JPH1028975A - Treatment of discharge water and device thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lower a contamination level (BOD, SS value, etc.), of discharge water exerting adverse effect to the environment. SOLUTION: This device is provided with a solid-liquid separator 24 having a netlike filter part, a storage tank 33 for temporarily storing the liquid component which has passed through the filter part of the solid-liquid separator 24, and a slurry pump 36 for conveying flock formed in the storage 1 to the solid- liquid separator 24 again, and the liquid component passed through the filter part of the solid-liquid separator 24 is temporarily stored in the storage tank 33 and then a flocculant is added to the liquid component in the storage tank 33 to generate the flock 34 and a supernatant liquid 35 in the storage tank 33 is discharge, and on the other hand, the flock 34 is again conveyed to the solid-liquid separator 24 by using the slurry pump 36 to perform solid-liquid separation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for treating garbage discharged from, for example, kitchens, garbage discharged from cafeterias, business establishments, and the like, and wastewater after solid-liquid separation and domestic wastewater. An apparatus for performing the method.

[0002]

2. Description of the Related Art Garbage from home kitchens, dining rooms, etc.
For example, the solid and liquid components are separated by a solid-liquid separator in which a coil-shaped screw (ribbon screw) is rotatably arranged in an annular space formed by concentrically combining inner and outer cylinders having a filtration unit (screen). Is discharged to the outside (river and sewage) as wastewater. Domestic wastewater such as domestic sewage is treated by a water treatment device such as a septic tank.
After the OD (biochemical oxygen demand) and SS (suspended matter) values are reduced to low levels, they are released outside (rivers and sewage).

[0003]

By the way, as described above, garbage is crushed and slurried with water and guided.
In a solid-liquid separator of a type that separates a solid content and a liquid content through a filtration unit, the size of the filtration hole of the filtration unit is about 1 to 2 mm. It flows out to the drainage pipe together with more liquid components and is released to the outside, adversely affecting the environment. Further, sludge accumulates in a water treatment device such as a septic tank, and the sludge needs to be periodically removed and cleaned, which is costly.

The present invention has been made in view of the above-mentioned conventional problems, and can reduce the pollution level (BOD, SS value, etc.) of wastewater which adversely affects the environment, and reduces the frequency of sludge extraction. It is an object of the present invention to provide a wastewater treatment method that can be used and an apparatus that performs the treatment method.

[0005]

In order to achieve the above-mentioned object, the present invention temporarily stores wastewater discharged to the outside, and adds a flocculant to the stored wastewater to generate flocs. Solid-liquid separation is to be performed. By adding a flocculant to the wastewater discharged to the outside to generate flocs, it is possible to significantly reduce fine solids contained in the wastewater and to reduce the frequency of sludge removal.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first wastewater treatment apparatus according to the present invention has a solid-liquid separator having a mesh-like filtration unit, and temporarily stores the liquid component passing through the filtration unit of the solid-liquid separator. The storage tank and a slurry pump for transferring the flocs generated in the storage tank to the solid-liquid separator again are provided.

A first method of treating wastewater according to the present invention is a method of treating wastewater after solid-liquid separation into a solid content and a liquid content through a mesh-like filtration unit. After temporarily storing the liquid component that has passed through the filtration unit of the solid-liquid separator constituting the first wastewater treatment device in a storage tank, a flocculant is generated by adding a flocculant to the liquid component in the storage tank. It is. And the supernatant liquid in the storage tank is drained,
The floc is transported again to the solid-liquid separator by using a slurry pump, and is subjected to solid-liquid separation.

[0008] A second wastewater treatment apparatus according to the present invention includes a water treatment apparatus for treating domestic wastewater, a storage tank for temporarily storing sludge deposited in the water treatment apparatus, and a storage tank for generating sludge in the storage tank. A solid-liquid separator for solid-liquid separating the flocs thus obtained, and a slurry pump for transferring the flocs in the storage tank to the solid-liquid separator are provided.

[0009] A second wastewater treatment method according to the present invention is a method for treating domestic wastewater, and is a water treatment for treating domestic wastewater constituting the second wastewater treatment apparatus according to the present invention. After the sludge accumulated in the apparatus is temporarily stored in a storage tank, floc is generated by adding a flocculant to the sludge in the storage tank. Then, the supernatant liquid in the storage tank is drained, while the floc is transferred to a solid-liquid separator by using a slurry pump to perform solid-liquid separation.

[0010] Further, a third wastewater treatment apparatus according to the present invention includes a water treatment apparatus for treating domestic wastewater, a solid-liquid separator having a mesh-like filtration unit, and a sludge deposited in the water treatment apparatus. A storage tank for temporarily storing the liquid component passing through the filtration unit of the solid-liquid separator, and a floc generated in the storage tank,
Again, a slurry pump for transferring to the solid-liquid separator is provided.

The third method of treating waste water according to the present invention is a method of treating waste water, and the third method of treating waste water according to the present invention described above.
After temporarily storing the sludge accumulated in the water treatment device that treats domestic wastewater and the liquid component that has passed through the mesh-like filtration unit of the solid-liquid separator, the sludge in this storage tank Then, a flocculant is added to the liquid component to generate floc. And the supernatant liquid in the storage tank is drained,
The floc is transferred to a solid-liquid separator using a slurry pump, and is subjected to solid-liquid separation.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A wastewater treatment apparatus according to the present invention will be described with reference to FIGS.
The present invention extends to the wastewater treatment method according to the present invention while being described based on the embodiment shown in FIG. FIG. 1 is a schematic configuration diagram of a first wastewater treatment device according to the present invention, FIG. 2 is a schematic configuration diagram of a second wastewater treatment device according to the present invention, and FIG. 3 is a third wastewater treatment device according to the present invention. FIG. 4 is a schematic vertical sectional view showing an example of a solid-liquid separator applied to the wastewater treatment apparatus according to the present invention.

In FIG. 1, reference numeral 31 denotes, for example, a kitchen sink. The garbage inserted from the sink 31 is crushed into small pieces by a cutter or crusher (hereinafter referred to as a "crusher") 32, and then water is added thereto. Along with the feed pipe 22 to the filtration unit 1 of the solid-liquid separator 24, where the solid-liquid separation is performed into a solid content and a liquid content.

The solid-liquid separator 24 has, for example, a structure as shown in FIG.
The structure of will be described. In FIG. 4, reference numeral 1 denotes a filtration unit that forms an annular space 1 c by concentrically arranging a filtration outer cylinder 1 b formed of a mesh-like member and a filtration outer cylinder 1 b formed of a mesh-like member, The lower end of the filtration inner cylinder 1a is connected to the drain pipe 2, and the lower end of the filtration outer cylinder 1b is fixed to the machine base 3.

Reference numeral 4 denotes a driving wheel rotatably supported by the machine base 3 via a bearing 5. A gear 6 is externally fitted and fixed to a lower outer periphery of the driving wheel, and a driving source is connected to a pinion 7 meshed with the gear 6. The rotation of a certain motor 8 is transmitted. The upper surface of the drive wheel 4 is provided with a coil-shaped ribbon screw 9 inserted into an annular space 1c formed by the filtration inner cylinder 1a and the filtration outer cylinder 1b.

On the inner and outer circumferences of the upper end of the ribbon screw 9, recesses are provided, respectively.
A key portion that fits into a concave portion provided on the outer peripheral portion of the ribbon screw 9 is provided on the inner peripheral portion of the rotational force transmitting plate 13 attached to the upper surface of the auxiliary plate 12 in which the cleaning plate 11 is installed in a hanging manner. The rotation of the ribbon screw 9 is transmitted to the cleaning plate 11. The cleaning plate 11 has a length capable of covering substantially the entire area in the height direction of the filtration outer cylinder 1b, and its side surface is arranged with a slight gap from the outer peripheral surface of the filtration outer cylinder 1b.

Reference numeral 14 denotes a rotary plate attached to the ribbon screw 9 similarly to the rotational force transmitting plate 13, and a key which fits into the outer peripheral portion of the rotary plate 14 and the concave portion provided in the inner peripheral portion of the ribbon screw 9. A portion is provided to transmit the rotation of the ribbon screw 9 to the shaft 15. And
A feed blade 16 is attached to an upper portion of the shaft 15, and a cleaning screw 17 inserted into the filtration inner cylinder 1a is attached to a lower portion of the shaft 15 so as to rotate. The cleaning screw 17 has an outer peripheral portion that is slightly spaced from the inner peripheral surface of the filtration inner cylinder 1a, and has a length that can cover substantially the entire area in the height direction of the filtration inner cylinder 1a. It has a coil shape in the reverse winding direction to the screw 9 (direction for transferring the deposits attached to the inner peripheral surface of the inner filtering tube 1a downward).

Reference numeral 18 denotes an electromagnetic gate valve interposed in the drain pipe 2.
For storing water in the filter unit 1 and discharging water from the filter unit 1. The sensor 21 is disposed above a drain pipe 20 provided in a casing 19 in which the filter unit 1 is installed.
Thus, the amount of water stored in the filtration unit 1 is detected. Reference numeral 23 denotes a discharge pipe installed above the casing 19.

In the solid-liquid separator 24 having the filtration unit 1 as described above, the size of the filtration holes of the inner filtration tube 1a and the outer filtration tube 1b is about 1 to 2 mm. Contains a fine solid content, and is discharged from the drain pipe 2 in a state containing the solid content.

Therefore, in the first wastewater treatment apparatus according to the present invention, the wastewater containing fine solids discharged from the wastewater pipe 2 is once introduced into the storage tank 33 as shown in FIG. And store it. Then, by adding a flocculant into the storage tank 33, the floc 34 is generated in a fine solid content and settled in the storage tank 33.

After the wastewater containing fine solids is stopped in the storage tank 33 for a certain period of time, the supernatant liquid 35 in the storage tank 33 is drained to the outside. On the other hand, the floc 34 that has settled in the storage tank 33 is again
And then solid-liquid separated. The solid separated from the solid is passed through the discharge pipe 23 and sent to the next step, for example, the biodegradation processing section 37.

As described above, in the first method for treating waste water according to the present invention, the liquid waste discharged from the kitchen and the like discharged from the kitchen or the like after solid-liquid separation in the filtration unit 1 is stored in the storage tank 33. Then, after a floc is formed by adding a flocculant into the storage tank 33, the floc is transferred to the solid-liquid separator 24 again for solid-liquid separation. Can be significantly reduced.

Next, a second wastewater treatment method according to the present invention will be described with reference to FIG. In FIG. 2, reference numeral 38 denotes a water treatment device such as a septic tank for treating domestic wastewater such as domestic wastewater. The domestic wastewater is discharged to the outside after the BOD and SS values are reduced to a low level by the water treatment device 38. Is done.

In the water treatment device 38, sludge 39 accumulates in the process of treating domestic wastewater.
In the wastewater treatment apparatus described above, a storage tank 33 is provided, and the deposited sludge 39 is transferred using, for example, a slurry pump 40 and temporarily stored. The floc 34 is generated by adding a flocculant to the sludge 39 in the storage tank 33, and the floc 34 is precipitated in the storage tank 33.

After the wastewater containing the floc 34 is stopped in the storage tank 33 for a certain period of time, the supernatant liquid 35 in the storage tank 33 is drained to the outside. On the other hand, the floc 34 settled in the storage tank 33 is transferred to the solid-liquid separator 24 using a slurry pump 36, where the solid-liquid separation is performed. The solid separated from the solid is passed through the discharge pipe 23 and sent to the next step, for example, the biodegradation processing section 37.

As described above, in the second method for treating wastewater according to the present invention, the sludge 39 generated in the process of treating domestic wastewater is stored in the storage tank 33, and the flocculant is stored in the storage tank 33. After the addition of the floc 34 to generate the floc 34, the floc 34 is transferred to the solid-liquid separator 24 by the slurry pump 36 for solid-liquid separation, so that the frequency of extracting the sludge 39 can be reduced.

Next, a third wastewater treatment method according to the present invention will be described with reference to FIG. The wastewater treatment apparatus shown in FIG. 3 is composed of domestic wastewater such as domestic wastewater and liquid waste of garbage which is inserted from a sink 31 and crushed into small pieces by a crusher 32 and then solid-liquid separated by a solid-liquid separator 24. The domestic wastewater among the above-mentioned wastewater is discharged to the outside after the BOD, SS value and the like are reduced to a low level by the water treatment device 38. On the other hand, the water treatment device 38
Sludge 39 accumulated in the process of treating domestic wastewater
Is temporarily stored by being guided to a storage tank 33 using a slurry pump 40, for example. Further, the liquid component discharged from the drain pipe 2 of the solid-liquid separator 24 is once guided to the storage tank 33 and stored together with the sludge 39 described above.

The floc 34 is generated by adding a flocculant to the sludge 39 and the liquid content in the storage tank 33, and the floc 34 is precipitated in the storage tank 33. After the wastewater containing the floc 34 is stopped in the storage tank 33 for a certain period of time, the supernatant liquid 35 in the storage tank 33 is drained to the outside. On the other hand, the floc 34 settled in the storage tank 33 is transferred to the solid-liquid separator 24 using a slurry pump 36, where the solid-liquid separation is performed. The solid separated from the solid is passed through the discharge pipe 23 and sent to the next step, for example, the biodegradation processing section 37.

As described above, in the third method for treating wastewater according to the present invention, sludge 39 generated in the process of treating domestic wastewater and garbage discharged from a kitchen or the like are solid-liquid separated by the filtration unit 1. After that, the liquid component to be released to the outside is stored in the storage tank 33,
After the floc 34 is generated by adding a flocculant into the storage tank 33, the floc 34 is transferred to the solid-liquid separator 24 by the slurry pump 36 to perform solid-liquid separation.
Can be reduced, and fine solids discharged to the outside can be significantly reduced.

The storage tank 33 that constitutes the wastewater treatment apparatus of the present invention is only required to be able to store the liquid component containing fine solids and the sludge 39. If it is arranged, operation management can be easily performed. In the second and third embodiments, the sludge 39 is transferred to the storage tank 33 by using the slurry pump 40. However, the slurry pump 40 is unnecessary if the sludge can be transferred by other means.

[0031]

As described above, according to the present invention,
By adding a flocculant to the wastewater discharged to the outside to generate flocs, the fine solid content contained in the wastewater can be significantly reduced, and the pollution level of the wastewater which has a bad influence on the environment can be reduced. In addition, the frequency of troublesome sludge extraction can be reduced,
Running costs are reduced. Further, one solid-liquid separator can simultaneously treat domestic wastewater and wastewater resulting from kitchen garbage discharged from a kitchen or the like.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a first wastewater treatment device of the present invention.

FIG. 2 is a schematic configuration diagram of a second wastewater treatment device of the present invention.

FIG. 3 is a schematic configuration diagram of a third wastewater treatment device of the present invention.

FIG. 4 is a schematic longitudinal sectional view showing an example of a solid-liquid separator applied to the wastewater treatment device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Filtration part 24 Solid-liquid separator 33 Storage tank 34 Flock 35 Supernatant liquid 36 Slurry pump 38 Water treatment device 39 Sludge

Claims (6)

[Claims] 1. A method for treating waste water after solid-liquid separation into a solid content and a liquid content through a mesh-like filtration unit, wherein the liquid content passing through the filtration unit is temporarily stored and then stored. A method for treating wastewater, comprising adding a flocculant to the separated liquid to generate flocs, draining the supernatant, and solidifying the flocs again. 2. An apparatus for carrying out the method for treating wastewater according to claim 1, wherein the solid-liquid separator having a mesh-like filtration unit and a liquid component passing through the filtration unit of the solid-liquid separator are temporarily separated. An apparatus for treating wastewater, comprising: a storage tank for storing, and a slurry pump for transferring the flocs generated in the storage tank to the solid-liquid separator again. 3. A method for treating domestic wastewater, comprising temporarily storing sludge generated by treating the domestic wastewater with water, and then adding a flocculant to the stored sludge to generate flocs; A method for treating wastewater, wherein the supernatant is drained, and the floc is separated into solid and liquid. 4. An apparatus for carrying out the method for treating wastewater according to claim 3, comprising: a water treatment apparatus for treating domestic wastewater; a storage tank for temporarily storing sludge accumulated in the water treatment apparatus;
An apparatus for treating wastewater, comprising: a solid-liquid separator for solid-liquid separating flocs generated in the storage tank; and a slurry pump for transferring the flocs in the storage tank to the solid-liquid separator. 5. A method for treating wastewater, comprising temporarily storing sludge generated by treating domestic wastewater and a liquid component having passed through a mesh-shaped filtration unit, and then storing the stored sludge and the liquid component. A flocculant by adding a flocculant to the mixture, draining the supernatant, and solid-liquid separating the floc. 6. An apparatus for performing the wastewater treatment method according to claim 5, wherein the water treatment apparatus treats domestic wastewater, a solid-liquid separator having a mesh-like filtration unit, and the water treatment apparatus. A storage tank for temporarily storing the deposited sludge and the liquid component that has passed through the filtration unit of the solid-liquid separator, and a slurry pump for transferring the floc generated in the storage tank to the solid-liquid separator again. A wastewater treatment device characterized by the following.