JPH10328505A - Concentration type coagulating reactor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a concentration type coagulating reactor to continuously maintain stable concentration efficiency by incorporating a mechanism with a simple construction for completely preventing a slit used for solid-liquid separation of a coagulated material from being clogged by the coagulated material. SOLUTION: In a concentration type coagulating reactor capable of performing the coagulation and separation/concentration of a liquid to be treated by a single device and in which a concentrating screen 1 is arranged, the concentrating screen 1 is made into a corrugated cylinder type and the direction of the slit mesh of the screen 1 is made to the horizontal direction. The diameter of bristles of a brush 5 is made smaller than the aperture of the slit mesh, the end of bristles of the brush 5 is passed through the slit mesh and the length of the bristles of the brush 5 is made so as to be brought barely into contact with the support wire of the screen. The brush 5 is rotated relative to the screen 1 while it is brought into contact with the slit surface to remove the coagulated products.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an agglutination reaction apparatus used for concentrating and separating suspended substances and the like from sludge and wastewater, and more particularly to an apparatus for simultaneously performing agglutination reaction and concentration / separation of agglomerated products. It relates to a possible concentration type agglutination reaction device.

[0002]

2. Description of the Related Art In order to separate suspended substances and the like from sludge and wastewater, first of all, a suspended substance and the like are aggregated from wastewater by an aggregation method, and the aggregated pellets are separated by solid-liquid separation. If the solid-liquid separation device is installed separately from the coagulation device, the pellet may be broken while transferring the coagulated pellets from the coagulation device to the solid-liquid separation device. Good to do. Usually, the concentration-type agglutination reaction device is provided with a slit-type solid-liquid separation device for concentration separation. Conventionally, when the suspended solids and the like in sludge and wastewater are aggregated using a concentration-type agglutination reaction device, and when the agglomerated pellets are concentrated and separated, the agglomerated pellets agglomerated in the reaction tank of the device have a particle size of 2 It grows to about 10 mm. The liquid to be treated including such agglomerated pellets is passed through a concentration / separation slit in the reaction tank, whereby a part of the separated water is discharged out of the system, and the suspension containing the agglomerated pellets ( The liquid to be treated) is concentrated.

FIG. 8 is a longitudinal sectional view conceptually showing a typical concentration type agglutination reaction apparatus. The treatment of the liquid to be treated by the concentration-type agglutination reaction device will be described below with reference to FIG. In FIG. 8, the shape of the concentration-type agglutination reaction device 7 is a vertical cylindrical shape,
A sludge supply pipe 8 and a polymer supply pipe 9 are connected to a lower side surface of the reactor 7, a concentrated sludge outflow pipe 10 is connected to an upper side surface, and a separated water outflow pipe 11 is connected to a middle side surface. A driving device 13 is provided above the reaction device 7, and the driving device 13 rotates a stirring blade 14 attached to a shaft 16 for stirring the inside of the tank 12 of the reaction device 7 and a scraper 18. As shown in FIG. 4, the screen 19 for separating the separated water has a structure in which the ring-shaped wedge wires 2 are horizontally arranged, and they are vertically stacked at intervals of, for example, 1 mm, and are fixed by the support bar 4 which extends vertically. belongs to. This structure will be described later in detail. A draft tube 17 for increasing the upward flow velocity on the surface of the screen 19 is provided at the center of the tank 12. The sludge which is the liquid to be treated is stirred by the stirring blades 14, and while being lifted to the screen 19 position by the draft tube 17, suspended substances and the like in the liquid are aggregated, and the aggregated pellets are solid-liquid separated by the screen 19. Since the separated water passing through the screen 19 goes out, the concentration of the suspended matter in the tank 12 rises, and the concentrated sludge (including coagulated pellets) is discharged out of the system from the concentrated sludge outlet pipe 10 and the separation is performed. Water is discharged out of the system from the separated water outflow pipe 11. The separated water flows naturally, and its flow rate is controlled by a telescope valve 15.

As described above, an aggregated product containing aggregated pellets (hereinafter referred to as “aggregated pellets”) usually stays in a tank for several minutes while being stirred by a water flow by a stirrer or the like disposed in the apparatus. Then, as in the above-described concentrated sludge, the concentrated sludge is transferred to the next step. However, when the agglomerated pellets in the agglutination reaction tank adhere to and accumulate on the separation slit of the screen while staying in the reaction tank, and the outflow of the separated liquid is prevented, the effective separation area of the slit decreases, The concentration efficiency decreases. Therefore, usually, the cross-flow velocity on the slit surface is increased, or a scraper or a brush is used near the slit surface to prevent adhesion and accumulation of aggregated pellets. Since it is desirable that these slit clogging prevention mechanisms have an effect without providing a new driving device for simplification of the device structure, they are often simple structures using the driving force of a stirrer in a tank. .

[0005] However, the effects of these simple clogging prevention mechanisms differ greatly depending on the properties of the aggregated products. Specifically, if the viscosity of the aggregated pellet and the separated water, the particle size of the aggregated pellet, and the shear strength are different, the degree of adhesion of the aggregated product to the slit surface and the degree of clogging of the slit are different. Sometimes it works and sometimes it doesn't. For example, when the particle size and shearing force of agglomerated pellets are both relatively large, such as sludge generated in a sewage treatment plant or activated sludge treatment facility, the conventional slit clogging prevention mechanism can sufficiently cope with such a problem. Waste fluids from factories handling wastewater and the like have a very small particle size, the shearing force of the aggregated pellets may be extremely small, and a part of the aggregated pellets may be broken to clog the slits. Therefore, the effect of the clogging prevention mechanism using the cross-flow water flow or the scraper may be insufficient. The mechanism for preventing clogging by a brush is often more effective than the above two methods because the brush surface can be brought into contact with the slit surface.

FIG. 4 shows an example of a screen of a screen-type solid-liquid separation device used in a coagulation reaction tank of a conventional concentration type coagulation reaction device. The screen 19 shown in FIG.
The ring-shaped wedge wires 2 are horizontally arranged, for example, stacked one by one at an interval of 1 mm in the vertical direction, and fixed by a support bar 4 extending in the vertical direction.
During the solid-liquid separation of the aggregated product including the aggregated pellets on such a screen 19, the aggregated pellets adhere and deposit on the separation slits of the screen 19, thereby preventing the outflow of the separated liquid. In order to easily and effectively prevent such clogging of the screen 19 by using the driving force of the stirrer of the agglutination reaction device, the brush 5 disposed inside the screen 19 is driven via the brush handle 20. It is preferable to connect and install the apparatus 13. Details of the arrangement of the brush 5 are as shown in FIG. 5 or FIG.

5 and 6, the brush 5 having the bristle 6 planted thereon is agitated in the tank 12 of the agglutination reactor instead of the scraper 18 in the illustration of the concentration type agglutination reactor 7 in FIG. Shaft 1 of the driving device 13
6 and is rotated together with the stirring blade 14 by the driving device 13. Further, depending on the properties of the sludge charged into the coagulation reaction tank 12, the rotation speed of the scraper 18 may be too high to cause the sludge to be scattered. In this case, the rotation speed of the scraper 18 is set higher than the rotation speed of the stirring blade 14. Since it is necessary to reduce the size, the speed reducer 21 may be inserted into the connection portion between the shaft 16 and the handle 20 of the brush. As shown in FIG. 5, a gap (clearance) is formed between the tip of the brush bristles 6 and the support bar 4 of the screen 19.
When a few millimeters are provided, clogging cannot often be completely prevented. However, when the point of the bristle 6 of the brush penetrates the slit as in the case shown in FIG. 6, the brush comes into contact with the support bar 4 supporting the slit while the brush rotates. However, the brush bristles 6 may not return as they are bent as shown in FIG. 7 due to a long operation, or may be worn, or the brush bristles may come off. In this case, the agglomerated product clogged in the thickness portion of the wedge wire 2 constituting the slit 19 is removed from the brush bristles 6.
Can not be scraped out. Therefore, it can be said that there are very few concentration-type agglutination reactors having a simple structure that completely prevent clogging of the separation slit depending on the properties of the agglutination product.

[0008]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the prior art and completely eliminates the clogging of the separation slit with a simple structure without using a driving device other than a stirrer for agglutination reaction. It is an object of the present invention to provide a concentration-type agglutination reaction device that incorporates a mechanism for preventing the concentration and enables continuous and stable concentration efficiency to be maintained.

[0009]

The present invention has solved the above-mentioned problems by the following means. (1) In a concentration-type agglutination reactor in which a concentration screen is arranged, which enables aggregation and separation / concentration of a liquid to be treated in a single device, the concentration screen has a wavy cylindrical shape, The direction of the slits of the concentrating screen is horizontal, and the diameter of the bristles of the brush is smaller than the size of the openings of the slits. A brush using a brush having a length contacting with the slit is rotated relative to the concentrating screen while contacting the slit surface, thereby removing a coagulated product. Reactor. (2) The shape of the wedge wire in the screen having the wavy cylindrical shape is wavy, and a support wire is provided at a valley portion of the wedge wire having the wavy shape, the valley portion being farther from the brush. Is connected, wherein the concentration-type agglutination reaction device according to the above (1) is connected.

More specifically, to explain more specifically, in order to solve the above-mentioned problems, in the present invention, in a concentration type agglutination reaction device, a wedge wire formed in a wavy ring shape and stacked at several millimeter intervals is used for concentration separation. Used as a screen slit, as a slit clogging prevention mechanism, adopts a method using a rotating brush that rotates in connection with the agitator in the tank and moves while contacting the slit on the slit surface,
Use a rotating brush whose brush bristle diameter is smaller than the slit eye width (the distance between wedge wires), and whose brush bristle has a length that penetrates the slit eye and makes slight contact with the support bar. The present invention employs a concentration-type agglutination reaction device. The position of the brush can correspond to either the primary side (concentrated sludge side) or the secondary side (separated water side) of the slit surface. (See Fig. 3)

One example of a slit used in the present invention, which is formed by forming a wedge wire into a wavy ring shape and overlapping at several millimeter intervals and having a rotary brush installed on the primary side (concentrated sludge side) of the slit surface. As shown in FIG. In FIG.
Reference numeral 1 denotes a screen having a structure in which wedge wires 3 in a wavy ring shape are horizontally arranged, and are stacked vertically at several millimeter intervals, and fixed by a support bar 4 which extends vertically. FIG. 2 illustrates a rotary brush installed on the primary side (concentrated sludge side) of the slit surface, and FIG. 3 illustrates a rotary brush installed on the secondary side (separated water side) of the slit surface. In the slit clogging prevention mechanism illustrated in FIGS. 2 and 3, since the bristle tips of the brush penetrate the slits, it is possible to almost completely remove the coagulated products attached to both surfaces of the slits. Since it does not collide with the wedge wire or the support bar structurally, the abrasion and bending of the hair tips are greatly improved. By connecting the support bar to the valley of the wavy wire at the valley far from the brush, the tip of the brush can be moved so as to pass through the slit but not contact the support bar.

In the concentration type agglutination reaction apparatus described above with reference to FIG. 8, the wedge wire of the present invention is replaced with a wavy ring shape instead of the conventional ring type screen 19,
A wavy ring-shaped screen 1 consisting of slits manufactured by being stacked at intervals of several millimeters is used, and the slit of the present invention and the rotating brush of the present invention (either attached to the primary or secondary side of the slit surface) )), The coagulation products are continuously removed from the slit surface and the increase in filtration resistance before and after the slit can be suppressed, so that the operation of the concentration type coagulation reaction device is continuous. And can be performed stably.

[0013]

EXAMPLES Specific examples will be shown below for better understanding of the present invention, but it is needless to say that the present invention is not limited by the following specific examples. Example 1 A test was carried out using a concentrating agglutination reaction apparatus of the present invention constituted by applying the screen of the present invention to the type shown in FIG. In this apparatus, a screen for separating the separated water has a wavy ring-shaped wedge wire made horizontal and superposed vertically at 1 mm intervals. Each wedge wire is fixed by a vertical support bar.
The brush bristles are made of a special neo-nylon material having strong abrasion resistance and shape memory and having a diameter of 0.4 mm. The tip of the brush is cut to a length that makes slight contact with the support bar. A draft tube 17 for increasing the upward flow velocity of the screen surface is provided at the center of the tank.
Separated water flows naturally, and its flow rate is controlled by telescope valve 1.
5 is performed.

The capacity of the device is 300 liters. The target sludge is a special wastewater SS concentration at the P chemical factory;
4.0 to 11.0 g / liter was used. The sludge was aggregated with an inorganic flocculant and a high molecular weight flocculating polymer in a flocculation reaction tank to form flocculated pellets. This P
The wastewater from a chemical factory had very fine particles of agglomerated pellets as compared with activated sludge and the like generated from a normal wastewater treatment plant, and the particle size was about 2 to 3 mm. The rate of addition of polymer per sludge to TS was 1.2% (wt). The inflow sludge amount is 8 m ³ / hour, and the separated water is 4 m ³
/ Hour. Under the above conditions, continuous operation for 24 hours
Went for months. Table 1 shows the processing results.

[0015]

[Table 1]

The average value of the processing results in the embodiment is the processing speed;
At 8.0 m ³ / hour, SS concentration of separated water: 87 mg / liter, and concentrated sludge concentration: 24.9 g / liter, continuous operation for 60 days or more was possible. Since the average value of the SS concentration of the treated water is 100 mg / liter or less, it can be said that the concentration and separation are performed very well.

[0017]

According to the concentration type agglutination reaction apparatus of the present invention, the screen for concentration / separation has a simple structure.
Agglomerated pellets are less likely to be clogged, the concentration and separation efficiency is good, and the brush has little damage and can be used for a long time.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating one embodiment of a screen of the present invention.

FIG. 2 shows a screen 1 according to the invention with an internal brush.
It is a partial explanatory view of an aspect.

FIG. 3 shows a screen 1 of the present invention having an external brush.
It is a partial explanatory view of an aspect.

FIG. 4 is a schematic view of a conventional typical screen.

FIG. 5 is an explanatory diagram showing a contact state when a brush is far from a screen in a conventional screen having an internal scraping brush.

FIG. 6 is an explanatory diagram showing a contact state when a bristle tip of a brush enters a slit in a conventional screen having an internal scraping brush.

FIG. 7 is an explanatory diagram showing a state of deformation of a brush tip in the case of FIG. 6;

FIG. 8 is a conceptual diagram of a concentration type agglutination reaction device.

[Explanation of symbols]

 Reference Signs List 1 screen 2 wedge wire 3 wavy wedge wire 4 support bar 5 brush 6 brush bristles 7 concentration type coagulation reaction device 8 sludge supply tube 9 polymer supply tube 10 concentrated sludge outflow tube 11 separation water outflow tube 12 coagulation reaction tank 13 drive device 14 Stirring blade 15 Telescope valve 16 Shaft 17 Draft tube 18 Scraper 19 Screen 20 Brush handle 21 Reduction gear

──────────────────────────────────────────────────続 き Continued on front page (51) Int.Cl. ⁶ Identification code FI B01D 29/37 35/22

Claims (2)

[Claims] 1. A condensing type coagulation reaction apparatus having a concentrating screen, wherein a condensing screen is arranged in a single apparatus for coagulating, separating and concentrating a liquid to be treated. The direction of the slits of the concentrating screen is horizontal, the diameter of the bristles of the brush is smaller than the opening of the slits, the bristle tip penetrates the slits, and the support wire of the screen A brush using a brush having a length slightly contacting with the slit and rotating the brush relatively to the screen for concentrating while removing the condensed product while contacting the slit surface. Type agglutination reaction device. 2. The shape of the wedge wire in the screen having the wavy cylindrical shape is wavy, and the valley portion of the wedge wire having the wavy shape is located at a valley portion farther from the brush. The concentration-type agglutination reaction device according to claim 1, wherein a support wire is connected.