Media holding plate for block-type culvert system

Abstract

A medium-retaining plate for a drainage system is provided, having one or more filter blocks. The plate may include a first slot configured to allow air passage and a second slot configured to allow water passage during air backwashing. The medium-retaining plate is configured to facilitate backflow of water into one or more filter blocks through the second slot while maintaining airflow through the first slot to generate optimal collapse pulses. The first and second slots are of uniform size and evenly spaced to facilitate the generation of relatively small collapse pulses during continuous air-water backwashing. Multiple inserts may be arranged around the base of the bottom surface of the medium-retaining plate. The inserts improve the structural integrity of the medium-retaining plate and prevent the medium-retaining plate from lifting.

Description

Technical Field

[0001] The present invention relates to a media holding plate for a block-type culvert system, and more particularly to a media holding plate having a plurality of fluid slots.

Background Art

[0002] Water, wastewater, and industrial filtration systems are used to filter particles suspended in the target fluid. These systems have a culvert system for supporting the filter medium and separating, without limitation, filter media such as sand and anthracite from the bottom of the filter. The filter medium can remove fine particles including dirt and debris, together with chemical or biological contaminants, from the fluid flowing through the filter medium. The formation of culvert blocks is often used to construct culvert systems.

[0003] Figures 1A and 1B respectively show a plan view and a cross-sectional view of the applicant's culvert block 10 disclosed in Patent Document 1, the content of which U.S. Patent is incorporated herein in its entirety. The culvert block 10 has an upper wall 5, a bottom wall 6, a pair of opposing end walls 20, and a pair of opposing side walls 15. The culvert block 10 also includes a central separation wall 25 that extends horizontally between the pair of opposing end walls 20. The central separation wall 25 extends vertically from the upper wall 5 or near it to the bottom wall 6. The central separation wall 25 can divide the culvert block 10 into two longitudinal portions. Lateral separation walls 50 may be formed in each longitudinal portion, thereby forming a primary side channel 35 (or primary distribution conduit) and a secondary side channel 40 (or secondary distribution conduit). The lateral separation wall 50 separates the primary side channel 35 from the secondary side channel 40. Further, the central separation wall 25 separates the primary side channels 35 from each other and the secondary side channels 40 from each other.

[0004] The drain block 10 may include openings 30 formed therein. As used herein, the term “opening” refers to any kind of hole, gap, crack, slit, or void. In the drain block shown in Figures 1A and 1B, the openings 30 are formed in the central separation wall 25 at both ends of the central separation wall 25, along the direction in which the central separation wall 25 extends between a pair of opposing end walls 20. The openings 30 may be through holes that extend all or substantially through the height of the central separation wall 25. The height of the central separation wall 25 refers to the distance the central separation wall 25 extends from the top wall 5 or near it to the bottom wall 6. At least one opening 30 formed in the central separation wall 25 of the drain block 10 can receive a support member. The drain block 10 is formed to collect filtered water that has passed through the filter medium. The drain block 10 is thin and can cover the bottom of the filter bed and support the filter medium. The slim design increases the volume of liquid being filtered while reducing the occurrence of biological / chemical scaling.

[0005] In a block-type drainage system, a filter bed surface can be formed by arranging multiple drainage blocks (e.g., multiple drainage blocks 10) end-to-end at the bottom of the filter. The filter medium may be placed on top of the drainage blocks to capture dirt and other particulate matter from the liquid (such as water) being filtered as it passes through the filter medium. The blocks are thin and can cover the bottom of the filter bed while supporting the filter medium. The thin design increases the volume of liquid being filtered and reduces the occurrence of biological / chemical scaling.

[0006] In addition to supporting the filter medium, the drainage system serves two main purposes: to recover the filtered water that has passed through the filter medium, and to uniformly distribute backwash water, backwash air, or a combination of both across the filter. Backwashing is the process of removing solid particles or other undesirable substances from the filter medium by pumping a clean backwash fluid or gas, or a mixture thereof, into the drainage block, either separately or simultaneously. Typically, the backwash fluid is clean water, and the gas used is air.

[0007] The drainage block also forms a barrier to physically separate the filter medium from the air and water distribution channels designed within the block. Separating the filter medium from the block prevents finer particles of the filter medium from clogging the channels. Traditionally, graded gravel layers have been used to prevent the filter medium from passing through to the filter bed surface. However, using a gravel layer reduces the available space for the medium and makes the filter structure deeper. As an alternative to a gravel layer, a medium-retaining plate can be used to prevent the filter medium from passing through the drainage system while also facilitating the replacement of the medium. When in use, each filter block may be pre-assembled with an engaged medium-retaining plate. The medium-retaining plate also helps to hold the filter medium at the top of the drainage block.

[0008] Air can provide an airlift that cleans the filter medium and removes solids released from the filter along with water by being evenly distributed across the entire bottom region of the filter. Air cleaning involves injecting controlled filtered air into the filter medium (or filter or medium; these terms are used interchangeably herein) through a medium holding plate. This process is followed by a water backwash to increase thrust and push particles upward, after which the air is shut off and only water is used to remove the contaminated water containing these particles from the system. By using air and water simultaneously or sequentially, the amount of contaminated backwash water produced is significantly reduced, and the uniform backwash process dramatically lowers operating costs. The pressurized air / water combination prevents filter problems such as mud balls, filter cracking, accumulation of aggregates on medium particles, and inert areas within the filter by allowing filtered water to pass upward through the medium at a sufficient velocity.

[0009] In conventional block-type subsurface filtration systems, the fluid passes through the subsurface blocks at high speed during the backwashing process. The backwash water enters the primary channel, then passes through a control orifice and enters two secondary channels. The backwash air is distributed by the design of the upper control orifice between the primary and secondary channels, providing uniform air distribution. Thus, backwashing improves the performance of the filter medium. This process also results in expansion of the medium bed on the medium holding plate. The medium holding plate plays an important role in the air washing process. [Prior art documents] [Patent Documents]

[0010] [Patent Document 1] U.S. Patent No. 8,343,343 [Patent Document 2] U.S. Patent Application Publication No. 20180333660 [Overview of the Initiative] [Problems that the invention aims to solve]

[0011] Some conventional media-holding plates contain compressed, high-density polymer beads. The use of polymer beads allows for the creation of porous filters / plates that can be used as filter beds and media-holding beds. This process results in pores of varying sizes and with non-uniform spacing between them. While the pores are typically smaller than the conventional filter medium, the filter medium can occasionally penetrate the pores and clog / block the media-holding plate. This reduces the overall efficiency and performance of the filter. The non-uniform pore distribution and varying pore sizes on the media-holding plate also result in a non-uniform flow distribution on the filter bed. The non-uniform pore size and spacing / distribution lead to non-uniform collapse pulse behavior at the top of the filter bed during backwashing. The non-uniform pore distribution, due to the non-uniform collapse pulse effect, can lead to solidification of the filter medium at the top of the filter bed. This invalidates the backwashing process and therefore increases the overall operating cost of the drainage system. Furthermore, conventional media holding plates tend to bend beyond the edges of the filter block, causing leaks in the filter and ultimately resulting in substantial damage to the filter.

[0012] Patent Document 2 discloses a media holding plate having a plurality of hopper-shaped compartments formed on its upper surface, and having a first inclined wall and a second inclined wall inclined toward the first inclined wall in the direction from the upper surface toward the bottom surface. The plate further has at least one first slot extending through at least one of the first and second inclined walls, and at least one second slot extending through the upper side wall. Other prior art media holding plates include upper and lower media holding plates. Potential drawbacks of such designs are that they are difficult to manufacture reproducibly because tolerances between the two plates can accumulate and a mismatch in one plate can cause a failure in the filter assembly. Also, they are more expensive because two parts are required for one filter, and secondary work is increased because the upper and lower plates need to be assembled.

[0013] Therefore, there is a need for improved media holding plates for block-type drainage systems that can ensure optimized fluid flow into the drainage filter block during operation and a uniform flow distribution through the filter medium during the air-water backwashing process. [Means for solving the problem]

[0014] According to one or more embodiments, the present invention relates to an improved medium-retaining plate (also called a “plate”) for block-type drainage systems. In particular, the present invention includes a single (or one) medium-retaining plate for drainage blocks. The medium-retaining plate is configured to have a plurality of precisely engineered slots for the passage of two fluids having different densities. As used herein, the term “slot” includes, but is not limited to, slots, slits, openings, notches, or gaps within the medium-retaining plate. In exemplary embodiments, the first fluid is air and the second fluid is water. Each slot is configured to allow the passage of only one of these fluid types during an air-water backwash process.

[0015] Air and water slots are positioned along the media-holding plate to facilitate optimal flow in and out of the plate while preventing the media from passing through. The plate prevents media loss by passing through the filter bed surface while increasing the available filter headroom.

[0016] The media holding plate promotes an optimal collapse pulse by allowing water to flow back into the filter block through the water holding slots while maintaining airflow through the air distribution slots. This allows for proper agitation of the filter media on the media holding plate through vortices generated on the plate. The collapse pulse effect generates turbulence through the energy dispersion of rising bubbles and allows for expansion of the media bed by separating the media. Proper agitation of the filter media increases the cleaning effect of the filter media and reduces the overall backwash time, thus saving operating costs. This improves the overall performance of the block drainage system by improving the backwash process.

[0017] In conventional block culvert filtration systems, the fluid passes through the culvert filter block at high speed during the backwashing process. This results in an increased velocity flow profile due to the two primary channels in the culvert block. (However, it should be noted that some culvert filter blocks contain only one primary channel.) To regulate the velocity, two secondary channels are installed in the filter block. The two primary and secondary channels allow the flow velocity to be adjusted to a much more stable profile. However, due to the long overall length of these culvert filter systems, it is not possible to guarantee that this stable profile will be maintained. Therefore, in one or more embodiments of the present invention, the slots on the media holding plate are configured on a downwardly inclined surface to stabilize the fluid flow velocity. This ensures that the filter is used optimally in all given situations / conditions. The back pressure on the media holding plate can be essentially reduced by pre-engineered angled slots, while maintaining optimal pressure inside the filter block by increasing the volume between the fluid outlet slot and the orifice.

[0018] In one or more embodiments, to securely position the plate within the filter block, a plurality of inserts or legs are disposed at the base of the bottom surface of the plate. This design also improves the structural integrity of the filter block assembly and prevents the media retaining plate from lifting. During the backwash process, the media retaining filter can be subjected to pressure on its bottom surface. This can cause the filter to be pushed away from the filter block, creating leakage points. This can lead to an overall degradation of system performance and potentially result in system failure. In addition to ensuring structural integrity, the inserts can also ensure that the media retaining plate with the filter bed remains stable under the pressure conditions that occur during the backwash process. In one or more embodiments, the inserts are configured to engage with the filter block, and the media retaining plate can be secured to the filter block by using an adhesive or sealant in conjunction with screws or other fixing means.

[0019] The present invention will be described in more detail below with reference to the accompanying drawings, all of which illustrate, or are related to, the apparatus, system, and method of the present invention. The drawings are not intended to be drawn to scale, and each similar component shown in the various drawings is represented by a similar number.

Brief Description of the Drawings

[0020] [Figure 1A] Shows an exemplary prior art stormwater block. [Figure 1B] Shows an exemplary prior art stormwater block. [Figure 2A] Shows a media retaining plate for a stormwater block according to one embodiment. [Figure 2B] Shows a media retaining plate for a stormwater block according to one embodiment. [Figure 3A] Shows a diagram of a media retaining plate showing double air slots and water slots according to one embodiment. [Figure 3B]Figure showing a media holding plate with double air slots and water slots according to one embodiment. [Figure 3C] Figure showing a media holding plate with double air slots and water slots according to one embodiment. [Figure 4] Side view of a media holding plate with an insert according to one embodiment.

Best Mode for Carrying Out the Invention

[0021] Depending on the context, all references hereinafter to "the present invention" may, in some cases, refer only to a particular embodiment. Various terms are used herein. Unless the terms used in the claims are defined below, the broadest definition given by those skilled in the art as reflected in publications printed at the time of filing and issued patents should be given.

[0022] According to one embodiment, a media holding plate for a stormwater filter block has a top surface, a bottom surface opposite the top surface, a pair of opposing side walls and a pair of opposing end walls connecting the top surface and the bottom surface, a plurality of plate sections formed on the top surface, each internal section including one or more air slots and one or more water slots, and a plurality of inserts disposed along the outer periphery of the base of the bottom surface, each insert being configured to be fixed to the top surface of the stormwater filter block.

[0023] The media holding plate further includes a first set of inner walls, each inner wall of the first set of inner walls extending from the first end wall to the second end wall. The media holding plate further includes a second set of inner walls, each inner wall of the second set of inner walls extending from the first side wall to the second side wall. Each wall of the first set of inner walls intersects the corresponding wall of the second set of inner walls to form a plurality of plate sections. Each plate section further includes a central protrusion, and on both sides of the central protrusion, a pair of opposing downward inclined surfaces are disposed.

[0024] One air slot is positioned along a first intersection, which is formed by the intersection of the lower edge of the central projection and the first end of each downward-sloping surface. Similarly, a pair of air slots may be formed on either side of the central projection along the intersection of the lower edge of the central projection and the first end of each downward-sloping surface. The air slots extend along the width of the first intersection.

[0025] One water slot is formed along a second intersection, which is formed by the intersection of the second end of a downward-sloping surface and the upper part of the bottom surface of the media-holding plate. Similarly, a pair of water slots may be formed by the intersection of the second end of each downward-sloping surface and the bottom surface of the media-holding plate. The water slots extend along the width of the second intersection.

[0026] The width of one or more air and water slots is pre-designed to ensure the retention of the filter medium placed on the medium holding plate. The medium-holding plate is configured to facilitate the backflow of water into the drainage block through one or more water slots while maintaining airflow through one or more air slots to generate optimal collapse pulses. The one or more air slots and water slots are of uniform size and evenly spaced to facilitate the generation of relatively small collapse pulses during continuous air-water backwashing.

[0027] According to another embodiment, a method for manufacturing a media holding plate for a drainage filter block, having a top surface, a bottom surface opposite the top surface, a pair of opposing side walls and a pair of opposing end walls connecting the top surface and the bottom surface together, a plurality of plate sections formed on the top surface, each internal section including one or more air slots and one or more water slots, and a plurality of inserts arranged along the outer circumference of the base of the bottom surface, each insert configured to be fixed to the top surface of the drainage filter block, involves using a pair of first and second mold blocks to form first and second slots. The method further involves pushing the first mold block upward toward a central projection to form one or more air slots, and pushing the second mold block downward toward a downward inclined surface to form one or more water slots.

[0028] As shown in Figures 2A to 2B, the present invention includes an improved media-holding plate for a drainage system having at least one drainage block (such as drainage block 10 disclosed in Figures 1A to 1B). The media-holding plate is configured to be attached to the top of the drainage block. One or more layers (not shown) of filter media can be placed on the media-holding plate. The filter media may be any type known in the art. For example, it may include, but is not limited to, sand or gravel.

[0029] The media holding plate has evenly (or consistently) sized and evenly spaced slots for the inflow and outflow of air and water. The slots are further configured to have angular contours and are separated by baffles or side walls. The slots can prevent the filter media from passing through the filter block to prevent media loss during the process flow. The slots are configured to achieve a consistent and well-distributed backwash fluid flow through the media holding plate into the filter media bed.

[0030] The size and spacing of the slots facilitate the generation of relatively small-sized collapse pulses during backwashing, due to the fluid pressure difference on the upper surface of the media holding plate. Smaller collapse pulses allow for higher energy dissipation in the filter medium and promote agitation of the medium for proper cleaning. The surface of the filter medium can be cleaned using the vortices generated during the backwash flow by the angled slots with separation baffles. The filter medium and media holding plate are optimally cleaned using the agitation of the filter medium caused by the collapse pulses.

[0031] One or more embodiments of the present invention improve the back pressure handling capacity of a block drainage system by utilizing a double air slot and water slot and insert having a predetermined width on the bottom surface of a media holding plate. Furthermore, by utilizing separate air slots and water slots, water retention during process flow and air washing backwash is improved.

[0032] As shown in Figures 2A and 2B, the filter medium holding plate 100 has a top surface 107 and an opposite bottom surface 108. The medium holding plate 100 is configured to extend longitudinally between the ends of a drainage block (not shown). The first pair of opposing side walls 101c and 101d are arranged substantially parallel to each other, and the second pair of opposing end walls 101a and 101b are arranged substantially parallel to each other. Each side wall is connected to the end walls 101a and 101b. Furthermore, the opposing side walls and end walls connect the top and bottom surfaces of the medium holding plate 100. The medium holding plate 100 may be rectangular or square in shape. However, it should be understood that the medium holding plate 100 may have any other suitable shape. The medium holding plate 100 further has a pair of inner walls 102. The inner wall 102a of the first set extends longitudinally from end wall 101a to end wall 101b, perpendicular to the side walls 101c and 101d. The inner wall 102a of the first set is arranged in a linear pattern from near side wall 101a to near side wall 101b. Similarly, the inner wall 102b of the second set is configured to extend perpendicularly to the end walls 101a and 101b from the first side wall 101c to the second side wall 101d. The inner wall 102b of the second set is arranged in a linear pattern from near side wall 101c to near side wall 101d. The addition of the inner walls 102 improves the overall structural integrity of the media holding plate 100. Each wall of the inner wall of the first set intersects with the corresponding wall of the inner wall of the second set to form a plurality of plate compartments or plate sections 103 (described below). The intersecting inner walls function as baffle walls or separation walls for air slots and water slots (120 and 130) formed on the surface of the media holding plate 100.

[0033] As bubbles move upward through the media bed for proper cleaning of the filter medium, the bubbles collapse, and the resulting collapse pulse effect creates vortices that can agitate the filter medium (not shown) placed on the media holding plate 100. The collapse pulse is caused by the pressure difference between the high pressure at the bottom of the plate 108 and the low pressure at the top 107 of the media holding plate 100.

[0034] The media retention plate 100 is configured to securely fit or connect to a conventional filter block (not shown) for a drainage system in order to prevent loss of filter media and to better maintain backwash pressure. Furthermore, since the media retention plate 100 substantially eliminates loss of filter media, the operating cost of the backwash process is reduced. This improves the overall performance of the drainage system by improving the backwash process due to the improved air and water flow through the filter block.

[0035] Referring to Figures 3A to 3C, each plate compartment / section 103 includes a central projection 106, on either side of the central projection 106 are a pair of downward-sloping surfaces / angled surfaces 104. Part of each inclined surface 104 may include a notch 112.

[0036] Each of the plate sections 103 is configured to have slots for two different fluid types, namely, a slot for air and another slot for water. It is understood that one or more slots may be formed in each plate section for each of these fluid types. For example, an air slot 120 may be formed along the intersection 105 of the lower edge of the projection 106 (having an upper and lower edge) and one or both first (or upper) ends of the downward-sloping surface 104. The air slot 120 has a predetermined length and extends along all or part of the width of the intersection 105. A water slot 130 is formed along the intersection 115 of the second (or lower) ends of one or both of the downward-sloping surface 104 and the upper part 108A of the bottom surface of the media-holding plate. The water slot 130 has a predetermined length and extends along all or part of the width of the intersection 106. The widths of the air slot 120 and the water slot 130 are precisely designed to prevent the filter medium from passing through.

[0037] Patent Document 2 also discloses both water slots and air slots, however, the water slots of the present invention do not extend through the inclined wall, and the air slots of the present invention do not extend through the upper side wall. Instead, the arrangement of the air and water slots in the present invention facilitates the maintenance of optimal pressure within the drainage block, thereby ensuring the effectiveness of the drainage block and reducing the back pressure generated by the medium-holding plate 100 on the drainage system. To ensure that the filter operates under optimal conditions while backwashing with air, air-water, and water only, slots 120 and 130 on the inclined surface 104 are utilized in two different ways. The air slot 120 is utilized during air washing. The water level within the filter block is maintained by returning water into the drainage block using the water slot 130. The water slot 130 ensures that optimal fluid flow is maintained during the operation of the drainage system.

[0038] During the backwashing process, the fluid slots (120, 130) serve as inlet and outlet points for the corresponding fluids (air, water) in an upward direction perpendicular to the upper surface 107 and bottom surface 108 of the media holding plate.

[0039] The angle of the inclined surface (downward inclined surface 104) can be preset using the relationship between pressure and volume with respect to the distance between fluid slots 120 and 130 on these surfaces 104 to improve / reduce the back pressure generated on the filter medium by the medium holding plate 100. Furthermore, an optimal pressure can be maintained inside the filter block to ensure the effectiveness of the filter block and to reduce the back pressure generated by the medium holding plate 100 on the underground drainage system.

[0040] The slots 120 and 130, by being configured with a predetermined consistent slot size, enable a uniform flow distribution out of the filter during the backwashing process and optimize the flow entering the filter block during the operating flow. In exemplary embodiments, each slot may have a width of (but not limited to) 0.008 inches (0.2032 mm) or 0.2 millimeters. In one or more embodiments, the slots extend through the depth of the plate to the bottom surface 108 of plate 100. In addition, the location / position of the air and water slots (120, 130) enables optimal flow into and out of the media-holding plate 100. Each fluid flows into its respective slot (120, 130) due to differences in fluid density. The inclined surface 104 further stabilizes the flow velocity profile. By increasing the volume between the fluid slots and the top surface 107, the back pressure generated by the original media-holding plate is reduced by the inclined surface 104 of plate section 103 while maintaining optimal pressure inside the drainage block.

[0041] Furthermore, slots 120 and 130 on the inclined surface 104 assist the backwashing process. Air, water, and combinations of these two fluids can pass through the filter plate in the opposite direction to the process flow during backwashing. The air slot 120 agitates the medium on the filter plate 100 using the resulting collapse pulses by allowing air to pass through the medium holding plate 100 and enter the filter medium. The collapse pulses can wash the medium by turbulence and agitation of the medium on the surface 107 of the medium holding plate 100. This process also allows for proper expansion of the filter bed and separation of the medium according to gravity of the individual media being agitated. In addition, during air-only backwashing, the water slot 130 maintains the air-to-water distribution ratio within the filter block by allowing water to remain in the filter. The water slot 130 also plays an important role in the process flow by maintaining proper fluid flow.

[0042] Figure 4 shows a side view of a media holding plate 100 having a top surface 107 configured for holding filter media and a bottom surface 108. Conventionally, during the air-water backwashing process, the media holding plate is subjected to pressure on its bottom surface. This can push the filter away from the filter block, creating leaks and causing an overall decrease in the performance and efficiency of the system. Advantageously, the media holding plate 100 is configured to have a plurality of inserts or legs 109 attached to the base 108B of the bottom surface 108 of the media holding plate 100. The inserts 109 may be fixed to the drain block using fastening means (not shown), such as sealant or adhesive, in conjunction with screws, to improve the overall structural integrity of the media holding plate 100 and prevent the media holding plate from lifting. This improves the back pressure handling capacity of the media holding plate 100.

[0043] In another embodiment, a method for manufacturing the media-holding plate 100 involves creating two types of fluid slots 120, 130 as described herein by using a custom mold. The air slots 120 and water slots 130 can be precisely machined on the inclined surface 104 of the media-holding plate 100 by utilizing a pair of relatively large blocks (not shown) made of metal or other suitable material in order to maintain the desired fluid flow characteristics. Conventionally, a piece of metal of the desired slot size is used in the mold to create the slot. Advantageously, the manufacturing of the media-holding plate of the present invention avoids the use of such a piece of metal in the mold. While forming the air and water slots in the media-holding plate of the present invention, a relatively large mold block / piece, the size of the notch (112), is used in the mold. The corners or edges of this mold block are utilized to create gaps of the desired / predetermined size by precisely passing them over the surface of the media-holding plate 100. In an exemplary embodiment, the water slot 130 can be formed by pressing the first mold block downward against the inclined surface 104. The air slot 120 can be formed by pushing the second mold block piece upward toward the protrusion 106. This makes the molding / manufacturing process easier and extends the mold's lifespan. The slot gap is created using a larger piece of metal, which is the size of the notch rather than the slot size, thus preventing the mold from wearing, breaking, or bending over multiple cycles. This improves the mold's lifespan and efficiency. Furthermore, this makes it possible to create small, precise slot sizes, such as 0.0008 inches (0.02032 mm), which would not be complex or difficult using conventional manufacturing techniques.

[0044] Accordingly, the present invention is well adapted to achieve the purposes and benefits mentioned, as well as purposes and benefits specific to the present invention. The foregoing description is not intended to limit the present invention and can be used in different aspects or embodiments without departing from the scope of the invention. Discussions of acts, materials, apparatus, articles, etc., are included herein solely for the purpose of providing the context of the present invention. It is not implied or presented that any or all of these matters formed part of the basis of the prior art or were common general knowledge in the art relating to the present invention.

[0045] Furthermore, the specific exemplary embodiments disclosed above may be modified or altered, and all such modifications are considered to be within the scope and spirit of the invention. While the media-holding filters and methods of use of the present invention are described in terms of "equipping," "containing," or "incorporating" various devices / components or steps, it should be understood that systems and methods may also "essentially consist of" or "consist of" various components and steps. Whenever a numerical range with lower and upper limits is disclosed, any number and any range included within that range is specifically disclosed. In particular, any range of values ​​disclosed herein (in the form of "about a to about b," or equivalently "about a to b") should be understood to indicate any number and range that are included within a broader range of values. If there is any inconsistency in the usage of a word or term in this specification and in one or more patents or other documents that may be incorporated herein by reference, the definition consistent with this specification should be adopted.

Claims

1. A media holding plate for a drainage filter block, The top surface and the bottom surface opposite the top surface, A pair of opposing side walls and a pair of opposing end walls connect the top surface and the bottom surface, A plurality of plate sections formed on the upper surface, each plate section having a central projection, a pair of opposing downward-sloping surfaces arranged on both sides of the central projection, and air slots arranged along a first intersection, the first intersection being formed by the intersection of the lower edge of the central projection and the first end of the downward-sloping surface, and a plurality of plate sections. A media holding plate comprising a plurality of legs, each leg being attached to the bottom surface of the media holding plate and fixed to the upper surface of the underground drainage filter block.

2. The media holding plate according to claim 1, further comprising a first set of inner walls, each of the first set of inner walls extending from a first end wall to a second end wall.

3. The media holding plate according to claim 2, further comprising a second set of inner walls, each of the second set of inner walls extending from a first side wall to a second side wall.

4. The media-holding plate according to claim 3, wherein each wall of the first set of inner walls intersects with the corresponding wall of the second set of inner walls to form the plurality of plate sections.

5. The media holding plate according to claim 1, wherein the air slot extends along the width of the first intersection.

6. The media holding plate according to claim 1, wherein water slots are formed along a second intersection, the second intersection being formed by the intersection of a second end of a downwardly inclined surface and the upper part of the bottom surface.

7. The media holding plate according to claim 6, wherein the water slot extends along the width of the second intersection.

8. The media holding plate according to claim 1, wherein the widths of one or more of the air and water slots are pre-designed to ensure the retention of the filter medium placed on the media holding plate.

9. The medium holding plate according to claim 1, wherein the medium holding plate is configured to facilitate the backflow of water into the drainage block through one or more water slots while maintaining an airflow through one or more air slots to generate an optimal collapse pulse.

10. The media holding plate according to claim 1, wherein one or more of the air slots and water slots are of uniform size and evenly spaced apart to facilitate the generation of relatively small-sized collapse pulses during continuous air-water backwashing.

11. A method for manufacturing a media holding plate according to claim 7, comprising manufacturing the first and second slots by utilizing a pair of first and second mold blocks.

12. A method for manufacturing a media holding plate according to claim 11, further comprising pushing the first mold block upward toward the central protrusion to form one or more air slots.

13. A method for manufacturing a media holding plate according to claim 12, further comprising pushing a second mold block downward toward the downward inclined surface to form one or more water slots.

Images