LAUNDER COVER FOR USE IN A CLARIFIER TANK

Abstract: A cover apparatus for inhibiting the growth of algae on the fluid-contacting surfaces of a water treatment tank including a central effluent, a substantially vertical peripheral wall, a peripheral baffle, a substantially vertical weir (W), a spillway (S) and a launder channel (C). The cover apparatus includes at least one panel member (14) positionable over at least a portion of the launder channel to prevent light from reaching the interior surfaces thereof. In a preferred embodiment, a plurality of panel members cover substantially the entire launder channel, with each panel member comprising a substantially opaque material and spanning the width of the launder channel.

Description: LAUNDER COVER FOR USE IN A CLARIFIER TANK FIELD OF THE INVENTION The present invention relates generally to the cleaning of sewage treatment facilities and more particularly, to a cover system which inhibits the growth of algae on the surfaces of sedimentation water treatment tanks employed in such facilities. 1 SUBSTITUTE SHEET (fHJLE 26) 1 2 BACKGROUND OF THE INVENTION 3 4 The necessity for providing sewage treatment plants to clean and purify water 5 discharged from homes and factories is well known. The function of a sewage treatment 6 facility is to receive raw sewage (water containing waste material) as discharged from a city 7 sewage system and clean it to ultimately produce purified water. This is accomplished through θ a series of biological and mechanical processes. _ In a typical water treatment facility, the raw sewage is received from the sewage 10 system and passed through a coarse screen to remove large pieces of matter. The sewage is 11 next directed to one or more primary sedimentation tanks or clarifiers. The sewage remains 12 in primary sedimentation for a period of time sufficient to allow the majority of the heavy 13 matter to settle to the bottom of the tank forming sludge. This sludge is removed for 14 "digestion" by microorganisms. The digested sludge is then dried and can be used as compost 15 or fertiliaZer. The remaining liquid is treated in a second biological system to remove 16 ammonia. The liquid from this treatment is then aerated and passed into final sedimentation m. 7 water treatment tanks to remove any remaining solid material. 18 Water treatment tank configurations vary with each treatment facility 19 application. This notwithstanding, most final sedimentation water treatment tanks are circular. 20 This simplifies automatic skimming, churning and/or bottom scraping operations. More 21 specifically, by eliminating inaccessible corners and providing uniform surfaces, a revolving 22 scraper arm or skimmer blade can provide complete and efficient churning and prevent sludge 23 buildup. During operation of one type of water treatment tank, water containing sediment enters the center of the tank. In a continuous process, the lighter clean water is effectively decanted from the heavier sediment containing water. More particularly, the clean water is displaced from the tank by the constant flow of water containing sediment into the tank. The displaced clean water is forced to flow under a baffle plate for collecting floating scum and then over a weir, ultimately entering a clean water flow channel. The clean water flow channel directs the water to the next treatment stage where it is chlorinated and further made safe to be discharged into a river or stream. Presently, algae growth in the trough or launder channel is a serious problem in clarifier tanks. Specifically, as algae builds up on the weirs of the clarifier tank, it can substantially interfere with the hydraulic flow therethrough. Algae typically adheres to the surfaces of the weir and the trough, where it becomes unsightly and odorous. When the launder is cleaned, however, the algae is often loosened and causes clogging of the downstream filters. For many years, the removing of algae from the baffle, weir, spillway and clean water flow channel has been completed primarily by scrubbing the tank structure with brushes manipulated by hand. Because the final treatment tanks are quite large, this is a labor-intensive and tedious process , involving a large expenditure of man-hours . Additionally , the algae removing process must be done frequently, thereby further adding to the cost. More recent proposals directed at the problem of algae growth have utilized mechanical brushes to automate the cleaning process. One such device is disclosed in U.S. Pat. 4,830,748. While this apparatus is somewhat effective in cleaning the baffle, weir, spillway and clean water flow channel of a circular tank, it is somewhat limited in application in that it is adapted to be mounted to a revolving skimmer blade. Accordingly, it can only be effectively utilized with circular water treatment tanks incorporating such a blade. The cost of obtaining, installing, and maintaining such an automated system, though perhaps preferable to the alternative of periodic manual scrubbing, is also quite high. Other waste water facilities have utilized chlorine and other chemicals in sufficient concentrations to kill the algae. However, a large number of waste water facilities utilize a denitrification process that precludes the use of such chemical additives. As such, a need is recognized for a proactive system that inhibits the growth of algae in the launder channel of a clarifier tank. SUMMARY OF THE INVENTION It is, therefore, an object of the present invention to provide a cover system which is positionable over selected portions of the clarifier tank to prevent sunlight from reaching the surfaces of the launder channel. By blocking the sunlight, the cover system of the present invention inhibits the growth of algae on the surfaces of the launder channel and obviates the need for frequent scrubbing or complex automated cleaning devices. The inventive cover system comprises at least one panel member positionable above the channel, weir, and sometimes partially over scum baffle of a clarifier tank to prevent sunlight from reaching the surfaces thereof. In accordance with an illustrative embodiment of the present invention intended for use with a circular clarifier tank, one or more panel members having an outer radius of curvature corresponding to the radius of curvature of the tank may be employed so that the outer edge of the panel member or members may be arranged in a contiguous fashion along the inwardly facing wall of the tank and secured thereto at selected intervals. Where a plurality of panel members are employed, they may be mounted in an end to end abutting fashion such that the lateral side of each cover abuts a lateral side of an adjacent cover. In this manner, the panel members may be arranged over an entire launder channel to substantially prevent light from reaching the interior surfaces thereof. The cover system of the present invention has application to other tank configurations, such, for example, as those possessing a rectangular cross section. Referring to the mounting of the panel member in an end to end abutting fashion, the adjacent-abutting panel members form a smoothly-continuous surface by virtue of a shiplap-type joint through which each panel member are interconnected . This shiplap-type joint allows for the first lateral side of the panel member to be secured to the next adjacent one of said plural panel members so that together they form the smoothly -continuous surface. A method for inhibiting the growth of algae on fluid contacting surfaces of a water treatment tank is also provided. Typically, water treatment tanks include a central influent, at least one substantially vertical peripheral wall having an upper and interior surface, a peripheral baffle having inside and outside surfaces, a substantially vertical weir, a spillway, and a launder channel having a width. The method of inhibiting the growth of algae includes the step of securing to the peripheral tank wall, a first panel member positionable over at least a portion of the launder channel, for preventing light from reaching interior surfaces thereof. The first panel member is dimensioned and arranged to span the width of said launder channel and is comprised of a substantially opaque material. Thereafter, a second panel member is secured to the peripheral tank wall, the second panel member being positionable over at least a portion of the launder channel, for preventing light from reaching interior surfaces thereof. Similar to the first panel member, the second panel member is dimensioned and arranged to span the width of the launder channel and is comprised of a substantially opaque material. The second panel member is secured in end-to-end immediately-adjacent relation to said first panel member. Other objects and features of the present invention will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. BRIEF DESCRIPTION OP THE DRAWINGS In the drawings, wherein like reference numbers denote similar elements throughout the several views: FIG. 1 is a cutaway sectional view of a clarifier tank showing a cover panel member constructed in accordance with an illustrative embodiment of the present invention positioned thereon; FIG. 2 is a partial perspective view depicting an arrangement of cover panel members along the perimeter of a generally arcuate clarifier tank in accordance with the embodiment of FIG. 1; FIG. 3 is a perspective view of the cover panel member of FIG. 1; FIG. 4 is a cross sectional side view of a cover panel member constructed in accordance with another embodiment of the present invention and installed over a launder channel; FIG. 5 is a cross sectional side view of the cover panel member of FIG. 4 shown installed at a downwardly sloping incline; FIG. 6 is a cross sectional side view of the cover member of FIG. 4 shown installed at a downwardly sloping incline utilizing a modified support structure; FIG. 7 is a cross-sectional view of a cover member configured for installation over a dual- eir launder channel in accordance with a further embodiment of the present invention; and FIG. 8 is a cross-sectional view of a cover member configured in accordance with a further illustrative embodiment of the present invention positioned thereon; FIG. 9 A is a perspective view of a molded mounting flange having a radius of curvature substantially equal to the peripheral tank wall; FIG. 9B is a perspective view of a plurality of resilient clips which act to secure each cover over the channel; and FIG. 10 is a side view of a clarifier tank showing a cover panel member constructed in accordance with an illustrative embodiment of the present invention positioned thereon; and FIG. 11 is a perspective view of the cover panel as shown in FIG. 10. DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS Reference is now made to FIG. 1 showing the cover system 10 of the present invention installed over the clean water flow or launder channel C of a final sedimentation water treatment tank 12. In the illustrative embodiment depicted in FIG. 1, system 10 is configured as a modular assembly of individual panel members 14, only one of which panel members is shown. In accordance with the present invention, each panel member 14 is securable to tank 12 and, when installed in the position shown in FIG. 1, is dimensioned to completely cover the launder channel C, the spillway S, the weir gate W, and scum baffle B. As discussed previously, a principal object of the present invention is to prevent the gr< th of algae on the interior surfaces of the launder channel, weir, spillway and baffle. To this end, each panel member as panel member 14 comprises an opaque material which reflects and/or absorbs substantially all light incident thereon. In this regard, it will be readily appreciated that a wide variety of rigid or flexible materials may be utilized for the construction of the panel members. The panel members may, for example, be formed from metal or alloys thereof, fiberglass, or from substantially opaque thermosetting "*r thermoplastic materials. It is also possible, of course, to make the panel member opaque by applying a suitable coating, such as a light reflective or absorptive coating, to the exterior and/or interior surfaces thereof. In so doing, it is possible to utilize even transparent or translucent plastic materials to fabricate the panel members of the present invention. With reference now to FIG. 2, it will be seen that the panel members 14 of cover system 10 may be dimensioned and contoured to achieve a contiguous relationship with the interior surface of the clarifier tank and with each other. In the illustrative embodiment of the present invention depicted in FIGS. 1-3, the clarifier tank has a circular sidewall configuration. Accordingly, each panel member 14 defines an exterior edge surface 14a having a radius of curvature corresponding to the radius of curvature of the tank. Moreover, the lateral side surfaces 16a, 16b of panel member 14 diverge in a direction toward exterior edge surface 14a so that adjacent panel members may be mounted in an end to end abutting fashion. To prevent light from entering the channel between the adjacent lateral edge surfaces of abutting panel members, lateral overlapping regions 17a and 17b are provided (FIG. 3). When panel members 14 are assembled in the manner shown in FIG. 2, a cover system is formed which extends substantially around the entire clarifier tank over the launder channel. Light is thereby prevented from reaching the interior surfaces of the launder channel, spillway, weir, and baffle. In a currently preferred implementation, the individual covers are fabricated from a molded reinforced fiberglass composite as a one piece, unitarily-integrated unit. Thus, each molded cover incorporates the panel member, and, if desired, an end bracket or flange to facilitate securing of the panel member to the clarifier tank. Advantageously, this enables significant reductions in both manufacturing time and for installation as compared to other prior art arrangements and systems. Most preferably, the thickness of the fiberglass panels is in the range of about 3/16 to 3/4 of an inch, a range that provides substantial structural strength and rigidity while remaining sufficiently light weight for unusual ease of installation. Each panel member 14 can also be provided with a network of cross braces or other strengthening members (not shown) to enhance the rigidity to each panel member and provide a walkway surface capable of supporting one or more maintenance workers. Typically, such cross braces or other strengthening members can be fabricated out of a lightweight material such as balsa wood which can then be sandwiched between two or more layers of fiberglass. If desired, the upper surface of each panel member may be provided with a roughened, non- skid texture to prevent injury to such workers. As will be readily appreciated by those skilled in the art, a variety of fastening devices and techniques may be used to secure panel members 14 in position over the launder channel C. In the embodiment shown in FIG. 1 , panel member 14 incorporates an upwardly extending, mounting flange portion 18 having an exterior surface contoured for contiguous engagement with the interior, circumferential surface of clarifier tank 12. Mounting flange portion 18 may be secured directly to the peripheral wall of the clarifier Uuik using conventional mechanical fasteners at radially spaced intervals. As seen in FIG. 1, it will be seen that each panel member 14 may also be provided with one or more mounting flange portions 20 having a radius of curvature corresponding to that of the substantially vertical, inner surface of weir W. Of course, the length of flange portions 20 must be relatively short so as not to substantially obstruct the flow of clean water over the weir. When secured to weir W by appropriate fastening means , second mounting flange portions 20 maintain the lower edge of panel member 14 in fixed position relative to the launder channel and thus the panel member 14 is mounted in cantilever fashion over the weir and spillway. Advantageously, the second mounting flange portions 20 may be provided with a vertical arrangement of slots or grooves (not shown) to allow vertical adjustment relative to the weir and, thus, adjustment of the panel member 14. In this way, the horizontal axis of the panel members can be adjusted if desired. The top surface of each panel member may be provided with handle means, such as recessed regions 22 (. 2) for facilitating the installation or removal of the cover. Service personnel may thus easily remove the covers by hand to access the launder channel for regular scheduled maintenance. When it is anticipated that frequent access to the channel may be required, the cover can be secured to the interior wall or other surfaces of tank 12 and/or the weir W by a series of corrosion resistant retaining members. In the illustrative embodiment of FIGS. 1-3, the retaining members are configured as resilient clips which act to secure each cover over the channel in much the same way as the previously described upper and lower mounting flanges. A plurality of upper clips, only one of which - generally indicated at 24 - is shown, are mounted on the peripheral wall and are engageable with an upwardly extending portion of panel member 14. Illustratively, clips 24 may be dimensioned and arranged to receive the upper flange portion 18, as shown in FIG. 1. In a similar manner, a plurality of lower clips, only one of which --generally indicated at 26-- are mounted proximate the weir and engageable with a downwardly depending portion of panel member 14. By way of particular example, clips 26 may be dimensioned and arranged to receive the lower flange portion of panel member 14. It will, however, be readily ascertained by those skilled in the art that the panel members need not include the upper and lower flange structures discussed above and that various clip engageable surface portions may be utilized for the purpose of retaining the panel members in an easily removed condition in accordance with the teachings of the present invention. For example, clips dimensioned and arranged to receive a lower portion of the exterior edge surface 14a may be secured to the interior surface of the peripheral wall of tank 12. Such a configuration would permit each panel member 14 to be secured to the peripheral wall in a cantilevered fashion over the surface of the launder channel. As shown in FIGS. 8 and 9B, clips 13 are dimensioned and arranged to receive a lower portion of the exterior edge surface 14a may be secured to the interior surface of the peripheral wall of tank 12. Similar to the embodiment described above, such a configuration would permit each panel member to be secured to the peripheral wall 12 in a cantilevered fashion over the surface of the launder channel. To effect removal of the panel member of FIG. 1, handles 22 are grasped and an upward vertical force is applied in order to disengage both the upper and lower edges of the cover from retaining members 24, 26. As best seen in FIG. 3, the upper surface of each panel member may also be provided with one or more covered access ports 28 to facilitate inspection of the launder channel. Illustratively, the access ports 28 may be configured as doors 30 which are provided with a hinging means 31 to facilitate service and inspection. With reference now to FIGS. 4-6, there is shown in cross section a modular panel member 114 constructed in accordance with an alternate embodiment of the present invention. As seen in FIG. 4, panel member 114 has a substantially planar upper and lower surface and is secured to opposed interior surfaces of launder channel C by fixed supports 132 and 134. Supports 132 and 134 define upper supporting surfaces 132a, 134a which may be provided with suitable apertures to accommodate the insertion of suitable mechanical fasteners . As shown in FIG. 5, supports 132\ 134 which define downwardly inclined upper support surfaces 132a\ 134aM may be utilized if it is desired to mount panel member 114 in a downwardly inclined orientation. Alternatively, and as shown in FIG. 6, supports 132' ' and 134' ', which define downwardly inclined upper support surfaces 132a" and, 134a" respectively, may be utilized to mount panel member 114 in a downwardly inclined orientation. In FIG. 7, a modified embodiment of the present invention is shown. In this embodiment, panel member 214 is configured specifically for mounting over a dual weir launder trough. In accordance with this embodiment of the present invention, the trough C is defined by first and second sidewalls 212a, 212b and is bounded on either side by corresponding first and second weirs Wj and W 2 . Panel member 214 may be secured in position above trough C using any suitable securing means. In the illustrative embodiment of FIG. 7, the upper and lower surfaces of panel member 214 are provided with an upwardly converging contour. Accordingly, support members 232 and 234, defining correspondingly contoured supporting surfaces 232a and 234a, may be utilized to secure the panel members in position. In FIG. 8, resilient clips 13 are provided and which act to secure each cover 14 over the channel in much the same way as the previously described upper and lower mounting flanges. A plurality of lower clips 13, only one of which - generally indicated at 13 - is shown in FIG. 9B, are mounted on the peripheral wall and are engageable with an downwardly extending portion of panel member 14. Illustratively, clips 13 may be dimensioned and arranged to receive the lower portion of the exterior edge surface 14a. By utilizing the flange portion 20 described earlier, such a configuration would permit each panel member 14 to be secured to the peripheral wall in a cantilevered fashion over the surface of the launder channel. As shown in FIG. 9A, a mounting flange 15 is provided having a radius of curvature corresponding to that of the substantially vertical, peripheral wall of tank 12. Of course, the length of flange portions 15 can be variable but preferable is the length of the cover so as to fully support the cover 14. Specifically, the mounting flange which can be fabricated out of the same material as the cover such a fiberglass, has a first portion 15a that can be secured to the peripheral wall of tank 12 by a appropriate fastening means such as bolts, screws, rivets of the like. When secured to the peripheral wall by a appropriate fastening means, the second portion 15b is adapted to receive and support the lower portion of the exterior edge surface 14a. Thus, the cover 14 may be secured to the interior surface of the peripheral wall of tank 12. As shown in FIGS. 10 and 11, each panel member 14 may also be provided with a shiplap-type joint 17 intregally molded into the panel member 14 so that the adjacent- abutting panel members (not shown) form a smoothly-continuous surface by virtue of a shiplap-type joint through which each panel member 14 are interconnected. This shiplap-type joint 17 allows for the first lateral side of the panel member 14 to be secured to the next adjacent one of said plural panel members (not shown) so that together they form the smoothly-continuous surface. When utilizing this structure, lateral side surfaces 16a (FIG. 2) are preferably not provided, thus allowing for further weight and cost reductions. Moreover, the overlapping of the lateral sides of the panel member 14 prevents unintended leakage or passage of fine particulate matter through the connection between the immediately-adjacent panel members. And still further, this overlap advantageously permits appropriate adjustment, during installation of the inventive cover system, of the relative positions of adjacently- disposed baffle members to compensate It would be understood that the preferred embodiments and examples described are for illustrative purposes only and are not to be construed as limiting the scope of the present invention which is properly delineated only in the appended claims.

Claims: CLAIMS What is claimed is: 1. A cover apparatus for inhibiting the growth of algae on fluid-contacting surfaces of a water treatment tank including a central influent, at least one substantially vertical peripheral wall having an upper and interior surface, a peripheral baffle having inside and outside surfaces, a substantially vertical weir, a spillway, and a launder channel having a width, comprising: cover means, including at least one panel member positionable over at least a portion of the launder channel, for preventing light from reaching interior surfaces thereof, said at least one panel member being dimensioned to span the width of said launder channel and being comprised of a substantially opaque material. 2. The apparatus of claim 1 , wherein said cover means comprises a plurality of panel members, each of said panel members defining a first lateral surface, a second lateral surface, an interior edge surface and an exterior edge surface. 3. The apparatus of claim 2, wherein the tank is substantially circular and the exterior edge surface of each panel member defines a radius of curvature corresponding to that of the peripheral wall of the tank for contiguous engagement therewith. 4. The apparatus of claim 3, wherein the lateral surfaces of said panel members diverge toward said exterior edge surface such that said panel members are positionable in an end-to-end, abutting relation to cover substantially all surfaces of said launder channel. 5. The apparatus of claim 2, wherein each of said panel members comprises a layer of said substantially opaque material. 6. The apparatus of claim 2, wherein each of said panel members is unitarily molded of a translucent reinforced fiberglass composite and said substantially opaque material comprises one of a light reflective and a light absorbing coating on a surface thereof. 7. The cover system of claim 6, wherein said coating is disposed on a bottom surface of each panel member. 8. The apparatus of claim 2, wherein each of said panel members defines an upper mounting flange portion securable to the peripheral wall of the tank. 9. The apparatus of claim 8, wherein each of said panel members further defines a lower mounting flange portion. 10. The apparatus of claim 2, wherein an upper surface of each panel member defines a handle region manipulable by hand to permit installation and removal of the said cover. 11. The apparatus of claim 10, wherein said handle region is a recess defined in said upper surface. 12. The apparatus of claim 2, wherein an upper surface of each panel member defines access openings therethrough to facilitate inspection of the launder channel, and wherein said cover means further includes means for selectively closing said access openings. 13. The apparatus of claim 2, wherein each of said panel members defines a downwardly sloping upper surface in a direction from the peripheral wall. 14. The apparatus of claim 2, wherein each panel member defines an upwardly extending portion and wherein said cover means further comprises a plurality of retaining members securable to said peripheral wall, said retaining members being dimensioned to receive said upwardly extending portions and thereby retain said panel members in position above the launder channel. 15. The apparatus of claim 2, wherein each panel member defines a downwardly extending portion .and wherein said cover means includes a plurality of retaining members positionable proximate said substantially vertical weir, said retaining members being dimensioned to receive said downwardly extending portions and thereby retain said panel members in position above the launder channel. 16. The apparatus of claim 2, wherein said cover means further includes retaining means securable to said peripheral wall, said retaining means being dimensioned to receive a lower exterior edge portion of each panel member and thereby retain said panel members in a cantilevered orientation above the launder channel. 17. The apparatus of claim 2, wherein each of said lateral surfaces defines an extending lip portion, and wherein said panel members are positionable in an end-to-end configuration in which said lip portions of adjacent panel members overlap. 18. The apparatus of claim 2, wherein said lateral surfaces are lateral edge surfaces. 19. The apparatus of claim 2, wherein said lateral surfaces are sidewall surfaces. 20. A method for inhibiting the growth of algae on fluid contacting surfaces of a water treatment tank including a central influent, at least one substantially vertical peripheral wall having an upper and interior surface, a peripheral baffle having inside and outside surfaces, a substantially vertical weir, a spillway, and a launder channel having a width, said method comprising the steps of: securing to the peripheral tank wall, a first panel member positionable over at least a portion of the launder channel, for preventing light from reaching interior surfaces thereof, said first panel member being dimensioned to span the width of said launder channel and being comprised of a substantially opaque material; and securing to the peripheral tank wall, a second panel member positionable over at least a portion of the launder channel, for preventing light from reaching interior surfaces thereof, said second panel member being dimensioned to span the width of said launder channel and being comprised of a substantially opaque material, said second panel member being secured in end-to-end immediately-adjacent relation to said first panel member. AMENDED CLAIMS [received by the International Bureau on 19 March 1996 (19.03.96); original claim 1 amended; original claims 4, 8, 9, 11, 19 and 20 cancelled; new claims 21-27 added; remaining claims unchanged (5 pages)] 1. (Amended) [A cover apparatus for inhibiting the growth of algae on fluid contacting surfaces of| In a water treatment tank apparatus including [a central] an influent, at least one substantially vertical peripheral wall having an upper and interior surface, [a peripheral baffle having inside and outside surfaces], a substantially vertical weir connected to said vertical peripheral wall, a spillway, and a launder channel having a width, the improvement comprising: cover means, including at least one panel member having first and second ends, said first end being (positionablel secured to the tank and said second end positioned radially outwards from said vertical weir and over at least a portion of the launder channel, for preventing light from reaching interior surfaces thereof, said at least one panel member being dimensioned to span the width of said launder channel and being comprised of a substantially opaque material, whereby the growth of alpae on fluid contacting surfaces of the launder channel is inhibited: and means for supporting said panel member at said substantially vertical wall so that said second end of said panel member is cantilevered over said vertical weir. 2. The apparatus of claim 1, wherein said cover means comprises a plurality of panel members, each of said panel members defining a first lateral surface, a second lateral surface, an interior edge surface and an exterior edge surface. 3. The apparatus of claim 2, wherein the tank is substantially circular and the exterior edge surface of each panel member defines a radius of curvature corresponding to that of the peripheral wall of the tank for contiguous engagement therewith. 5. The apparatus of claim 2, wherein each of said panel members comprises a layer of said substantially opaque material 6. The apparatus of claim 2, wherein each of said panel members is unitarily molded of a translucent reinforced fiberglass composite and said substantially opaque material comprises one of a light reflective and a light absorbing coating on a surface thereof. 7. The cover system of claim 5, wherein said coating is disposed on a bottom surface of each panel member. 10. The apparatus of claim 2, wherein each of said panel members further defines a lower mounting flange portion. 12. The apparatus of claim 2 wherein an upper surface of each panel member defines a access openings therethrough to facilitate inspection of the launder channel, and wherein said cover means further includes means for selectively closing said access openings. 13. The apparatus of claim 2 wherein each of said panel members defines a downwardly sloping upper surface in a direction from the peripheral wall. 14. The apparatus of claim 2, wherein each panel member defines an upwardly extending portion and wherein said cover means further comprises a plurality of retaining members securable to said peripheral wall, said retaining members being dimensioned to receive said upwardly extending portions and thereby retain said panel members in a position above the launder channel. 15. The apparatus of claim 2, wherein each panel member defines a downwardly extending portion and wherein said cover means includes a plurality of retaining members positionable proximate said substantially vertical weir, said retaining members being dimensioned to receive said downwardly extending portions and thereby retain said panel members in a position above the launder channel. 16. The apparatus of claim 2, wherein said cover means further includes retaining means securable to said peripheral wall, said retaining means being dimensioned to receive a lower exterior edge portion of each panel member and thereby retain said panel members in a cantilevered orientation above the launder channel. 17. The apparatus of claim 2, wherein each of said lateral surfaces defines an extending lip portion, and wherein said panel members are positionable in an end-to-end configuration in which said lip portions of adjacent panel members overlap. 18. The apparatus of claim 2, wherein said lateral surfaces are lateral edge W0 96 14126 PCI7US95/14187 surfaces. —21. The apparatus of claim 1 , wherein said water treatment tank apparatus further includes a peripheral scum baffle having inside and outside surfaces, wherein said second end of said panel member is positioned between said vertical weir and said peripheral . cum baffle. -- —22. The apparatus of claim 1 , wherein said means for supporting said panel member has a first end secured to said upper surface of said substantially vertical wall and a second end secured to said panel member.— —23. The apparatus of claim 22, further comprising pivot means secured to said second end of said upper surface of said support means and said panel member for pivoting said panel member between a first substantially horizontal closed position and a second substantially vertical opened position. ~ —24. The apparatus of claim 23, wherein said pivot means further comprises a pivot flange connected to said panel member and a resting flange connected to said upper surface of said support means.— —25. The apparatus of claim 1 , wherein said second end of said panel member terminates at a free end.— —26. The apparatus of claim 1 , further comprising means for releasably securing said first end to said tank.— —27. In a water treatment tank apparatus including an influent, at least one substantially vertical peripheral wall having an upper and interior surface, a peripheral scum baffle having inside and outside surfaces, a substantially vertical weir connected to said vertical peripheral wall, a spillway, and a launder channel having a width, the improvement comprising: cover means, including at least one panel member having first and second ends, said first end being secured to the tank and said second end positioned between said vertical weir and said peripheral scum baffle and over at least a portion of the launder channel, for preventing light from reaching interior surfaces thereof, said at least one panel member being dimensioned to span the width of said launder channel and being comprised of a substantially opaque material, whereby the growth of algae on fluid contacting surfaces of the launder channel is inhibited; means for supporting said panel member at said substantially vertical wall so that said second end of said panel member is cantilevered over said vertical weir and positioned between said vertical weir and said peripheral scum baffle; and pivot means secured to said support means and said panel member for pivoting s-aid panel member between a first substantially horizontal closed position and a second substantially vertical opened position. -- STATEMENT UNDER ARTICLE 19 Claim 1 , as amended, is directed to an apparatus for inhibiting the growth of algae in a water treatment tank. The claim, which has been rewritten in Jepson form claims the tank and cover assembly of the present invention in combination. To this end, the claim recites at least one panel member secured to the tank over at least a portion of the launder channel, for preventing light from reaching interior surfaces thereof. It is further recited that at least one panel member is dimensioned to span the width of the launder channel and that it is substantially opaque. The claim additionally recites the feature that the panel member has first and second ends, the first end being secured to the tank with the second end projecting radially outwards from the vertical weir wall. Additionally, means for supporting the panel member is provided, the support means being positioned at the substantially vertical wall so that the second end of the panel member is cantilevered over the vertical weir.

Inventors: SCHALLER EARLE, SCHALLER, EARLE
Applicants: NEFCO INC, SCHALLER EARLE, NEFCO, INCORPORATED, SCHALLER, EARLE
Application year: 1995
Main classification: B01D21
IPC codes: B01D21, C02F3