EP0952263B1 - Unit consisting of a sewer manhole and a device for avoiding escape of odorous gases - Google Patents

Abstract

The collar (30) limits an upwardly open ring chamber (34), in which normally water (36) is collected, and which has a free overflow edge (32), via which the water reaches the sewage duct. A ring-shaped floating body (38) is provided, located in the ring chamber and can move vertically, floating normally in the water in the ring chamber. A ring-shaped, gastight apron (40) is provided, which has lower and upper edges, the lower edge being connected in a sealed manner with the floating body. An odour filter is provided (42), connected in a sealed fashion with the upper edge of the apron, closing the apron upwards like a cover.

Description

The invention relates to a manhole of a sewer with a device for preventing the escape of malodorous gases into the open.

Water is drained off via sewers, normally it is sent to a sewage treatment plant. There are sewage channels for rainwater and those for process water, often you can also find sewer channels that carry rainwater and process water. While pure service water channels can be made odor-tight, rainwater channels are necessarily open at the top so that rainwater can enter. Inlets are provided for this purpose, which are designed, for example, as street gullies. Through them, the rainwater enters the manhole and reaches the sewer.

Deposits form on the pipe walls in each sewer. A common smell emanates from these, which can escape through the manholes and the inlets. In the case of sewers, which also drain industrial water, there is also the smell of faeces, washing and rinsing water, etc. All of these malodorous gases are referred to below as channel odor.

The invention has set itself the task of avoiding that sewer smell can get outside. Especially in city centers, for example in pedestrian zones or the like, people walk near the inlets. The sewer smells rising from the sewers, which escape through the inlets, are disturbing. The canal smell is particularly intense on dry days, when people like to populate streets.

Devices are known from the prior art which make it possible to prevent channel odor from escaping through the inlets to the outside by means of a siphon, see for example publication EP-A-0 675 238. For sanitary purposes Systems are known as so-called odor traps, in which the process water closes the line by suitable guidance in the area of the odor trap. Part of the drained water always remains in the odor trap. Such odor traps are not suitable for shutting off a manhole. There must be the possibility that gas can always penetrate through the manholes and the inlets or outwards. However, it should be avoided that these gases are odor-laden. A closure such as that which is provided with the odor traps described would also have safety-related problems, since a gas pressure could accumulate in the sewer which could have dangerous effects. Even a normal walk through the sewer could become a safety risk. Such pressure or the accumulation of harmful gases could only be relieved by pushing the water trapped in odor traps outwards. However, this could in turn lead to large amounts of dirt.

The aim of the invention is therefore to provide a device of the type mentioned that constantly allows free entry and exit of gases from the manhole to the outside, but removes the channel odor from these gases and which also allows ring water to be unhindered by the inlet can get down into the manhole.

The object of the invention is to achieve this goal, which has not yet been formulated. The object is achieved by a device in a sewer shaft of a sewer to prevent the escape of malodorous gases into the open, the sewer shaft having an inlet, for example a street gully, and below this inlet an essentially vertical shaft wall and the following further features are provided: a) a collar protrudes from the shaft wall inwards and upwards, which delimits an annular space which is open at the top and in which water normally collects and which has a free edge which forms an overflow edge, through which water reaches the sewer, b ) an annular floating body is provided which is located in the annular space, can move vertically and which normally floats in the water of the annular space, but lies as close as possible to a wall of the annular space when the annular space has dried out, c) an annular, gas-tight apron is provided that have a lower and an upper edge has, the lower edge being connected to the floating body in a sealed manner and d) an odor filter is provided which is connected to the upper edge of the apron in a sealed manner and closes off the apron like a lid.

For a better understanding of the invention, the way that gases can take from the sewer into the open is first described. For the gases, the path through the filter to the outside is clear. The gases can flow through the filter as freely as possible, it is designed accordingly. However, the odor is filtered out of the gases, i.e. removed. As a result, gases can both enter the sewer from the outside and, conversely, gases can escape from the manhole. A pressure difference between the manhole and the outside world cannot build up in this way. Access to sewers is not affected or changed by the device according to the invention.

The odor filter may or may not be permeable to water. It is normally not permeable to water. It is preferably protected at the top by a shield so that it cannot be wetted by water or covered or blocked by solids that are carried with the water. It is preferably designed to be exchangeable, so that an exhausted odor filter can be exchanged at certain time intervals. For example, the odor filter is designed as an activated carbon filter.

However, water must be able to get into the sewer from top to bottom. According to the invention, this is made possible by the fact that water reaching through the inlet into the sewer shaft can collect in the annular space and from there via the overflow edge can get further down into the sewer. Some water always remains in the annulus. It forms a seal against the ring-shaped floating body. In this way, sewer smell cannot pass between the collar and the floating body and in this way can escape outdoors. If the water supply in the annular space has dried up due to a time without rain, the floating body rests against a suitably designed wall of the collar and forms an odor-tight barrier. Even if this is not as good as sealing over water, a considerable reduction in odor is achieved, especially since gas can pass through the odor filter essentially unhindered, so this flow path is preferred by the gas.

In an advantageous development, the apron is essentially designed so that it has the shape of a cylinder jacket. Together with the odor filter, which is preferably designed essentially as a flat disc, it forms a hat that is open at the bottom. The float is at the bottom of this hat. These parts are preferably interchangeable so that they can be removed upwards through the open inlet. This simplifies it Assembly and maintenance.

There are two different constructions for the design of the device. They differ essentially on the one hand in whether the apron is rigid or movable or flexible in the vertical direction, and on the other hand in whether the odor filter should and can take part in the movement of the swimming ring or not. In the first version, the apron is rigid, it carries the odor filter, which in this way requires no further attachment. However, it is advantageous in this embodiment to guide the odor filter in some way so that it always assumes a position that is as horizontal as possible. This also ensures that the float is always essentially horizontal.

In the other embodiment, which is advantageous, the apron is movable or elastic in the vertical direction. It is, for example, as a bellows, e.g. a rubber bellows. Their elasticity and their possibilities of movement in the vertical direction are dimensioned such that the floating body can move freely between its lowest position and its highest position within the annulus. The odor filter is free from the movements of the float, it is held by a simple supporting part that protrudes from the shaft wall or the like. It is designed in such a way that it practically does not hinder the water falling down. In this version, the floating body does not have to bear the weight of the odor filter. The floating body can therefore be made much simpler and in particular much smaller than in the first embodiment.

FIG. 1:

ein Axialschnitt durch einen Kanalschacht mit Einlauf, Sandfang und der erfindungsgemäßen Vorrichtung sowie durch einen hier nur angedeuteten Abwasserkanal, die Schürze ist starr ausgeführt,

FIG. 2:

eine Darstellung entsprechend Figur 1 für eine Ausführungsform, bei der die Schürze als Balg ausgebildet ist, gezeigt ist der Normalzustand mit schwimmendem Schwimmkörper, wie in Figur 1,

FIG. 3:

eine Darstellung entsprechend Figur 2, jedoch mit ausgetrocknetem Ringraum und

FIG. 4:

eine Darstellung entsprechend Figur 2, jedoch nun mit Wasserzulauf von oben, zu erkennen ist das Überströmen über einen Überströmrand.

Further advantages and features of the invention emerge from the remaining claims and the following description of non-restrictive exemplary embodiments which are explained in more detail with reference to the drawing. In this show:

FIG. 1:

3 shows an axial section through a sewer shaft with inlet, sand trap and the device according to the invention and through a sewage sewer only indicated here, the apron is of rigid construction,

FIG. 2:

a representation corresponding to Figure 1 for an embodiment in which the apron is designed as a bellows, the normal state is shown with a floating float, as in Figure 1,

FIG. 3:

a representation corresponding to Figure 2, but with a dried-out annulus and

FIG. 4:

a representation corresponding to Figure 2, but now with water supply from above, the overflow over an overflow edge can be seen.

All figures show a substantially vertical, cylindrical duct shaft 20 which is delimited by an inner wall 22. For the invention, the duct shaft does not necessarily have to run completely vertically, it is sufficient that a short section runs vertically or essentially vertically.

The sewer shaft is closed at the top in a street level 24 by an inlet 26, which is designed here as a manhole cover, also called a gully. There is a sand trap 28 directly below the inlet 26, it is already provided according to the prior art, it is to prevent leaves, dirt particles and the like from falling down. A sand trap is of great advantage for the present invention because it results in essentially only water flowing further down. In combination with the invention, a sand trap 28, as is already provided in most sewer ducts, is therefore of great advantage.

The odor barrier according to the invention is therefore preferably always below the sand trap 28. It has a collar 30 which projects essentially inwards and upwards from the inner wall 22. It is tightly connected to the inner wall 22 and made of a material, for example plastic or cast iron, which is both water and gas tight. In the exemplary embodiment according to FIG. 1, this collar 30 consists of an initially essentially horizontally extending section and a conically extending section, at the free end of which there is an upper current edge 32. All water flows down over this edge.

The collar 30 described in this way delimits an upwardly open annular space 34, which in the exemplary embodiment shown is additionally defined by a section of the inner wall of the sewer shaft. Water 36 accumulates in it. Furthermore, in this annular space 34 there is an annular floating body 38, which is designed like a lifebuoy. For example, it is made of polystyrene and has a dense outer skin. In the exemplary embodiment shown, it has a slightly conical part which interacts with the conical region of the collar 30. This has the advantage that when the annular space 34 dries out, a seal is formed between the collar 30 and the floating body 38.

The floating body 38 is dimensioned such that it has sufficient buoyancy for all parts, with which it is rigidly connected. This will be discussed in the following.

The floating body 38 is connected to a gastight apron 40. It is essentially designed as a cylinder jacket. It has a lower edge which is connected to the floating body 38 and an upper edge which is tightly connected to an odor filter 42. This is essentially designed as a flat, cylindrical disc. It closes the apron 40 at the top like a lid.

The buoyancy of the float 38 is now selected so that it can carry the weight of the odor filter 42 and the apron 40, but also its own weight, when the annular space 34 is filled with water, without being pressed onto the collar 30, that is to say it remains in a floating state.

in the exemplary embodiment according to FIG. 1, a guide 44 is additionally provided. It has the effect that the unit comprising the float 38, the apron 40 and the odor filter 42 can essentially only move in the vertical direction, that is to say in the direction of the double arrow 46. The guide 44 shown here is only one example of a possible training. It consists of three star-shaped, essentially L-shaped support parts which protrude from the collar 30 and then run towards the center. It supports a central part 48, on which the odor filter 42 can move up and down.

The embodiment according to FIGS. 2 to 4 differs from the previously discussed embodiment according to FIG. 1 in that the apron 40 is now designed to be movable or elastic in the vertical direction, which makes it possible to arrange the odor filter 42 in a stationary manner. The weight of the odor filter 42 then no longer has to be borne by the floating body 38. Otherwise, the basic training is unchanged.

FIG. 2 shows the annular space 34, which is at least partially filled with water 36 and in which the floating body 38 is in the floating state. The apron 40 is designed as a rubber bellows. The odor filter 42 is carried by a supporting part, which in turn is supported on the collar 30 or a corresponding holding part. This supporting part is designed in such a way that the odor filter 42 can be easily replaced, for example it is only removed upwards, so it lies tightly due to its own weight.

In the illustration according to FIG. 2, the floating body 38 floats within the annular space 34, which is no longer completely filled with water 36. As in the embodiment according to FIG.

In the illustration according to FIG. 3, the water 36 in the annular space 34 has evaporated to such an extent that the floating body 38 no longer swims sufficiently; its conical surface now lies against the conical surface of the collar 30. At this point, additional rubber lips or other rubber seals can be used to improve the seal.

Finally, FIG. 4 shows the state that water 36 flows continuously from above, the annular space 34 is completely filled with water 36, which flows down over the overflow edge 32.

So with a waterproof protective shield is designated, which covers the odor filter 42 above, see e.g. Figure 2.

Claims (8)

1. A unit comprised of a sewer manhole (20) and of a device located within said manhole and intended to prevent malodorous gases from escaping into the air, said manhole (20) having an inlet (26) such as a road gully and beneath said inlet (26) a substantially vertically oriented manhole wall, the following characteristics being further provided:

   a) from the manhole wall, a collar (30) sealedly protrudes inward and upward and defines an open annular volume (34) that is open toward the top and which, in use, normally collects water (36) and has a free edge forming an overflow edge (32) over which water (36) is allowed to enter the sewer,

   b) there is provided an annular, gas tight apron (40) having a lower and an upper border,
   characterized in that the following features are further provided:

   c) there is provided an annular float (38) that is located in the annular volume (34), is capable of moving vertically and which, in operation, normally floats in the water (36) of the annular volume (34) and, when the annular volume (34) is dried out, fits as tightly as possible on a wall of the annular volume (34), the lower border of the apron (40) being sealedly connected to the float (38) and

   d) there is provided an odor filter (42) that is sealedly connected to the upper border of the apron (40) and closes said apron (40) toward the top in a cover-like fashion.
2. The unit according to claim 1, characterized in that the apron (40) is substantially shaped like a cylinder jacket.
3. The unit according to claim 1, characterized in that the odor filter (42) is substantially shaped like a circular disk.
4. The unit according to claim 1, characterized in that the apron (40) is configured to be rigid and that the odor filter (42) is carried by the apron (40) and, as a result thereof, by the float (38).
5. The unit according to claim 1, characterized in that the apron (40) is configured to be movable or elastic in a vertical direction, more specifically that it is implemented as a bellows, and that the odor filter (42) is connected to the manhole wall or the collar (30) through a carrier member past which water (36) is allowed to flow along the side thereof.
6. The unit according to claim 1, characterized in that the collar (30) has an inner wall (22) that extends along an envelope of cone.
7. The unit according to claim 1, characterized in that there is a dirt collecting area that is provided at the deepest location within the annular volume (34).
8. The unit according to claim 1, characterized in that the float (38) is substantially configured like a life belt.