JPS632240B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention uses a cylindrical shape to purify miscellaneous wastewater such as industrial wastewater discharged from various factories, room sewage from hotels, inns, restaurants, etc., bathroom sewage, laundry sewage, etc. A large number of activated sludge beds formed by winding porous air bodies around the outer periphery of a core body are fixed upright in a sewage treatment tank, and air aeration is performed from the bottom to bring fine air bubbles into contact with the activated sludge beds. For example, aerobic bacteria and anaerobic bacteria adhere to, culture, and proliferate within the pores of the porous air body of the activated sludge bed, and these bacteria oxidize and decompose BOD and COD in the sewage. This invention relates to a sewage treatment method using an activated sludge bed that ingests bacteria and anaerobic bacteria to cause self-digestion and purify the sewage without generating excess sludge.

Conventional sewage treatment methods include the standard activated sludge method, the diffused filter bed method, and the coagulation sedimentation/filtration method.
The installation of these treatment facilities requires a large amount of money and space, and sewage treatment management requires highly skilled technology and periodic inspections. Since excess sludge must be disposed of, cleaning costs are also high.

There is also a microbial membrane method that uses aerobic microorganisms such as BOD and COD in sewage to purify mud beds.
This method oxidizes, decomposes, and removes BOD and COD through the action of aerobic microorganisms by bringing sewage into contact with a thin microbial film that adheres to the surface of the contact material along with air bubbles. The material used is corrugated hard synthetic resin or sponge sections. However, among these contact materials, the former is a smooth synthetic resin plate, so it takes a long time for aerobic microorganisms to attach and culture.
Furthermore, since these aerobic microorganisms are simply attached to the surface of the corrugated plate, their holding power is weak, and if the aerobic microorganisms multiply more than necessary or impact is applied to the contact material, they will easily fall off, resulting in excess sludge. As a result, the purification ability decreases. On the other hand, in the latter case, the sponge sections have an excellent retention power because aerobic microorganisms adhere to their pores, but on the other hand, the sponge sections themselves are not dispersed throughout the sewage treatment tank due to air aeration, and the sewage water due to air aeration is It moves to one corner of the treatment tank due to current or wind force, making it impossible to perform uniform purification treatment.

In the present invention, a large number of activated sludge beds formed by winding a porous air body of a certain thickness around a cylindrical core are fixed upright in the sewage of a sewage treatment tank, and air aeration is performed from below. The activated sludge bed does not move due to the air bubbles ejected from the pipe, and the countless air bubbles rise while contacting both the inner and outer peripheral surfaces of the cylindrical activated sludge bed, preventing aerobic and anaerobic bacteria from entering the porous gaseous body. It is preferable because the adhesion and cultivation of aerobic bacteria can be carried out in a short time, and in addition, aerobic bacteria adhere closely to the pores of a porous material such as vinylidene chloride or spongy resin, so the adhesion force is excellent. Aerobic bacteria oxidize, decompose, and remove BOD and COD without worrying about peeling off, and giant microorganisms that feed on aerobic and anaerobic bacteria naturally occur in the center of this porous air body, spreading from the inside to the inner and outer surfaces. It infiltrates the aerobic and anaerobic bacteria in the area and causes autolysis, prevents the excessive growth of aerobic bacteria, eliminates the generation of excess sludge, and when a certain limit is reached, both are balanced and an equilibrium state is reached. It exhibits stable sewage treatment capacity.

To explain this with an example, a porous gaseous material 2 such as vinylidene chloride or spongy resin and a mesh or fibrous resin of a constant thickness is wound around the outer periphery of a cylindrical core body 1 which is elongated and formed into a mesh shape. A large number of activated sludge beds 4, which are formed by rotating and attaching long-term indestructible fixing bands 3, 3' to the outer periphery thereof, are fixed upright in the sewage of the sewage treatment tank 5. Air aeration is performed using an air aeration pipe 6 piped on the bottom, and the wastewater is made to flow using a pump 7 or the like to form aerobic bacteria 8 on the surface layer of the outer circumferential surface of the activated sludge bed 4 and on the surface layer of the inner circumferential surface. Anaerobic bacteria 9 are attached, cultured, and multiplied to oxidize and decompose BOD and COD in the wastewater, and at the same time, Zoglaea bacteria, Spharotails, Nematoda, water mites, etc. naturally occur in the center of the porous air body 2. The giant microorganisms 9' infiltrate aerobic bacteria 8 and anaerobic bacteria 9, causing self-digestion and purifying wastewater without generating excess sludge. 10 is a fixed cover, 11 is a fixed ring, and 12 is a fixed rod.

The present invention is constructed as described above, and the cylindrical core body 1 forming the activated sludge bed 4 is made of hard synthetic resin or the like that does not undergo corrosion deterioration even when immersed in waste water for a long period of time. The porous gas material 2 wound around the outer circumference of the porous gas material 2 is made of highly corrosion-resistant vinylidene chloride or A material of a certain thickness such as spongy resin, mesh or fibrous resin is used, and the thickness should be within 20 m/m depending on the concentration of wastewater, but normally if a material of around 15 m/m is used, aerobic bacteria8 and anaerobic bacteria8 The bacteria 9 are infiltrated by the giant microorganisms 9' and retained in a well-balanced manner, resulting in self-digestion and no peeling due to generation of excess sludge.

A large number of activated sludge beds 4 thus formed are installed in close proximity to the sewage in the sewage treatment tank 5, and a certain amount of air bubbles are ejected from the air aeration pipe 6 piped downward, and the sludge flows into the sewage. By imparting this property, aerobic bacteria 8 and anaerobic bacteria 9 adhere to the pores in the surface layer on both the inner and outer surfaces of the activated sludge bed 4, grow in culture, and eliminate BOD and COD in the sewage. Along with oxidative decomposition and removal, giant microorganisms 9' such as Zoglaea, Spharotails, Nematoda, and water mites naturally occur in the center of the porous air body 2, resulting in aged aerobic bacteria 8 and anaerobic bacteria 9 with poor purification efficiency. The activated sludge bed 4 is devoured from the inside to cause self-digestion, and a large amount of aerobic bacteria 8 and anaerobic bacteria 9 are always kept at a constant thickness to eliminate the generation of excess sludge. Newer aerobic bacteria 8 and anaerobic bacteria 9 with high purification efficiency are constantly cultured and proliferated on the surface to purify the wastewater.

An example of the use of the present invention is to explain the sewage treatment process using consecutive sewage treatment tanks based on FIG. 15, 16, 17 are provided, and a flow path 18,
19, 20, and 21, and the above-mentioned activated sludge bed 4 and air aeration pipe 6 are provided in each of the sewage treatment tanks 14, 15, 16, and 17, and the treated raw water is transferred from the flow rate adjustment tank 13 to each sewage. Processing tank 14, 15, 1
When performing purification treatment through steps 6 and 17, the optimum aerobic bacteria 8 in each sewage treatment tank 14, 15, 16, 17
The ratio of aerobic bacteria and anaerobic bacteria 9 is 80% aerobic bacteria and 20% anaerobic bacteria in the first sewage treatment tank 14, 60% aerobic bacteria and 40% anaerobic bacteria in the second sewage treatment tank 15, Third
Inside the sewage treatment tank 16, there are 50% aerobic bacteria and 50% anaerobic bacteria.
% and aerobic bacteria (40
%), 60% of anaerobic bacteria and, for example, assuming that the treated raw water flowing into the first sewage treatment tank 14 is 2500 ppm, the appropriate dissolved oxygen value (hereinafter referred to as DO value) ejected from the air aeration pipe 6 is 4.6 ppm. Then, the DO value of aerobic bacteria 8 in the activated sludge bed 4 of the same tank is 3.68 ppm, the DO value of anaerobic bacteria 9 is 0.9 ppm, and the treated water in the first sewage treatment tank 14 is 980 ppm. It flows into the second sewage treatment tank 15, and similarly the DO value of the same tank is 3.9ppm.
Then, the DO value of aerobic bacteria 8 is 2.34 ppm, the DO value of anaerobic bacteria 9 is 1.56 ppm, and the sewage can be treated to 490 ppm and flows into the third sewage treatment tank 16.
Similarly, if the DO value of the treatment tank 16 is 3.2ppm,
The DO value of aerobic bacteria 8 is 1.6 ppm, and the DO value of anaerobic bacteria 9
The value is 1.6ppm, and the sewage is treated to 200ppm and flows into the fourth sewage treatment tank 17, and the DO of the same treatment tank 17 is further reduced.
If the value is 1.3ppm, the DO value of aerobic bacteria 8 is
0.52ppm, the DO value of anaerobic bacteria 9 is 0.78ppm, and at the final stage when it is discharged from the 4th sewage treatment tank 17, it is less than 3ppm or BOD and COD are not detected (ND)
The water becomes purified water, and as the continuous state of the sewage treatment tank is changed as appropriate, the amount of water to each treatment tank is changed.
By changing the DO value, the aerobic bacteria 8 and anaerobic bacteria 9 in the activated sludge bed 4 can live in a well-balanced manner, allowing for proper purification without generating excess sludge.

[Brief explanation of the drawing]

Fig. 1 is a slope view of the activated sludge bed according to the present invention, Fig. 2 is an enlarged cutaway view of the same part, and Fig. 3 is a diagram of the activated sludge bed when aerobic bacteria and anaerobic bacteria are attached and cultured. FIG. 4 is a sectional view of an example of use of the present invention, and FIG. 5 is a sectional view of another example of use. In the figure, 1... Core body, 2... Porous gaseous body, 3,
3'... Fixed band, 4... Activated sludge bed, 5...
Sewage treatment tank, 6... Air aeration pipe, 8... Aerobic bacteria, 9... Anaerobic bacteria, 9'... Giant microorganisms.

Claims (1)

[Claims] 1. A porous gas material such as vinylidene chloride or spongy resin of a certain thickness and a mesh or fibrous resin is wound around the outer periphery of a cylindrical core formed into a slender mesh shape, and a long-term immortal material is wound around the outer periphery of the core. A large number of activated sludge beds formed by attaching fixing bands as appropriate are fixed upright in the sewage of the sewage treatment tank, and air aeration is performed from an air aeration pipe piped above the inner bottom of the sewage treatment tank.
Sewage is made to flow using a pump, etc., and aerobic bacteria are attached to the surface layer of the outer surface of the activated sludge bed, and anaerobic bacteria are attached to the surface layer of the inner surface of the activated sludge bed, cultured, and multiplied. In addition to oxidizing and decomposing COD, giant microorganisms such as Zoglaea, Spharotails, Nematoda, and water mites that naturally occur in the center of the porous gaseous body infiltrate aerobic and anaerobic bacteria, causing self-digestion. A sewage treatment method using an activated sludge bed that purifies sewage without generating excess sludge.