JP3278216B2 - Sewage 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 sewage treatment apparatus suitable for pretreatment of organic household wastewater and industrial wastewater in which the amount and quality of wastewater discharged intermittently change in a short time.

[0002]

2. Description of the Related Art One of the assignees of the present invention, Daiwa Sekisho Kogyo Co., Ltd., disclosed in Japanese Patent Application Laid-Open No. 63-158191, the lower end of the treatment tank was separated from the bottom and the upper end was projected above the water surface. An inner cylinder is installed vertically to form an endless water channel between the inner circumference of the treatment tank and the outer circumference of the inner cylinder. Raw water is supplied to the endless water channel by a water supply pipe, and the treated water is treated from inside the inner cylinder. We proposed a sewage treatment device that was drawn out of the tank with a drain pipe. This sewage treatment apparatus is a solid-liquid sedimentation separation apparatus, and is provided with a horizontal jet port at the tip of a water supply pipe that has entered the water of an endless waterway, the raw water being a one-way swirling flow along the endless waterway. , Coarse solids in the raw water are placed on the bottom of the tank below the endless channel,
Is settled at the bottom of the tank below the inside of the inner cylinder.

[0003]

In the above-mentioned prior proposal, the swirling flow of raw water spouted from the lateral outlet at the end of the water supply pipe into the endless water channel reduces kinetic energy only by gravity and friction with the wall surface of the water channel. For this reason, the inside of the tank is disturbed by the swirling flow, and it takes time for the liquid in the tank to stand still, during which time solids deposited on the bottom of the tank are soared or solids are uniformly settled on the bottom of the tank I can't do enough. Furthermore, in order to perform biological treatment in order to obtain high treated water quality, the treated water extracted from the inner cylinder to the outside of the treatment tank must be guided to a separately installed biological treatment tank for treatment, and the installation space is required. This causes problems such as an increase in cost.

[0004]

A first aspect of the present invention relates to a sewage treatment apparatus as a sedimentation / separation apparatus in which the kinetic energy of a swirling flow is rapidly reduced to solve the above-mentioned problems. The lower end is separated upward from the bottom of the tank, and an inner cylinder whose upper end protrudes above the water surface is vertically installed to form an endless water passage between the inner periphery of the treatment tank and the outer periphery of the inner cylinder. Is supplied through a water supply pipe, and the treated water is extracted from the inside of the inner cylinder to the outside of the treatment tank by a drain pipe. Providing two branch jets for feeding and turning in the opposite direction to the water channel, and providing a baffle plate that crosses the endless water channel in the endless water channel at a position directly opposite to the position where the water supply pipe is provided. It is characterized by. Further, claim 2 relates to a sewage treatment apparatus in which sedimentation separation and anaerobic biological treatment are performed in a single tank, wherein the lower end is separated upward from the tank bottom and the upper end is positioned above the water surface inside the treatment tank. An inner cylinder protruding vertically is formed to form an endless water passage between the inner periphery of the treatment tank and the outer periphery of the inner cylinder,
In a sewage treatment apparatus in which raw water is supplied into the endless waterway by a water supply pipe, and treated water is drawn out of the inner cylinder through a drainage pipe to the outside of the treatment tank, the end of the water supply pipe that has entered the water of the endless waterway Two branch jets for supplying raw water to the endless water channel in the opposite direction and turning the water, and obstructing the endless waterway in the endless waterway at a position exactly opposite to the position where the water supply pipe is provided. A plate is provided, a group of carriers to which microorganisms are attached are densely supported inside the inner cylinder, and the group of carriers is hung down from a lower end of the inner cylinder. In the sewage treatment apparatus according to any one of claims 1 and 2, the baffle provided at a position directly opposite to the water supply pipe in the endless waterway is suspended swingably across the endless waterway. Is preferred.

[0005]

1 and 2 show an embodiment of the sewage treatment apparatus according to the first aspect, and FIGS. 3 and 4 show an embodiment of the sewage treatment apparatus of the second aspect. In each of the embodiments, 10 is a processing tank having a bottom,
Reference numeral 11 denotes an inner cylinder which is provided vertically inside the processing tank and has a lower end separated from the tank bottom 10 ′ and an upper end protruding above the water surface, between the inner periphery of the processing tank 10 and the outer periphery of the inner cylinder 11. Endless waterway 12
Are formed. Reference numeral 13 denotes a water supply pipe for supplying raw water (sewage) into the endless water channel 12, reference numeral 15 denotes a drain pipe for extracting treated water from the inside of the inner cylinder 11 to the outside of the treatment tank 10, and treated water in the inner cylinder is a drain pipe. Overflows into the inner cylinder 1
1 and the water level L in the endless water channel 12 are kept constant. The lower end of the inner cylinder 11 is approximately 40 water levels from the tank bottom 10 '.
５０50%.

In the illustrated embodiment, the treatment tank 10 and the inner cylinder 11 are cylindrical and concentrically arranged, so that the endless water channel 12 is annular, but the treatment tank and / or the inner cylinder is a polygonal cylinder. The shape and the elliptical cylinder may be used, and the arrangement of the inner cylinder with respect to the treatment tank may not be concentric as long as the closed endless water channel 12 is formed. In addition, the diameter and depth of the treatment tank 10 and the diameter and length of the inner cylinder 11 are appropriately determined according to the amount of wastewater to be treated, the stagnation time, and the like.

The water supply pipe 13 which has entered the water of the endless water channel 12
Has a T-shaped tip and has two branch jets 14a,
14b. Both ejection ports 14a and 14b are inner cylinder 1
1, the raw water supplied intermittently in the water supply pipe 13 is supplied to the branch outlet 14a,
At 14b, they are split into two, and are jetted in opposite directions from the branch jet ports 14a and 14b into the endless water channel 12 to generate two swirling flows A and B in diametrically opposite directions (FIG. 2, FIG. 2).
4,5).

In the endless water channel 12, a position opposite to the position where the water supply pipe 13 is provided, in this embodiment, the processing tank 10,
Since the inner cylinder 11 is cylindrical, a baffle plate 16 that crosses the endless water channel 12 is provided at a position diametrically opposed to the position of the water supply pipe 13. The upper end of the baffle plate 16 projects upward from the water level L in the endless water channel 12.

As described above, the raw water supplied intermittently through the water supply pipe 13 is divided into approximately two by two oppositely-directed branch jets 14a and 14b provided at the lower end of the pipe 13, and each of the branch jets 14a and 14b is separated. Ejected in the opposite direction from 14b, two swirling flows A and B in opposite directions are generated in the endless channel. As shown in FIG. 5, the swirling flows A and B collide with the respective surfaces of the baffle plate 16 traversing the endless water channel 12 at a position exactly opposite to the water supply pipe 13 and are reversed by the collision. become. Since the baffle plate 16 serves to change the swirling flows A and B into reverse flows A 'and B' in opposite directions, the position of the lower end 16 'or the downward length of the baffle plate is endless. The swirling flows A and B that come while spreading downward in the waterway are determined so that they can collide with each other.

In the sewage treatment apparatus according to the present invention, the two branch jets 14a and 14b provided at the end of the water supply pipe 13 roughly divide the sewage supplied into the endless water channel 12 into two diametrically opposite directions. Two swirling flows A and B are generated. The kinetic energy of each of the bisected swirling flows A and B is smaller than the kinetic energy of one swirling flow that is not bisected. Therefore, the kinetic energy of the two swirling flows A and B is greatly reduced by friction with the wall surface of the endless channel.

Then, the two swirling flows A and B collide with the baffle plate 16 while reducing the kinetic energy, and the reverse flows A
′ And B ′, but the kinetic energy is greatly reduced by the collision with the baffle plate, and the kinetic energy of the reverse flows A ′ and B ′ is greatly attenuated. As a result, sewage is intermittently supplied to the endless water channel 12, and two swirling flows and a reversing flow are generated in the endless water channel. However, the liquid in the water channel quickly stands still and solids ( There is no re-emerging or rising of the accumulated sludge. By the two swirling flows and the reversing flow, the solid matter having a large mass in the sewage is discharged from the tank bottom 1 below the endless water channel 12.
It is uniformly deposited on 0 'and does not deviate.

The baffle plate 16 for changing the swirling flows A and B into the reverse flows A 'and B' in the endless water channel 12 has opposite directions.
The water supply pipe 13 may be fixedly provided at a position directly opposite to the water supply pipe 13. However, it is preferable that the water supply pipe 13 is provided so as to be swingably suspended in water in an endless waterway in a pendulum manner for the reason described later. In each of the illustrated embodiments, the drain pipe 15 also serves to suspend the baffle plate on the end pipe, so that the drain pipe 15 is traversed at the position where the baffle plate 16 is suspended on the endless water channel, and the support member 17 attached to the upper end of the baffle plate is provided. Is fitted to the drain pipe, and the baffle is suspended swingably, but not limited to this, the horizontal axis other than the drain pipe is fixed across the endless waterway,
The baffle may be suspended swingably, or a baffle may be suspended by a hinge on a support fixed across the endless waterway.

As described above, the two branch jets 14a and 14b at the end of the water supply pipe 13 supply the sewage into the endless water channel 12 by roughly dividing it into two, and the two swirling flows A in opposite directions into the water channel. , B, but branch jets 14a, 14b
Since there is a difference in the flow rate of the sewage flowing out of b, the two swirling flows A and B are asymmetric unequal flows. The tendency is that a large amount of sewage such as bathtub drainage is temporarily
It appears remarkably when flowing into 2. When the asymmetric swirling flows A and B collide with the baffle plate 16 in this way, the reverse flows A ′ and B ′ do not become symmetrical reverse flows when the baffle plate is fixed, and the momentum does not increase. A downward flow to the bottom of the tank occurs to maintain the balance of the flow, and the flow in the tank is disrupted. However, when the baffle plate 16 is suspended swingably as described above, the baffle plate 16 is swung to an angle commensurate with the momentum of the asymmetric swirling flows A and B, so that the baffle plate 16 collides with the baffle plate. Reversal flow A
'And B' become almost completely symmetrical flows, the momentum balance is maintained, the downward flow to the tank bottom is suppressed, the braking effect of the flow in the tank is increased, and no disturbance occurs.

As a result, sewage is intermittently supplied to the endless water channel 12 and two swirling flows and a reversing flow are generated. However, the liquid in the water channel quickly stands still and solid matter (sediment Sludge) does not re-emerge or fly up. By the two swirling flows and the reversing flow, the solid matter having a large mass in the sewage is uniformly deposited on the tank bottom 10 ′ below the endless water channel 12, and is not deviated. In the case of the sewage treatment apparatus shown in FIGS. 1 and 2, as the supernatant treated water near the water surface inside the inner cylinder 11 overflows into the drain pipe 15 and is drawn out, the liquid outside the inner cylinder is filled with water. The SS, which enters the cylinder from below and is suspended in the liquid, sediments and deposits on the tank bottom 10 'below the inner cylinder in a sludge blanket shape.

In the case of the sewage treatment apparatus of the embodiment shown in FIGS. 3 and 4, a large number of carriers 18 to which microorganisms such as anaerobic bacteria and aerobic bacteria have adhered are densely supported inside the cylinder 11, It hangs down from the lower end of the inner cylinder to the tank bottom of the processing tank, or to an intermediate position between the tank bottom and the lower end of the inner cylinder. The carrier 18 may be a light-weight, flexible, nonwoven fabric having good cell-fixing properties, or a solid material made of plastic or the like and having good cell-fixing properties. A wire mesh support plate 19 is attached to the upper and lower ends of the densely packed carrier 18, the support plate to which the upper end is attached is fixed inside the inner cylinder 11, and the carrier is vertically pinned by the support plate attached to the lower end. It is preferable to prevent the carriers from individually moving in the water stream.

In this sewage treatment apparatus, as described above, two swirling flows and a reversing flow are generated in the water channel due to the intermittent water supplied to the endless water channel 12, but the liquid in the water channel is quickly settled. In addition, re-emerging and soaring of solid matter (sedimentary sludge) deposited on the tank bottom does not occur. Then, due to the two swirling flows and the reversing flow, the solid matter having a large mass in the sewage is converted into an endless waterway 1.
2 is uniformly deposited on the bottom 10 ′ of the tank, and does not deviate. Then, as the supernatant treated water near the water surface inside the inner cylinder 11 overflows into the drain pipe 15 and is drawn out, the liquid outside the inner cylinder is discharged from the dense carrier 18 descending from the lower end of the inner cylinder. It passes through the space and enters the inner cylinder from below and rises to the water surface, and its rising speed is reduced by the flow resistance of the carrier 18. The BOD component and the like in the liquid are biologically treated by contacting microorganisms attached to the carrier at that time, and the B of the treated water extracted through the drain pipe 15 is increased.
The OD concentration decreases.

In addition, since the sedimentation and separation of solids in the endless water channel 12 are efficiently performed, the overload of the solids with respect to the microorganisms attached to the carrier 18 is prevented, so that the biological treatment by the microorganisms is also efficient. Done in

Further, when the microorganisms attached to the carrier 18 proliferate, they are partly separated from the carrier and settle on the tank bottom 10 ', and biologically treat solid sludge deposited on the tank bottom.

A conventional settling tank (referred to as a conventional apparatus);
Figure 3 shows the results of a comparative experiment in which the combined wastewater (miscellaneous wastewater and flush toilet wastewater) of Family A was treated in the same period from March to August using the wastewater treatment device (referred to as an implementation device) shown in FIGS. 6
Shown in For the same tank volume, B
The OD concentration was reduced to almost half of the BOD concentration of the treated water of the conventional apparatus, demonstrating that the treatment apparatus had an extremely high treatment capacity. Further, the fluctuation width of the BOD concentration of the treated water is extremely small in the practical apparatus compared to the conventional apparatus. In FIG.
The SS concentration of the treated water is shown for the comparative example. S
As for the S concentration, similarly to the BOD concentration, the processing capacity of the working apparatus is much higher than that of the conventional apparatus.

FIG. 8 shows a conventional anaerobic filter bed tank (hereinafter referred to as a conventional apparatus) and a sewage treatment apparatus (executing apparatus) shown in FIGS. The result of the comparative experiment which treated the merged sewage of home is shown. The BOD of the treated water treated by the working apparatus is extremely stable as compared with the conventional apparatus. Also, the conventional apparatus has two anaerobic filter beds, whereas the apparatus used is a single tank, so that the capacity of the tank is small and no space is required for installation. FIG. 9 shows the SS concentration of the treated water in this comparative experiment. The SS concentration of the working device is
In addition to being lower than the conventional apparatus, the fluctuation range of the SS concentration is extremely small. In particular, after 100 days, the SS concentration of the conventional device is on the rise, and the first room is clogged because the second room is higher than the first room. On the contrary, SS in the implementation device
The concentration is very stable.

In the case where a large amount of bathtub drainage flows in at a time, the sewage treatment apparatus shown in FIGS.
Table 1 shows the BOD concentration and the SS concentration of the treated water from the conventional sedimentation apparatus and the conventional anaerobic filter bed tank. The value of the implementation device was much lower than the value of either of the two conventional devices, demonstrating that the throughput of the implementation device was high.

[Table 1]

[0022]

According to the sewage treatment apparatus of the present invention, sedimentation and separation of solids in sewage can be performed very efficiently. For this reason, this sewage treatment apparatus is used at the front stage of a relatively small, unsteady drainage of organic sewage purification facilities such as homes, offices, hotels, public halls, etc., so that the sewage treatment apparatus at the subsequent stage can be used. The load of solid matter and SS can be greatly reduced, which contributes to the improvement of the quality of the final treated water.

The wastewater treatment apparatus according to claim 2 enables efficient sedimentation and separation and biological treatment with microorganisms in a single treatment tank. Therefore, by using this sewage treatment apparatus at the front stage of a relatively small-scale, non-stationary drainage organic sewage purification facility such as homes, offices, hotels, public halls, etc. The load due to solids and SS can be greatly reduced, and the processing performance of denitrification, dephosphorization, etc., is improved, contributing significantly to the improvement of the quality of the final treated water.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of one embodiment of a sewage treatment apparatus according to claim 1;

FIG. 2 is a plan view of FIG.

FIG. 3 is a longitudinal sectional view of one embodiment of the sewage treatment apparatus according to claim 2;

FIG. 4 is a plan view of FIG. 3;

FIG. 5 is a schematic view showing a sedimentation / separation operation of the sewage treatment apparatus shown in FIGS. 1 and 3;

FIG. 6 is a comparison chart showing the BOD concentrations of treated water treated by a conventional sedimentation separation tank and the sewage treatment apparatus of the present invention.

FIG. 7 is a comparative chart showing SS concentrations of treated water treated by a conventional sedimentation separation tank and the sewage treatment apparatus of the present invention.

FIG. 8 is a comparative chart showing the BOD concentrations of treated water treated with a conventional two-bed anaerobic filter bed tank and the sewage treatment apparatus of the present invention.

FIG. 9 is a comparative chart showing SS concentrations of treated water treated by a conventional two-bed anaerobic filter bed tank and the sewage treatment apparatus of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Processing tank 10 'Tank bottom 11 Inner cylinder 12 Endless water channel 13 Water supply pipe 14a Branch jet port 14b Branch jet port 15 Drain pipe 16 Baffle plate 17 Support tool 18 Microorganism carrier 19 Support plate A Swirling flow B Swirling flow A' Inversion Flow B 'Reverse flow

Continuation of the front page (56) References JP-A-58-79510 (JP, A) JP-A-53-134277 (JP, A) JP-A-1-107405 (JP, U) JP-A-63-176503 (JP , U) Actually open 1979-57798 (JP, U) Actually open 1979-65104 (JP, U) Actually open 1979-26284 (JP, U) Actually open 1982 52-11278 (JP, U) Actually open 50-136858 (JP, U) Actually open Showa 50-122458 (JP, U) Actually open 50-113069 (JP, U) Actually open 50-50170 (JP, U) Actually open 48-58653 (JP, U U) Patent 111514 (JP, C2) Table 7-500279 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B01D 21/02 B01D 21/26 C02F 3/00 C02F 3 / 06 C02F 3/10

Claims (3)

(57) [Claims] 1. An inner cylinder having a lower end separated upward from the tank bottom and an upper end protruding above the water surface is vertically provided inside the processing tank, and an endless end is provided between the inner periphery of the processing tank and the outer periphery of the inner cylinder. A sewage treatment apparatus which forms a waterway, supplies raw water into the endless waterway by a water supply pipe, and draws out treated water from the inside of the inner cylinder to the outside of the treatment tank by a drainage pipe; At the tip of the water supply pipe, two branch jets are provided for supplying raw water to the endless water channel in the opposite direction and turning the same, and in the endless water channel, at a position directly opposite to the position where the water supply pipe is provided. A sewage treatment apparatus comprising a baffle plate crossing the endless waterway. 2. An inner cylinder having a lower end separated upward from the tank bottom and an upper end protruding above the water surface is vertically provided inside the processing tank, and an endless end is provided between the inner periphery of the processing tank and the outer periphery of the inner cylinder. A sewage treatment apparatus which forms a waterway, supplies raw water into the endless waterway by a water supply pipe, and draws out treated water from the inside of the inner cylinder to the outside of the treatment tank by a drainage pipe; At the tip of the water supply pipe, two branch jets are provided for supplying raw water to the endless water channel in the opposite direction and turning the same, and in the endless water channel, at a position directly opposite to a position where the water supply pipe is provided. A sewage treatment method comprising: providing a baffle plate that crosses an endless waterway; supporting a group of microorganisms adhering thereto in a dense manner inside an inner cylinder; and hanging the group of carriers from a lower end of the inner cylinder. apparatus. 3. The sewage treatment apparatus according to claim 1, wherein a baffle provided at a position directly opposite to a water supply pipe in the endless water passage connects the endless water passage. A sewage treatment apparatus characterized by being suspended so as to be able to swing across.