Granular green sorbent media for filtration of contaminated water

Patent metadata

Field	Value
Publication number	US-11673114-B2
Application number	US-202016840165-A
Country	US
Kind code	B2
Filing date	Apr 3, 2020
Priority date	Apr 4, 2019
Publication date	Jun 13, 2023
Grant date	Jun 13, 2023

Abstract

Filter media for treating contaminated water is produced from aluminum-based water treatment residuals (Al-WTR) commonly produced as a byproduct of water treatment plants. By processing the residuals into small granules, a superior green sorbent product is obtained with the functionality to adsorb contaminants, such as metals and certain nutrients in water. Biopolymers can be incorporated into the filter media to further enhance functionality and hydraulic characters.

First claim

The invention claimed is:

1. A filter media for treating contaminated water, comprising a plurality of particles of powdered aluminum-based water treatment residuals, each particle of at least some of said plurality of particles being entrapped in a corresponding shell which includes calcium and potassium alginate.

2. The filter media of claim 1 , wherein there are a plurality of entrapped particles, said entrapped particles being in the form of granules.

3. The filter media of claim 2 , wherein said granules have varying sizes.

4. The filter media of claim 3 , wherein said granules have a spherical shape with a diameter of approximately 2-5 mm.

5. The filter media of claim 4 , wherein said granules have a specific density of approximately 1.22-1.25 g/ml.

6. The filter media of claim 2 , wherein said granules are non-toxic.

7. The filter media of claim 2 , wherein said granules are water insoluble.

8. The filter media of claim 2 , wherein said granules have a hydraulic conductivity sufficient to allow water flow therethrough without becoming too tightly packed in response to water flowing through said granules.

9. The filter media of claim 8 , wherein said granules function as adsorbents for contaminants in water flowing through said granules.

10. The filter media of claim 9 , wherein said granules function as adsorbents for nutrients in water flowing through said granules.

11. The filter media of claim 2 , wherein said granules constitute a green sorbent product.

12. The filter media of claim 1 , wherein said particles have an oxalate-extractable aluminum concentration greater than 100 ppm.

13. The filter media of claim 1 , wherein said aluminum-based water treatment residuals are the byproduct of drinking water treatment plants.

14. The filter media of claim 13 , wherein said aluminum-based water treatment residuals are dry.

15. The filter media of claim 14 , wherein said plurality of particles are the product of a grinding process.

16. The filter media of claim 15 , wherein said plurality of particles are non-toxic.

17. The filter media of claim 16 , wherein said plurality of particles have an oxalate-extractable aluminum concentration greater than 100 ppm.

18. The filter media of claim 17 , wherein said plurality of particles are micron-sized.

19. The filter media of claim 17 , wherein said plurality of particles are nano-sized.

20. The filter media of claim 1 , wherein said filter media functions as an adsorbent for contaminants and nutrients in storm water.

Assignees

• Stevens Institute Of Technology

Inventors

• Sarkar Dibyendu
• Na Nagara Viravid
• Datta Rupali

Classifications

• B01D2239/10

  Filtering material manufacturing · CPC title

• B01D2239/0283

  comprising filter materials made from waste or recycled materials · CPC title

• C02F1/281

  using inorganic sorbents · CPC title

• B01J20/24

  Naturally occurring macromolecular compounds, e.g. humic acids or their derivatives · CPC title

• B01J20/08

  comprising aluminium oxide or hydroxide; comprising bauxite · CPC title