System and method for preventing organism growth and other biological and physical fouling processes in pipes

Abstract

An apparatus and method for preventing fouling of an inside surface of a pipe wall wherein the apparatus comprises a fluid conduit extending along the pipe in communication with a fluid source having a quantity of an injection fluid therein and at least one inlet passage extending through the pipe wall from the fluid conduit positioned to inject a quantity of a fluid from the fluid source into the pipe in proximity to the interior surface of the pipe wall. The method comprises conveying the injection fluid from a fluid source to the pipe and injecting, under a pressure greater than the pressure within the pipe the injection fluid into the pipe through at least one inlet passage extending through the pipe wall from the fluid conduit, in proximity to the interior surface of the pipe wall.

Description

[0001] SYSTEM AND METHOD FOR PREVENTING ORGANISM GROWTH AND OTHER BIOLOGICAL AND PHYSICAL FOULING PROCESSES IN PIPES

[0002] BACKGROUND

[0003] 1. Technical Field

[0004] This disclosure relates generally to water pipes and in particular to a method and system for preventing adhesion from biological or physical processes in pipes such as the growth of organisms or frazil ice formation.

[0005] 2. Description of Related Art

[0006] Many utilities and processes require the introduction of a fresh water source such as municipal water supplies or cooling for a variety of industrial processes. One common method of providing such fresh water is to draw or otherwise pump such water from a lake, river or the like. A difficulty with such intake of natural or otherwise freestanding water sources is the potential to introduce organisms thereinto which may be prone to adhesion upon the interior surface of the pipe. Such organisms may be known to grow or otherwise multiple thereby reducing the water flow capacity of the pipe.

[0007] In particular, the prevalence of biofouling problems, including zebra and quagga mussels, and physical fouling, including frazil ice, presents significant challenges in maintaining the efficiency and functionality of water systems. These biofouling and physical fouling agents adhere to internal surfaces, reducing flow, increasing maintenance costs, posing blockage risks, and compromising water quality.

[0008] SUMMARY OF THE DISCLOSURE

[0009] According to a first embodiment of the present disclosure is an apparatus for preventing fouling of an inside surface of a pipe wall comprising a fluid conduit extending along the pipe in communication with a fluid source having a quantity of an injection fluid therein and at least one inlet passage extending through the pipe wall from the fluid conduit positioned to inject a quantity of a fluid from the fluid source into the pipe in proximity to the interior surface of the pipe wall. The apparatus may further comprise a pump configured to transport the injection fluid from the fluid source to the at least one inlet under pressure. The pump may be sized to transmit a quantity of the injection fluid at an injection pressure greater than the pressure within the pipe. The injection pressure is selected to create a flow of injection fluid within the pipe adjacent to the pipe wall at a predetermined velocity.

[0010] The at least one inlet passage may comprise a plurality of inlet passages. The plurality of inlet passages may be distributed radially around the pipe interior. The plurality of inlet passage may be distributed lengthwise along a length of the pipe. The plurality of inlet passages may be oriented to introduce the injection fluid to the interior of the pipe along the interior of the pipe wall. The plurality of inlet passages may be oriented to produce a helical flow of injection fluid along the interior surface thereof.

[0011] Each of the at least one inlet passage may define an injection fluid path therethrough. The injection fluid path may extend at a first angle between radial and tangential to the interior surface of the pipe wall. The injection fluid path may extend at a second angle to a transverse plane of the pipe. The at least one inlet passage may comprise a slot. The slot extends along an angle relative to a central axis of the pipe.

[0012] The injection fluid may be selected to be the same as a fluid conveyed through the pipe. The fluid source may comprise the fluid source for the pipe. The apparatus may further comprise an outlet extending through the pipe at a location downstream of the at least one outlet in fluidic communication with the fluid conduit. The fluid conduit may extend along the pipe for a treatment length thereof. The fluid conduit may surround the pipe along the treatment length.

[0013] According to a first embodiment of the present disclosure is a method for preventing fouling of an inside surface of a pipe wall comprising conveying an injection fluid from a fluid source to the pipe and injecting, under a pressure greater than the pressure within the pipe the injection fluid into the pipe through at least one inlet passage extending through the pipe wall from the fluid conduit, in proximity to the interior surface of the pipe wall.

[0014] Other aspects and features of the present disclosure will become apparent to those ordinarily skilled in the art upon review of the following description of specific embodiments in conjunction with the accompanying figures.

[0015] BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings constitute part of the disclosure. Each drawing illustrates exemplary aspects wherein similar characters of reference denote corresponding parts in each view,

[0017] Figure 1 is a perspective view of a system for preventing pipe fouling according to a first embodiment of the present disclosure.

[0018] Figure 2 is a cross sectional view of the system of Figure 1 as taken lengthwise along the pipe.

[0019] Figure 3 is a detailed view of the outlet of the system of Figure 1.

[0020] Figure 4 is a detailed view of the orifice of the system of Figure 1.

[0021] Figure 5 is a detailed view of the orifice of Figure 1 according to a further embodiment of the present disclosure.

[0022] Figure 6 is a cross sectional view of the pipe outlets as taken lengthwise along the pipe.

[0023] Figure 7 is a cross sectional view of the pipe outlets as taken across the pipe.

[0024] Figure 8 is a perspective view of a system for preventing pipe fouling according to a further embodiment of the present disclosure.

[0025] Figure 9 is a side cross sectional view of one of the collars of the system of Figure 8.

[0026] Figure 10 is a perspective sectional view a pipe segment for use in a system for preventing pipe fouling according to a further embodiment of the present disclosure.

[0027] Figure 11 is a cross sectional view of the pipe segment of Figure 10.

[0028] Figure 12 is a side view of the inside surface of the pipe of Figure 10 showing one of the outlet orifices. DETAILED DESCRIPTION

[0029] Referring to Figure 1 , an exemplary system for preventing fouling of pipes is illustrated generally at 10. The system 10 comprises a pipe 12 located within or to a water source 8. The pipe 8 extends to a water treatment plant 6, by way of non-limiting example although it will be appreciated that the present system may also be used with any other process or installation as well. The system includes a water outlet 20 extending from the pipe 8, one or more water inlets 30 extending into the pipe at a location upstream of the outlet and a pump adapted to convey water from the outlet to the inlet at a desired volumetric rate.

[0030] Turning now to Figure 2, the pipe 8 may be selected to be any size and / or type of fluid conveying pipe and may be formed of any material as are commonly used for such water pipes. The pipe 8 extends to a distal end 14 wherein water is drawn into the pipe 8 at the distal end. As illustrated the distal end is shown as having an open end of the pipe although it will be appreciated that any other apparatus may be provided at the distal end 14 as well including filters, screens or the like. The distal end may also extend to another structure or process such as a reservoir or the like. The pipe 8 includes an interior surface 16 so as to define an interior passage 18 therethrough.

[0031] The water outlet 20 comprises a fluid passage extending from the interior passage 18 of the pipe 8. The water outlet 20 includes an interior passage 22 in fluidic communication with the interior passage 18 of the pipe 8. Similarly, the water inlet 30 comprises a fluid passage extending to the interior passage 18 of the pipe 8. Although a single water inlet 30 is illustrated in Figure 2, more than one water inlet 30 may be utilized so as to introduce the pumped water at more than one location as will be further set out below. Similarly, more than one water outlet 20 may also be utilized so as to distribute location of the water drawn from the pipe. A transfer pipe 40 extends between the water outlet 20 and the water inlet 30 with a pump 50 therein. The pump 50 along with the inlet, outlet and transfer pipes are sized so as to transmit a quantity of water from a downstream located in the pipe 8 generally indicated at 24 to an upstream location generally indicated at 34 so as to form a secondary flow region, generally indicated at 60 around the pipe interior surface between the upstream and downstream locations. In particular, the volume of water passing through the system 10 may be selected such that the water exiting the water inlet 30 is adapted to flow at a velocity relative to the interior surface 16 of the pipe 12 greater than a predetermined speed. In particular for some organisms such as zebra mussels, it is known that larvae of such mussels can attach to a surface when the relative velocity between the water and the surface is less than 2 m / s. It will therefore be appreciated that the pump is selected to ensure that the water flowing through the secondary region 60 is great than 2 m / s relative to the interior surface 18 regardless of the velocity of the water flowing through a primary flow region 62. It will be appreciated that the primary flow region 62 will comprise the volume of water that is desired to flow through the pipe to the treatment plant 6 or the like by flowing past the water outlet wherein the water in the secondary flow region will be collected by the water outlet 20 for passing through the pump to the water inlet(s) 30.

[0032] Turning now to figure 3, an exit of the water inlet 30 is illustrated with an inlet orifice at the interior surface 16 of the water pipe 8. As illustrated in Figure 3, the orifice 70 may be adapted to discharge water into the interior of the pipe along the interior surface along a discharge path generally indicated at 72. As illustrated in Figure 3, the discharge path 72 may be substantially along the interior surface 16 in opposed directions with a spread angle generally indicated at 74 therebetween. The discharge angle may be selected to be any angle between 0 and 180 degrees. It will be appreciated that the discharge paths 72 may be arranged to be upstream or downstream in the pipe or may also be arranged to extend around a circumference of the interior surface 16 as illustrated in Figure 7. Combinations of these directions may also be utilized so as to discharge from the orifice in any desired direction including around a 360 degree arc around the water inlet 30. Optionally, as illustrated in Figures 4 and 5, the orifice may be oriented substantially perpendicular to the interior surface 16 or at an angle relative thereto. The orifice 70 may be selected to be of any desired shape so as to direct the discharge path 72 in the desired direction to form the secondary flow region 60. In particular as illustrated in Figure 6, the orifices 70 may be arranged along a length of the pipe each from a water inlet 30 as set out above. In particular, the orifices may be arranged to be slots as shown in Figure 7 with a width and length. It will be appreciated that other shapes may be useful as well including circular, or irregular. The slots may be arranged in uniformly spacing or otherwise as determined for that location. It will be appreciated that the water inlets 30 may be arranged in a longitudinal length along the pipe 8 at a single radial location or arranged radially around the pipe so as to provide multiple water introduction locations.

[0033] Turning now to Figures 8 and 9, according to a further embodiment the water inlets 30 may be formed as a ring injector 100 adapted to be located within the pipe interior 18 adjacent to the interior surface 16. In particular, the ring injector 100 may be in fluidic communication with the pump 50 through the transfer pipe 40 and may include one or more outlet orifices 102 directed one or more of upstream or downstream along the interior surface 16 of the pipe. The orifices 102 provide a discharge path 110 along the interior surface as set out above and may optionally include an angle relative to the interior surface as set out above. As shown in Figure 8, the system may include a plurality of ring injectors 100 arranged in series within the pipe interior.

[0034] As set out above, the present system provides an increased flow velocity adjacent to the walls of the pipe to prevent adhesion of organism or the like. It will be appreciated that although the present system utilizes a portion of the water already flowing through eh pipe from the water inlet for this purpose an external or other source for such water injection may also be provided. Other methods of increasing the size, volume or speed of the boundary layer along the pipe wall surface may also be utilized. Advantageously, by providing such a boundary layer, the instantaneous velocity of the water adjacent to the pipe wall may be independent of the actual volume passing through the pipe.

[0035] Turning now to Figure 10, a further embodiment of the present disclosure is shown of a system for preventing fouling of a water intake pipe 12 generally at 200. The system 200 includes a fluid conduit 202 surrounding a treatment length 204 of the pipe 12 and has at least one inlet passage extending through the pipe 12 within the treatment length 204. As illustrated the system may also include a length of supply conduit 206 extending to a fluid source 208. The fluid source may comprise an external storage containing a quantity of water, with or without additives to assist with cleaning and preventing fouling of the pipe interior. It will be appreciated that the fluid source may also comprise a location within the water intake or pipe 12 so as to draw water from the water intake for the treatment plant 6 or may optionally comprise the body of water 8 as well. In particular, any source of water or a different fluid may be used.

[0036] Turning now to Figure 11 , a cross section of the pipe 12 and surrounding fluid conduit 202 is shown as taken along a transverse cross-sectional view thereof. As shown in Figure 11 , the fluid conduit 202 and pipe 12 may form an annular passage 210 therebetween wherein the pipe 12 may have a plurality of injection passages 220 extending therethrough so as to permit water within the annular passage 210 to be injected into the interior 18 of the pipe 12. In particular each passage 220 defines an injection flow direction 222 along which the waterflows. As shown in Figure 11 , the injection flow direction may be oriented at an angle, generally indicated at 224 from normal, generally indicated at 226, to the interior surface 16 of the pipe 12. As illustrated in Figure 11 , the injection flow direction 222 is shown along a center of the path of flow. It will be appreciated that the path of fluid injected from the inlet passage may diverge or spread across a range of angles so as to form a fan or diverging flow as desired by a user.

[0037] As shown in Figure 12 for a single inlet passage 220 only, each of the at least one inlet passages 220 may be formed of a slot 230 extending along a length 232. The slot 230 may be angled relative to a central axis 13 of the pipe 12 by a second angle, generally indicated at 234. It will be appreciated that angling the slot 230 will result in angling of the injection path 222 relative to a transverse plane 15 of the pipe by an equal second angle 234. Thes second angle 234 may be any angle depending on the shape of the inlet passage to produce the desired flow around the interior surface 16 of the pipe. It will be appreciated that the combination of the first and second angles 224 and 234 for each injection path will form a helical flow of water around the interior surface 16 of the pipe. In particular, the injection path from the at least one inlet passage 220 will form a secondary flow region 60, as shown in Figure 2, around the interior surface 16 of the pipe. The secondary flow region 60 may form a boundary flow region proximate to the interior surface of the pipe at a higher flow velocity so as to form a higher surface shear speed at the interior surface 16 thereby preventing attachment of organisms or the like. The speed of such helical flow can be selected to be above a speed at which fouling or organism attachment may occur depending on the organism or substance desired to be controlled. In particular, the size of each injection passage 220 in combination with the sizing of the pump supplying water to the injection passages may be selected to produce the required flow rates, volumes and velocities for such water surface speed. It will be appreciated that the sizing, quantity and location of such inlet passages 220 may be selected and sized in any known manner. Each of the inlet passage 220 may be a common size or may be adjusted at different locations along the treatment length 204. It will also be appreciated that the sizes and angles for each of the inlet passages 220 may be varied along the treatment length to adjust the flow speed, rate and velocity within the secondary flow region 60.

[0038] Other shapes of inlet passages may also be used wherein the injection path 222 is oriented to have a first and second angle to form a similar helical flow around the interior surface 16 of the pipe 12. It will be appreciated that any of the injection passage disclosed herein may be used with any of the fluid conduit or system layout embodiments disclosed herein. While specific embodiments have been described and illustrated, such embodiments should be considered illustrative only and not as limiting the disclosure as construed in accordance with the accompanying claims.

Claims

What is claimed is:

1. An apparatus for preventing fouling of an inside surface of a pipe wall comprising: a fluid conduit extending along the pipe in communication with a fluid source having a quantity of an injection fluid therein; and at least one inlet passage extending through the pipe wall from the fluid conduit positioned to inject a quantity of a fluid from the fluid source into the pipe in proximity to the interior surface of the pipe wall.

2. The apparatus of claim 1 further comprising a pump configured to transport the injection fluid from the fluid source to the at least one inlet under pressure.

3. The apparatus of claim 2 wherein the pump is sized to transmit a quantity of the injection fluid at an injection pressure greater than the pressure within the Pipe.

4. The apparatus of claim 1 wherein the injection pressure is selected to create a flow of injection fluid within the pipe adjacent to the pipe wall at a predetermined velocity.

5. The apparatus of claim 1 wherein the at least one inlet passage comprises a plurality of inlet passages.

6. The apparatus of claim 5 wherein the plurality of inlet passages are distributed radially around the pipe interior.

7. The apparatus of claim 5 wherein the plurality of inlet passage are distributed lengthwise along a length of the pipe.

8. The apparatus of claim 5 wherein the plurality of inlet passages are oriented to introduce the injection fluid to the interior of the pipe along the interior of the pipe wall.

9. The apparatus of claim 8 wherein the plurality of inlet passages are oriented to produce a helical flow of injection fluid along the interior surface thereof.

10. The apparatus of claim 5 wherein each of the at least one inlet passage defines an injection fluid path therethrough.

11. The apparatus of claim 10 wherein the injection fluid path extends at a first angle between radial and tangential to the interior surface of the pipe wall12. The apparatus of claim 10 wherein the injection fluid path extends at a second angle to a transverse plane of the pipe.

13. The apparatus of claim 1 wherein the at least one inlet passage comprises a slot.

14. The apparatus of claim 13 wherein the slot extends along an angle relative to a central axis of the pipe.

15. The apparatus of claim 1 wherein the injection fluid is selected to be the same as a fluid conveyed through the pipe.

16. The apparatus of claim 15 wherein the fluid source comprises the fluid source for the pipe.

17. The apparatus of claim 1 further comprising an outlet extending through the pipe at a location downstream of the at least one outlet in fluidic communication with the fluid conduit.

18. The apparatus of claim 1 wherein the fluid conduit extends along the pipe for a treatment length thereof19. The apparatus of claim 18 wherein the fluid conduit surrounds the pipe along the treatment length.

20. A method for preventing fouling of an inside surface of a pipe wall comprising: conveying an injection fluid from a fluid source to the pipe; and injecting, under a pressure greater than the pressure within the pipe the injection fluid into the pipe through at least one inlet passage extending through the pipe wall from the fluid conduit, in proximity to the interior surface of the pipe wall.

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