JP2002180527A - Vacuum type sewerage system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To carry sewage to the downstream across obstacles without creating a lift loss by using a simple construction. SOLUTION: A water collecting tank 1 is installed at the upstream of an obstacle S, the upstream vacuum sewer pipeline 2 is connected through a check valve 10, and a communicating pipe 6 arranged with an automatic suction valve 8 performing opening and closing operation by interlocking with the vacuum pressure is connected. Also, a downstream vacuum sewer pipeline 3 is arranged at the downstream of the obstacle S, and a pervious pipe 4 crossing the obstacle S is connected between the vacuum sewer pipeline 3 at the downstream 3 and the collecting tank 1. In addition, between the upstream side vacuum sewer pipeline 2 and the downstream sewer pipe line 3, an equalizing pipe 5 arranged with a check valve 7 permitting only the flow in the direction from the upstream side vacuum sewer pipeline 2 to the downstream side vacuum sewer pipeline 3 is connected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum sewer system.

[0002]

2. Description of the Related Art Conventionally, a sewage basin with a vacuum valve for storing sewage discharged from each household, a vacuum pump station for sucking sewage, a vacuum sewer pipe connecting the sewage basin and the vacuum pump station,
Has been proposed.

In this vacuum type sewer system, sewage discharged from homes and the like is collected in a sewage basin under natural flow, and when the liquid level of the sewage basin rises, a vacuum valve is opened and sucked into a vacuum sewage pipe. It is. Then, the sewage in the vacuum sewage pipe is pushed by the expanding air, flows as a gas-liquid multiphase flow, is collected in a water collection tank in a vacuum pump station, and is then sent out to a sewage treatment plant or the like. Here, the vacuum sewage pipe is usually formed by combining a down-sloping pipe with a rising pipe called a lift.

In such a vacuum type sewer system, when there is an obstacle such as a river, a bridge, or a culvert in the middle of the vacuum sewer pipe, it is necessary to cross the obstacle. In this case, the upstream vacuum sewage pipe of the obstacle and the downstream vacuum sewage pipe are connected by a water pipe, and the upstream vacuum sewage pipe of the obstacle and the downstream vacuum sewage pipe are connected by a ventilation pipe. In addition, an obstacle traversing method using the principle of the siphon is known (for example, see Japanese Patent Application Laid-Open Nos. 6-229001 and 9-144119).

However, in the method of traversing an obstacle using the principle of the siphon, it is necessary to position the downstream vacuum sewage line lower than the upstream vacuum sewage line. Required, which has the disadvantage of increasing the overall cost. Further, this method cannot be used when the sewage collection area is lowland, the ground on the downstream side is high, and the lift loss is large.

On the other hand, as shown in FIG. 2, a water collecting tank a is installed upstream of the obstacle S, and an upstream vacuum sewage pipe c is connected to the water collecting tank a via a check valve b. With
A communication pipe e provided with an electric air release valve d is connected, and a water pipe f crossing the obstacle S is connected to the water collecting tank a and the downstream vacuum sewer pipe g. An obstacle traversing method in which a pressure equalizing pipe i provided with a pressure valve h is connected between a water collecting tank a and a downstream vacuum sewer pipe g has also been proposed.

In this obstacle traversing method, the following operation is performed.

Normally, the electric air release valve d is closed, the electric pressure equalizing valve h is open, and the downstream vacuum sewer pipe g
Reaches the water collecting tank a via the pressure equalizing pipe i, and maintains the inside of the water collecting tank a in a vacuum state. Here, the sewage from each household or the like flows in the upstream vacuum sewage pipe c as a gas-liquid multiphase flow, pushes the check valve b open, and is stored in the water collecting tank a. When a set amount of sewage is stored in the water collecting tank a, the electric equalizing valve h is closed and the electric atmospheric opening valve d is closed.
To guide the outside air to the water collecting tank a. When the pressure in the water collecting tank a reaches the atmospheric pressure, the sewage in the water collecting tank a is conveyed to the downstream vacuum sewer pipe g through the water pipe f due to the differential pressure between the atmospheric pressure and the vacuum pressure. When the sewage in the water collecting tank a is conveyed to the downstream vacuum sewer pipe g, the electric air release valve d is closed, the electric equalizing valve h is opened, and the vacuum pressure is again applied to the water collecting tank a. The sewage is guided from the upstream vacuum sewage pipe c to the collection tank a.

[0009]

In the obstacle traversing method shown in FIG. 2, since the sewage is transported by using the differential pressure between the atmospheric pressure and the vacuum pressure, when the ground on the upstream side is low, However, although the lift loss can be conveyed to the downstream side with almost zero, the electric equalizing valve h and the electric atmospheric release valve d are required, and these electric equalizing valves h
In addition, a control device for switching and controlling the electric air release valve d is required, which increases initial investment, increases man-hours and costs required for maintenance, and increases the overall cost.

The present invention has been made in view of such a problem, and has a simple structure capable of transporting sewage downstream across an obstacle without causing a lift loss with a simple structure. It provides a sewer system.

[0011]

According to the present invention, there is provided a water collecting tank disposed upstream of an obstacle and a water collecting tank disposed upstream of the obstacle and connected to the water collecting tank via a check valve. An upstream vacuum sewer pipe, a downstream vacuum sewer pipe arranged downstream of the obstacle, a water pipe connected between the water collecting tank and the downstream vacuum sewer pipe and crossing the obstacle, An equalizing pipe connected between the upstream vacuum sewer line and the downstream vacuum sewer line,
A communication pipe connected to the water collection tank, and the equalizing pipe is provided with a check valve that allows only a flow in the direction of the downstream vacuum sewage pipeline from the upstream vacuum sewage pipeline side, The communication pipe is provided with an automatic intake valve for guiding outside air to the water collecting tank when the vacuum pressure of the water collecting tank reaches a set value.

According to the present invention, the sewage flows into the water collecting tank through the downstream vacuum sewage pipe forming a gas-liquid multiphase flow. Then, the sewage stored in the water collecting tank rises in the water pipe, and the degree of vacuum of the water collecting tank decreases. When the degree of vacuum in the water collecting tank drops below a certain level, the automatic intake valve opens and guides the outside air to the water collecting tank, and the sewage in the water collecting tank is gas-liquid mixed by the differential pressure between atmospheric pressure and vacuum pressure. A stream is formed and transported from the water pipe to the downstream vacuum sewer line. When there is no sewage in the water collecting tank, the high vacuum pressure of the downstream vacuum sewer pipe acts on the water collecting tank via the water pipe, the automatic intake valve closes, and the outside air is introduced into the water collecting tank. Shut off. Since then
Similarly, when a certain amount of sewage is stored in the water collection tank, the sewage is conveyed to the downstream vacuum sewer pipe via the water pipe.

[0013] When the automatic intake valve is opened, the degree of vacuum in the downstream vacuum sewer pipe is temporarily reduced, and it tries to spread to the upstream vacuum sewer pipe through the equalizing pipe. The check valve disposed on the pressure pipe prevents a decrease in the degree of vacuum in the upstream vacuum sewer pipe.

As a result, as compared with the conventional vacuum sewage system, there is no need for expensive electric pressure equalizing valves, electric air release valves, and control devices, and the structure is simple, operated only by mechanical automatic control. Therefore, the number of man-hours and costs required for initial investment and maintenance can be reduced, and the overall cost can be reduced. In addition, pressure loss has been greatly reduced even when high lifts or multi-stage lifts are required due to obstacles such as rivers, bridges, and culverts, or because the downstream ground is higher than the upstream. Therefore, it is possible to cope with small-scale facilities, and it is possible to expand a collection area of sewage.

In the present invention, when a gas-liquid separation tank is provided in each of the upstream sewage pipe and the downstream vacuum sewage pipe, and the equalizing pipe is connected to these gas-liquid separation tanks, The sewage which forms a flow and flows through the upstream sewage pipe and the downstream sewage pipe is separated into air and sewage in the gas-liquid separation tank, so that sewage can be reliably prevented from flowing into the equalizing pipe. Also, a high vacuum pressure in the downstream vacuum sewer pipe can be guided to the upstream vacuum sewer pipe.

In the present invention, if the water collecting tank is installed in the manhole, maintenance and inspection of the automatic intake valve and the check valve can be performed in the manhole.

In the present invention, when the manhole is communicated with the outside air through the ventilation pipe, the outside air can be reliably guided to the water collecting tank when the automatic intake valve is opened.

[0018]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of a vacuum type sewer system according to the present invention.

This vacuum type sewer system is connected to a water collecting tank 1 installed upstream of an obstacle S such as a river, a bridge, a culvert, etc., and to the water collecting tank 1 installed upstream of the obstacle S. The upstream vacuum sewage pipe 2 provided, the downstream vacuum sewage pipe 3 disposed downstream of the obstacle S, and the water collection tank 1 and the downstream vacuum sewage pipe passing over the obstacle S A water pipe 4 connected between the channels 3; an equalizing pipe 5 connected across the obstacle S between the upstream vacuum sewage pipe 2 and the downstream vacuum sewage pipe 3; A check valve 7 that allows air flow only from the upstream vacuum sewer pipe 2 to the downstream vacuum sewer pipe 3 in the pressure equalizing pipe 5. In addition, the communication pipe 6 has an automatic opening and closing operation based on the vacuum pressure of the water collecting tank 1 as described later. Valves 8, for example, trade name of the applicant of manufacturing and selling "Eslon Saibakku automatic intake valves" are disposed.

The water collecting tank 1 is installed in a manhole M, and the manhole M is always in communication with the outside air through a ventilation pipe 9. In addition, a check valve 10 is provided at the end of the upstream vacuum sewage pipe 2, and a gas-liquid separation tank 21 is installed near the end. Similarly, a gas-liquid separation tank 3 is located near the beginning of the downstream vacuum sewer line 3.
1 is installed.

The pressure equalizing pipe 5 is connected between the gas-liquid separation tank 21 of the upstream vacuum sewage pipe 2 and the gas-liquid separation tank 31 of the downstream vacuum sewage pipe 3.

Next, the operation of the vacuum type sewer system constructed as described above will be described.

The downstream side of the downstream vacuum sewage pipe 3 is
It is connected to a vacuum pumping station (not shown), and the inside of the downstream vacuum sewage pipe 3 is maintained at a predetermined vacuum pressure.
Further, since the pressure equalizing pipe 5 is connected between the gas-liquid separation tank 31 of the downstream vacuum sewage pipe 3 and the gas-liquid separation tank 21 of the upstream vacuum sewage pipe 2, the upstream vacuum sewage pipe is connected. The inside of the second tube is also maintained at a predetermined vacuum pressure.

First, sewage from each household or the like forms a gas-liquid mixed-phase flow and flows through the upstream sewage pipe 2, and is separated into air and sewage in a gas-liquid separation tank 21 in front of the obstacle S. The sewage flows into the water collecting tank 1 via the check valve 10. on the other hand,
The air separated in the gas-liquid separation tank 21 flows from the equalizing pipe 5 through the check valve 7 to the gas-liquid separation tank 31 in the downstream vacuum sewage pipe 3. Therefore, sewage is prevented from flowing through the pressure equalizing pipe 5.

When sewage is stored in the water collecting tank 1, the sewage flows through the water pipe 4 to form a natural head of the sewage, and the degree of vacuum of the water collecting tank 1 is reduced. At this time, since the check valve 10 is provided at the end of the upstream vacuum sewage pipe 2,
The sewage is prevented from flowing back to the upstream vacuum sewage pipe 2 side. Further, when the degree of vacuum of the water collecting tank 1 decreases and reaches a set pressure, the automatic intake valve 8 is opened, the outside air is guided to the water collecting tank 1 through the communication pipe 6, and the water collecting tank 1 is enlarged. Pressure. As a result, due to the pressure difference between the atmospheric pressure and the vacuum pressure, the sewage in the water collecting tank 1 forms a gas-liquid multiphase flow and is conveyed to the downstream vacuum sewage pipe 3 via the water pipe 4.

When the sewage of the water pipe 4 disappears and the pressure loss head disappears, the high vacuum pressure of the downstream vacuum sewer pipe 3 reaches the automatic intake valve 8 via the water pipe 4 and the water collecting tank 1, and the automatic intake valve 8 The valve 8 closes to shut off the introduction of outside air to the water collecting tank 1. Therefore, the water collecting tank 1 is restored to a predetermined vacuum pressure.

Similarly, when the sewage flows from the upstream vacuum sewage pipe 2 into the water collecting tank 1 and is stored in a certain amount and reaches a set vacuum pressure, the automatic intake valve 8 is opened,
The sewage is conveyed to the downstream vacuum sewage pipe 3 via the water pipe 4.

When the automatic intake valve 8 is opened, the degree of vacuum in the downstream vacuum sewage pipe 3 is temporarily reduced. However, the check valve 7 provided in the pressure equalizing pipe 5 causes the check valve 7 to operate upstream. It is possible to prevent the degree of vacuum in the side vacuum sewer pipe line 2 from decreasing.

As a result, a simple structure that operates only by complete mechanical automatic control without the need for expensive electric pressure equalizing valves, electric air release valves, and control devices is required. The required man-hours and costs are small,
Overall cost can be reduced. Also, until now,
Even if high lift or multi-stage lift is required due to obstacles such as rivers, bridges, culverts, or the ground on the downstream side is higher than the upstream side, the pressure loss is greatly reduced and the scale is small. It is possible to respond with equipment, and the sewage collection area can be expanded.

In the above-described embodiment, the case where the water pipe 4 crosses the obstacle S over the obstacle is illustrated, but a water pipe that crosses the obstacle S may be used.

[0032]

As described above, according to the present invention, there is no need for expensive electric pressure equalizing valves, electric air release valves, and control devices, and a simple structure that can be operated only by mechanical automatic control. In addition, the number of man-hours and costs required for initial investment and maintenance can be reduced, and the overall cost can be reduced. Also, because of obstacles such as rivers, bridges, culverts,
Alternatively, even when a high lift or a multi-stage lift is necessary because the ground on the downstream side is higher than the upstream side, pressure loss can be greatly reduced and it can be handled with small-scale equipment, and sewage collection The area can be expanded.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a vacuum sewer system of the present invention with a part thereof omitted;

FIG. 2 is an explanatory view showing a partially omitted conventional vacuum sewer system.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 water collecting tank 2 upstream vacuum sewage pipe 21 gas-liquid separation tank 3 downstream vacuum sewage pipe 31 gas-liquid separation tank 4 water flow pipe 5 equalizing pipe 6 communication pipe 7 check valve 8 automatic intake valve 9 ventilation pipe 10 reverse Stop valve S Obstacle

Claims (4)

[Claims] 1. A water collecting tank installed upstream of an obstacle, an upstream vacuum sewage pipe arranged upstream of the obstacle and connected to the water collecting tank via a check valve, A downstream vacuum sewage pipe arranged downstream of the obstacle, a water pipe connected between the water collecting tank and the downstream vacuum sewage pipe and traversing the obstacle, an upstream vacuum sewage pipe and downstream. A pressure equalizing pipe connected between the side vacuum sewer pipes, and a communication pipe connected to the water collection tank, wherein the equalizing pipe has a flow from the upstream vacuum sewer pipe side to the downstream vacuum sewer pipe direction. A check valve that allows only outside air is provided, and the communication pipe is provided with an automatic intake valve that guides outside air to the water collection tank when the vacuum pressure of the water collection tank reaches a set value. A vacuum sewer system characterized by the following. 2. A gas-liquid separation tank is provided in each of the upstream sewage pipe and the downstream vacuum sewage pipe, and the equalizing pipe is connected to these gas-liquid separation tanks. 2. The vacuum sewer system according to 1. 3. The vacuum sewer system according to claim 1, wherein the water collecting tank is installed in a manhole. 4. The vacuum sewer system according to claim 3, wherein said manhole is communicated with outside air via a ventilation pipe.