Classifications

• • E—FIXED CONSTRUCTIONS
  • E03—WATER SUPPLY; SEWERAGE
  • E03F—SEWERS; CESSPOOLS
  • E03F3/00—Sewer pipe-line systems
  • E03F3/02—Arrangement of sewer pipe-lines or pipe-line systems
• • E—FIXED CONSTRUCTIONS
  • E03—WATER SUPPLY; SEWERAGE
  • E03F—SEWERS; CESSPOOLS
  • E03F3/00—Sewer pipe-line systems
  • E03F3/04—Pipes or fittings specially adapted to sewers
• • E—FIXED CONSTRUCTIONS
  • E03—WATER SUPPLY; SEWERAGE
  • E03F—SEWERS; CESSPOOLS
  • E03F5/00—Sewerage structures
  • E03F5/10—Collecting-tanks; Equalising-tanks for regulating the run-off; Laying-up basins
  • E03F5/105—Accessories, e.g. flow regulators or cleaning devices
  • E03F5/106—Passive flow control devices, i.e. not moving during flow regulation
• • E—FIXED CONSTRUCTIONS
  • E03—WATER SUPPLY; SEWERAGE
  • E03F—SEWERS; CESSPOOLS
  • E03F5/00—Sewerage structures
  • E03F5/10—Collecting-tanks; Equalising-tanks for regulating the run-off; Laying-up basins
  • E03F5/105—Accessories, e.g. flow regulators or cleaning devices
  • E03F5/108—Cleaning devices providing a flushing surge
• • E—FIXED CONSTRUCTIONS
  • E03—WATER SUPPLY; SEWERAGE
  • E03F—SEWERS; CESSPOOLS
  • E03F5/00—Sewerage structures
  • E03F5/20—Siphon pipes or inverted siphons
• • E—FIXED CONSTRUCTIONS
  • E03—WATER SUPPLY; SEWERAGE
  • E03F—SEWERS; CESSPOOLS
  • E03F9/00—Arrangements or fixed installations methods or devices for cleaning or clearing sewer pipes, e.g. by flushing
  • E03F9/007—Devices providing a flushing surge

Definitions

• Gravity sewer device self-flushing inverted siphons, ithod of overcoming watercourses or similar underground obstacles and use of this device
• the invention relates to a gravity sewer device for overcoming watercourses or similar underground obstacles, so-called inverted siphons consisting of one or more inlet shaft chambers with an automatic flushing bell, connected to a descending leg of a sewer conduit, crossing an ascending leg of a sewer conduit and an outlet shaft, wherein the automatic flushing bell ensures the filling and emptying of the working volume of the shaft, and the waste water is periodically discharged under increased pressure and at high speed into the sewer conduit of the inverted siphon.
• the standard arrangement of the sewer inverted siphon is shown in Fig. 1.
• the wastewater flows through the gravity conduit 1 at the flow rate Q(0) into the upper inlet chamber 2, which forms the transition from the sewer conduit to the inverted siphon.
• the inverted siphon itself consists of the descending conduit leg 3, a horizontal, reap, slightly inclined part forming the crossing 5 under the watercourse 4 or a similar underground obstacle, and the ascending conduit leg 6.
• the inverted siphon leads to the lower outlet shaft chamber 7, which must always be located lower than the upper inlet chamber.
• the wastewater flows out of the shaft chamber 7 through the gravity conduit 8 at the flow rate Q(0).
• the solutions can be divided into two basic groups.
• the first group consists of solutions that work with the creation of a narrowed point of entry into the inverted siphon and controlled suction of air so as to create a so-called air cushion in the legs of the inverted siphon. This reduces the cross-section of the inverted siphon conduit, which increases the flow rate.
• the disadvantage of the group of solutions with the air cushion is their technical complexity and thus operational unreliability. Representative of this group of solutions is, for example, JP2006063645A, whose authors are Koda Yoshiharu and Odaka Shiro.
• the second group comprises solutions that work with periodic filling of the inlet chamber of the inverted siphon, where the outlet chamber of the inverted siphon has a mechanical conduit closure. It opens in a controlled or automatic manner depending on the state of the water level in the inlet chamber or the water pressure in the outlet chamber.
• the inverted siphon conduit is always filled with water, i.e., without any air cushion.
• This group is also problematic due to the technical complexity, so it is used mainly for large-diameter inverted siphons.
• the objective of the invention is to eliminate the disadvantages of the prior art and to create a simple and operationally reliable sewer system which will be able to function even at a very low flow rate Q(0) without the risk of the crossing conduit clogging under a watercourse or similar underground obstacle.
• This invention uses a known solution of the Miller flush bell, disclosed in US727990A, US710703A and US761316A.
• the Miller flush bell for use in inverted siphons has been innovatively modified according to exemplary solutions 1 and 2 so as to be able to work in a system of the new technical solution of a self-flushing inverted siphon, which is a modification of the Miller flush bell, hereinafter referred to as the automatic flushing bell 17.
• the Miller flush bell has been further innovatively modified according to exemplary solutions 3 and 4, which is a variant of the automatic flushing bell, hereinafter referred to as the automatic flushing bell 20.
• the self-flushing inverted siphon according to the invention forms a section of a gravity sewer, which crosses a watercourse or a similar underground obstacle, is graphically shown in Fig. 2 and compared with the classic design of the inverted siphon in Fig. 1. It consists of one or more inlet shaft chambers 9 connected to the descending leg 12 of the sewage conduit, the crossing 13, the ascending leg 14 of the sewage conduit and the outlet shaft 7, wherein the automatic flushing bell 17 or 20 is located in the inlet shaft chamber 9.
• the gravity sewer of the inlet 1 is connected to the inlet of the inlet shaft chamber 9, which is equipped with a space for trapping sand and coarse sediments 10, a bar screen or a screen basket 11.
• the gravity sewer of the outlet £ is connected to the outlet shaft 7.
• the wastewater flows at the flow rate Q(0) through the gravity conduit 1 into the upper inlet chamber 9, equipped with a sand trap 10 and a floating impurities catcher 11.
• the automatic flushing bell 17 (alternatively as variant 20), which includes a siphon conduit 15 and a vent pipe 16, provides periodic alternation between two phases, water accumulation and transfer, when the water level in the storage space of the chamber 9 oscillates between H1 and H2, where the filling velocity (flow rate) is Q(0), and the transfer velocity (resp. flow rate) is Q(l).
• the design of the accumulation volume of the main part of the inlet chamber 9 must be carried out in accordance with the total volume of the sewage conduit of the inverted siphon. It must be at least 1.5 times greater than the inverted siphon volume. it has proven to be an advantageous solution to use an automatic flushing bell 17 or 20 for the conduit dimensions and the difference between the upper and lower water level height limits H2-H1: internal diameter DN100 for H2-H1 from 0.2 to 0.6 m internal diameter DN150 for H2-H1 from 0.6 to 0.7 m internal diameter DN200 for H2-H1 from 0.7 to 1.0 m
• An advantageous solution has proven to be to design the accumulation volume of the main part of the inlet chamber to be at least 1.5 times greater than the volume of the inverted siphon conduit.
• non-corroding materials e.g., polypropylene, polyethylene, stainless steel AISI 316L
• materials such as HOPE or cast iron commonly used for pressure conduits can be used for the inverted siphon conduit.
• the automatic flushing bell 17 is defined as a complete constant device for switching with a constant level described in Examples 1 and 2, the bell 17a being a part of it in the form of a single-stage inverted bell, described in said examples and shown in detail in Fig. 3.
• the automatic flushing bell 20 is defined as a complete device for switching with a variable and controlled level described in Examples 3 and 4, the bell 17b being a part of it in the form of a two-stage inverted bell, described in said examples and shown in detail in Fig. 4.
• Fig. 1 shows a standard technical solution of a sewer inverted siphon under a watercourse
• Fig. 2 shows a technical solution of a self-flushing inverted siphon according to the invention, with an automatic flushing bell 17, described in Example 1;
• Fig. 3 shows the individual parts of the automatic flushing bell 17 for the description of its function in Example 2;
• Fig. 4 shows the individual parts of the automatic flushing bell 20 for the description of its function in Example 3;
• Fig. 5 shows schematically the function of a sequencing batch reactor using the automatic flushing bell 20, the solution being described in Example 4;
• Fig. 6 shows the dependence of the pressure loss of the inverted siphon conduit from Example 1 and the flow rate according to the Colebrook-White equations.
• the inverted siphon for overcoming a watercourse or similar underground obstacles according to the invention a self-flushing inverted siphon, is shown in Fig. 2.
• the self-flushing inverted siphon consists of an upper inlet chamber 9, to which a gravity sewage pipe 1 is connected.
• the upper inlet chamber is equipped with a space for collecting sand and coarse sediments 10, with bar screens or a screen basket 11.
• an automatic flushing bell 17 In the main part of the inlet chamber there is situated an automatic flushing bell 17.
• the siphon conduit 15 of the automatic flushing bell 17 is connected to the descending leg 12 of the sewage inverted siphon conduit, then to the crossing conduit 13 of the watercourse 4, the ascending leg of the sewage conduit 14_ from where it then leads into the lower outlet sewer shaft 7.
• the gravity sewage conduit 8 is connected to the sewer shaft 7.
• the design of the accumulation volume of the main part of the inlet chamber 9 must be carried out in accordance with the total volume of the sewage conduit of the inverted siphon. It must be at least 1.5 times greater than the inverted siphon volume.
• water temperature T 20°C
• density o 998 kg.m -3
• kinematic
• the working area of a specific inverted siphon is therefore between points WP1 and WP2.
• the values enable you to approximate the mean outflow velocity, the average flow rate and subsequently to calculate the emptying time of the inlet chamber of the inverted siphon.
• Fig. 3 shows the complete assembly of the automatic flushing bell 17, which consists of the original siphon conduit 15 with the bell 17a fitted.
• the assembly was supplemented with a side closing pipe 18 for adjusting the level height H3 and a vent pipe 16.
• the tank is filled with water from the water level H1 (lower-level height limit) at the same rate inside and outside the bell 17a, until the water level H3 is reached.
• the rising water covers the side closing pipe 18, the tank continues to fill up to level H2, with different velocities inside and outside the bell 17a, the water level in the storage tank is open to the atmosphere, the water level inside the bell 17a is not.
• the rise in water between H3 and H2 causes an increase in the air pressure inside the bell 17a, which causes the water to drop towards the siphon 15.
• the water in the siphon 15 drops to the H5 level, the H2 level is just reached in the storage tank as the upper-level height limit.
• the filling and accumulation phase ends, the water transfer phase begins.
• the overpressure in the tank causes the water to be forced into the conduit 25, the excess air escapes into the atmosphere through the pipe 16, the water column and the "siphon effect" start are connected, the tank starts being emptied.
• a new period, the filling and accumulation phase, begins, from the water level height H1 in the tank.
• the automatic flushing bell 17 in Example 2 is suitable for applications where fixed setting of the switching level H2 is sufficient.
• Example 3 a separate innovative modification is described, which results in a variant according to the second embodiment, i.e., an automatic flushing bell 20 with the variable switching level Hx:
• the bell 17b having a cylindrical and a conical part (the bell 17a only has a cylindrical part) is mounted on a siphon conduit 15 with a vent pipe 16 and is supplemented by a side closing tube 18.
• the conical portion of the bell 17b may have a deflector 24 at the bottom, which is a baffle plate with directing lamellae to increase the absorption capacity of the automatic flushing bell and change the direction of water 27 being sucked in.
• the suction direction 27 is shown in detail on the deflector 24 in Fig. 4.
• the tank is filled with water starting from the water level height H1 (lower-level height limit) at the same rate inside and outside the bell 17b, until the water level height H3 is reached, and after the side closing tube 18 has been covered, the tank continues to be filled.
• H1 lower-level height limit
• H3 water level height
• side closing tube 18 after the side closing tube 18 has been covered, the tank continues to be filled.
• the automatic flushing bell 20 in Example 3 can be used as a separate technical solution of the invention for discharging water from a sequencing batch reactor, which is shown in Fig. 5:
• the tank 1_9 is equipped with a discharging station 29 for replenishing water in the tank 19, further with a blower 28 for supplying compressed air for the aeration device 31, by means of the device for controlled discharge of separated clean water the automatic flushing bell 20, described in Example 4.
• the sequencing batch reactor is supplemented by a control system 30 with connected digital inputs il to i3 for sensing the water level H7, H8 resp. H9, which is ensured by means of a level sensor 23.
• the control is performed in a combination of volume and time mode via digital outputs ol to o3, when the output ol switches on, resp. switches off the blower 28, the outlet o2 switches on/off the discharging station 29, and the outlet o3 carries out decompression in the bell 17b of the automatic flushing bell 20 through the solenoid valve 22, so that the outlet o3 opens the solenoid valve 22, thereby releasing air from the bell space 17b and siphon conduit 15, and subsequently the water continuum is connected. This then triggers the siphon effect when the filling phase ends, and the tank starts being emptied.
• the automatic flushing bell 20 in the sequencing batch reactor is always supplemented with a deflector 24 to increase the absorption capacity, to provide water suction 27 direction control and prevent suction of settling particles 24 in the automatic flushing bell 20, and is described in Example 4 and shown in Fig. 4, including the P'- P sectional view in the detailed ground plan.
• phase F1 - filling and simultaneous biological reaction pump station 29 and blower 28 are on
• phase F2 - sludge sedimentation (blower 28 is off)
• phase F3 - decantation and water discharge
• phase F2 For phases F1 and F3, the volume control of the automatic flushing bell 20 can be successfully used, phase F2 must be strictly time controlled. Usually, a 60-minute sedimentation period is used in one cycle, where sedimentation means switching off the blower 28 and interrupting water discharging from the pumping station 29.
• the control system 30 switches off the blower 28 via the digital output ol for the required 60-minute period, then the control system 30 opens the solenoid valve 22 via the digital output o3 for 10 to 15 seconds. This depressurizes the automatic flushing bell 20 at point 21, via line 26 through the solenoid valve 22 from point 21, which connects the water column inside the bell 17b and at the same time the F3 phase begins, the clean water being discharged until the H7 level is reached. The entire three-phase cycle of the sequencing reactor then starts again.
• the devices according to the invention can be particularly used in the field of wastewater transport and treatment.
• Example 4 il, i2, i3 - digital inputs of the control system 30 ol, o2, o3 - digital outputs of the control system 30

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• Health & Medical Sciences (AREA)
• Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Hydrology & Water Resources (AREA)
• Public Health (AREA)
• Water Supply & Treatment (AREA)
• Jet Pumps And Other Pumps (AREA)
• Sewage (AREA)

Applications Claiming Priority (2)

Publications (1)

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ID=77411976

Family Applications (1)

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• 2020
  • 2020-07-07 CZ CZ2020-394A patent/CZ2020394A3/cs unknown
• 2021
  • 2021-07-07 EP EP21758131.3A patent/EP4179161A1/en active Pending
  • 2021-07-07 WO PCT/IB2021/000437 patent/WO2022008969A1/en not_active Ceased

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