GB2306343A - Device for separating sand and stones from sewage water. - Google Patents

Description

c 2306343 DEVICE FOR CONTINUOUSLY SEPARATING SAND AND STONES The

subject-matter of the present invention is a device for the continuous separating of sand and stones out of a pipeline.

Sewage pipes, with which especially surface water from streets and areas led into a sewage treatment plant, constantly carry along sand and fine stones which have to separated out before the sewage pipe enters the waste water plant. In order to separate out these bodies, which have a greater density than the specific density of water, sedimentation basins are used which are connected to the sewage plant, upstream thereof. In the sedimentation basins, through widening of the cross-section, the rate of flow of inflowing water, which carries solid bodies with it, can be reduced to substantially zero and the solid bodies can then settle, before there is another increase in the rate of flow with which the pipe takes the water to the waste water plant. A method is also known for leading sandladen water tangentially into a circular separating basin and separating out the heavy solids contained therein through centrifugal forces and by their own weight.

Settling basins have to be designed to be very large in relation to the cross-section of the sewer, in order to have the desired separating efficiency. The centrifugal separating basins cannot be designed 2 significantly smaller and with both known devices, cleaning of the separator is only possible when the influx of water is halted.

The object of the present invention is to provide a device for the continuous separating out of sand and stones from a pipeline, which device, besides having an excellent degree of separation, does not necessitate any intermediate banking-up of the water to calm the water which is to be cleaned.

According to the present invention there is provided a device for the continuous separating of sand and stones out of a pipeline, said device being located in a collecting chamber between an inflow and an outflow of said pipeline, characterised in that the inflow and the outflow are connected to one another by a pipeline section serving as a separator, the pipeline section having, on the inflow side, a first portion running downwards to the horizontal and, on the outflow side, a second portion running upwards, an opening being provided at the common lowest part of such portions.

Surprisingly, it has been discovered that it is 2,5 possible to successfully separate out the grains of sand and stones carried along, by fitting in the pipe, at its deepest point, a section which runs first downwards and then upwards. Through the initial slight downward gradient and the steep rise which 3 C-111 follows it, the solid bodies which have a higher density than the water are no longer carried upwards and fall down out of the pipeline into a collecting basin. The pipeline can be V-shaped in longitudinal section or have a by-pass which is designed as V-shaped and which is connected at the base with the pipeline in two places. The section in which the separation takes place can be laid into U-shaped holding devices correspondingly arranged on the container wall, and can, if necessary, be removed from the cleaning is necessary. Cleaning can, take place without the separating removed, since the latter traverses preferably diagonally, and at the side there is sufficient space to introduce into the sump of the container.

extending over the whole length of theseparating pipeline, a perforated plate container to catch the solids can simply be arranged immediately below the separating aperture, at the deepest point. Separating out sand and stones can be done without any reduction in the f low speed of the water to be cleaned and without hydraulic loss of height.

container when however, also section being the container of the pipeline a suction pipe Instead of a container The separating pipeline can be manufactured from sheet metal, cast-iron or plastics as a self-contained part, and can be inserted into a container of any crosssection.

C) 4 The present invention will be further illustrated, by way of example, with reference to the accompanying drawings, in which:

Figure 1 is the line I-I Figure 2 is II in Figure Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 cross-section through a container along in Figure 2, longitudinal section along the line II- a 1 ' plan view of the device, side view of the separating pipeline, plan view of the separating pipeline, a i S i S i S is longitudinal section through a further development of the device, is a plan view of the device of Figure 6, is an enlarged view of the by-pass and is a cross-section through the by-pass, along the line IX-IX in Figure 8.

As illustrated in Figures 1 and 2, the device 1 is inserted in a container 3 between the inflow 5 and the outflow 7 of a sewer pipe 9. The device 1 can be carried on two U-shaped supports 11, supporting the inflow 5 or the outflow 7 from below. The supports 11 can be attached to the wall of the container 3 by fastening means. The level of the inflow 5 and that of the outflow 7 lie essentially at the same height; the outflow 7 lies only round the normal fall in the sewer 9, below the inflow 5. The cross-section of the section of the pipeline 13 connecting the two openings 0 (inflow 5 and outflow 7) corresponds substantially to that of the sewer 9. Below the pipeline section 13, a by-pass 15, running in a V-shape, is arranged with a first portion 17 inclined downwards and a second portion 19 running upwards. The slope of the first portion 17 is smaller than the slope of the second portion 19.

An opening 23 is provided in the region 21 of the two portions 17 and 19 and is directed downwards. A tubular or U-shaped connection piece 25 can also be provided at the opening. The V-shaped by-pass 15 begins preferably directly at the inflow 5 and ends flows again into the pipe section 13 in the region 15 the outflow 7.

or of On the side, turned away from the inflow 5, of the access to portion 17, there can be attached to this section a deflector 27 which projects into the cross- section of the pipe section 13.

The base of the shaft 3 can be narrowed in the shape of a truncated cone, in order to simplify the extraction of deposited sand and small stones 29 by means of a suction pipe.

The pipeline section 13 can be designed as a closed tube or, as may be seen from Figure 1, as a channel which is open upwards and can be closed on the top by a cover 31.

6 The device 1 works as follows: waste water carrying sand and stones flows in the direction of arrows A through the sewer 9 from the left side in Figure 2, through the inflow 5 into the device 1. If the influx of water is small - such a case is shown in Figure 2 the total amount of water and solid matter flows through the by-pass 15. In this process, the container 3 first of all fills with water, the water rising in each case to the influx level in container 3. Once the container 3 is filled to this extent with water, the water continuing to flow in rises through the second section 19 and reaches the sewer 9 again through the outflow 7. The sand and stone solids 29, carried along and having a higher specific density than water, fall downwards through the opening 23 out of the by-pass 15 into the container 3. If the amount of inflowing water is greater, the portion falling over the level of the upper edge of the deflector 27 can flow directly through the pipeline section 13 to the outflow 7.

Since, as is well known, grains of sand and small stones carried along roll or are pushed on the base of the sewer 9, they do not get beyond the deflector 27 but slip through portion 17 towards the opening 23, from where they fall into the container 3. The water carrying them, freed of solid bodies, rises again upwards through the steep portion 19 into the pipe section 13 and leaves the container 3 through the outflow 7. Should the by-pass 15 be blocked by too big a stone or shingle, no back pressure can arise in the 0 7 sewer 9 since then all the water - including all the contaminants of course - can flow directly through the pipeline section 13. If any contamination is noticed, the by-pass 15 or the two portions 17 and 19 can be cleaned from above in simple fashion by raising the cover 31.

Cleaning the container 3 of the solid matter 29 collected therein can be done in a simple way by sucking out from above, the suction pipeline of a cleansing vehicle being lowered into the container 3 beside the device 1. There is no need for the influx of water to be interrupted during this process.

In a further development of.the invention, instead of a by-pass 15, the pipe section 13 can b;e formed as a trough 33 which is V-shaped in longitudinal section, as shown in cross-section in Figure 4. By means of a deflector, or a plurality of deflectors 27, running at right angles to the direction of flow, grains of sand and stones can be prevented from getting directly from inflow 5 to outflow 7.

In the development of the invention according to Figures 6 to 9, the device 101 is inserted in a frame 102, the crosssection of which corresponds to the cross-section of the container 103 and which is placed on the upper edge of the lower portion of the container 103. The diameter D1 of the inflow 105 i.s greater than 8 n the diameter D2 of the outflow 107. The two pipes (inflow 105 and outflow 107) lie diagonally opposite one another, the lower end points S of both these parts lying at the same height.

The frame 102 carries a first portion 117, inclined downwards, which has the form of a channel and extends over at least three-quarters of the container crosssection. To the lowest point of the first portion 117 is joined a second portion 119 which connects the first portion 117 with the outflow 107. The two portions 117 and 119 form the pipeline section 113 connecting the inflow 105 with the outflow 107.

The water entering the container 103 is led exclusively into portion 117 and sand or small stones 129, which have been carried along, fall into the first portion 117 and, at the lower end of same, down through the opening 123. The water, freed of small stones and sand 129, is diverted at the second portion 119, rises upwards and can leave the container 103 through the outflow 107.

The differing diameters of the inflow 105 and the outflow 107 cause differing flow speeds vl,v2. The greater diameter D1 of the inflow 105 causes a smaller speed vl, at which the water and the dirt load are led in, than the speed v2 in the outflow 107, which only carries away water without any dirt.

0 9 A shutter 110 can be placed in front of the outflow aperture 108. If there should be overdammed backwater, because the shutter 110 is disposed at a distance from the aperture 108, superfluous water can get from above via the shutter directly to the outflow 107. Similarly, an inflow shutter 104 is placed at a distance from the inflow aperture 106, the effect of which is that the speed of the inflowing water decreases and the small stones and sand, which are carried along, fall down into portion 117. The dirt free water gets directly through the opening of the shutter 104 into the shaft and can leave it again opposite the latter.

To prevent any of the solid matter washed in through the inlet 105 from escaping, on the entry side of the first portion 117 there is fastened or moulded a baffle 118 to its upper wall 120.

The container or housing 103 can be emptied in a simple way and the small stones and sand 129 deposited there can be removed. For this purpose, the first portion 117 can be swivelled clockwise in the direction of arrow P round a horizontal axis B (Fig. 8). The first portion 117 does not have to be taken out of the container 103, but it comes to a stop in a parallel position to the shutter 110 and thus leaves the largest 1 portion of the container and housing cross-section free.

Figure 9 shows, in cross-section, portion 117, designed as a channel, with the upper wall 120.

11 n

Claims (1)

1. A device for the continuous separating of sand and stones out of a pipeline, said device being located in a collecting chamber between an inflow and an outflow of said pipeline, characterised in that the inflow and the outflow are connected to one another by a pipeline section serving as a separator, the pipeline section having, on the inflow side, a first portion running downwards to the horizontal and, on the outflow side, a second portion running upwards, an opening being provided at the common lowest part of such portions.

   2. A device as claimed in claim 1, characterised in that the first portion has a smaller incline than the second portion.

   3. A device as claimed in claim 1 or 2, characterised in that the cross-section of the first and second portions is smaller than the cross-section of the inflow.

   4. A device as claimed in claim 2 or 3, characterised. in that the first portion is substantially longer than the second portion.

   12 5. A device as claimed in any preceeding claim characterised in that the entrance to the first portion is disposed in the region of the inflow and the exit from the second portion back into the pipeline section is arranged in the region of the outflow.

   6. A device as claimed in claim 5, characterised in that a deflector is disposed on the side turned away from the inflow of the entrance to the first portion.

   is 7. A device according to claim 1, characterised in that the pipeline section is designed as a V-shaped trough, the lower boundary walls of which are formed by the two portions.

   8. A device as claimed in claim 7, characterised in that the trough has an opening at the deepest point.

   9. A device as claimed in any one of claims 1 to 4, characterised in that the first portion consists of a channel, closed on the top by a wall.

   10. A device as claimed in claim 9, characterised in that the first portion can be swivelled round a horizontal axis.

   13 11. A device as claimed in claim 9 or 10, characterised in that a baffle is arranged at the end of the first portion on the inflow side.

   12. A device for the continuous separating of sand and stones out of a pipeline, substantially as hereinbefore described with reference to the accompanying drawings.