JP3004964U - Contact filter medium - Google Patents

Abstract

(57) [Summary] [Purpose] The retention rate of the adhered organisms per unit volume of the contact filter medium is high, the volume efficiency is excellent, and the adhered organisms retaining capacity is excellent, and it is possible to always secure a stable treated water quality. In addition, the contact filter medium is easy to handle and transport and economical in transportation cost. [Constitution] Synthetic cotton and other chemical fibers are bound together.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a contact filter medium to be filled in an aeration tank when treating wastewater by the contact aeration method.

[0002]

[Prior art]

 As the conventional contact filter medium, natural products such as crushed stone may be used, but in general, it is generally made of a material such as plastic and has a cylindrical shape, honeycomb shape, corrugated plate shape, hollow spherical shape, skeleton shape, etc. Was used.

[0003]

[Problems to be solved by the device]

 Since the contact area of the contact filter media that uses crushed stones with the waste water per unit volume is small, the amount of biofilms composed of microorganisms that are effective in purifying the waste water is small in proportion to the contact area of the filter media. Moreover, since the weight per unit volume is large, there is a drawback that an excessive load is applied to the wastewater treatment facility.

The conventional contact filter formed of a material such as plastic is inferior in the sticking property and the retaining ability of the biofilm because the biofilm forming surface is smooth. Therefore, when the aeration strength in the aeration tank is increased, the biofilm is abnormally peeled or dropped, which causes the quality of treated water to deteriorate. Further, since the microorganisms generated in the conventional contact filter medium are limited to the surface of the filter medium in contact with the waste water, the amount of microorganisms retained per unit volume of the contact filter medium filled in the aeration tank was small and the volume efficiency was poor. Further, these contact filter media have a drawback in that they are inconvenient to transport due to the large volume per unit weight, which is uneconomical in terms of transportation cost.

The problem to be solved by the present invention is that the retention rate of the amount of microorganisms per unit volume of the contact filter medium to be filled is high, the volume efficiency is excellent, the ability to retain attached organisms is excellent, and the load amount of drainage and Sudden fluctuations in aeration strength do not lead to deterioration of the quality of treated water due to abnormal detachment or dropping of biofilm, and it is possible to secure stable treated water at all times, and the volume per unit weight is small, making it easier to transport. The purpose is to provide a contact filter medium that is convenient and inexpensive to transport.

[0006]

[Means for Solving Problems]

 The contact filter material according to the present invention is formed by binding synthetic cotton and other chemical fibers into a block body. The purpose of bundling the fibers is to prevent the fiber bundles from being dispersed by the water flow generated by the stirring in the aeration tank. As a method for binding the fibers, there are a method of directly binding the chemical fibers and a method of indirectly binding the fibers by enclosing the fibers in a net-like container such as a net bag. The former binding method includes a method in which one or a plurality of wound fiber bundles are bound with a corrosion-resistant string, adhered with an adhesive, or heat-sealed with high heat. In the latter binding method, a mesh bag made of synthetic fiber such as nylon and having any mesh size can be used. The shape of the contact filter medium formed in this manner can be any shape such as a bale shape, a spherical shape, a purse shape, and a beaded shape. Further, the contact filter medium of the present invention does not cause any damage due to corrosion under the condition of drainage water quality to which a normal biological treatment method is applied.

The contact filter according to the present invention is composed of an aggregate of chemical fibers such as synthetic cotton and has a rough surface for forming a biofilm, so that unlike a conventional contact filter, it is easy to adhere and generate a biofilm. Yes, it also has excellent retention capacity. Therefore, it is easy to adapt to rapid changes in the load of wastewater and aeration strength, and it is unlikely that the quality of the treated water will deteriorate due to abnormal detachment or falling of the biofilm.

The contact filter medium of the present invention is different from the conventional one, because when a biofilm is formed on the surface of the filter medium, microorganisms are also retained in the gaps between the fibers inside the filter medium. The retention rate of the amount of microorganisms per unit volume is high.

Since the material of the contact filter medium according to the present invention is an ultrafine chemical fiber such as synthetic cotton, in normal air, the gap between the fibers of the contact filter medium is filled with air and swells. The volume of the contact filter medium will be significantly reduced if it is stored in a closed container such as a container and the air in the container is extracted. When the volume of the contact filter medium that has been reduced in volume is returned to the atmosphere, it absorbs air and restores its original volume. As described above, the contact filter medium of the present invention is more convenient to handle and transport than conventional ones, and is economical in terms of transportation cost.

[0010]

[Action]

 Since the contact filter medium according to the present invention is a block body made of ultrafine chemical fibers such as synthetic cotton, microorganisms are generated and retained in the surface of the filter medium and in the fiber gaps inside the filter medium. Dissolved oxygen in the aeration tank is supplied aerobically to the surface of the filter medium that is in contact with the drainage of the biofilm, and is maintained anaerobically inside the filter medium. It is the aerobic part that is directly effective in treating wastewater, but the presence of the anaerobic part directly or indirectly treats the wastewater because it contributes to the water quality by reducing sludge generation and denitrification. It contributes to the improvement of the effect. Further, since this filter medium has the above-mentioned structure, it exhibits an excellent trapping action and filtering action of suspended matter.

[0011]

【Example】

 Example 1 FIG. 1 is a perspective view showing Example 1. In the first embodiment, the two binding portions 2 of the fiber bundle 1 of synthetic cotton are bound by high heat fusion to form a block body. In the case of Example 1, when the synthetic cotton is wound to an arbitrary thickness and fused to an arbitrary size by high heat such as an energized nichrome wire, the fiber bundle 1 can be bound and cut at the same time, and the arbitrary size can be obtained. The contact filter medium of is obtained. The contact filter medium of Example 1 can be directly filled in the aeration tank, but when it is filled in an aeration tank having an excessive aeration strength, the fiber bundle 1 is dispersed and collapsed by the stirring water flow in the tank. In order to prevent this, it is possible to store and fill in a mesh container such as a mesh bag having a mesh smaller than the size of the contact filter medium.

Second Embodiment FIG. 2 is a perspective view showing a second embodiment. In the second embodiment, the fiber bundle 1 of synthetic cotton is inserted into the mesh bag 3 made of synthetic fiber, enclosed and molded into a block body. The mouth sealing portion 4 for inserting the fiber bundle 1 into the mesh bag 3 may be repaired by any method, such as tying with a string or the like, bonding with an adhesive, heat fusion with high heat, or the like. In this case, the heat-melting is performed by using a net bag 3 made of a heat-soluble synthetic fiber.

[0013]

[Effect of device]

 Unlike the conventional contact filter media according to the present invention, aerobic micro-organisms easily inhabit the filter media surface and anaerobic microorganisms inside the filter media, which makes the aerobic treatment action more efficient than the conventional filter media. Also, since the anaerobic treatment process proceeds in parallel, it has an advantageous effect on denitrification and mineralization of sludge as well as removal of organic pollutants in wastewater. In particular, the effect of the denitrification action of the contact filter medium of the present invention is extremely effective for water purification of urban rivers, where pollution by domestic wastewater has become apparent in recent years. In addition, since this contact filter medium is easy to handle and transport, it is economical in terms of transportation cost.

[Brief description of drawings]

FIG. 1 is a perspective view showing a first embodiment.

FIG. 2 is a perspective view showing a second embodiment.

[Explanation of symbols]

 1 Fiber Bundle 2 Bundling Part 3 Net Bag 4 Blocking Part

Claims (2)

[Scope of utility model registration request] 1. A contact filter medium formed by binding chemical fibers into a block body. 2. The contact filter medium according to claim 1, wherein the chemical fiber is enclosed and contained in a net-like container.