JPH0544293U - Septic tank - Google Patents

Abstract

(57) [Summary] [Structure] A settling tank 1 for settling sludge in the treated water from the contact aeration tank E on the upstream side, and a disinfecting tank 2 for disinfecting the supernatant liquid from the settling tank 1 are provided. In a septic tank in which a chemical pipe 8 for dissolving a solid disinfectant in treatment water is erected at the junction of the left and right crossover channels 6 into the disinfection tank 2, the junction is defined as the junction of the overflow channels 6. Is formed deeper than the upstream side and the downstream side. [Effect] The dissolution efficiency of the disinfectant can be improved. As a result, for example, the inflow of treated water decreases,
Even if the temperature may drop, the disinfectant concentration of the treated water to be discharged can always reach a predetermined concentration.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention comprises a settling tank for settling sludge in the treated water from the upstream side, and a disinfecting tank for disinfecting the supernatant liquid from the settling tank. , A septic tank in which a chemical cylinder for vertically dissolving a solid disinfectant in treated water is installed.

[0002]

[Prior Art]

 In the conventional septic tank, the merging portion of the overflow passage in which the medicine cylinder is vertically arranged is set to the same depth as the upstream side and the downstream side of the merging portion in the overflow passage. However, since the flow rate of the treated water flowing into the septic tank fluctuates, in such a configuration, for example, if the flow rate of the treated water decreases, the depth of the treated water flowing through the overflow channel will become shallow as a whole. In some cases, the solid disinfectant contained in the chemical cylinder standingly installed at the confluence of the overflow channel cannot maintain a sufficient contact area with the treated water. As a result, the amount of disinfectant dissolved was insufficient, and the concentration of the disinfectant in the treated water to be discharged could not reach the prescribed disinfectant concentration. Further, for example, the temperature of the treated water changes depending on the season, the dissolution speed of the disinfectant decreases in winter, and the disinfectant dissolved in the treated water may not reach a predetermined concentration.

[0003]

[Problems to be solved by the device]

 Therefore, an object of the present invention is to ensure that the disinfectant concentration of the treated water to be discharged always reaches a predetermined concentration, even if the inflow amount of the treated water is decreased or the temperature is lowered. It is to provide a septic tank that can.

[0004]

[Means for Solving the Problems]

 To achieve this purpose, the septic tank according to the present invention is characterized by a settling tank for settling sludge in the treated water from the upstream side and a disinfecting tank for disinfecting the supernatant liquid from the settling tank. A chemical pipe for dissolving a solid disinfectant in the treatment water is erected at the confluence of the left and right overflow passages to the disinfection tank, and the confluence is connected to the junction of the overflow passage. It is formed deeper than the upstream side and the downstream side.

[0005]

[Action]

 By forming the merging portion in which the drug cylinder is erected and arranged deeper than the upstream side and the downstream side of the merging portion in the overflow channel, the merging portion has the same depth as the upstream side and the downstream side. It is possible to always keep the state in which the chemical cylinder is immersed deeper in the processing liquid than in the case of the conventional configuration. As a result, even if the inflow of treated water fluctuates and may decrease, the solid disinfectant contained in the chemical cylinder can always be in sufficient contact with the treated water to dissolve it. .

[0006]

[Effect of the device]

 That is, the dissolution efficiency of the solid disinfectant can be improved by a simple improvement in which the confluence portion is formed deep and the medicine cylinder is erected there. As a result, for example, even if the inflow of treated water decreases or the temperature drops, a septic tank that can ensure that the disinfectant concentration of the treated water to be discharged reaches a prescribed concentration at all times. Could be provided.

[0007]

【Example】

 An embodiment of a septic tank according to the present invention will be described below with reference to the drawings. As shown in Fig. 1, this septic tank is composed of a settling tank 1 for settling and separating sludge in the treated water that is transferred from the bottom of the contact aeration tank E on the upstream side, and a disinfection for disinfecting the supernatant liquid transferred from the settling tank 1. Equipped with a discharge water storage tank 3 for receiving treated water from the tank 2 and the disinfection tank 2 once, retaining it, mixing and discharging it, and a discharge pump 5 for discharging the treated water in the discharge water storage tank 3 through a discharge pipe 4. ing. As shown in FIGS. 1 to 4, the depth of the confluence portion of the left and right crossover channels 6 from the settling tank 1 to the disinfection tank 2 is deeper than the upstream and downstream sides of the confluence portion 6 in the overflow channel 6. The drug cylinder 8 is formed upright in the vicinity of the center of the merging portion. The width of the merging portion is formed wider than the diameter of the medicine tube 8. A solid disinfectant is housed in the medicine barrel 8, and a plurality of long and narrow treated water flows in and out over the entire circumference of the peripheral surface near the bottom of the medicine barrel 8 so that the disinfectant comes into contact with and dissolves in the treated water. A hole is formed. The supernatant liquid of the settling tank 2 overflows into the overflow channel 6 from a plurality of V notches formed in the left and right overflow weirs 9 and contacts the disinfectant in the medicine tube 8 at the junction to dissolve the disinfectant. However, it is designed to flow into the disinfection tank 2. The disinfectant tank 2 is provided with a partition wall 10 while ensuring a flow path at the bottom so that the dissolved disinfectant is well mixed with the treated water, so that the treated water flowing into the disinfectant tank 2 does not short-circuit. It passes under 10 and overflows from the overflow port 11 to the discharged water storage tank 3. As shown in FIG. 1, the discharge water storage tank 3 uses a float 12 to automatically manage the water level, and when the water level rises to the upper limit water level HWL, the discharge pump 5 operates and the discharge pipe 4 is used. When the treated water is discharged and the water level drops to the lower limit water level LWL, the discharge pump is stopped. The capacity of the discharge pump 5 is set to be larger than the amount of treated water flowing into the septic tank, and a part of the treated water pumped by the discharge pump is returned to the discharge storage tank via the circulation path 14 so that the treated water in the discharge water storage tank is It is mixed well and the temporal and spatial variation of the disinfectant concentration of the treated water is controlled as much as possible. The upper limit water level HWL is set lower than the overflow port 11, and the overflow port 11 is provided at a level lower than the outlet of the overflow channel 6. Reference numeral 15 in the figure is a flow rate adjusting valve for adjusting the apparent pump capacity of the discharge pump 5 by adjusting the flow rate of the circulating water. As the solid disinfectant, for example, an isocyanuric acid organic chlorine agent having a high effective chlorine content can be used. Compared to widely used calcium hypochlorite, this disinfectant does not easily swell even when immersed in treated water, so even if the lower part of the drug contained in the drug cylinder dissolves in the treated water, It is excellent in that it does not cause the so-called bridging phenomenon in which the chemical swells and does not fall to the bottom.However, since the dissolution rate is low, conventional septic tanks are subject to fluctuations in the inflow rate of treated water, etc. There was a risk that the disinfectant concentration of the treated water would not reach the prescribed concentration. However, according to the above configuration, while the solid disinfectant can be used to eliminate the bridge phenomenon, for example, the disinfectant for treated water does not change even if the amount of treated water flowing into the septic tank varies. It is possible for the concentration to always reach a predetermined concentration.

It should be noted that reference numerals are added to the claims of the utility model for convenience of comparison with the drawings, but the invention is not limited to the configurations of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a main part of a septic tank according to an embodiment.

FIG. 2 is a perspective view near the overflow channel.

FIG. 3 is a cross-sectional view near the confluence of the overflow channel.

FIG. 4 is a vertical cross-sectional view near the confluence of the overflow channel.

[Explanation of symbols]

 1 settling tank 2 disinfection tank 6 overflow channel 8 chemical tube

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Yoshito Kitai, 1 person at Takamatsu, Kosai-cho, Koga-gun, Shiga Prefecture, Kubota Shiga Plant (72) Inventor, Kazuyuki Honda, Takamatsu, Kosai-cho, Koga-gun, Shiga Prefecture 1 Inside the Kubota Shiga factory

Claims (1)

[Scope of utility model registration request] 1. A settling tank (1) for settling sludge in treated water from the upstream side, and a disinfecting tank (2) for disinfecting a supernatant liquid from the settling tank (1), comprising: A septic tank in which a chemical pipe (8) for dissolving a solid disinfectant in treatment water is erected at the confluence of the left and right cross-flow channels (6) to the disinfection tank (2). Is formed deeper than the upstream side and the downstream side of the merging portion in the overflow channel (6).