JPS62798Y2 - - Google Patents

Description

[Detailed explanation of the idea]

The present invention relates to a contact material for water treatment installed in an aeration tank. Recently, fixed bed catalytic oxidation methods using biofilms have been attracting attention among biological wastewater treatments such as activated sludge methods. This fixed-bed catalytic oxidation method involves filling an aeration tank with a contact material to which microorganisms can easily adhere, and bringing the wastewater into contact with air to oxidize the biofilm that grows epiphytically on the surface of the contact material, and then performs adsorption treatment. It is a system that Conventionally used contact materials in this case include synthetic resin nets, honeycomb modules with a three-dimensional network structure, and contact materials made of synthetic fiber strings arranged in a blind shape. Fixed beds using plastic mesh contact materials, such as the former, are easy to install in an aeration tank, but over time, the mesh becomes clogged due to the growth of attached biofilm, making it difficult for water to pass through. Therefore, in order to prevent this, the mesh spacing must be widened,
Therefore, there is a drawback that the contact area between water and the attached biofilm cannot be increased. Also the latter,
In other words, when the blind-shaped string described in JP-A-51-128835 is used as a contact material, the biofilm adhesion efficiency is high because the material is made of fine fibers, and the string is flexible. Because of this structure, it vibrates due to the circulating water flow in the aeration tank and does not cause blockages.
It was necessary to fix it by tying it together or gluing it, which required time-consuming and inefficient work. In view of the above points, the present invention has high biofilm adhesion efficiency, low water flow resistance, and high strength.
The purpose of this invention is to provide a contact material for water treatment that has many advantages such as being easy to transport and install. In other words, the present invention provides a contact material for water treatment consisting of a square ratchet mesh fabric in which a plurality of parallel chain stitch yarns are connected at predetermined intervals by insertion yarns to form rectangular through-holes. It is. Below, the configuration of the present invention will be explained in detail based on examples. FIG. 1 shows an example of the contact material for water treatment according to the present invention.
In this method, a plurality of chain knitting yarns 2 knitted to an appropriate thickness are arranged almost parallel to each other, and the chain knitting yarns 2 are connected at predetermined intervals by insertion yarns 3 to form rectangular through holes (mesh). ) section 4 is formed, and is composed of a so-called square ratchet mesh fabric. The materials for the contact material for water treatment of the present invention include organic fibers such as natural fibers and synthetic fibers, inorganic fibers such as glass fibers, mineral fibers, and metal fibers, or filament-like or spun-like fibers that are a mixture of these fibers. Select and use as appropriate. Each insertion yarn 3 in the square mesh ratcelle net fabric is selected from one or more monofilament yarns, multifilament yarns, or spun yarns as appropriate, and the width of the insertion portion is 1 to 1 from the viewpoint of biological attachment efficiency. 100mm is preferred. Furthermore, the distance between each chain knitting yarn 2, that is, the length of the inserted yarn 3, is 20 to 300 mm, the distance between each inserted yarn is 10 to 70 mm, and the area of each through hole 4 formed by these is 20 to 300 mm. is 2 to 200 cm ² in order to prevent blockage of the pores 4, and the ratio of the total area of the pores 4 to the net area (porosity) is 20 to 80%.
Preferably. Fig. 2 shows an example of the case where the water treatment contact material made of square mesh ratchet mesh according to the present invention is installed in an aeration tank.
Using the longitudinal direction as the transverse direction, for example, using the selvedge chain stitch yarn of the net fabric as the upper edge, attach the hanger 6 at an appropriate position depending on the size of the aeration tank 5, and meander into the aeration tank. Set up suspension. 7 is an air blowing pipe for aeration. Next, a specific example in which the contact material for water treatment according to the present invention is used will be described. A contact material with the following specifications was installed in the aeration tank as shown in Figure 2, and the underground water was treated.
The treatment status was investigated over a year. The results are shown in Table 1. Specifications for contact material for water treatment Material: Polyester multifilament Form: Square mesh rattle net (Figure 1) Porosity: 50% Perforation area: 6cm ² /piece Filling amount: 1m width x 20m length/m ² -Aeration tank

【table】

[Table] The treatment build-up was stable throughout the year, with satisfactory results of less than 20 mg of treated water BOD and less than 30 mg of SS.Also, as a result of observing the state of biofilm adhesion, it was found that biofilm was It was firmly attached to the knitted tissue in a screened state, and there was almost no clogging of the through holes. The contact material for water treatment according to the present invention is made of a square mesh mesh fabric, which can be set very easily in an aeration tank at regulated intervals, has a rectifying effect on water flow, and can pass through its perforations. Because a water flow that flows is obtained, there is little uneven flow, the adhesion of microorganisms is uniform, and no dead areas of flow occur. Furthermore, during treatment, the Latssel net fabric, which is the contact material for water treatment of the present invention, gently sways due to the aeration air and circulating water flow, just like a lace-like curtain swaying in a breeze, preventing contact between the attached biofilm and water. The sludge that has been raised and adhered to the sludge is constantly peeled off, and the biofilm does not thicken and a large amount of sludge does not suddenly fall off. It also has many advantages, such as being light, easy to handle, easy to transport, and requires little storage space.

[Brief explanation of the drawing]

FIG. 1 is a schematic plan view showing an example of the contact material for water treatment of the present invention, and FIG. 2 is a perspective view showing an embodiment of the contact material for water treatment of the present invention installed in an aeration tank. be. 1... Contact material for water treatment, 2... Chain knitting yarn, 3...
Insertion thread, 4...through-hole part.

Claims (1)

[Scope of utility model registration request] A contact material for water treatment consisting of a square ratchet mesh fabric in which a plurality of chain stitch yarns arranged in parallel are connected at predetermined intervals by insertion yarns to form rectangular through-holes.