JPS632084Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a rectifying net for a settling tank that is stretched within the settling tank.

There are several methods for separating particles and liquid in suspension, such as sedimentation, flotation, filtration, and centrifugation. Among these, sedimentation separation is used in fields such as the chemical industry, water supply, and sewage/wastewater treatment. This is a widely used solid-liquid separation method. In recent years, inclined plate settling tanks in which inclined plates are inserted into the settling tank have been frequently used to improve the separation effect. Slanted plate sedimentation tanks have a larger separation area compared to conventional settling tanks without inclined plates, so they can increase the liquid volume load, and also have a rectifying effect, which reduces fluctuations in the suspension liquid volume. However, on the other hand, it is extremely difficult to clean the particles deposited on the inclined plate surface, and it is difficult to discharge the sludge accumulated under the inclined plate. Moreover, since the sludge removal equipment was installed under the inclined plate, there were also disadvantages such as difficulty in maintaining the sludge collector and other equipment.
Furthermore, when installing the inclined plates, it took a great deal of time and effort to assemble and arrange them in the tank, and there were also problems in terms of construction and repair.

In view of the above points, it is an object of the present invention to provide a flow straightening net for a settling tank that has a large flow straightening effect, has low water flow resistance, is lightweight, and is easy to construct and transport.

That is, the present invention is a square ratchet net fabric in which a plurality of parallel chain knitting yarns are connected at predetermined intervals by inserting yarns made of a plurality of multifilament yarns to form rectangular through-holes. This invention relates to a rectifier net for a settling tank consisting of:

Below, the configuration of the present invention will be explained in detail based on examples. FIG. 1 shows an example of the rectifying net according to the present invention, in which a plurality of chain knitting yarns 2 knitted to an appropriate thickness are arranged approximately in parallel, and It is constructed of a so-called square mesh ratchet fabric in which the threads 2 are connected at predetermined intervals by insertion threads 3 made of a plurality of multifilament threads to form rectangular through holes (mesh) portions 4.

The materials for the rectifier net for the sedimentation tank of this invention include:
For example, organic fibers such as natural fibers and synthetic fibers, inorganic fibers such as glass fibers, mineral fibers, and metal fibers, or multifilament yarns that are a mixture thereof are used. Each inserted thread 3 in the square lattice mesh fabric
is composed of multiple multifilament threads, and the width of the inserted part is 1 to 50 mm from the viewpoint of rectification effect.
mm is preferred. Further, the distance between each chain knitting yarn 2, that is, the length of the inserted yarn 3, is 10 to 300 mm, and the distance between each inserted yarn is 10 to 70 mm, and the individual through holes 4 formed by these are 10 to 300 mm. It is preferable that the area is 3 to 200 cm ² in order to prevent blockage of the perforations 4, and the ratio of the total area of the perforations 4 to the net area (porosity)
is preferably 20 to 80%. Further, the net is bound and fixed by a band 6 to a support rod 5 passing through the through holes 4 at the upper and lower edges thereof.

Fig. 2 shows an example of a rectifying net made of square ratchet mesh according to the present invention installed in a horizontal flow type rectangular sedimentation tank. are suspended at appropriate intervals so that they are perpendicular to the flow direction. Also,
Fig. 3 shows an example of a rectifier net according to the present invention installed in a vertical flow type circular sedimentation tank, in which the rectifier net 1 is stretched around a support rod 5 formed in a concentric circle. . Next, a specific example in which the rectifier net according to the present invention is used will be described.

Rectifying net specifications Material: Polyester multifilament thread (10
Book) Format: Square rattle net (Fig. 1) 3m wide x
6m long net Porosity: 50% Perforation area: 6cm ² /pcs Rectifier net with the above specifications is 6m wide x 25cm long
4 m x 4 m deep horizontal flow type rectangular sedimentation tank, four sheets were suspended at 5 m intervals, and the sedimentation and flow conditions of particles in the sedimentation tank were investigated over a period of about one year.
The raw water that flows into the sedimentation tank is rectified by a rectifier net, and flows while spreading over the entire surface of the sedimentation tank, which alleviates disturbances and short-circuit flows inside the tank that occur when raw water flows in, as well as turbulence on the water surface caused by external temperatures and wind in winter. The system was able to adapt to sudden changes in water volume and turbidity, and no particle overflow occurred.

Furthermore, as shown in Figure 3, even when the above rectifier nets are stretched concentrically at 1 m intervals in a vertical flow type circular sedimentation tank (diameter 5 m, effective depth 4 m), raw water flowing into the tank is Without mixing the clarified layer, short-circuit flow and density flow phenomena that occur within the layer toward the overflow trough on the peripheral wall of the layer were suppressed, and the sedimentation efficiency of particles was increased.

It is not clear why the rectifying net of the present invention achieves a large rectifying effect, but the reason is that the chain knitting yarns are connected by insert yarns made of multiple multifilament yarns to form rectangular through-holes. When the water flow passes through the perforations in the settling tank, the water flow is rectified by the perforations formed by each inserted thread, and the individual multifilaments constituting each inserted thread are This is thought to be because the gap between the threads expanded by the water flow also receives a rectifying effect.

Since the rectifier net of the present invention has the above-mentioned configuration, it can be extremely easily set in the sedimentation tank, and has a great rectification effect on water flow, preventing disturbances and short circuits in the sedimentation tank. It has many advantages such as being able to reduce the flow and being lightweight, making it easy to handle and transport.

[Brief explanation of the drawing]

Fig. 1 is a schematic plan view showing an example of the rectifying net according to the present invention, and Fig. 2 is a perspective view showing an embodiment of the rectifying net according to the present invention installed in a horizontal flow type rectangular sedimentation tank. FIG. 3a is a schematic plan view showing an embodiment of the rectifying net according to the present invention installed in a vertical flow type circular sedimentation tank, and FIG. 3b is a schematic cross-sectional view thereof. DESCRIPTION OF SYMBOLS 1... Rectifier net, 2... Chain knitting yarn, 3... Insert thread, 4... Through-hole part, 5... Support rod, 6... Band.

Claims (1)

[Scope of utility model registration request] A sedimentation tank made of a square ratchet mesh fabric in which a plurality of parallel chain knitting yarns are connected at predetermined intervals by inserting yarns made of a plurality of multifilament yarns to form rectangular through-holes. Rectifier net for use.