WELL CLEANING APPARATUS

Abstract

Systems, apparatus and methods are described that can be used for cleaning wells using unfiltered fluids and fluids that contain solid matter. Spray nozzles cooperate with deflectors to direct and outflow of the apparatus to surfaces to be cleaned. The apparatus comprises a mixer having an inner chamber, an inlet and a plurality of outlets. Deflectors are attached to associated outlets. The inner chamber has an impact surface located opposite the inlet, the impact surface redirecting the flow of fluid proportionately to the outlets and minimizes eddies in the flow of fluid. The deflectors generate a force from the fluid flow that includes rotational and/or translational components sufficient to cause rotation about a first axis and/or translation along a second axis.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

The present Application claims priority from U.S. Provisional Patent Application No. 61/167,851 filed Apr. 8, 2009, entitled “Improved Well Cleaning Apparatus,” which application is expressly incorporated by reference herein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to well cleaning equipment and more particularly to in-well cleaning apparatus.

2. Description of Related Art

Sewage systems are in wide spread use for the removal of liquid waste from houses, factories and agricultural sites. The sewage flows through pipes into intermediate wells and finally into treatment plants or waste dumps. Electric pumps are usually used to maintain the flow and keep the wells below maximum capacity. These pumps are configured to operate when the level in the wells reaches a preset limit indicating that the flow needs pumping.

When the well level falls to a minimum level the pump is switched off and this level may be maintained for some time leaving a biofilm residue on the walls of the well between the maximum and minimum levels. This residue tends to harden and build up thus reducing the capacity of the well, and increasing the frequency of the pump operation.

Wastewater collection and treatment systems are a source of bad odors, the most prevalent coming from Hydrogen Sulphide, a toxic and corrosive gas with a characteristic rotten-egg smell. This is a bacterially mediated process that occurs in the submerged portion of sanitary sewerage systems. It begins with the establishment of a slime layer below the water level, composed of bacteria and other inert solids held together by a biologically secreted protein “glue” or biofilm called zooglea. When this biofilm becomes thick enough to prevent the diffusion of dissolved oxygen, an anoxic zone develops under the surface.

Hydrogen Sulphide is also a precursor to the formation of Sulphuric Acid, which causes the destruction of metal and concrete substrates and appurtenances within wastewater facilities and collection stations. The effect of biogenic sulfide corrosion and the formation of a 7% Sulphuric Acid solution on concrete surfaces exposed to the sewer environment are devastating. Entire pump stations and manholes and large sections of collection interceptors have collapsed due to the loss of structural integrity in the concrete. Accordingly the residue must be cleaned off the well walls and removed from the surface of the sewer water periodically to maintain the system in good working order as well as protecting concrete structures against the biogenic sulfide corrosion in wastewater collection and treatment systems so as to met the structure's anticipated design life as well as protecting the surrounding ground level infrastructure and environment.

Obstructions of the nozzles in prior art systems present serious difficulties in the operation of well cleaning apparatus. Well cleaning equipment must be frequently removed for cleaning as solid materials build up on the inner surfaces of the nozzles. Nozzles must be cleaned and, in some instances cleaning devices must be disassembled for cleaning on a regular basis.

BRIEF SUMMARY OF THE INVENTION

Certain embodiments of the present invention comprise systems and methods for which overcome or at least significantly reduce problems relating to the cleaning of wells by prior art systems. In particular the present invention employs spray nozzles and a submerged pumping system which allows the apparatus to use the sewage in the well to clean the walls causing aeration of the introduced effluent, hydrating the grease, oils, fats that contribute to biofilm so that it can be easily transported, via the sewer system to treatment plant for treatment. Systems and apparatus according to certain aspects of the invention can use a liquid stream containing solid materials which prior art apparatus has not achieved. Apparatus may be provided at well openings, removing the need for confined space entry. In certain embodiments, apparatus can be easily repositioned from the well entry point to allow access to the well to facilitate maintenance.

Certain embodiments of the invention provide apparatus that comprises a mixer having an inner chamber, an inlet and a plurality of outlets and one or more deflectors attached to associated outlets. In some of these embodiments, each deflector directs a fluid received from its associated outlet to a surface within a well. In some of these embodiments, the mixer receives a pressurized, unfiltered flow of fluid at the inlet and splits the supply of fluid between the outlets.

In certain embodiments, the inner chamber includes an impact surface located opposite the inlet, the impact surface redirecting the flow of fluid proportionately to the outlets. In some of these embodiments, the impact surface is curved and has an apex opposite the inlet. In some of these embodiments, the radius of curvature is selected to minimize eddies in the flow of fluid. In some of these embodiments, the radius of curvature is selected to obtain uniformity of fluid pressure throughout the inner chamber. In some of these embodiments, the radius of curvature is selected to obtain a desired distribution of fluid pressure throughout the inner chamber.

In some of these embodiments, the deflectors generate a force from the fluid flow that includes rotational and/or translational components sufficient to cause rotation about a first axis and/or translation along a second axis. The first and second axes can be the same axis or related axes. In some of these embodiments, the magnitudes of the forces are controlled by an angle at which the deflector is attached to its associated outlet. In some of these embodiments, the magnitude of the force is controlled to obtain a speed of rotation of the apparatus. In some of these embodiments, the magnitude of the force is controlled using a spring. In some of these embodiments, the magnitude of the force is controlled using aerodynamic members attached to one of the deflectors. In some of these embodiments, the magnitude of the force is controlled using aerodynamic members attached to the mixer. In some of these embodiments, the magnitude of the force is controlled using hydrodynamic members attached to one of the deflectors. In some of these embodiments, the magnitude of the force is controlled using hydrodynamic members attached to one of the deflectors.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an elevation depicting an example of the presently claimed apparatus deployed within a well.

FIG. 2 shows a cross-sectional view of a mixer according to certain aspects of the invention.

FIG. 3 shows variously angled views of a deflector according to certain aspects of the invention.

FIG. 4 is a detailed view of a mixer.

FIG. 5 is a detailed view of a mixer.

DETAILED DESCRIPTION OF THE INVENTION

Embodiments of the present invention will now be described in detail with reference to the drawings, which are provided as illustrative examples so as to enable those skilled in the art to practice the invention. Notably, the figures and examples below are not meant to limit the scope of the present invention to a single embodiment, but other embodiments are possible by way of interchange of some or all of the described or illustrated elements. Wherever convenient, the same reference numbers will be used throughout the drawings to refer to same or like parts. Where certain elements of these embodiments can be partially or fully implemented using known components, only those portions of such known components that are necessary for an understanding of the present invention will be described, and detailed descriptions of other portions of such known components will be omitted so as not to obscure the invention. In the present specification, an embodiment showing a singular component should not be considered limiting; rather, the invention is intended to encompass other embodiments including a plurality of the same component, and vice-versa, unless explicitly stated otherwise herein. Moreover, applicants do not intend for any term in the specification or claims to be ascribed an uncommon or special meaning unless explicitly set forth as such. Further, the present invention encompasses present and future known equivalents to the components referred to herein by way of illustration.

Embodiments of the present invention can be deployed in well cleaning apparatus in order to improve the efficiency and effectiveness of such equipment. Wells may contain a body of fluid comprising waste materials or other solids, including, for example sewage, storm run-off, fluids collected from cleaning equipment, agricultural wastes and so on. For the purposes of this description, an example of well cleaning apparatus will be used that bears certain similarities to apparatus described in the application filed under the patent cooperation treaty and numbered PCT/AU2007/001083 (and incorporated by reference herein in its entirety). Certain embodiments of the present invention can be used to retrofit conventional well cleaning apparatus but it will be appreciated that certain components of well cleaning equipment may be adapted and/or reconfigured to maximize the advantages accrued from the present invention. In some embodiments, for example, pump operating characteristics may be loosened because spray assemblies according to certain aspects of the invention can disperse accretions of solids deposited during variations in pump output. PCT application No. PCT/AU2007/001083 is incorporated by reference herein in its entirety.

As depicted in FIG. 1, a well cleaning apparatus according to certain aspects of the invention can be mounted on, or suspended from a frame or bracket 11 typically attached by fasteners 12 at the top of well, tank, drum, vault or other container 10. For the purpose of description, the terms well, tank, drum, vault, sump or other container will be used henceforth interchangeably; “well 10” will be commonly used to describe any such container. Fluid is transmitted through a pipe or hose 17 to a conduit 14 and from there to spray assembly 15 which directs jets of fluid using deflectors 16 of spray assembly 15. In certain embodiments, spray assembly 15 is rotatably mounted to conduit 14 such that spray assembly 15 may rotate around axis of rotation 13 in order to obtain rotating water jets. Rotation is typically driven by force of water pressure. In operation, jets may provide a spray to the walls of the well 10, the surface of liquids 100 in the well 10 or tank and other equipment located within the well 10. The hose or pipe 17 is typically coupled to the conduit at coupling 18 and the fluid provided for cleaning can be obtained from an external source of water or derived from effluent pumped from the well by a submersible or other pump 19. It will be appreciated that, in conventional systems, pump 19, conduit 14, coupling 18 and jets may be subject to clogging, even where the system and its components are designed to pass anticipated solids such as, for example, solids up to 50 mm in diameter and 90 mm long found in a sewage stream.

Certain embodiments of the present invention provide a spray assembly 15 for use in an automatic well washer that can reduce and/or eliminate the occurrence of blockage from accumulation of solid matter in a fluid stream used to wash the well, vault or tank. Referring to FIGS. 2 and 3, a spray assembly according to certain aspects of the invention typically comprises a mixer 20 and one or more deflectors 30 that cooperate to direct a flow of fluid to spray to the walls of the well 10, the surface of liquid 19 in the well 10 and other equipment located within the well 10. Mixer 20 is configured to optimize, control and generate flows and currents that prevent buildup of solid materials in an interior chamber 22 of mixer 20 and on the deflectors 30. Deflectors 30 are typically used to direct the flow of fluid to a target area for cleaning and may be angled or tilted in a manner that causes the spray head to rotate.

The examples depicted are dimensioned according to the requirements of a sewage treatment application. The depicted devices can be scaled according to need, although it will be appreciated that the dimensions of certain elements may remain constant or be scaled to a lesser degree. In the example shown in FIG. 2, inlet 24 has a substantially cylindrical portion that has a diameter that is similar to, or the same as the diameter of corresponding substantially cylindrical portions of outlets 26 and 28. In the example, an inner diameter of the cylindrical portions is dimensioned as approximately 2.4 inches. In at least some embodiments, the inner surface of one or more of inlet 24 and outlets 26 and/or 28 may be threaded for attaching pipes, vanes, deflectors and the like. In the example, the axes of outlets 26 and 28 are each angled at approximately 43.75°. Impact surface 220 of chamber has curved surface that is typically elliptical, parabolic or circular in profile. As shown in the example of FIG. 2, a typical device for use in sewage treatment has a generally circular impact surface 220 having a radius of curvature of approximately 10.5 inches.

In conventional systems, eddy currents may create areas of low pressure within a spray head and variations in pressure may be observed during a pumping cycle, or when a flow fluid or liquid through the system and/or when a pump ceases operation. In response to such variations, conventional equipment may become progressively clogged as solids settle at junctions or distributors (e.g. in a tee piece), in small diameter pipe lines, fittings, bends, elbows, valves and areas of low pressure. Clogging can lead to partial or complete obstruction of the system. However, a mixing chamber constructed according to certain aspects of the invention avoids the potential for obstruction. For example, the curvature of impact surface 220 may be selected based on anticipated viscosity of treated fluids and characteristics of the solid materials contained therein.

Certain embodiments provide a spray assembly 15 that includes mixer 20 having specifically engineered curves calculated to provide clog free operation of washer head using un-filtered stream of sewer water, storm water or the like. The example of FIG. 2 shows one embodiment where dimensions are typical for use in many sewage applications. Radii of curvature, cross-sectional diameters and other dimensions are selected based on parameters attributable to the application, including range of viscosity of the fluid, maximum and minimum size of solids, pressure developed by pump 19 and operating temperatures. Fluid flowing into chamber 22 from inlet 24 is directed to outlets 26 and 28. An impact surface 220 defined generally opposite the inlet is constructed to minimize undesired reflections and resultant waves, eddies and vortices in the fluid. Thus, the fluid flows through chamber 22 relatively smoothly. In some embodiments, the fluid can be caused to swirl, rotate or be otherwise agitated as desired.

In particular, the structure, location and dimensions of certain curved sections are calculated to enable free flow of un-filtered liquids. Fluid entering a first orifice 24, which serves as an inlet, passes to interior chamber 22 where the flow splits and exits the interior chamber 22 through other orifices 26 and 28 that serve as outlets to vent the liquid. The shape and dimensions of interior chamber 22 are selected to cause deposits of solids and bio-solids to be rolled and circulated into the liquid passing through the interior chamber 22. Solids and bio-solids are then pushed by the liquid flow liquid out of outlets 26 and 28.

In certain embodiments, mixer 20 can cause liquid to flow around solids and otherwise apply pressure to solids which have previously settled within interior chamber 22, including settlements occurring due to end of a pump cycle or during periods of low fluid flow. The structure of interior chamber 22 can create an agitation that causes accumulated solids and/or bio-solids to be lifted and circulated and eventually carried through outlets 26 and 28.

FIG. 3 depicts various views of a deflector 30 that can be used in conjunction with spray assembly 15. One or more deflectors 30 can be attached to mixer 20. In certain embodiments, deflector 30 is designed to respond to hydrodynamic forces created by the liquid as it is expelled through outlets 46 and 48. As the fluid passes over surfaces of the deflector 30, it may exert direct pressure on the surfaces of deflector 30 and/or generate aerodynamic or hydrodynamic pressure differences that cause the desired rotation. Thus, the volume and pressure of the liquid forced out of the mixer 20 can be used to cause and control rotation of the spray assembly. Rotation typically occurs when deflector 30 is suitably angled with respect to the outflow from outlets 26 and 28 and with respect to an axis of rotation 13 of the spray assembly. Thus, deflector 30 may have a “park” angle at which deflector 30 causes no rotational motion.

In certain embodiments, speed of rotation can be controlled by configuration and position of deflectors 30. A desired speed of rotation can be selected in this manner. Typically the angle of deflector 30 relative to an axis of rotation 13 of the spray assembly is selected to control speed of rotation. Speed of rotation may be automatically controlled to limit rotation to the desired speed of rotation by varying the angle and position of deflectors based on current speed of rotation. In particular, angle and/or position of deflectors 30 may be automatically adjusted in response to changes in pressure and volume of liquid passing through the outlets 26 and 28 of mixer 20. Consequently, the disclosed system may accommodate a broad range of pumps 19 and modes of operation of those pumps 19. For example, the system may accommodate a pump 19 driven at different rates selected to obtain different throughputs.

In certain embodiments, a pre-tensioned spring system can be used to control angle and or position of deflectors 30 based on actual speed of rotation. Such control can reduce liquid dispersal to a “ribbon action” and can prevent aerosol action and/or misting that can cause release of H₂S and other undesired gas components. In some embodiments, speed of rotation may be automatically controlled using aerodynamic or hydrodynamic elements attached to the deflector and/or mixer 20, whereby the additional elements generate a force resistant to rotation proportional to the speed of rotation of spray assembly 15.

In certain embodiments, spray assembly 15 may be free to translate along the axis of rotation under the force of the outflow from outlets 26 and 28. Additional mechanisms may adjust the angle and direction of the deflector 30 after translation a predetermined distance, causing a reversal in direction and resulting in an oscillation of the spray assembly 15 that increases the area treated by the system. In certain embodiments the form, size and angle of the deflectors 30 can be used to control surface area of spray coverage.

The spray assembly 15 may be operated in applications where full-size solids are required to pass through freely without obstruction and clogging at various volumes and pressures. Full-size solids include solids that can pass through an inlet orifice having a predetermined diameter.

In certain embodiments, liquids containing solids and/or bio-solids passing through mixer 20 are typically agitated, oxygenated and homogenized. Moreover, a surface of a liquid contained by the well may be agitated, oxygenated and homogenized by the action of spray assembly 15. In addition to agitation, oxygenation and homogenization substances such as fat, oil, grease and bio-film present on the surface of the liquid in the well may be solubilized.

In certain embodiments, mixer 20 can be sized to accommodate other outflows without fixing a new mixing chamber by simply attaching flow reducers to outlet orifices.

FIGS. 4 and 5 are engineering drawings showing detailed design information associated with one example of a spray assembly 15 according to certain aspects of the invention.

Additional Descriptions of Certain Aspects of the Invention

The foregoing descriptions of the invention are intended to be illustrative and not limiting. For example, those skilled in the art will appreciate that the invention can be practiced with various combinations of the functionalities and capabilities described above, and can include fewer or additional components than described above. Certain additional aspects and features of the invention are further set forth below, and can be obtained using the functionalities and components described in more detail above, as will be appreciated by those skilled in the art after being taught by the present disclosure.

Certain embodiments of the invention provide a spray apparatus that may be used in cleaning wells. The apparatus typically comprises a mixer having an inner chamber, an inlet and a plurality of outlets and one or more deflectors attached to associated outlets. In some of these embodiments, each deflector directs a fluid received from its associated outlet to a surface within a well. In some of these embodiments, the mixer receives a pressurized, unfiltered flow of fluid at the inlet and splits the supply of fluid between the outlets.

In some of these embodiments, the inner chamber includes an impact surface located opposite the inlet, the impact surface redirecting the flow of fluid proportionately to the outlets. In some of these embodiments, the impact surface is curved and has an apex opposite the inlet. In some of these embodiments, the radius of curvature is selected to minimize eddies in the flow of fluid. In some of these embodiments, the radius of curvature is selected to obtain uniformity of fluid pressure throughout the inner chamber. In some of these embodiments, the radius of curvature is selected to obtain a desired distribution of fluid pressure throughout the inner chamber.

In some of these embodiments, the fluid includes solids. In some of these embodiments, the solids comprise bio-solids. In some of these embodiments, the desired distribution of fluid pressure is sufficient to dislodge solids accumulated solids in the inner chamber.

In some of these embodiments, wherein the deflectors generate a force from the fluid flow. In some of these embodiments, the force includes a rotational component sufficient to cause rotation of the apparatus. In some of these embodiments, the magnitude of the force is controlled by an angle at which the deflector is attached to its associated outlet. In some of these embodiments, the magnitude of the force is controlled to obtain a speed of rotation of the apparatus. In some of these embodiments, the magnitude of the force is controlled using a spring. In some of these embodiments, the magnitude of the force is controlled using aerodynamic members attached to one of the deflectors. In some of these embodiments, the magnitude of the force is controlled using aerodynamic members attached to the mixer. In some of these embodiments, the magnitude of the force is controlled using hydrodynamic members attached to one of the deflectors. In some of these embodiments, the magnitude of the force is controlled using hydrodynamic members attached to one of the deflectors.

In some of these embodiments, the force includes a translational component sufficient to translate the apparatus in a direction generally perpendicular fluid exiting the outlets. In some of these embodiments, the apparatus oscillates along the direction generally perpendicular fluid exiting the outlets.

Although the present invention has been described with reference to specific exemplary embodiments, it will be evident to one of ordinary skill in the art that various modifications and changes may be made to these embodiments without departing from the broader spirit and scope of the invention. Accordingly, the specification and drawings are to be regarded in an illustrative rather than a restrictive sense.

Claims

1. An apparatus, comprising:

a mixer having an inner chamber, an inlet and a plurality of outlets;

one or more deflectors, each deflector attached to an associated outlet, wherein

each deflector directs a fluid received from its associated outlet to a surface within a well and wherein

the mixer receives a pressurized, unfiltered flow of fluid at the inlet and splits the supply of fluid between the outlets.

2. The apparatus of claim 1, wherein the inner chamber includes an impact surface located opposite the inlet, the impact surface redirecting the flow of fluid proportionately to the outlets.

3. The apparatus of claim 2, wherein the impact surface is curved and has an apex opposite the inlet.

4. The apparatus of claim 3, wherein the radius of curvature is selected to minimize eddies in the flow of fluid.

5. The apparatus of claim 3, wherein the radius of curvature is selected to obtain uniformity of fluid pressure throughout the inner chamber.

6. The apparatus of claim 3, wherein the radius of curvature is selected to obtain a desired distribution of fluid pressure throughout the inner chamber.

7. The apparatus of claim 6, wherein the fluid includes solids.

8. The apparatus of claim 7, wherein the solids comprise bio-solids.

9. The apparatus of claim 7, wherein the desired distribution of fluid pressure is sufficient to dislodge solids accumulated solids in the inner chamber.

10. The apparatus of claim 1, wherein the deflectors generate a force from the fluid flow.

11. The apparatus of claim 10, wherein the force includes a rotational component sufficient to cause rotation of the apparatus.

12. The apparatus of claim 11, wherein the magnitude of the force is controlled by an angle at which the deflector is attached to its associated outlet.

13. The apparatus of claim 11, wherein the magnitude of the force is controlled to obtain a speed of rotation of the apparatus.

14. The apparatus of claim 11, wherein the magnitude of the force is controlled using a spring.

15. The apparatus of claim 11, wherein the magnitude of the force is controlled using aerodynamic members attached to one of the deflectors.

16. The apparatus of claim 11, wherein the magnitude of the force is controlled using aerodynamic members attached to the mixer.

17. The apparatus of claim 11, wherein the magnitude of the force is controlled using hydrodynamic members attached to one of the deflectors.

18. The apparatus of claim 11, wherein the magnitude of the force is controlled using hydrodynamic members attached to one of the deflectors.

19. The apparatus of claim 10, wherein the force includes a translational component sufficient to translate the apparatus in a direction generally perpendicular fluid exiting the outlets.

20. The apparatus of claim 19, wherein the apparatus oscillates along the direction generally perpendicular fluid exiting the outlets.