JP2665168B2 - Solid-liquid separator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid-liquid separation apparatus used for separating solid substances contained in sewage liquid flowing into a sewage treatment plant prior to purification treatment.

[0002]

2. Description of the Related Art In a conventional solid-liquid separator, a solid-liquid separator, such as a bar screen or a perforated plate, for filtering and separating solids is partially or constantly removed from a wastewater. It is provided in a state where it is exposed according to the water level of the drainage liquid. For this reason, the portion where the solid matter adheres may be exposed from the lower drainage liquid. I try to collect solids,
There is a problem that the solid matter exposed to the air dries and adheres to the solid-liquid separator, which makes the recovery troublesome.

[0003] In the solid-liquid separation device, solids adhered to the solid-liquid separator by filtration must be periodically collected. For that purpose, generally, a scraping means for scraping and collecting solids while moving along the surface of the solid-liquid separator is used, but it is driven by a driving means such as an electric motor, for example. I have.

[0004] To drive the scraping means,
As a matter of course, the greater the separation resistance of solids from the solid-liquid separator, the greater the driving energy, and therefore the higher the running cost of the solid-liquid separator, and the larger the drive system mechanism, the larger the solidification. The size of the entire liquid separation device also increases.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of such a conventional situation. In a solid-liquid separation device, the solid-liquid separator is used to separate the solid-liquid separator from the wastewater regardless of the flow rate. To reduce the running cost and downsizing of the solid-liquid separator by reducing the load on collecting solids from the solid-liquid separator by scraping means etc. It is an object.

[0006]

According to the present invention, for this purpose, a solid-liquid separator such as a bar screen or a perforated plate provided in a flow passage through which a wastewater containing solid matter flows down from the wastewater containing the solid matter is used. For the solid-liquid separation device that filters and separates matter, a step is provided in the flow path of the lower drainage liquid so that the downstream flow path bottom is lower than the upstream flow path bottom, and from this step to the downstream side. A solid-liquid separator is provided so as to face the downstream channel bottom while maintaining the height level of the upstream channel bottom, and a water level adjusting weir is provided downstream of the solid-liquid separator, and By adjusting the water level of the lower effluent liquid flowing through the solid-liquid separator by the regulating weir, the water level downstream of the solid-liquid separator is kept at least at the level of the bottom of the flow path upstream of the step. Like that.

[0007] This solid-liquid separator effectively utilizes the characteristics of the flow path of sewage liquid in a sewage treatment plant or the like. That is, in the case of a solid-liquid separation device used in a sewage treatment plant, a sand basin is provided in front of it, and a large solid is separated by the solid-liquid separation device, and then fine solids such as sand are settled in the sand basin. After being separated, the sewage liquid is led to a purification facility. In general, the water level of the lower drainage in the flow path leading to the solid-liquid separator is substantially equal to the water level of the lower drainage flowing out of the sand basin. For this reason, as in the present solid-liquid separation device, a step portion is provided in the flow path of the lower drainage liquid, and from this step portion, at a level of the height of the upstream flow path bottom and substantially horizontal to the downstream flow path bottom. By providing the solid-liquid separator in a state of being covered, the water level downstream of the solid-liquid separator can be maintained at substantially the same level as or higher than the height of the flow path bottom on the upstream side of the step portion. Thus, the solid-liquid separator can always be entirely immersed in the lower drainage liquid as long as the lower drainage liquid flows. Therefore, in the solid-liquid separation device according to the present invention, a sand basin or the like can be used as a water level adjusting weir.

As a result, it is possible to solve the problem that the solid-liquid separator is exposed from the lower drainage liquid and spreads a bad smell.

Further, in this solid-liquid separator, the solid-liquid separator is submerged in a substantially horizontal state, so that the buoyancy of the solid waste adhering to the solid-liquid separator is always applied to the solid-liquid separator by the drainage liquid. The solids separate from the solid-liquid separator and the resistance to separation of the solids can be reduced accordingly. Therefore, the load on the scraping means for collecting the solid can be reduced, and the running cost and the size of the solid-liquid separator can be reduced.

Further, since the solid-liquid separator is in a horizontal state, it is possible to use the downward force of the lower drainage liquid when scraping solids while moving the scraping means along the surface of the solid-liquid separator. The driving load of the scraping means can be reduced by that much, which also leads to a reduction in the running cost and size of the solid-liquid separation device. In order to take advantage of such advantages, in the present invention, the solid-liquid separation device as described above, while moving the scraping means for scraping solids from the surface of the solid-liquid separator from the upstream side to the downstream side, By scraping the object, the force of the drainage liquid flowing down through the solid-liquid separator is applied to the scraping means.

In the present invention, a movable weir is provided downstream of the solid-liquid separator as a water level adjusting weir so that the buoyancy of the lower drainage liquid as described above can be utilized more positively. The movable weir allows the level of the drainage liquid flowing through the solid-liquid separator to be positively adjusted. In other words, according to this structure, when the movable weir is also operated to raise the water level of the lower drainage liquid flow when the scraping means is driven, for example, once every 30 minutes or once an hour, the water level rises with this rise. The dynamic buoyancy force acts on the solid matter attached to the solid-liquid separator, and the resistance to scraping off the solid matter can be further reduced.

[0012]

Embodiments of the present invention will be described below. In the embodiment shown in FIGS. 1 and 2, a solid-liquid separator, specifically, a bar screen 4 is submerged in a flow path 3 through which a lower drainage liquid 2 containing a solid substance 1 flows. This is a solid-liquid separator having a structure provided in a substantially horizontal state. More specifically, the flow path 3 is provided with a step 3s in which the downstream flow path bottom is lower than the upstream flow path bottom, and the height of the upstream flow path bottom from this step 3s is set. The bar screen 4 is provided so as to cover the downstream flow path bottom in a substantially horizontal state. Although not shown at the end of the solid-liquid separation device,
There is a sand basin, and the sand basin serves as a weir so that the water level of the lower drainage liquid 2 in the flow path 3 is maintained at least at the level of the flow path bottom upstream of the step 3s.

Most of the drainage liquid 2 flowing down the flow passage 3 passes over the bar screen 4 so as to ride on the bar screen 4, and at that time, the solid matter 1 is separated. Solid 1
The liquid stream 5 having a small solid content and a large amount of water from which the water is separated flows through the flow path 6 to the next step. On the other hand, a part of the lower drainage liquid 2 does not pass through the bar screen 4 and flows to another path as a multi-solids / small water flow liquid 7 containing a large amount of the solids 1. Specifically, an opening 9 is provided at an end 8 of the bar screen 4, and an outlet 10 which is separated from the liquid flow 5 is provided with a gate 11 and is led to a removing channel 12 which is also used as a refuse reservoir. Thereafter, predetermined processing is performed by a processing device (not shown).

The flow path 6 of the liquid flow 5 is provided with a movable weir 13 whose water level is adjustable. The level of the liquid stream 5 can be adjusted by the movable weir 13. This level control has two functions. One of them is the scraper 1
The water level of the liquid flow 5 is rapidly raised when scraping solid matter adhered thereto from the bar screen 4 by the bar 4, and the solid matter adhered to the bar screen 4 is removed by utilizing the buoyancy generated by the sudden rise of the water level. It is easy to separate and reduce the scraping load.

Another one is to adjust the level of the liquid stream 5 so as to adjust the level of the liquid stream 7 to be balanced with that level. In other words, the water level of the liquid flow 7 guided to the removal flow path 12 which is also used as the refuse accumulation can be adjusted according to the amount of the solid matter 1. Further, when opening the gate 11 of the removal channel 12 which is also used as a garbage accumulation, and transferring the solid 1 to the next processing step, it is possible to raise the water level and to flush the solid 1. This is advantageous for the transfer of a large amount of solids with a small amount of water when the solids 1 are pulverized using, for example, a pulverizer in the next processing step.
In addition, the efficiency of the crushing process is improved because the solids 1 such as dust can be continuously poured into the crusher simply by raising the water level of the liquid flow 7. In addition, in the case where a device for further processing such as separation / removal, shredding, or crushing of solid matter 1 such as dust is additionally provided as the next processing step, the processing efficiency can be similarly improved. .

The bar screen 4 is combined with a scraping means R for scraping the solids 1 separated and removed from the lower drainage liquid 2 from the bar screen 4 and scraping the solids 1 in the direction of the removal channel 12 which is also used as a dust accumulation. ing. The scraping means R uses a scraping body 14 that bites along the eyes of the bar screen 4 but is not in contact with the bar screen 4 and a soft material such as rubber that is in close contact with the surface of the bar screen 4. The scraper 15 is formed of a scraper 15. The scraper 15 roughly scrapes the solid matter caught between the eyes of the bar screen 4, and the scraper 15 also removes the fine solid matter adhering to the surface of the bar screen 4. They are scraped off without being left behind (see FIG. 7).

The scraping means R is designed to scrape off solids while moving in the downward direction of the lower drainage liquid 2. Therefore, the lower drainage liquid 2 is moved during the scraping operation on the bar screen 4. Is pushed in the operation direction by the liquid flow. As a result, the driving force for driving the scraping means R can be reduced. Further, since the bar screen 4 is in a submerged state, the buoyancy of the lower drainage liquid 2 acts on the solid adhered to the bar screen 4 so that the solid is lifted off the bar screen 4, and as a result, the solid is scraped off. It is in a state where it can be easily taken, which also contributes to the reduction of the driving force for driving the scraping means R.

FIGS. 3 to 5 show a modification of the above embodiment. In FIG. 3, a bar screen 4 is provided with a slight downward gradient toward the downflow direction of the lower drainage liquid 2 so as to serve also as a garbage collection. The bottom 16 of the removal channel 12 is at the same level as the end 8 of the bar screen 4. The embodiment shown in FIG. 4 uses a curved bar screen 17 so that the scraping means R can be operated by a crank mechanism. In the embodiment shown in FIG. 5, the bar screen 4 is provided with a slight upward gradient toward the downflow direction of the lower drainage liquid 2.

The example shown in FIG. 6 is a reference example of the present invention.
An arc-shaped bar screen 18 is provided vertically submerged in a liquid flow. Scraping body 14 and scraper 15
Is rotated about the center of the arc-shaped bar screen 18 as an axis 19, and the solid 1 separated and removed from the lower drainage liquid 2 does not pass through the bar screen 18 and contains many solids 1 The water is swept in the direction of the liquid flow 20. The scraper 15 adheres to the wall 23 of the removal channel 22 which is also used as a dust accumulation and is separated from the small solid matter / multiple water quantity liquid stream 21 from which the solid matter 1 is separated and removed through the bar screen 18. A scraping rod 24 for scraping off the solid 1 is fixed.

[0020]

As described above, according to the solid-liquid separator of the present invention, it is possible to eliminate the problem that the solid-liquid separator is exposed from the sewage and diffuses a bad smell. The scraping load of the means can be greatly reduced, and the running cost and size of the solid-liquid separation device can be reduced.

[Brief description of the drawings]

FIG. 1 is a schematic plan view of a solid-liquid separation device according to the present invention, with a part omitted.

FIG. 2 is a schematic sectional view of the solid-liquid separation device of FIG.

FIG. 3 is a schematic sectional view of a solid-liquid separation device according to another embodiment of the present invention.

FIG. 4 is a schematic sectional view of a solid-liquid separation device according to another embodiment of the present invention.

FIG. 5 is a schematic sectional view of a solid-liquid separation device according to another embodiment of the present invention.

FIG. 6 is a plan view of a solid-liquid separation device that is a reference example of the present invention.

FIG. 7 is an essential part perspective view showing the relationship between the scraping means and the bar screen.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Solid matter 2 Lower drainage liquid 3 Flow path 3s Step part 4 Bar screen (solid-liquid separation body) 6 Flow path 13 Movable weir R

Claims (3)

(57) [Claims] 1. A solid-liquid separation device for filtering and separating a solid from a wastewater containing a solid by a solid-liquid separator such as a bar screen or a perforated plate provided in a flow path through which the wastewater flows down,
In the lower drainage flow path, a step is provided in which the downstream flow path bottom is lower than the upstream flow path bottom, and the height of the upstream flow path bottom is maintained from this step to the downstream side. The solid-liquid separator is provided so as to face the flow path bottom on the downstream side, and a water level adjusting weir is further provided downstream of the solid-liquid separator, and the water level adjusting weir lowers the solid-liquid separator. A solid-liquid separator characterized by maintaining the water level downstream of the solid-liquid separator at least at the height level of the flow path bottom upstream of the step by adjusting the water level of the drainage liquid flow . 2. A method for scraping solids by moving a scraping means for scraping solids from the surface of the solid-liquid separator from an upstream side to a downstream side. 2. The solid-liquid separation device according to claim 1, wherein a downward force of the sewage liquid flowing down through the solid-liquid separator is applied. 3. The solid-liquid separation device according to claim 1, wherein a movable weir is provided downstream of the solid-liquid separator as a water level adjusting weir.