liquid to be treated A which is not purified may flow out through the outflow holes 1e. The liquid level C of the liquid A to be treated is lowered from the solid line in FIG. 2 to the position shown by the broken line in FIG. The liquid A does not flow out.

At this time, the first processing tank 1a on the left
Within, the supply of the dissolved organic matter as feed stops, so that the cells in the group of microorganisms D undergo a chemical reaction with the dissolved oxygen and change into a gasified mixture. It decreases or almost disappears.

The left valve 4 reopened in the left first treatment tank 1a having the SL plate 3 in which the activated sludge as the microorganism group D has disappeared and the adsorptivity has been restored.
The liquid to be treated A is injected through the above.

On the other hand, after that, the right first processing tank 1a reaches the critical point later than the critical point occurring in the left first processing tank 1a.
The same operation and state as described above are reproduced in the processing tank 1a.

Thus, by alternately reproducing the above-described operation and state of the first treatment tanks 1a and 1a, the clean water is continuously discharged to the outlet hole 1e without taking out the activated sludge D as the microorganisms. Can flow out to the outside.

When the plate 3 has deteriorated, the bolt 8 can be removed and the outer lid of the main body 1 can be removed and replaced. However, the plate 3 in the second processing tank 1b is not replaced. ,
Activated sludge D which adheres and multiplies because the dissolved organic matter in the liquid to be treated A is almost removed in the first treatment tank 1a.
Can be used for a long time because the amount is small.

Further, in the above embodiment, both the first processing tanks 1a and 1a and the second processing tank 1b,
The treatment liquid A of the dissolved organic matter is contained in the treatment tanks 1a and 1a.
A biosensor for measuring the concentration in the biosensor is provided, and the control device inputs a detection signal from the biosensor, and when the detection signal is equal to or less than a set value, the valves 4, 4
By opening and closing individually, automatic operation becomes possible.

As another embodiment, as shown in FIGS. 4 and 5, the first processing tank 1a is juxtaposed so as to be surrounded by the second processing tank 1b, and the valve 4 with a time delay is opened. It is also possible to improve the working efficiency by shortening the plug interval.

[0034]

As described above, according to the present invention, the sludge generated by the friction with the liquid to be treated does not peel off from the SL plate and accumulates at the bottom of each of the treatment tanks, and has conventionally been required. Since a driving device is not required, the equipment can be simplified and the operating cost can be reduced. Further, since the water to be treated is purified over the two stages of the treatment tank, the load on the plate-like body in each tank is substantially reduced. It has the effect of being reduced.

[Brief description of the drawings]

FIG. 1 is a partially cutaway plan view of one embodiment of the present invention.

FIG. 2 is a front view, partly cut away.

FIG. 3 is a sectional plan view taken along the line III-III of FIG. 2;

FIG. 4 is a cutaway plan view of another embodiment of the present invention.

FIG. 5 is a cutaway plan view of another embodiment of the present invention.

FIG. 6 is a perspective view of a conventional device.

[Explanation of symbols]

 1a 1st processing tank 1b 2nd processing tank 1e Outflow hole 2a Opening point 3 SL plate 4 Valve 6 Aerator A Liquid to be treated B Air C Liquid level D Activated sludge

Claims (2)

(57) [Claims] 1. A first processing tank containing a liquid to be processed containing dissolved organic matter which flows in from the outside and whose liquid level gradually rises from below, and the liquid to be processed expanded in the first processing tank Flows from an opening provided in an upper portion of the first processing tank, and a second processing tank arranged in parallel with the first processing tank containing the liquid to be processed whose level gradually rises from below, An outflow hole formed in an outer wall of the second processing tank slightly below the opening to allow the liquid to be processed expanded in the second processing tank to flow outward; Activated sludge, comprising: an SL plate disposed in a treatment tank and attached to a microorganism group as an activated sludge generated by oxidizing the dissolved organic matter; and an aeration device provided at a lower portion in each of the treatment tanks. A treatment apparatus containing dissolved organic matter flowing into the first treatment tank;
After treating the solution, it flows into the second treatment tank and is treated again
Activated sludge treatment system that discharges clean water from the outlet
In the operation method of the above, the adhering to the SL plate of the first processing tank
Microorganisms, which are activated sludge of the liquid to be treated, reach a critical point
When the liquid to be processed is transferred to the first processing tank
To stop the flow of dissolved organic matter contained in the liquid to be treated.
And the supply of microorganisms to the activated sludge
Oxidizing the activated sludge through the aeration device
The liquid to be treated is again reduced or almost eliminated by
Outflow hole of the second processing tank after flowing into the first processing tank
Activated water, characterized by intermittent discharge of clean water from
Operation method of mud treatment equipment. 2. The method according to claim 1 , wherein a plurality of said first processing tanks are connected to said second processing tank.
Is provided adjacent to the first processing tank.
In the treatment tank, the activated sludge of the liquid to be treated
The organisms are allowed to attach until they reach a critical point, and
Stop the flow of the liquid to be treated in the first treatment tank
The activated sludge of dissolved organic matter contained in the liquid to be treated
Shut off the supply to the microbial community and pass the activated sludge to the exposing device
Is reduced or almost annihilated by oxidation through
By alternately performing these, the outflow holes of the second processing tank
The method for operating an activated sludge treatment apparatus according to claim 1, wherein clean water is continuously flowed out of the apparatus .