AU655111B2

AU655111B2 - Well cleaning system

Info

Publication number: AU655111B2
Application number: AU39856/93A
Authority: AU
Inventors: Douglas Brett Mccasker
Original assignee: Davies Bradley Kent; Jackson & Lee Sales Pty Ltd
Current assignee: Davies Bradley Kent; Jackson & Lee Sales Pty Ltd
Priority date: 1992-05-27
Filing date: 1993-05-27
Publication date: 1994-12-01
Anticipated expiration: 2013-05-27
Also published as: AU3985693A

Description

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AUSTRALIA

Patents Act 1990 ir C U Name of Applicant DOUGLAS BRETT McCASKER Actual Inventor DOUGLAS BRETT McCASKER Address for Service GRANT ADAMS COMPANY, Patent Trade Mark Attorneys Level 9, National Mutual Centre, 144 Edward Street, BRISBANE. QLD. 4000

AUSTRALIA.

Invention Title WELL CLEANING SYSTEM Details of Associated Provisional Applications Numbers PL2633 The following statement is a full description of the invention including the best method of performing it known to me.

THIS INVEUTION relates to a cleaning system for wells.

The term "well" shall include sump wells, sumps, collection tanks, holding tanks, grease traps and the like.

Sewage systems are in universal use for removal of human and other waste materials from dwellings, industrial premises and other places frequented by people. The waste materials are carried by water flowing through pipes or conduits to sewage treatment plants. Problems occur in the system if the rate of flow of liquid in the conduit is too low. To maintain the rate of flow above critical levels, sewage pumps are widely used. These pumps are eleztrically 15 operated and are installed automatically operated by either float switches, proximity switches or probes.

When the liquid in a well reaches a predetermined level, the pump is switched on and when the liquid falls to a predetermined level, the pump switches off. As the level in the well falls, a residue of fats and other substances is left on the walls of the well, between the high and low liquid levels. This residue builds up and °tooreduces the efficiency of the system, causes damage to the pumps and creates foul odours. In many sewage 25 systems, this residue is cleaned off manually. This is expensive and hazardous work.

o It is an object of the present invention to Sprovide a cleaning system which removes the residue from the walls of the well or tank.

It is a preferred object to provide such a system which will remove the residue before it is allowed to dry and harden, as the liquid level falls.

It is a further preferred object to provide a cleaning system which is automatically operated when the pumps are operated.

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Other preferred objects will become apparent from the following description.

In a broad aspect, the present invention provides cleaning system for wells (as hereinbefore defined) including: a support frame mountable on a wall of the well; a rotor assembly rotatably mounted on the support frame rotatable about an axis substantially parallel to the wall, or the vertical axis, of the well; a plurality of spray jet nozzles on the rotor assembly, directed towards the wall; supply means for directing liquid under pressure to the spray-jet nozzles; and means for rotating the rotor assembly; so arranged that as the rotor assembly is rotated, liquid sprayed from the spray jet nozzles washes residue or wastes down the wall.

The support frame may include at least one arm, pivotally mounted on this wall, and optionally telescopic, to enable the system to be positioned adjacent the wall for access to the bottom of the well.

Preferably, the arm supports the rotor assembly for rotation about the vertical axis of the well.

Preferably, the rotor assembly has a tubular rotary shaft sealably journalled in a. rotary hub on the distal end of the support arm, the hub having an inlet fitting connectable to the supply means..

Preferably, at least two spray arms radiate from the rotary shaft and the spray-jet nozzles are provided at or adjacent their distal ends. Fine misting nozzles may be provided along the spray arms.

Preferably, the spray-jet nozzles are arranged to spray the liquid in a band about the wall which includes the level at which the pump(s) in the well are 01-P

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Preferably, the spray-jet nozzles are inclined in plan view to generate the rotary drive for the rotor assembly.

In one preferred embodiment, the supply means for the liquid is a reticulated water supply having a reduced pressure zone valve and a solenoid valve, the latter being operable to supply water to the cleaning system when the pump(s) in the well are switched on.

In a second preferred embodiment, the supply means is a (preferably submersible) pump which draws liquid from the waste in the well (via suitable oo filtration means), the pump being operable when the *0 pump(s) in the well are switched on.

15 To enable the invention to be fully understood, preferred embodiments will now be descriLed with reference to FIG 1 of the accompanying drawings which shows: a sectional side view. (not to scale) of a S'first embodiment in solid lines and a second embodiment in dashed lines.

The sewage well 10 has a primary _ump 11 and secondary pump 12 at its base.

The liquid level. 13 in the well 10 is monitored by a probe 14 which is operable as follows: "STOP" switch off pump(s) 11, 12; "DUTY" switch on pump 11; "STANDBY" switch on pump 12; and "ALARM" trigger an alarm advising that Sboth pumps have failed or cannot control the fluid level 13.

The cleaning apparatus 20 has a telescopic support arm 21 pivotally mounted (for movement in a vertical plane) on a mounting block 22 fixed to the wall of the well. In normal operation, the arm 21 extends.

horizontally as shown, but it may be swung upwardly to move the cleaning system 20 adjacent the wall 15 for, eg. access to the pumps 11, 12.

A rotary union 23 is mounted at the distal end of the support arm 21 and has a fluid inlet fitting 24.

A hollow rotary shaft 25 is rotatably, sealably, journalled in the rotary union 23 and has two spray arms 26, 27 extending radially from a T-piece 28 at the lower end of the rotary shaft 25.. Spray pots 29, 30 are adjustably mounted at the distal ends of the spray arms 26, 27 and are. provided with respective spray-jet nozzles 31, 32 which spray the water in a fan-like o pattern in a band about the wall. 15 to a height above the "ALARM" level on the probe 14 and at or below the "STOP" level on the probe 14. The spray-jet nozzles 31, 15 32 are oppositely inclined in plan view to generate a rotational driving force for the spray arms 26, 27 of the rotor assembly 33.

A supply line 34, incorporating a reduced o pressure zone valve (not shown) is connected to a reticulated (mains) water supply and a solenoid valve f. controls the flow of water from the supply line 34 to the fluid inlet fitting 24 via flexible hose 36.

The operation of the cleaning system 20 will 0:00 now be described.

25 When the liquid level 13 reaches the "DUTY" level on the probe 14, primary pump 11 is switched on to pump sewage out of the well 10 until the fluid level falls to the "STOP" level on the probe 14, when the primary pump 11 is switched off. (If primary pump 11 fails, secondary pump 12 is switched on when the liquid level reaches the "STANDBY" level on the probe 14 and this pump will be switched off. when the liquid level-13 falls to the "STOP" level.) The solenoid valve 35 is connected to the control circuit (not shown) for the pumps 11, 12, 6 controlled by the probe 14.

When either pump 11, 12 is switched on, the solenoid valve 35 is opened to admit water (under mains pressure) to the cleaning system 20, and the water sprayed from the nozzles 31, 32 causes the rotor assembly 33 to rotate and washes the sewage residue from the wall 15 of the well 10 as the liquid level 13 falls.

When the pump(s) 11, 12 are switched off, the solenoid valve 35 is closed and the water supply is shut off.

*0Each time the well.10 is pumped to reduce the liquid level 13, the cleaning system 20 is operated to spray and wash the residue f rom the wall 15. As the residue is at least damp, it can be easily removed f rorn the wall In certain applications, where the water supply is limited or expensive, an. alternative embodiment of the cleaning system 20 may be installed, with thfa modifications shown in dashed lines in FIG 1.

A submersible pump 40 is located in the well below the "STOP" level and draws liquid f rom, the sewage in the well 10 via a filtration unit 41. The output of pump 4.0 is connected via a pipe or hose 42 to 25the hose 36 (the supply line 34 and solenoid valve omitted).

The submersible pump 40 is operated by the.

control. circuit when either pumps. 11 or 12 are operated to reduce the liquid level 13 in the well..

While there is a ready supply of liquid in the well, the f iltration unit 41 must remove any particles which could clog the spray-nozzle jets 31, 32.I To minimise the destructive offset of hydrogen sulphide (H.

2 S) fumes in the, well 10, fine mist spray nozzles (not shown) may be provided along the radial arms 26, 27 to provide a "curtain" of spray over the 7 sewage in the well.

As the residue is washed from the wall while still damp, there is nil (or minimal) build-up of the residue on the wall. In addition to avoiding the requirement for removal of the residue by manual means as in existing wells, the removal also results in increased life in the well fittings, eg. ladders, chains, pipes, etc.

For grease traps or tanks, detergent may be added to the water, and the water may be heated, to assist in removal of the (primarily fatty) residues.

o It will be readily apparent to the skilled 00: addressee that the installation costs of the cleaning °o system can be quickly recouped relative to the on-going 0'S 15 maintenance costs for existing wells.

oo Various changes and modifications may be made to the embodiments described and illustrated without departing from the present invention as defined in the 0o 0 appended claims.

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Claims

1. A cleaning system for wells (as hereinbefore defined) including: a support frame mountable on a wall of the well; a rotor assembly rotatably mounted on the support frame rotatable about an axis substantially parallel to the wall, or the vertical axis, of the well; a plurality of spray jet nozzles on the rotor assembly, directed towards the wall; supply means for directing liquid under pressure to the spray-jet nozzles; and means for rotating the rotor assembly; so arranged that as the rotor assembly is 0° 15 rotated, liquid sprayed from the spray jet nozzles washes residue or wastes down the wall.

2. A system as claimed in Claim 1 wherein: o the support frame includes at least one support arm hingedly mounted on the wall and movable 20 between an operational position and a retracted position, the arm supporting the rotor assembly substantially centrally of the well.

3. A system as claimed in Claim 2 wherein: o f the arm is telescopic. 25

4. A system as claimed in Claim 2 or Claim 3 wherein: the rotor assembly includes: a tubular rotary shaft sealably journalled in a rotary hub on the distal end of the support arm, 2- 30 the rotary hub having an inlet connectable to the supply means; at least two spray arms radiating from the rotary shaft; and spray-jet nozzles provided at or adjacent the distal ends of the spray arms to spray liquid onto A the wall.

U.C 0 I i i flb'- r: II, o u e 0 00 9 0 00 0 0i 0 00 0 0 04 0 0 1 0 o II LCa~i A system as claimed in Claim 4 wherein the rotor assembly further includes: fine misting spray nozzles along the spray arms to form a curtain of spray.

6. A system as claimed in Claim 4 wherein: the spray-jet nozzles are arranged to spray the liquid in a band about the wall which includes the rise and fall of the liquid level in the well.

7. A system as claimed in Claim 4 or Claim 6 wherein: the spray-jet nozzles are inclined in plan view to provide the means to rotate the rotor assembly.

8. A system as claimed in any one of Claims 1 to 7 wherein: the supply means for the liquid includes a reticulated water supply and a solenoid valve, the solenoid valve being operable to supply the liquid to the spray-jet nozzles when the pump(s) in the well are operated to lower the liquid level in the well from a first preset level to a second preset level.

9. A system as claimed in Claim 8 wherein: the water supply includes a reduced pressure zone valve.

10. A system as claimed in any one of Claims 1 to 9 wherein: the supply means for the liquid includes a pressure pump which draws liquid from waste in the well via filtratIon means, the pressure pump being operable when pump(s) in the well are operated to lower the liquid level in the well from a first preset level to a second preset level.

11. A system as claimed in Claim 10 wherein: the pressure pump is submersible.

12. A cleaning system for wells (as hereinbefore defined) substantially as hereinbefore described with reference to the accompanying drawings. ii

13. A well (as hereinbefore defined) incorporating the cleaning system as claimed in any one of Claims 1 to 12. DATED this twenty-sixth day of September

1994. DOUGLAS BRETT McCASKER, By his Patent Attorneys, GRANT ADAM'~S COMPANY. A 0 #000 0* JO C 00 0 0*0 0 A 0~. *0 C 0**0 0 04 0000 0044 4; 4 0 It C I C 4*04 CO U 4 00 0 04 i ABSTRACT A cleaning system (20) for a sewage well has a rotor assembly (33) rotatably mounted on a support arm (21) mounted on a wall (15) of the well Spray-jet nozzles (31, 32) spray water onto the wall when water is supplied to the cleaning system via a supply line (34) and solenoid valve The solenoid valve (35) is opened when pumps (11, 12) are switched on to lower the liquid level (13) to a "STOP" level measured by a probe The washing of the wall as the liquid level (13) falls prevents a build-up of residue on the wall 0 04 seaQ 00 0 04:. 6 0 S a 9 iI. *1I i I I