HRP20020293A2 - Method and device for periodic rinsing of a waste water pipe - Google Patents

Description

The invention relates to a process for flushing waste water pipelines using compressed air, in which some amount of water, which is collected in an accumulation tank connected to the pipeline, is led into the pipeline.

The invention further relates to a device for flushing waste water pipelines, in which a certain amount of water is led through the pipeline using compressed air, with a compressor and a pressure boiler connected to it, which is connected to the pipeline via a valve, and with an accumulation tank for collecting the amount of water , which is supplied via the water supply.

The orderly removal and cleaning of waste water, which accumulates in households and plants, is gaining more and more importance. At the same time, above all in the rural area, there is still a need to make up for the lag, where compared to urban structures, the expenditure for the construction of canals is high, as a result of the required long lengths and relatively small connection values. In addition, unfavorable construction technical conditions often appear, such as hilly terrain, which requires large laying depths and pumping stations. For reasons of economy (merging several settlements, that is, disposal areas) as well as water protection (dilution of purified wastewater contaminated with residues), purification devices are usually located near the recipients; this also often requires very long connecting lines between the last household connection and the treatment device in question.

Wastewater drainage must be carried out in such a way that control and maintenance work is possible (visual monitoring, flushing, etc.). For this purpose, the lines should normally be laid flat. Control shafts must be located at the breaks (in case of horizontal or vertical changes of direction). As a rule, these control shafts are located at intervals of 10 m to 150 m, depending on the shape of the terrain in question. These control shafts make the construction of waste water lines even more expensive and, in addition, they are a nuisance in the area of agriculturally useful surfaces. Due to the rectilinear laying of waste water lines, between the manholes there are also often extraordinarily large laying depths, up to several meters deep, in exchange for which a depth of approx. 1.30 m would be sufficient in relation to the necessary safety against freezing. After all, control shafts and connecting elements represent weak points with regard to the risk of leaks, various settlements, etc.

In order to properly flush the channel, in order to prevent sedimentation and "growths", an attempt has already been made to envisage a waste water channel, which follows the profile of the terrain, which therefore also has the lowest places at the lowest points of the terrain, instead of an expensive classic waste water channel with control shafts etc. in the water route, in which waste water is present in operation in the manner of a siphon. These collected amounts of water are periodically pushed by blows of compressed air through the waste water line, which is brought to the waste water line, in order to wash away possible deposits in the water. Wastewater drainage here is expediently carried out as a welded pressure line, which is installed at the laying depth, which is sufficient only for safety against freezing, in which case control shafts are not required. In normal operation, waste water flows without pressure through the pipe, since the pipe quite understandably, both when it is laid uphill and downhill, lies with its tops below the pressure line.

In this way, the costs for the waste water line can be reduced to half the costs, which are required for conventional waste water drains with straight lines, or can even be reduced below that. In view of the large lengths, as a rule, required in rural areas, the additional costs for the compressed air station are no longer important.

It turned out, however, that with such a method, the amounts of water collected at the lowest points are often too small and not sufficient for the desired flushing effect, where, first of all, problems are caused by deposits in the water outside these lowest points. In addition, it must be mentioned that in the case of pipeline routes, where there are no such places with the lowest point with water collection, because the terrain only falls and/or is flat, and also on sections of water above the highest point with the lowest point on the pipeline route, such is not possible flushing with "water plugs" using compressed air.

From US 4 391 288 A, which is considered the starting point for this invention, it is known that by means of a mammoth pump, the waste water liquid is carried at a higher speed through the siphon of the outflow water. At the same time, compressed air is fed into the mammoth pump, in order to produce a water-air mixture, which results in an increased pressure drop, so that the waste water, which is collected in the tank, can flow through the tank at a slightly higher speed than normal. chiffon. In doing so, however, only slight pressure differences can be achieved, and thus only slightly increased flow velocities, so that the purification effect cannot be reliably achieved. First of all, with stronger deposits in the siphon, it is not possible to remove these deposits, and therefore there is still a risk of clogging. In addition, the installation of a mammoth pump requires a relatively high construction cost.

Therefore, the task of the invention is to ensure reliable flushing of waste water lines using water plugs with the use of compressed air in arbitrary routes, in order to prevent sedimentation and growth of lines.

The method in accordance with the invention of the type mentioned in the introduction is therefore indicated by the fact that the storage tank, which is designed to be sufficiently resistant to pressure, and which is connected to the pipeline in the manner of a connected container, is periodically exposed to a blow with compressed air, while the inflow of water into the storage tank closes, so that the amount of water is pushed from the storage tank into the pipeline by means of compressed air.

The device according to the invention of the type mentioned in the introduction is appropriately indicated by the fact that the pressure boiler is connected to the pipeline via a sufficiently pressure-resistant storage tank, with a valve interface between the pressure boiler and the storage tank, where the water inflow into the storage tank is placed a closing device, eg a latch.

The measures according to the invention conveniently correspond to the previously set goal. The storage tank has a sufficient volume of water for the desired flushing purposes, e.g. 2 m3 (2000 l), already according to the section of the waste water pipeline, so that a sufficiently large water plug would be pushed through the waste water pipeline at the required speed when compressed air hits it. The air pressure is already determined according to the length of the pipeline, where as a rule an overpressure of 1 or 2 bar is sufficient. Correspondingly, the storage tank should be made resistant to pressure, of course to the inflow and outflow of a closed storage tank, for which there are a wide variety of, in themselves, common types of designs. The pressure vessel can, for example, be made of concrete, metal or synthetic material, especially fiber-reinforced synthetic material. In normal operation, waste water flows through the pipeline in free fall. For flushing, primarily once a week, the storage tank is subjected to a blast of compressed air from a pressure boiler, which closes off the inflow into the storage tank, so that the development of pressure, i.e. the transport of the water plug, will only follow in the desired direction through the waste water pipeline. For the pressure shock of the storage tank, the valve is opened, which is located in the connection between the storage tank and the pressure boiler.

The storage tank itself could be a separate tank, supplied with water, which is placed parallel to the waste water drain and can be connected to it if necessary (when flushing), in which case the waste water pipeline would have to be closed above the connection of the storage tank on waste water pipeline. However, an accumulation tank integrated in the waste water system is suitable, that means, the waste water flows from the accumulation channel, pre-tank, etc., coming via the inflow, that means through the supply water, through the accumulation tank and from here on into the waste water pressure line, and that in normal operation. Thus, the waste water itself, which is collected in the storage tank, is used for flushing purposes. In this case, it is expedient to simply assume that the storage tank is connected to the inlet end of the pipeline as a siphon. However, one version would be conceivable, in which the storage tank does not collect waste water in normal operation, but the waste water simply flows through the tank, where a shut-off valve is provided at the outlet of the storage tank, which can be closed in case of flushing, in order to after closing this shut-off valve, the desired amount of water could collect in the storage tank. After reaching the required level in the storage tank, which can for example be determined using a level sensor, the shut-off valve at the outlet of the storage tank is opened, after the closing device is closed in the supply to the storage tank, which is followed by the opening of the shut-off valve synchronously with the opening compressed air valve in the connection between the storage tank and the pressure boiler.

In the event that a certain amount of water is collected in the storage tank and that it contains it, for a simple connection to the waste water pipeline it is expedient, when the waste water pipeline is connected to the storage tank via the water element, which is connected to it in the area of the bottom of the storage tank and from this it rises to a level slightly below the upper side of the storage tank.

The volume of the storage tank can be dimensioned in such a way that when the pipeline is flushed, there are several successive flushing blows, which follow with the appropriate amount of water, and in this case the storage tank is repeatedly exposed to the blow of compressed air.

This command can also be triggered automatically, as in the case of a simple flush water impact, by means of an electronic control unit, which is equipped with a time measuring unit (clock), and which is connected to at least a shut-off device in the water supply to the storage tank for automatic control. and the valve between the pressure boiler and the storage tank. In order for the compressor to be able to produce the required pressure in the pressure boiler if necessary, the control unit can also be attached to the compressor, in order to automatically cause the pressure to rise just before the flushing stroke, before issuing a command to the shut-off device and valve.

In the case of flushing, the water plug is pushed by pressure from the pressure boiler into the waste water pipeline, where it flows through it at a suitable speed, for example 6 or 7 m/s.

The invention, with reference to the drawing, is further explained below on the basis of suitable exemplary embodiments, which, however, should not be limited to.

This is shown by:

Figure 1 schematic longitudinal section through the waste water pipeline in the field, with the flushing station located at the upper end;

Fig. 2 the pipeline flushing station according to Fig. 1, compared to the one above, on an enlarged scale; and

Figures 3, 4 and 5 show this washing station schematically in different stages of operation, namely during normal operation (Figure 3), during the rinsing operation (Figure 4), as well as at the end of the rinsing operation (Figure 5).

Figure 1 shows the waste water pipeline (pressure line) 1, which only follows the schematically drawn characteristics of the terrain 2, where the location of the lowest point 3 is shown as an example, with one type of waste water siphon in the pipeline 1, which results in " water plug". As it turned out, such water plugs are mostly not enough to flush the waste water pipeline 1, to prevent the deposition of solids and growth in the water. In addition, it is conceivable that solids settle in the pipeline and above such places of the lowest point 3, so that flushing is required there as well. The same applies to siphons in pipeline 1, which for example pass under an obstacle, such as a river bed.

Accordingly, at the upper end of the pipeline 1, a flushing station 4 is provided, through which waste water is fed into the waste water pipeline 1 via the supply line 5, coming, for example, from the accumulation channel or pre-tank.

At the lower end of the waste water pipeline 1, for example, a shaft 6 is provided for discharge into the gravity channel 7.

Regular pressure cleaning, e.g. once a week, carried out using the rinsing station 4, as will be explained in more detail later on the basis of Figure 2, it is possible to remove the deposits that form in the water 1, and that at the lowest points 3 no disturbing sediments remain.

According to Figure 2, the washing station 4 is designed with an accumulation tank 8, which can be pressurized by a pressure boiler 9, especially by a compressed air tank, through a pressure line 10, in which a valve 11 is located. The compressor 12 is used to obtain pressure, which is connected to the pressure boiler 9.

The storage tank 8 is connected to the feed 5 via a latch device 13, primarily in the form of a latch. The storage tank 8 is connected to the waste water pipeline 1, which is located at the upper end at a height just below the upper side of the storage tank 8. type of siphon or connected vessel, as indicated by the water level at 15 in Figure 2.

In normal operation, the waste water coming from the supply line 5, with the valve device 13 open, flows into the storage tank 8, where a predetermined amount of waste water is collected, approximately with a volume of 2000 l, and then the waste water flows through the water element 14 into the pipeline waste water 1, designed as a pressure line. The valve 11 in the connection line 10 for the pressure boiler 9 is closed during this normal operation. To flush the pressure line 1, the shut-off device 13 is closed, and the valve 11 is opened, so that the water plug, located in the storage tank 8 (as well as in the water element 14), is exposed to a pressure shock, for example of the order of 1 or 2 bar. With this, this water plug, which is marked 16 in Figure 2 and also in Figures 3 and 4, is pushed through the waste water pipeline 1 by impact, whereby it flows through this pipeline 1 at a speed of the order of at least 6 to 7 m/s. . This water plug 16 washes deposits and sediments into the water 1, so that the gradual increase of the water 1 due to the deposition of solid substances on the walls of the water is avoided.

Depending on the condition, such flushing can be carried out, for example, once a week, if necessary, however, more often, in the case of heavily polluted wastewater.

In order to carry out washing in an automatic way, an electronic control unit, schematically presented in Figure 2, marked 17, is provided, which is connected to a time measuring device or clock 18, which is controlled by time, for example, it is activated once a week at a certain time. and at the same time, the shut-off device 13 closes, and the valve 11 opens, after the compressor 12 has previously been on for a long enough time, and the pressure in the pressure boiler 9 would be raised for flushing. The corresponding control lines for the shut-off device 13, for the valve 11 and for compressor 12 are shown in Figure 2 with 19, 20, and 21, respectively.

The control unit 17 can be designed in such a way that the storage tank 8 is repeatedly exposed to a pressure shock by repeatedly opening and closing the valve 11, so that several water plugs are pushed one after the other through the line 1. For this purpose, the storage tank 8 can be designed with a correspondingly large volume, and only a part of the volume is pushed through line 1; but it is also conceivable that, between individual water impacts, waste water is collected again in the storage tank 8; this will first of all be expedient when a sufficiently strong inflow of waste water is ensured. If necessary, the collection of appropriate amounts of water can also be monitored using level measurement sensors, which are not shown in detail in Figure 2, and whose output signals are fed to the control unit 17.

Figure 3 schematically shows the normal operation of the flushing station 4. At the same time, the valve 11 is closed, the shut-off valve 13 is, on the contrary, open, and the waste water coming from the inlet 5 flows freely through the device, which creates the aforementioned water plug 16 in the storage tank 8 , as well as in the water element 14.

Figure 4 shows the state during the flushing operation, in which the shut-off device 13 is previously closed and the valve 11 is open. The air pressurized by the compressor 12 in the pressure tank 9 pressurizes the water plug 16 and pushes it through the line 1. During this time, the waste water can be collected in the inlet above the closed shut-off device 13, which ensures the corresponding accumulated volume 22 in bring 5.

Figure 5 shows the completion of the flushing action, where the water plug (16 in Figures 3 and 4) has left the flushing station 4 and been pushed into line 1. This condition can also be determined, if desired, by means of sensor 23, which is located on at the bottom of the storage tank 8, and which is connected to the control unit 17 (see Figure 2) via the output line 24, in order to notify it when the storage tank 8 is empty. The control unit 17 then gives the valve 11 a closing command, as well as the closing device 13 an opening command, so that the waste water from the inlet 5 can again flow into the storage tank 8. This again results in normal operation, which is shown in Figure 3, because the water the plug 16 first forms in the storage tank 8, as well as in the water element 14, after which the waste water again flows freely into the water line 1.

Claims (14)

1. The procedure for flushing with compressed air, the waste water pipeline (1) in the fall, which follows the characteristics of the terrain (2), which has at least one place with the lowest point (3), where some amount of water, which collects in the accumulation the tank (8), which is connected to the pipeline, leads to the pipeline, indicated by the fact that the collected amount of water is kept in readiness in the storage tank (8), made sufficiently resistant to pressure, shaped like a siphon, which is connected in the manner of a connected vessel with the pipeline falling (1) and during the time that the water supply (5) to the storage tank is closed, it is periodically exposed to a blow of compressed air in order to push the prepared amount of water at least partially using compressed air by hitting it from the siphon storage tank (8) into the pipeline (1). 2. The procedure according to claim 1, indicated by the fact that compressed air is fed into the storage tank (8) under a pressure of approx. 2 bar. 3. The method according to claim 1 or 2, characterized by the fact that the storage tank (8) for giving multiple successive blows for rinsing is subjected to a blow of compressed air several times in a row. 4. The method according to one of claims 1 to 3, characterized in that the amount of water from the storage tank (8) is pushed through the pipeline (1) at a speed of about 6 m/s. 5. The method according to one of claims 1 to 4, characterized in that the amount of water is pushed from the storage tank (8) into the pipeline (1) approximately once a week. 6. The waste water pipeline (1) in the fall, which follows the characteristics of the terrain, which has at least one place with the lowest point (3), with a device for flushing the pipeline (1) using water, which can be guided through the pipeline under the impact of compressed air, with the compressor (12) and the pressure boiler (9) connected to it, which is connected via the valve (11) to the pipeline (1) and to the storage tank (8) for collecting the amount of water, as well as to the water supply (5), where water can be fed into the storage tank (8) through the water inlet (5), indicated by the fact that the storage tank (8) is shaped like a siphon and is connected to the pipeline (1) in the manner of a connected vessel, and that the pressure boiler (9) is connected with the pipeline (1) through the storage tank (8), made sufficiently resistant to pressure, with the intermediate connection of the valve (11) between the pressure boiler (9) and the storage tank (8), where in the water supply (5) to the storage tank ( 8) located locking device (13), for example one latch. 7. Falling pipeline according to claim 6, characterized in that the storage tank (8) is a pressure tank, designed for pressures of at least 2 bar. 8. Falling pipeline according to claim 6 or 7, characterized in that the storage tank (8) is a concrete pressure tank. 9. Falling pipeline according to claim 6 or 7, characterized in that the storage tank (8) is a pressure tank made of fiber-reinforced synthetic material. 10. Falling pipeline according to claim 6 or 7, characterized in that the storage tank (8) is a metal pressure tank. 11. Falling pipeline according to one of claims 6 to 10, characterized by the fact that in the working position the pipeline (1) is connected to the storage tank (8) via the pipe element (14), which in the area of the bottom of the storage tank (8) is connects it and raises it to a level slightly below the upper side of the storage tank (8). 12. Falling pipeline according to one of claims 6 to 11, characterized in that the storage tank (8) has a volume of 2 m3. 13. Pipeline falling according to one of claims 6 to 12, characterized in that the shut-off device (13) in the water supply (5) towards the storage tank (8) and the valve (11) between the pressure boiler (9) and the storage tank ( 8), associated electronic control unit (17) for automatic control, which is equipped with a clock (18). 14. Falling pipeline according to claim 13, characterized in that the control unit (17) can give commands to the compressor (12) to automatically activate the pressure increase in the pressure boiler (9) before starting the shut-off device (13) and the valve (11).