Porous Pavement for Water Quality and Quantity Management

Abstract

A sorptive-filtration system for removing at least one of negatively or positively charged ions, complexes or particulates from an aqueous stream. The system includes a) flow formed substantially from at least one of rainfall-runoff or snowmelt-runoff; b) a filter containment communicating with the runoff stream such that at least part of the stream passes through the filter containment; and c) a granular filter media disposed within the filter containment, the filter media having an amphoteric material applied thereto, wherein the amphoteric material comprises a metal selected from at least one of Fe, Al, Mn, or Si.

1 . A sorptive-filtration system for removing at least one of negatively or positively charged ions, complexes or particulates from an aqueous stream, comprising:
 a. flow formed substantially from at least one of rainfall-runoff or snowmelt-runoff;   b. a filter containment communicating with said flow such that at least part of said flow passes through said filter containment; and   c. a granular filter media disposed within said filter containment, said filter media comprising an amphoteric material applied thereto, wherein said amphoteric material comprises a metal selected from at least one of Al, Mn, or Si.   
     
     
         2 . The filtration system of  claim 1 , wherein said amphoteric material is at least one oxide of a metal selected from at least one of Al, Mn, or Si. 
     
     
         3 . The filtration system of  claim 1 , wherein said filter media is a granular media having a porosity of between about 0.2 and about 0.7. 
     
     
         4 . The filtration system of  claim 1 , wherein said amphoteric material comprises both an oxide of Si and at least one oxide of a metal selected from at least one of Al, Mn, or Fe. 
     
     
         5 . The filtration system of  claim 4 , wherein said filter media comprises a first media having a Si oxide applied thereto and a second media having at least one oxide of at least one of Al, Mn, or Fe. 
     
     
         6 . The filtration system of  claim 1 , wherein said filter containment is formed by a porous textile or geotextile material. 
     
     
         7 . The filtration system of  claim 1 , wherein said filter containment is formed by a porous mesh material. 
     
     
         8 . The filtration system of  claim 7  wherein said porous mesh material is a wire mesh. 
     
     
         9 . The filtration system of  claim 1 , wherein said filter system includes a rigid media housing and said filter containment is a flexible material generally shaped to fit within said media housing. 
     
     
         10 . The filtration system of  claim 3 , wherein said filter media is a granular media having a hydraulic conductivity of between about 1.0 and about 0.0001 cm/sec. 
     
     
         11 . The filtration system of  claim 1 , wherein said media has a specific gravity of between about 0.2 and about 1.0. 
     
     
         12 . The filtration system of  claim 1 , wherein said media has a specific gravity of between about 0.2 and about 1.0. 
     
     
         13 . The filtration system of  claim 1 , wherein said media comprises a granular substrate having an average diameter ranging from 0.1 mm to 100 mm. 
     
     
         14 . The filtration system of  claim 1 , wherein said granular media is produced by a process comprising the steps of:
 a. providing said granular media;   b. applying an amphoteric solution to said media;   c. drying said media to leave an amphoteric coating thereon.   
     
     
         15 . The filtration system of  claim 14 , wherein said step of applying said amphoteric solution is accomplished by at least one of: i) immersing said media in said amphoteric solution; ii) spraying said amphoteric solution onto said media; or iii) adding an amphoteric solution to a precursor of said media. 
     
     
         16 . The filtration system of  claim 1 , wherein said media is a granular media produced by a process comprising the steps of:
 a. providing said granular media;   b. providing a wet cement mix comprising in part an amphoteric solution;   c. coating said media with said wet cement mix; and   d. hydrating or drying said wet cement mix on said substrate.   
     
     
         17 . The filtration system of  claim 16 , wherein said media has a specific gravity of between about 0.2 and about 1.0 
     
     
         18 . The filtration system of  claim 16 , wherein said media has a specific gravity of between about 1.0 and about 2.4. 
     
     
         19 . The filtration system of  claim 1 , wherein said granular media is produced by a process comprising the steps of:
 a. providing said granular media substrate;   b. coating said media with a wet cement mix;   c. drying said wet cement mix on said substrate; and   d. applying an amphoteric solution to said cement coated substrate.   
     
     
         20 . The filtration system of  claim 1 , wherein said granular media is produced by a process comprising the steps of:
 a. providing a wet cement mix comprising in part an amphoteric solution;   b. drying said wet cement mix; and   c. reducing said dried cement mix into granular form ranging from about 0.01 mm to about 500 mm in average diameter.