Double-effect biological rotating disc device and process for treating sewage

Abstract

The application discloses a double-effect biological rotating disc device, which comprises a rotating shaft, inner disc plates fixed to the outer periphery of the middle part of the rotating shaft, outer disc plates fixed to the outer periphery of the two ends of the rotating shaft, a plurality of biological membrane plates between the inner disc plates and the outer disc plates, a rotating cage in the shape of a cylinder formed by surrounding the adjacent two inner disc plates with a grid, and biological membrane fillers placed in the rotating cage.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of environmental protection equipment, and particularly relates to a double-effect biological rotating disc device and a process for treating wastewater. BACKGROUND

[0002] The biological membrane method is a kind of wastewater aerobic biological treatment technology, and the biological rotating disc water treatment device as a kind of biological membrane method wastewater treatment device has been widely applied to the treatment of domestic wastewater, landfill leachate and industrial wastewater. The biological rotating disc water treatment device is generally composed of a reaction tank and a biological rotating disc device arranged above the reaction tank. The biological rotating disc device comprises a rotating shaft and a biological rotating disc device arranged on the outer periphery of the rotating shaft and rotating with the rotating shaft. The disc-shaped biological membrane sheet part of the biological rotating disc device is partially immersed in the wastewater in the water tank. Microorganisms attached to the disc-shaped biological membrane sheet form a biological membrane on the disc-shaped biological membrane sheet to degrade organic matter in the wastewater, thereby achieving the purpose of purification.

[0003] With the increasing amount of wastewater in modern enterprises, the water treated by the original biological rotating disc device of the old wastewater treatment plant cannot meet the gradually increasing total nitrogen and total phosphorus indicators. If new devices are introduced, a large amount of funds will be consumed. Therefore, it is urgent to modify the original device. Meanwhile, after long-term operation of the biological rotating disc device, the biological membrane hung on the disc-shaped biological membrane sheet will continuously attach and thicken, thereby causing the device to run under heavy load. The maximum bending moment is borne by the middle part of the rotating shaft, and the inner disc plate weld at the middle part of the rotating shaft is prone to fracture. SUMMARY

[0004] In view of the above-mentioned problems that the water treated by the original biological rotating disc device of the old wastewater treatment plant cannot meet the gradually increasing total nitrogen and total phosphorus indicators, and the middle part of the rotating shaft bears the maximum bending moment and is prone to fracture, the present application provides a biological rotating disc device. The device is modified from the original device, and a grid net is arranged at the outer edge of the inner disc plate to form a rotating cage. The device can avoid the fracture of the middle part of the rotating shaft and the weld at the inner disc plate. The biological rotating disc device on both sides of the device continuously works under aerobic / anaerobic reaction, and the spherical biological membrane filler added in the middle rotating cage continuously works under anaerobic reaction. Therefore, nitrate nitrogen and organic phosphorus can be effectively removed, and double effects can be achieved.

[0005] The technical scheme and beneficial effects of the present application are as follows:

[0006] A double-effect biological rotating disc device comprises a rotating shaft, an inner disc plate fixed to the outer periphery of the middle part of the rotating shaft, and an outer disc plate fixed to the outer periphery of both ends of the rotating shaft. A plurality of biological membrane sheets are arranged between the inner disc plate and the outer disc plate. A grid net is arranged between two adjacent inner disc plates to form a cylindrical rotating cage. Biological membrane fillers can be placed in the rotating cage.

[0007] As a further improvement of the above technical scheme:

[0008] The biofilm sheet is disc-shaped.

[0009] The biofilm filler is spherical.

[0010] The biofilm sheet and the biofilm filler are both made of a mesh structure of polyvinylidene chloride material.

[0011] A process for treating sewage using the double-effect bio-teller device of claim 1, the bio-teller device being erected above a reaction tank or a sewage tank and continuously rotating, the biofilm sheet between the inner disc sheet and the outer disc sheet being partially in contact with the sewage, the biofilm sheet forming an anoxic condition under water, an aerobic condition above water, an anoxic condition inside the biofilm sheet and an aerobic condition outside the biofilm sheet through rotation, and the surface of the biofilm sheet being attached with facultative microorganisms; the biofilm filler in the rotating cage rolling and sinking at the bottom of the rotating cage as the bio-teller device rotates, so that the biofilm filler is continuously in an anoxic state, and the surface of the biofilm filler being attached with anoxic microorganisms; and the sewage being biologically treated by the facultative microorganisms and the anoxic microorganisms.

[0012] As a further improvement of the above technical solution:

[0013] The facultative microorganisms attached to the surface of the biofilm sheet are bacillus.

[0014] The anoxic microorganisms attached to the surface of the biofilm filler are denitrifying bacteria or denitrifying phosphorus bacteria.

[0015] The bio-teller device of the present application has disc-shaped biofilm sheets partially in contact with sewage and spherical biofilm fillers immersed in the sewage, the disc-shaped biofilm sheets forming an anoxic condition under water, an aerobic condition above water, an anoxic condition inside the biofilm sheet and an aerobic condition outside the biofilm sheet, which is conducive to the enrichment of facultative microorganisms such as bacillus. A rotating cage is arranged at the center of the rotating shaft to ensure that the spherical biofilm fillers rotate with the rotating cage and sink at the bottom of the rotating cage, so that the spherical biofilm fillers are continuously in an anoxic state, which is conducive to the enrichment of anoxic microorganisms such as denitrifying bacteria and denitrifying phosphorus bacteria on the surface of the spherical biofilm fillers, so that nitrate nitrogen and organic phosphorus can be effectively removed. A grid net is arranged at the outer edge of the original inner disc sheet of the rotating shaft to form the rotating cage, which can facilitate the modification of the bio-teller device and is suitable for sewage treatment plants that need to be modified in situ. Meanwhile, the grid net connected between the central part of the rotating shaft and the inner disc sheet can also play a reinforcing role to avoid the fracture at the weld of the inner disc sheet in the central part of the rotating shaft. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 FIG. 1 is a structural schematic view of the bio-teller device of the present application erected on a reaction tank; (biofilm sheet not installed)

[0017] Figure 2 FIG. 2 is a front view of the bio-teller device of the present application erected on a reaction tank; (biofilm sheet not installed)

[0018] Figure 3 Figure 2 is a top view of the biological membrane piece installed on the biological rotating disc device frame of the present application; (installation of biological membrane piece and biological membrane filler)

[0019] Figure 4 Figure 3 is a structural schematic view of the biological rotating disc device of the present application.

[0020] In the figure: 1, reaction tank; 2, speed reducer; 3, biological rotating disc device; 31, rotating shaft; 32, outer disc piece; 33, inner disc piece; 34, biological membrane piece; 4, rotating cage; 5, grid net; 6, biological membrane filler. DETAILED DESCRIPTION

[0021] The specific embodiment of the present application is described below in combination with the accompanying drawings.

[0022] As shown in Figures 1-4 Figure 2, the biological rotating disc device 3 of the present application is erected above the reaction tank 1, and includes a rotating shaft 31, two outer disc pieces 32 fixed at both ends of the rotating shaft 31, and two inner disc pieces 33 fixed at the middle part of the rotating shaft 31. One end of the rotating shaft 31 is connected with and driven to rotate by the speed reducer 2 fixed at one side of the reaction tank 1. The outer disc pieces 32 and the inner disc pieces 33 divide the rotating shaft 31 into a three-section structure.

[0023] Two groups of biological membrane pieces 34 (see Figure 3 ) are arranged between the outer disc pieces 32 and the inner disc pieces 33. In this embodiment, the biological membrane pieces 34 are disc-shaped. When the disc-shaped biological membrane pieces 34 rotate with the rotating shaft 31, since the sewage in the reaction tank 1 is located below the rotating shaft 31, 40% of the area at the bottom of the disc-shaped biological membrane pieces 34 is in contact with the sewage. The disc-shaped biological membrane pieces 34 adopt a special net-like structure of polyvinylidene chloride material. Therefore, the disc-shaped biological membrane pieces 34 form an anoxic condition under water, an aerobic condition above water, an anoxic condition inside the membrane, and an aerobic condition outside the membrane, which is beneficial to the enrichment of spore bacillus-type facultative microorganisms.

[0024] The outer edges of the two inner disc pieces 33 are connected with a grid net 5, so that the inner disc pieces 33 and the grid net 5 enclose a cylindrical rotating cage 4. The grid net 5 can play a reinforcing role to avoid the breakage of the middle part of the rotating shaft 31 due to the large bending moment borne by the middle part of the rotating shaft 31. The biological membrane filler 6 is put into the rotating cage 4. In this embodiment, the biological membrane filler 6 is spherical. When the biological rotating disc device 3 rotates, the spherical biological membrane filler 6 rolls together with the rotating cage 4 due to the influence of gravity, so that it can be kept sinking at the bottom of the rotating cage 4 and continuously in contact with the sewage, i.e., continuously in an anoxic state to occur an anaerobic reaction. The biological membrane filler 6 also adopts a special net-like structure of polyvinylidene chloride material, which is beneficial to the enrichment of anoxic microorganisms such as denitrifying bacteria and denitrifying phosphorus bacteria on the surface of the biological membrane filler 6, so that nitrate nitrogen and organic phosphorus can be effectively removed.

[0025] In actual use, the pre-processed sewage enters the biological rotating disc water treatment device, the speed reducer 2 drives the biological rotating disc device 3 to rotate, the disc-shaped biological membrane piece 34 is in contact with the sewage when rotating, the spherical biological membrane filler 6 keeps in contact with the sewage, the surfaces of the disc-shaped biological membrane piece 34 and the spherical biological membrane filler 6 are hung with microorganisms, so that the simultaneous nitrification and denitrification process is realized in the biological rotating disc water treatment device, and organic matter, ammonia nitrogen, total nitrogen and total phosphorus are effectively removed. Thus, the dual-effect function of aerobic-anaerobic reaction and anaerobic reaction is realized in the same biological rotating disc water treatment device.

[0026] The above description is an explanation of the present application, not a limitation of the present application, and the present application can be modified in any form without departing from the spirit of the present application, for example, the biological rotating disc device 3 can also be directly erected above any sewage pool.

Claims

1. A double-effect biological rotating disc device, comprising a rotating shaft (31), an inner disc (33) fixed to the outer periphery of the middle part of the rotating shaft (31), an outer disc (32) fixed to the outer periphery of both ends of the rotating shaft (31), and a plurality of biological membranes (34) between the inner disc (33) and the outer disc (32), characterized in that: The adjacent two inner discs (33) are provided with a grid (5) to form a cylindrical rotating cage (4), and the biological membrane filler (6) can be put into the rotating cage (4). The biological membrane filler (6) in the rotating cage (4) rolls and sinks at the bottom of the rotating cage (4) with the rotation of the biological rotating disc device (3), so that the biological membrane filler (6) is in an anoxic state continuously. ​ 2. The dual purpose biological disk apparatus according to claim 1, wherein: The biological membrane sheet (34) is disc-shaped.

3. The dual purpose biological rotary disc apparatus as claimed in claim 1, wherein: The biological membrane filler (6) is spherical.

4. The dual purpose biological tray apparatus as claimed in claim 1, wherein: The biological membrane sheet (34) and the biological membrane filler (6) are both in a mesh structure of polyvinylidene chloride material.

5. A process for treating sewage using the double-effect biological rotating disc device according to claim 1, wherein the biological rotating disc device (3) is installed above the reaction tank (1) or the sewage tank and continuously rotates, characterized in that: The biological membrane sheet (34) between the inner disc (33) and the outer disc (32) partially contacts with sewage, and the biological membrane sheet (34) forms an anoxic condition under water, an aerobic condition above water, an anoxic condition in the membrane, and an aerobic condition outside the membrane through rotation, and the surface of the biological membrane sheet (34) is attached with facultative microorganisms; the surface of the biological membrane filler (6) is attached with anoxic microorganisms; and the sewage is biologically treated by the facultative microorganisms and the anoxic microorganisms.

6. A process for treating sewage according to claim 5, characterised in that: The facultative microorganisms attached to the surface of the biological membrane sheet (34) are bacillus.

7. A process for treating sewage according to claim 5, characterised in that: The anoxic microorganisms attached to the surface of the biological membrane filler (6) are denitrifying bacteria or denitrifying phosphorus bacteria.

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