JPH04118198U - Sewage septic tank - Google Patents

Abstract

(57) [Summary] (with amendments) [Purpose] A sewage septic tank that is compact but has the same purification efficiency as a separate tertiary treatment tank and also has superior denitrification efficiency, mainly for use in tanks for 5 to 30 people. The purpose is to improve. [Configuration] It has an anaerobic filter bed tank first chamber 2A and a second chamber 2B, a contact aeration tank first chamber 3A and a second chamber 3B, a sedimentation tank 4 and a disinfection tank 5, and the contact aeration tank Circulation pump 6 that constantly returns the tank liquid in the tank first chamber 3A to the anaerobic filter bed tank first chamber 2A
A and a circulation pump 6B that irregularly returns the tank liquid in the contact aeration tank second chamber 3B to the anaerobic filter bed tank first chamber 2A, and the liquid generated in the contact aeration tank first chamber 3A is By constantly returning the peeled sludge to the anaerobic filter bed tank first chamber 2A, the load is reduced and the purification efficiency is increased.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This idea is related to sewage septic tanks, and more specifically, improvement of sewage septic tanks with tertiary treatment tanks. Regarding.

0002

[Conventional technology]

Traditionally, sewage septic tanks are used to treat sewage through biological treatment by anaerobic microorganisms and aerobic microorganisms. A system that sequentially purifies wastewater through action is widely known, and this method is usually used. These sewage septic tanks are classified into tanks for 5 to 30 people, or tanks for 31 people or more depending on their structure. ing. In the above, sewage septic tanks with a capacity of 5 to 30 people are usually anaerobic filter beds. It has a structure that integrates the first chamber, the second chamber, a contact aeration tank, a sedimentation tank, and a disinfection tank. , the discharge standards are set so that the BOD of the purified water that is finally discharged is 20 mg/l or less. It is determined. The target water quality of purified water must be BOD 10 mg/l or less, which is stricter than the above standards. If required, a tertiary sewage treatment tank should be installed in addition to the above sewage septic tank, and these should be connected. It is said that the structure is designed to treat sewage depending on the structure (for example, Utility Model Application No. 1-147524; 7526, 149541 specification and drawings, etc.).

0003

[Problems with conventional technology]

However, after installing the sewage septic tank mentioned above, It is necessary to install a separate tertiary treatment tank while adjusting the This also has the disadvantage of requiring a large installation area. Furthermore, since the tertiary treatment tank is separate from the main sewage septic tank, the tertiary treatment To return the liquid in the tank to the main sewage septic tank, a return head with a higher water level than the front tank is used. A feed pump is required, and air lift pumps require a large amount of air and are inefficient. won.

0004

[Problem that the idea aims to solve]

In view of the above problems, this idea was designed to be compact but equipped with a tertiary treatment tank. It is mainly used for tanks with 5 to 30 people, and has a purification efficiency equivalent to that of The purpose is to improve sewage septic tanks.

[0005]

[Means to solve the problem]

That is, the sewage septic tank of this invention has a first chamber of the anaerobic filter bed tank into which sewage flows, and a chamber below. Anaerobic filter bed tank 2nd room, contact aeration tank 1st room and 2nd room where the water is naturally advected It has a chamber, a sedimentation tank, and a disinfection tank, and the liquid in the first chamber of the contact aeration tank is constantly abated. A circulation pump that returns the liquid to the first chamber of the air filter bed tank and a tank liquid that returns the liquid in the second chamber of the contact aeration tank. It is characterized by being equipped with a circulation pump that periodically returns the water to the first chamber of the anaerobic filter bed tank. It is something to do.

[0006]

【Example】

Next, an example of this invention will be described. FIG. 1 is a sectional view of an embodiment of this invention. The sewage septic tank 1 of this invention consists of an anaerobic filter bed tank first chamber 2A into which sewage flows, and a Anaerobic filter bed tank second chamber 2B, contact aeration tank first chamber 3A, where water is naturally advected in sequence It has the same second chamber 3B, sedimentation tank 4 and disinfection tank 5 as one unit, and a contact aeration tank first chamber 3A. A circulation pump 6A is provided to constantly return the liquid in the tank to the first chamber of the anaerobic filter bed tank. In addition, the tank liquid in the contact aeration tank second chamber 3B is returned to the anaerobic filter bed tank first chamber at irregular intervals. A circulation pump 6B is provided. In the above, air lift pumps are used as the circulation pumps 6A and 6B, and In order to adjust the flow rate, there is an orifice plate etc. in the air supply pipe to the air lift pump 6A. An adjusting device consisting of: In addition, 7A and 7B in the figure indicate backwashing of the contact material in the first and second chambers of the contact aeration tank, respectively. The air diffusers 8A and 8B are used to diffuse air into the first and second chambers of the contact aeration tank, respectively. Showing the diffuser tube. Also, the return circulation pump 6B of the contact aeration tank second chamber 3B is not shown, but It is configured to be driven and operated intermittently by a marketing device or the like.

[0007]

[Effect]

In the sewage septic tank 1 of this invention, sewage flows into the anaerobic filter bed tank first chamber 2A, Naturally transferred sequentially to anaerobic filter bed tank second chamber 2B, contact aeration tank first chamber 3A, and second chamber 3B. It is purified while being advected by the current. In this case, coarse suspended matter is removed from the inflow water in the first chamber 2A and second chamber 2B of the anaerobic filter bed tank. and decomposed by the action of anaerobic microorganisms. Next, go to the contact aeration tank first chamber 3A. When advected, organic matter and ammonia in the water are oxidized and decomposed by the action of aerobic microorganisms. , the same treatment is carried out in the second chamber 3B of the contact aeration tank, and the BOD value further decreases, resulting in nitrification. progresses. If this treatment process continues for a long time, a biofilm of microorganisms will form in the first chamber 3A of the contact aeration tank. The liquid will peel off and become suspended in the tank, but the liquid in the tank will be constantly circulated through the anaerobic filter bed tank by the circulation pump 6. Since the water is returned to the first chamber, the detached biofilm is returned and contacted by this water flow. Increase in the aeration tank first chamber 3A is prevented. Therefore, the load of advective organic matter in the first chamber 3A of the contact aeration tank is kept low, and henceforth Stable BOD removal is possible even in the contact aeration tank second chamber 3B, making it easy to remove BOD. ≦10ppm is achieved, and the nitrification efficiency is further improved. In addition, it is possible to constantly return nitrifying liquid from the first chamber of the contact aeration tank and intermittent return from the second chamber. In the anaerobic filter bed tank, chamber escape progresses. Furthermore, since the contact aeration tank first chamber 3A and the second chamber 3B are integrated, advection The level difference between the two can be reduced.

[0008]

[Effect of the idea]

As explained above, this idea integrates the tertiary treatment tank, which was previously separated. As a result, the volume is extremely compact, achieving a miniaturization of the tank for 5 to 30 people. This eliminates the need for long advection pipes that were previously required, and allows the bottom of the discharge pipe to be designed shallower. This reduces installation restrictions and makes installation work easier. In addition, the treated water is constantly returned from the first room of the contact aeration tank to the first room of the anaerobic tank, and the contact aeration tank is Intermittent return from the second chamber of the tank stabilizes water quality by reducing BOD and neutralizing pH. Furthermore, the denitrification efficiency is also good, and BOD≦10PPm due to treatment in the second chamber of the contact aeration tank. , it becomes possible to obtain very good purified water such as T-N≦20PPm.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an embodiment of the invention.

[Explanation of symbols]

1 Sewage septic tank 2A Anaerobic filter bed tank first room 2B Anaerobic filter bed tank second chamber 3A Contact aeration tank first chamber 3B Contact aeration tank second chamber 4 Sedimentation tank 5 Disinfection tank 6 Circulation pump

──────────────────────────────────────────────── ─── Continuation of front page (72) Creator Dai Harada 2-1 Takamatsu, Kosai-machi, Koka-gun, Shiga Prefecture Stocks Inside Kubota Shiga Factory (72) Creator Kazuyuki Honda 2-1 Takamatsu, Kosai-machi, Koka-gun, Shiga Prefecture Stocks Inside Kubota Shiga Factory

Claims (1)

[Scope of utility model registration request] Claim 1: A first chamber of the anaerobic filter bed tank into which sewage flows, and a second chamber of the anaerobic filter bed tank into which the treated water is sequentially naturally advected;
A circulation pump that integrally includes a first chamber and a second chamber of a contact aeration tank, a settling tank, and a disinfection tank, and constantly returns the tank liquid in the first chamber of the contact aeration tank to the first chamber of an anaerobic filter bed tank. and a circulation pump for irregularly returning the liquid in the tank in the second chamber of the contact aeration tank to the first chamber of the anaerobic filter bed tank.