Sumped manholes are commonly used in sewer systems to temporarily collect settleable solids until they can be removed from the system during routine maintenance. As illustrated in
In a drain system 10 including a typical sumped manhole 12, fluids flow into sumped manhole 12 via inlet pipe 18 and out of sumped manhole 12 via outlet pipe 22, as generally indicated with arrows 28. The fluids moving from inlet pipe 18 to outlet pipe 22 carry solids, such as sediment and larger waste items, and drop at least a portion of the solids carried therewith into sump 26. The solids collected in sump 26 include sediment 32, which collects on bottom 16 of sumped manhole 12 for subsequent removal during periods with a low flow rate. During periods of high flow rates, the high energy flow jet substantially linearly extends between inlet pipe 18 and outlet pipe 22 introducing a circular flow pattern, as generally indicated by arrow 30 in
Until recently, the effectiveness of standard sumped manholes 12 at removing settleable solids has not been quantified, and was assumed to be marginal. Due to the assumed marginal removal efficiencies of standard sumped manholes 12, several products have been developed that claim to greatly improve the performance of sumped manholes 12 via the addition of internal components to sumped manhole 12. These products focus on designs that claim to increase removal efficiencies, reduce scour, or both.
One such product is a floatables skimmer 40 as illustrated, for example, in
Furthermore, some systems use internal components to swirl water, which increases particle travel paths, consequently resulting in increased removal efficiencies. While swirling low flows have proven to increase removal efficiencies, swirling flows also have the effect of creating vortices during high flows, greatly increasing scour in comparison to standard sumped manholes. Scour testing has revealed that scour in standard sumped manholes in product-modified systems is a more important factor than removal efficiency in determining a treatment devices typical annualized removal efficiency. Essentially, the removal efficiency of a structure is negated if it is not designed to retain previously settled solids during high flows.
Other storm water treatment systems configured to improve the performance of standard sumped manholes by focusing on scour suppression, such systems often utilize a horizontal false floor. While a false floor is relatively effective at suppressing scour by providing a boundary between previously settled solids and high flows, the false floors introduce negative side effects such as reducing sediment removal efficiencies by effectively reducing the water depth and creating an obstruction for routine inspection and maintenance. Use of false floors is generally restricted for use within circular manholes and such false floors are not retrofittable, thereby limiting the overall applicability of such false floors.
In view of the above-described issues with existing storm water systems, there is room for improvement of standard sumped manholes and modifying products currently on the market.
One aspect of the present invention relates to an energy dissipator for use in a sumped manhole and including a sheet member. The sheet member defines a downstream surface, an upstream surface opposite the downstream surface, and opposing side edges each extending between the downstream surface and the upstream surface. The sheet member includes a plurality of apertures. Each of the plurality of apertures extends through both the downstream surface and the upstream surface. The sheet member extends in an arcuate manner between the opposing side edges. The dissipator is configured to intercept fluid flow within the manhole to decrease energy and control flow dynamics within the manhole. Other apparatus, assemblies, systems and associated methods are also disclosed.
Embodiments of the invention will be described with respect to the figures, in which like reference numerals denote like elements, and in which:
In view of issues identified with prior art sumped manhole systems, the current invention provides settleable solids management systems and methods including an energy dissipator working alone or in tandem with a floatables skimming device to increase removal of solids and reduce the scour of settleable solids in sumped flow-through manholes. In one embodiment, the system according to one embodiment of the current invention includes an energy-dissipating device on one or more of the inlets to the sumped manhole. The energy-dissipating device, or dissipator, is configured for installation within the sumped flow-through manhole in an arcuate shape curving away from the inlet pipe. The dissipator includes a plurality of apertures therein distributed in a pattern selected to dissipate more energy at selected portions thereof. In one example, the dissipator is installed to taper back toward the sidewall of the sumped flow-through manhole toward a bottom of the dissipator. A dissipator according to the present invention increases head losses as well as solids removal efficiencies of the drain system incorporating the dissipator.
While the dissipator is used alone in a sumped flow-through manhole per embodiments of the present invention, in some embodiments, the dissipator is used in tandem with a floatables skimmer positioned near an outlet pipe of the sumped flow-through manhole. The dissipator provides similar benefits when used with a floatables skimmer as when used alone.
Systems and components thereof according to the present invention improve upon prior art technologies by providing systems and associated methods to suppress scour within a sumped flow-through manhole thereby increasing efficiencies in settleable solids removal as compared to standard sumped manholes and improving access for inspection and maintenance by utilizing vertically oriented components placed as close to the manhole sidewalls, and therefore, the corresponding inlet or outlet pipe, as possible. Components of the settleable solids management system according to the present invention may be used to retrofit existing standard sumped manholes of any size and shape or as part of a new sumped flow-through manhole assembly.
For example,
Each of inlet hole 20 and outlet hole 24 are positioned above a bottom 16 of sumped flow-through sumped manhole 12 in a manner creating a sump 26 therebelow. In one example, each of inlet pipe 18 and outlet pipe 22 is positioned a distance from a bottom of the catch basis that is equal to or greater than about one and a half times a smallest inside diameter DI or DO of the inlet pipe 18 and the outlet pipe 22, respectively. The respective inside diameters DI or DO of inlet pipe 18 and outlet pipe 22 are sized based on where sumped flow-through sumped manhole 12 will be used and associated characteristics thereof, such as expected average and peak flow-rates.
Dissipator 112 is configured for installation in an arcuate manner relative to inlet pipe 18 as illustrated in
In one embodiment, dissipator 112 is substantially rectangular defining opposing side edges 118, a top edge 120, and a bottom edge 122. Side edges 118 are substantially linear, and are of substantially equal total height. In one example, side edges 118 are substantially parallel while in other examples, side edges 118 at least slightly converge toward each other the closer side edges 118 are to bottom edge 122. While top and bottom edges 120 and 122 may be entirely linear, in one example, each of top edge 120 and bottom edge 122 angles upwardly to a center point 124 and 126, respectively.
Dissipator 112 decreases flow energy as a fluid flow comes in contact with upstream surface 114 of dissipator 112. However, since dissipator 112 is not designed to fully stop or redirect all of fluid flow, dissipator 112 includes a plurality of perforations or apertures 128 formed therethrough allowing at least a portion of fluid flow to pass through dissipator 112 via such apertures 128. In one example, each aperture of the plurality of apertures 128 is of a similar shape (e.g., are all circular, oval, etc.) and size to others of the plurality of apertures 128; while in other embodiments, the plurality of apertures 128 may include apertures of various shapes and/or sizes. In one instance, apertures 128 are substantially circular in shape without points and/or corners to more evenly distribute forces from fluid moving through and/or being blocked around each aperture 128, so as to reduce a concentration of forces that would be seen in square or otherwise shaped apertures and that may result in tearing or other excess wear of dissipator 112 in such areas. The plurality of apertures 128 are arranged in a staggered pattern, in one example, other than areas specifically configured to not include any of the plurality of apertures 128, as will be further described below.
Each aperture of the plurality of apertures 128 includes an aperture edge 130 or perimeter edge thereof defining the overall size and shape of each of the plurality of apertures 128. In one example, each aperture edge 130 is formed in the substantially planar material forming dissipator 112 with a beveled orientation as illustrated in the detailed, cross-sectional view of
In order to decrease energy of the fluid flow in an effective manner, in one example, the plurality of apertures 128 are arranged to define one or more of a center blocking area 132 and/or a side blocking area 134 that are each void of any of the plurality of apertures 128, but rather provide solid, continuous presentations of the material forming dissipator 112. According to one embodiment, and as illustrated in
In one example, center blocking area 132 has a consistent width along its entire height while. In another example, center blocking area 132 tapers inwardly as center blocking area 132 extends from near top edge 120 to near bottom edge 122 of dissipator 112. Center blocking area 132 with the tapered shape further promotes the dissipation of energy from related fluid flow by deflecting larger portions of the influent high energy flow jet increases, that is as fluid flow from inlet pipe 18 interacts with higher portions of dissipator 112.
In one example, dissipator 112 also defines side blocking areas 134 positioned on opposing sides of center blocking area 132. Side blocking areas 134 present substantially solid portions of dissipator 112 free from any of the plurality of apertures 128. Side blocking areas 134 are configured to be positioned within the inside diameter DI of inlet pipe 18 near, and, in one example, extending beyond, an inside perimeter of inlet pipe 18 to block fluid flow at right and left sides thereof as the fluid rushes from inlet pipe 18. Side blocking areas 134 are sized and shaped in any suitable manner, and in one embodiment, are each sized larger than any ones of the plurality of apertures 128. In one example, center blocking area 132 and side blocking areas 134 are both present and serve to block fluid flow at positions in each of four quadrants (that is, positions about 90° offset from each other) of the fluid flow path during high flow rates, that is of the inside diameter DI of inlet pipe 18. In one example, dissipator 112 is formed with a total open area of between about 20% and 40%, for example, between about 25% and 35%.
Dissipator 112 is sized at least in part based on the value of the inside diameter DI of inlet pipe 18 so dissipator 112 can be placed to at least partially intercept substantially all fluid flow from inlet pipe 18 even during periods having high flow rates. While dissipator 112 is generally larger than the inside diameter DI of inlet pipe 18, in one example, dissipator 112 has a height equal to at least about one and one half times the inside diameter DI of inlet pipe 18, and in another example, is equal to at least about two times the inside diameter DI of inlet pipe 18. An overall width of dissipator 112 is also generally at least partially based on the inside diameter DI of inlet pipe 18. In one example, a width of dissipator 112 is equal to at least about one and one half times the inside diameter DI of inlet pipe 18, and in another example, is equal to at least about two times the inside diameter DI of inlet pipe 18.
Dissipator 112 is installed in sumped manhole 12 in any suitable manner that generally couples opposing side edges 118 of dissipator 112 in a substantially vertical orientation in sumped manhole 12 on each of opposing sides of inlet pipe 18 resulting in a curved or bowed dissipator 112. In one example, angled brackets 140 are used on either side of dissipator 112 to facilitate coupling with sumped manhole 12, however, use of other installation fasteners and/or brackets are also contemplated. Each bracket 140 generally includes a first leg 142 and a second leg 144 angled relative to one another, for example, at an angle of about 90°. With first leg 142 defining an exterior surface 146 and an opposing interior surface 148, and second leg 144 defining an exterior surface 150, which intersects with exterior surface 146, and an opposing interior surface 152, which intersects with interior surface 148. Each of first and second legs 142 and 144 includes a plurality of apertures 154 to receive fasteners, such as fasteners 158 and 160 (see
In one example, dissipator 112 is installed into a sumped manhole 12 previously installed as part of a storm water treatment system 110 while, in other example, dissipator 112 is installed into a new sumped manhole 12 prior to installation of sumped manhole 12 as part of a storm water treatment system. According to one example, installation begins with installing brackets 140 as illustrated with additional references to
In one example, each bracket 140 is positioned on inside surface 156 of sumped manhole 12 at an equal, but opposite, distance from a center of inlet pipe 18 and secured thereto using anchors or other suitable fasteners 160. In one example, at least one fastener 160 is thread through an aperture 154 in second leg 144 of bracket 140 at each of top and bottoms halves of bracket 140. Additional fasteners 160 are generally used along the length of bracket 140. In one example, upon installation, each bracket 140 extends with a substantially vertical orientation within sumped manhole 12.
Once brackets 140 are positioned and coupled to sumped manhole 12, dissipator 112 is installed. More specifically, in one example, downstream surface 116 of dissipator 112 is placed to abut exterior surface 146 of first leg 142 of each bracket 140 along each of opposing side edges 118 of dissipator 112. Aligning dissipator 112 with brackets 140 includes aligning at least one of a top edge 120 and a bottom edge of dissipator with tops or bottoms of brackets 140, in one embodiment. Fasteners 158, such as screws, are inserted through each first leg 142 of brackets 140 and into dissipator 112. When so installed, dissipator 112 curves or bows outwardly away from inlet pipe 18 between opposing side edges 18 thereof in a substantially semi-cylindrical shape. Dissipator 112 is generally open at a top and a bottom thereof, e.g., to allow for trash in the fluid flow to fall to sump 26. In one example, a center line of dissipator 112 is positioned at least about one foot or one half of inside diameter DI of inlet pipe 18, whichever is greater, further into sumped manhole 12 than the end of inlet pipe 18 in sumped manhole 12. The space between inlet pipe 18 and dissipator 112 allows for easier cleaning of inlet pipe 18 from within sumped manhole 12. The curved installation of dissipator 112 allows dissipator 112 to be placed closer to inlet pipe 18, which, in turn, provides additional open area in sumped manhole 12 on a side of dissipator 112 opposite inlet pipe 18. The additional open area within sumped manhole 12 makes access to sump 26 easier during maintenance of sumped manhole 12.
Due to the convergence of side edges 118 of dissipator 112 as they near bottom edge 122 thereof (see
Dissipators 112 configured and installed as described herein have been shown to greatly decrease and nearly eliminate scour within sumped manholes 12. In one example, use of dissipator 112 was found to limit the sediment effluent concentration to about 10 mg/l to about 15 mg/l as compared to standard sumped manholes without dissipator 112, which have sediment effluent concentration levels between about 150 mg/l to about 600 mg/l. In this manner, use of dissipator 112 has been shown to decrease sediment effluent concentration by over 90%, for example, from between about 93% to about 98%.
While introduction of dissipator 112 alone introduces benefits in decreasing fluid flow energy, in one example, dissipator 112 is used within drain system 110 along with an optional floatables skimmer 170. One embodiment of skimmer 170 is illustrated with reference to
Skimmer 170 is coupled to inside surface 156 of sumped manhole 12 using an installation bracket 190, in one embodiment. Installation bracket 190 may be of any suitable size and shape, for example, similar to bracket 140. In the illustrated embodiment, installation bracket 190 generally includes a first leg 192 and a second leg 194 angled relative to first leg 192, for example, at an angle of about 90°. First leg 192 defines an exterior surface 196 and an opposing interior surface 198. In one example, instead of first leg 192 being provided in a general rectangular shape like bracket 140, first leg 192 includes a top segment 200, an intermediate segment 202, and a bottom segment 204. Intermediate segment 202 is generally rectangular and is narrow in width forming a free longitudinal edge 206 opposite second leg 194. Top segment 200 extends upwardly from intermediate segment 202 defining a free angled edge 208 thereof, angled outwardly away from free longitudinal edge 206 of intermediate segment 202, to free edge 210 adjacent a top of installation bracket 190. Bottom segment 204 extends from intermediate segment 202 in a manner substantially symmetrical with top segment 200 to define a free edge 212 angled outwardly away from second leg 194 to a free edge 214 adjacent a bottom of installation bracket 190.
Second leg 194 defines an exterior surface 220, which intersects with exterior surface 196, and an opposing interior surface 222, which intersects with interior surface 198. At least second leg 194, and, in one example, first leg 192, includes a plurality of apertures 224 to receive fasteners, such as fasteners 228 and 230 (see
During one example, installation of skimmer 170 begins with installing brackets 190, as illustrated with additional references to
In one example, brackets 190 are positioned to face inside surface 156 of sumped manhole 12 at equal distances one either side of pipe 22 as measured from a center of outlet pipe 22 and are secured thereto using anchors or other suitable fasteners 230. The equal distance from a center of outlet pipe 22 to one of brackets 190 is equal at least to inside diameter DO of outlet pipe 22, according to one example. In one embodiment, a rubber gasket 226 or other suitable water-sealing agent is placed between installation bracket 190 and inside surface 156 of sumped manhole 12 as illustrated in
Once brackets 190 are positioned and coupled to sumped manhole 12, skimmer 170 is installed. More specifically, in one example, upstream surface 172 of skimmer 170 is placed to face exterior surface 196 of first leg 192 of each installation bracket 190 along each of opposing side edges 176 of skimmer 170. Aligning skimmer 170 with brackets 190 includes aligning at least one of a top edge 178 and a bottom edge 180 of skimmer 170 with tops or bottoms of brackets 190, respectively, in one embodiment. Fasteners 228, such as screws, are inserted through each first leg 192 of brackets 190 and into skimmer 170. In one example, rubber gaskets 226 or other water-sealing agent(s) is applied between installation bracket 190 and skimmer 170 to promote watertight installation. When so installed, skimmer 170 curves outwardly away from outlet pipe 22 between opposing side edges 176 thereof, which are maintained adjacent inside surface 156 of sumped manhole. In one example, skimmer 170 is installed in a substantially semi-cylindrical shape that is open at a top and bottom thereof. In one example, skimmer 170 is positioned at least about ⅔ of inside diameter DO of outlet pipe 22 or about one foot, whichever is greater, from the end of outlet pipe 22 in sumped manhole 12.
Upon installation, the enlargement of top and bottom segments 200 and 204 adds rigidity to skimmer 170 holding it to extend initially linearly away from inside surface 156 of sumped manhole 12. This saves wear and tear on skimmer 170, e.g., due to forces of fluid turbulence, allowing skimmer 170 itself to be made of a less rigid material, which may allow skimmer 170 to be rolled to a small size for storage, transport, and/or lowering into sumped manhole 12. In one example, a strengthening bracket 240 is used to further add to the rigidity of skimmer 170 as illustrated in
Strengthening bracket 240 is coupled to skimmer 170 on an opposite side of skimmer 170, which is facing the downstream surface 174, as compared to installation bracket 190. External surface 246 of strengthening bracket 240 faces upstream and is placed near, but not adjacent to, opposing side edges 176 of skimmer 170. And is coupled to skimmer 170 via screws or other suitable fasteners 256 extending through skimmer 170. In this manner, second leg 244 of strengthening bracket 240 extends downstream from skimmer 170 to interface with inside surface 156 of sumped manhole 12 and/or outside surface of outlet pipe 22, thereby adding additional rigidity to skimmer 170 to reduce deformation thereof even when upstream surface 172 of skimmer 170 is being hit with fluids and face turbulence in heavy flow rates. In one embodiment, strengthening bracket 240 is eliminated and/or all of skimmer 170 is eliminated from drain system 110. In one example, dissipator 112 alone or dissipator 112 in combination with skimmer 170 define a settleable solids management system according to the present invention.
Other embodiments of drain system 110 are also contemplated. For example, other drain systems 110A and 110B, according to the present invention, are shown in
The example arrangements of
Although the invention has been described with respect to particular embodiments, such embodiments are meant for the purposes of illustrating examples only and should not be considered to limit the invention or the application and uses of the invention. Various alternatives, modifications, and changes will be apparent to those of ordinary skill in the art upon reading this application. Furthermore, there is no intention to be bound by any theory presented in the preceding background of the invention or the above detailed description.
This application is a non-provisional application of and claims priority to U.S. Provisional Patent Application No. 62/006,430, filed Jun. 2, 2014, which is incorporated herein by reference.
Number | Date | Country | |
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62006430 | Jun 2014 | US |