GB2544532A

GB2544532A - Improvements relating to lateral pipes

Info

Publication number: GB2544532A
Application number: GB1520469.6A
Authority: GB
Inventors: Henou Abbas Alaa
Original assignee: Individual
Current assignee: Individual
Priority date: 2015-11-20
Filing date: 2015-11-20
Publication date: 2017-05-24
Anticipated expiration: 2035-11-20
Also published as: GB2544532B; GB201520469D0

Abstract

A combined waste conduit comprising a sewerage pipe 10 having a hollow body 12 with an upper and lower semi-circular conduit 14, 16 defined by a dividing wall 18 seperating the two, the dividing wall forming the lower wall of the upper conduit and the upper wall of the lower conduit. Two pipes are in fluid communication with the upper and lower conduit respectively allowing the passage of waste and sewage water separately whilst reducing the surface area of the system, reducing the installation time.

Description

IMPROVEMENTS RELATING TO LATERAL PIPES

The present invention relates to apparatus and a method for separating sanitary effluent from storm water - in a sewer system.

Typically, sewer systems include a network of pipes that convey wastewater from homes, businesses and industries to treatment plants and storm water from drains to infiltrate into flood plains, held on the surface to evaporate or directed to nearby streams, rivers or coastal waters. A lateral sewer serving one or a small number of street; a submain collects sewage from two or more lateral sewers and discharges in to a main. The main then discharges into a trunk. From the trunk, the wastewater is sent to the wastewater treatment plant.

There are a few principal designs for systems to carry sewerage and stormwater: a separate system; a combined system; and a partially separate system.

In a separate system, rain water is kept separate from sewage. In a combined system, one set of pipes takes both sewerage and rain water. The advantages of a separate system is that the load on treatment units becomes less as the volume of material to be treated is limited to just sewerage, the natural water is not unnecessarily polluted as it is kept in a separate pipe, the sewers may be small in size as they simply accommodate sewerage, storm water can be discharged into natural streams without any treatment and where pumping is required for the lifting of sewage.

Advantages of a separate system include that there is no need for a combined sewer overflow as only wastewater is delivered to the treatment plant; all storm water is carried separately to outfall. Consequently, smaller wastewater treatment works are necessary as the volume of material to process will be less than in a system where storm water also requires processing. The wastewater sewer can be kept to the optimum size to ensure sufficient velocity even at low flows. Flooding will be by storm water only as the wastewater is kept separate thereto.

Disadvantages of a separate system include the extra cost of laying and maintaining two pipes. Additional space is required to accommodate both pipes which can be extremely difficult in built up areas or narrow streets. There are more house connections required with greater risk that an incorrect connection is made which can result in storm water pipes being contaminated by wastewater. There is no flushing of wastewater solids by stormwater and there is no treatment of stormwater.

Advantages of a combined system include lower costs for pipe construction as there is simply one pipe to construct and lay. The space occupied by the single pipe is smaller than with having to lay two pipes in a separate system and so is better suited to built up areas or narrow streets. House drainage is simpler and cheaper and there is no risk with confusing which pipe is which. Deposited waste water solids will be flushed out in heavy storms and at least some stormwater will be treated.

Disadvantages of a combined system include the necessity for combined sewer overflow to keep main sewers and treatment works to feasible sizes and serious pollution to watercourses may occur. Larger treatment works are necessary to handle the volume of wastewater combined with storm water. Slow, shallow flow in large sewers in dry weather may cause deposition of solids in pipes. If flooding occurs, foul conditions will be caused.

Known separate systems might include a pipe for wastewater and a pipe for stormwater. The stormwater lateral pipe is likely to be 250 mm diameter and the wastewater lateral pipe 200 mm in diameter as a minimum pipe diameter according to common practice. The volume required to accommodate such conduits is great and the cost associated with digging a sufficiently deep enough trench to accommodate the conduits is also significant.

In accordance with an aspect of the present invention, there is provided a combined waste conduit for conveying storm water and waste water having a body comprising a first and second conduit separated from one another by a dividing wall integral to both the first and the second conduit.

Originally, a single system of pipes known as a combined system was used to convey both surface and polluted water (one pipe to convey both sanitary sewage and storm water).

In new developments two sets of pipes were used, surface-water sewers for the rainfall drained form paved and roofed areas and sanitary sewers for polluted water, this is known as the separate system. In order to save some of the extra expense of a completely separate system, a compromise known as the partially separate system was adopted in some areas. On this system, surface-water sewers deal with the greater part of the road and roof drainage while a second set of pipes takes all the polluted water together with surface water from yards and rear roofs, which are close to the sources of polluted water.

Although separate sewer systems is more protect for Environment and watercourses, but Economical factor is considered an important aspect in the design of separate sewers system because it is more expensive than combined sewer system.

This innovation system for the sewer networks will include a proposed new design for shape of pipe, which will allow the storm flow and the sewage flow to pass through the same pipe has two sections without mixing. This will have the advantages of a combined sewer system and a separate sewer system in one system, comply with the 21st century requirements (sustainability, protection of public health, and reduce cost), as one trench will be used for one pipe with two sections (storm section and sanitary section).

Applying this system in the design of residential district area results will come with many advantages. 1. Protection of the Environment

The separation of storm and sewage water is one of the main advantages of this system. This is due to the many inconveniences that occur when storm and sewage water are mixed and most of the overflow goes to watercourses, which has a very negative impact on water quality and affects the ecosystem (aquatic life) and health of the public. 2. Economic Consideration

It is clearly shown that when this system used in a sewer network it decreases the overall construction costs in comparison with the construction cost resulting from using the separate system as it will use one trench for set the one pipe with two sections (storm pipe section and sanitary pipe section). 3. Area Occupied by the System

This innovation system will decrease the surface areas used in excavation, which means less effect on activities in the community and traffic (less dust, noise, erosion and disruptions to residents and businesses), and construction of separate sewers is difficult and costly when the areas have narrow roads and streets, this innovation system will be the best solution in this case. 4. Time for Installation

The time factor is very important when executing a network system as affects the cost of construction. The innovation system will reduced the total time of construction.

As the economic factor is considered to be an important aspect in the design of a separate sewer system, therefore a great deal of emphasis has been given to develop a sewer system through this innovation system that is suitable in terms of the environment, economy and hydraulics.

This innovation system is combines the advantages of the combined, separate system by using a new shape for lateral pipe.

In accordance with another aspect of the present invention there is provided a combined waste conduit for conveying storm water and waste water effluent comprising: - a body having a side wall defining two conduits divided by an internal separating wall; - the first conduit is for conveying storm water and the second conduit is for conveying waste water; wherein the separating wall forms the lower face of the first volume and the upper face of the second volume

In accordance with another aspect of the present invention there is provided a combined waste conduit for conveying storm water and waste water comprising: a first conduit is for conveying storm water and the second conduit/internal volume is for conveying waste water; wherein the first conduit is defined by a side wall whose outer surface at least partially defines the second conduit.

Each of the first and second volumes or conduits do not extend through the other.

The method according to the present invention includes the steps of: a. providing a first set of sewer lines connected between at least one source of storm water, and/or source of infiltrated water, and an open drain; b. providing a second set of sewer lines connected between a source of sanitary effluent and a sewerage treatment plant. A sewer system according to the present invention reduces the cumulative volume and thus size of the pipes required to carry sanitary effluent and/or increases the capacity of the sewerage treatment plant to treat sanitary effluent. Since the storm water water are separated from the sanitary effluent, they may require little or no treatment freeing plant capacity to treat the sanitary effluent.

The conduit may be manufactured from any suitable material that can be used in existing sewer pipes, including: Concrete, PVC and UPVC, GRP, HDPL, Clay, Cast Iron, ductile. A method of installing the apparatus according to the present invention includes the steps of excavating an open trench; laying the combined waste conduit as described hereinabove; connecting the upper conduit to a storm water pipe and connecting the lower conduit to a waste water pipe.

An alternative method replaces excavating an open trench and instead relies on tunnelling techniques to put the pipe into position. Such trenchless methods avoid disruption on the surface.

The present invention benefits from the advantages of a traditional combined system in only having to dig a single trench or tunnel with the advantages of a separate system, as outlined above.

The present invention relates generally to an apparatus and a method for separating sanitary effluent from storm water in a municipal sewer system.

In an embodiment, the second conduit is disposed below the first conduit.

The present invention will now be described by way of example only with reference to the accompanying drawings, in which:

Fig. 1 is a conduit in accordance with the present invention;

Fig. 2 is a conduit in accordance with the present invention;

Fig. 3 is an enlarged view of the junction between two conduits;

Fig. 4 is a view of two conduits in accordance with the present invention;

Fig. 5 is another embodiment of a conduit in accordance with the present invention; and Fig. 6 shows the conduits in situ and connected to storm water drains and wastewater outlets from houses.

Fig. 1 shows a sewerage pipe 10 having a hollow body 12 having an upper and lower semicircular chamber 14 and 16 open at either end and separated by a dividing wall 18.

The upper face 20 of the dividing wall 18 is substantially v-shaped in cross section, inclined from the centre towards both sides to form a centrally disposed channel which is intended to encourage better flow of material through the conduit. The angle of incline from the centre of the upper face to the sidewall is between 3 and 10 degrees. This improves the velocity of the material moving through the conduit.

The lower conduit carries material generally on its inner face of the curved section of the semi-circular chamber. A cross sectional view shows that the upper conduit has a larger circumference than the lower chamber resulting in a ledge/overhang which forms a support in use to help maintain the pipe in correct orientation when installing and during use. The overhang provides a platform for the conduit when in situ. Disposed at one end and half way along the length are supports 30 32 respectively. Support 30, 32 have a planar base 34, 36 and two side walls 38, 40 and 38', 40' extending perpendicularly to the base 34, 36 and which meet and are flush to the overhanging side wall of the upper conduit. The upper conduit might have a volume equivalent to a pipe that is about 200mm - 250mm in diameter, whilst the lower conduit might have a volume equivalent to a pipe having a diameter that is about 150 - 200mm in diameter. The volume according to the smaller diameter above might be for a small number of domiciles whilst the larger volume might be for a line further downstream from such domiciles, for use where significant increases in flow rate is anticipated or where there is the need to connect to a multistage building which will most likely have a 150 mm diameter connection pipe (50)(160).

The upper conduit has a pipe 40 in fluid communication such that material can flow through the pipe into the conduit 14. The pipe may have a 'y' shaped connector 42 attached thereto to connect to storm drains. The connector 42 may also have a capped inlet 44 closed by a cap 46 to facilitate easy maintenance to clear blockages or the like. The branches of pipe 42 can be connected to storm drains either side of a street or can be connected to one side of a road to received storm water from the drain and storm water from a building's guttering.

Cover 46 covering inlet 44 may be found at the street surface to facilitate easy access for cleaning and/or inspection.

In an embodiment (Fig. 2), the lower conduit 16 has a pipe 50 in fluid communication such that material can flow through the pipe into the conduit 16. The pipe is disposed adjacent to the support 32 to provide better structural integrity to the pipe 50 and prolong the life of the pipe. The pipe connected to the lower conduit might be connected to a waste water pipe from a building.

The diameter of pipe 42 might be about 200 mm and the diameter of the branch pipes might be about 150mm. The diameter of the pipe 50 might be about 100 to 150mm. Having dissimilar diameters for the pipes connected to the upper conduit for storm water and the lower conduit for waste water, then it is less likely that there will be misconnection of waste water pipes to the storm water conduit and vice versa. It will be immediately clear to the engineer installing the conduit as to which pipe to connect to which conduit of the present invention thus avoiding contamination of storm water via waste water which will go untreated and be expelled into natural watercourses.

The upper and lower conduits are stepped such that at one end there is an overhang of the upper conduit over the lower. At the other end the lower conduit extends beyond the upper conduit such that when two pipes are connected, it is more straightforward to connect and seal pipes together, there is no need for a specific separate connector to receive ends of adjoining pipes rather adjoining pipes are able to be connected directly with one another. (Fig. 3) One end of a first pipe has an elongate transverse slot 60 disposed in the dividing wall 18 whilst a second pipe has a complementarily shaped planar tongue 62 which is received by the slot. These ensure correct alignment of adjacent pipes and improves the integrity of the joint formed therebetween.

Fig. 4 shows a first and second pipe in close proximity about to be connected to one another. Having the pipes connected to the upper and lower conduits spaced apart as shown helps prevent accidental mis-connection with waste water and stormwater pipes.

The average pipe length in typical applications is 5m.

In an embodiment, shown in Fig. 5, there is a first pipe 100 having an upper conduit 102 and a lower conduit 104 arranged below. The upper conduit 102 has a tubular body 106 partially defined by a sidewall 108 and is open at both ends.

The lower conduit 104 is defined by the lower part of sidewall 108 and has an elongate body 108 of generally U-shaped cross section. The cross section of side wall 108 is generally egg shaped. It's length corresponds to that of the upper conduit only they are staggered such that there is an overhang at one end of the pipe whilst at the other end, the lower conduit extends beyond the upper conduit to facilitate easier connecting of adjacent pipes and avoid as far as possible leak from upper conduit (106) to lower conduit (108).

Disposed at the ends of the lower conduit and part-way along its length, equidistant between the ends, are support members 110, 112 and 114. The supports provide a planar platform which will help the lower conduit better remain in an orientation when in situ. The supports have a planar base 120 and side walls 122,124 which extend perpendicularly from the base. The upper conduit is received by the lower conduit to form a seal between the sidewalls of both conduits to prevent material flowing through the lower conduit from passing therethrough.

The overhang 130 of the upper conduit is received by the extension of the lower conduit 132 beyond the upper conduit such that support members 110 and 112 abut one another and form a stable support for the conduits. Adjacent pipes may be sealed using a rubber seal in addition to the tongue and groove described above.

Extending in the first pipe from the upper conduit is a pipe in fluid communication such that material can flow through the pipe into the conduit 102. The pipe has a Ύ shaped connector 142 attached thereto to connect to storm drains. The connector 142 may also have a capped inlet 144 closed by a cap 146 to facilitate easy maintenance to clear blockages or the like.

Also shown is a second pipe 150, the lower conduit 104 of which has a pipe 160 in fluid communication such that material can flow through the pipe into the conduit 104. The pipe is disposed adjacent to the centrally disposed support 162 to provide better structural integrity to the pipe 160 and prolong the life of the pipe.

The system is designed to ensure that no mixing of storm and sewage will take place. Fig. 6 shows the conduits connected to stormwater drains 200 and houses 202.

Later in the trunk line, the system will split to be a separate system, one trunk line for transporting the sewage flow to treatment plant while the storm pipe sections collect by a trunk pipe end in watercourses or effluent directly to watercourses.

Claims

1. A combined waste conduit for conveying storm water and waste water having a body comprising a first and second conduit defined by a side wall and separated from one another by a dividing wall integral to both the first and the second conduit.

2. A combined waste conduit for conveying storm water and waste water comprising: - a body having a side wall defining two conduits separated by an internal separating wall; - the first conduit for conveying storm water and the second conduit for conveying waste water; wherein the separating wall forms the lower face of the first volume and the upper face of the second volume.

3. A combined waste conduit for conveying storm water and waste water comprising: a first conduit for conveying storm water and the second conduit is for conveying waste water; wherein the first conduit is defined by a side wall whose outer surface at least partially defines the second conduit.

4. A conduit as claimed in anyone of the preceding claims wherein each of the first and second conduits do not extend through the other.

5. A conduit as claimed in any one of the previous claims wherein the first and second conduits are cenaraterl hi/ a rlix/irlina \*/all

6. A conduit as claimed in any one of the previous claims wherein the first conduit is in fluid flow connection with a first pipe and the second conduit is in fluid flow connection with a second pipe, and wherein the first and second pipes are integrally formed therewith.

7. A conduit as claimed in claim 5 wherein the dividing wall is declined on at least one side towards the centre of the conduit.

8. A conduit as claimed in claim 7 wherein the angle of decline is between 3 and 10 degrees.

9. A conduit as claimed in claim 6 or 7 wherein the upper face of the dividing wall has substantially v-shaped profile.

10. A conduit as claimed in any one of the previous claims having integral support means.

11. A conduit as claimed in claim 10 wherein the integral support means are provided by the first conduit sidewalls.

12. A conduit as claimed in claim 11 wherein the first conduit has a larger circumference than the second conduit and has overhanging sidewalls.

13. A conduit as claimed in any one of the previous claims wherein the first and second conduits are stepped such that at one end of the conduit there is an overhang of the first conduit over the second and at the other end the second conduit extends beyond the first conduit.

14. A conduit as claimed in any one of the previous claims wherein the first conduit has a tubular body open at both ends and the second conduit has an elongate body of generally v-shaped cross section forming a channel for receiving the first conduit.

15. A conduit as claimed in claim 14 wherein the second conduit has at least one support member for supporting the conduit in position.

16. A conduit as claimed in claim 15 wherein the at least one support member comprises a planar base and side walls which extend perpendicularly from the base.

17. A conduit as claimed in any one of claims 14 to 16 having mating means for connecting adjacent conduits.

18. A conduit as claimed in claim 17 having at one end a tongue and at the other a slot wherein the tongue of an adjacent conduit is received in the slot.

19. A conduit as claimed in anyone of the previous claims wherein the first conduit has a pipe for receiving storm water associated therewith and in fluid communication with the first conduit.

20. A conduit as claimed in any one of the previous claims wherein the second conduit has a pipe for receiving waste water associated therewith and in fluid communication with the second conduit.

21. A conduit as claimed in any one of the previous claims comprising a first conduit having a volume equivalent toa pipe of the same lengthand having a diameter between 200-250mm.

22. A conduit as claimed in any one of the previous claims comprising a second conduit having a volume equivalent to a pipe of the same length and having a diameter between 100mm -150mm.

23. A conduit as claimed in anyone of the previous claims wherein the first conduit is disposed above the second conduit.