Method for enhancing biochemical water treatment by powder carrier

Patent metadata

Field	Value
Publication number	US-11370680-B2
Application number	US-202017029080-A
Country	US
Kind code	B2
Filing date	Sep 23, 2020
Priority date	Nov 19, 2019
Publication date	Jun 28, 2022
Grant date	Jun 28, 2022

Abstract

A method for enhancing biochemical water treatment by a powder carrier includes: (i) screening the powder carrier by removing impurities to obtain a screened powder carrier; (ii) dissolving the screened powder carrier by stirring to prepare a slurry, enabling the screened powder carrier to completely absorb moisture to obtain a soaked powder carrier slurry; (iii) adjusting the pH value and adding the soaked powder carrier slurry into a bioreactor or a biological reaction structure; (iv) distributing the soaked powder carrier slurry uniformly through a hydraulic agitation; (v) loading a microorganism on the inner pore and wrapping on the surface of the soaked powder carrier slurry to obtain powder-loaded biological floccules; (vi) settling the powder-loaded biological floccules in a sedimentation zone and separating the powder carrier from the microorganism for reuse.

First claim

What is claimed is:

1. A method for enhancing a biochemical water treatment by a powder carrier, comprising:
1) selecting a predetermined amount of the powder carrier to be added, removing impurities with a large particle size by a screen to obtain a screened powder carrier;
2) adding a solvent into the screened powder carrier and stirring until the screened powder carrier is completely wetted and does not float upwards in lumps to obtain a soaked powder carrier slurry;
3) adjusting a pH value of the soaked powder carrier slurry to be neutral, and adding the soaked powder carrier slurry into a bioreactor or a biological reaction structure;
4) distributing the soaked powder carrier slurry uniformly in the bioreactor or the biological reaction structure through a hydraulic agitation;
5) loading a microorganism into the bioreactor or the biological reaction structure, and through the hydraulic agitation, allowing the microorganism to fill inner pores of the screened powder carrier and form a biofilm adhered on a surface of the screened powder carrier in the soaked powder carrier slurry to obtain powder-loaded biological floccules;
6) settling the powder-loaded biological floccules in a sedimentation zone after passing through a biological reaction zone and separating the screened powder carrier of the powder-loaded biological floccules from the microorganism of the powder-loaded biological floccules by a separator for reuse.

2. The method according to claim 1 , wherein in step 1, the powder carrier is at least two selected from the group consisting of diatomite, powdered activated carbon, zeolite powder, volcanic rock powder, talc powder and fly ash.

3. The method according to claim 1 , wherein the screen used in step 1 is greater than 200 mesh.

4. The method according to claim 1 , wherein of the powder carrier has a particle size of 10-74 μm.

5. The method according to claim 1 , wherein the powder carrier has an inner surface area of 30-70 m 2 /g, a loss on ignition of the powder carrier is 0-40%, and a bulk density of the powder carrier is 0.1-1.0 g/m 3 .

6. The method according to claim 1 , wherein in step 2, the powder carrier is soaked in wastewater, purified water, or tap water.

7. The method according to claim 1 , wherein in step 3, the pH value is adjusted by slowly replacing a supernatant of the soaked powder carrier slurry, or the pH value is adjusted by adding the soaked powder carrier slurry to a biochemical tank directly.

8. The method according to claim 1 , wherein in step 3, a method of adding the soaked powder carrier slurry is as follows:
stirring the soaked powder carrier slurry by an agitation vat to obtain a diluted and wetted slurry, and adding the diluted and wetted slurry into a biochemical tank by a directional spraying device; or
after the powder carrier is stirred and wetted by the agitation vat to obtain the soaked powder carrier slurry, adding the soaked powder carrier slurry into the biochemical tank by a dry throwing machine.

9. The method according to claim 1 , wherein in step 3, after the soaked powder carrier slurry is added, a concentration of the powder carrier in the bioreactor or the biological reaction structure is 2 g/L-20 g/L.

10. The method according to claim 1 , wherein in step 3, a total effective volume of the bioreactor or the biological reaction structure is 8-1000 m 3 .

11. The method according to claim 1 , wherein in step 4, an inert filler is added to the bioreactor or the biological reaction structure to increase a concentration and a viscosity of the soaked powder carrier slurry, and help forming the biofilm.

12. The method according to claim 1 , wherein in step 4, an inert filler is added to the bioreactor or the biological reaction structure; and
the inert filler is a fixed carrier with an aldehyde fiber or polyester filament as a support body and a plastic sheet as a stent; or the inert filler is a plastic carrier, and the plastic carrier is polypropylene granular inert materials and difficult to be degraded by the microorganism.

13. The method according to claim 1 , wherein in step 5, a bacterial agent or sludge is added as the microorganism, and a mass ratio of the bacterial agent or the sludge to the soaked powder carrier slurry is (1:1)-(4:1).

14. The method according to claim 1 , wherein in step 6, the powder-loaded biological floccules are natural settled in the sedimentation zone, or chemical settled with a flocculant.

15. The method according to claim 1 , wherein in step 6, a sludge scraping apparatus with a small angular velocity is arranged on a tank wall and a bottom slope surface of the sedimentation zone, and the sludge scraping apparatus is configured for scraping wall-adhered biological floccules and stirring the powder-loaded biological floccules settled at a bottom of the sedimentation zone, so as to prevent dead mud formation and hardening.

16. The method according to claim 1 , wherein in step 6, the screened powder carrier and the microorganism are separated by a force, and the force does not damage physical properties of the screened powder carrier.

17. The method according to claim 16 , wherein the screened powder carrier and the microorganism are separated through a centrifugal action, a gravity effect, or a thermal action of combustion.

18. A method for enhancing a biochemical water treatment by a powder carrier, comprising:
1) selecting a predetermined amount of the powder carrier to be added, removing impurities with a large particle size by a screen to obtain a screened powder carrier;
2) adding the screened powder carrier directly into a bioreactor or a biological reaction structure, and soaking the screened powder carrier with s solvent in the bioreactor or the biological reaction structure until the screened powder carrier is completely wetted and does not float upwards in lumps to obtain a soaked powder carrier slurry;
3) adjusting a pH value of the soaked powder carrier slurry to be neutral;
4) distributing the soaked powder carrier slurry uniformly in the bioreactor or the biological reaction structure through a hydraulic agitation;
5) loading a microorganism into the bioreactor or the biological reaction structure, and through the hydraulic agitation, allowing the microorganism to fill inner pores of the screened powder carrier and form a biofilm adhered on a surface of the screened powder carrier in the soaked powder carrier slurry to obtain powder-loaded biological floccules;
6) settling the powder-loaded biological floccules in a sedimentation zone after passing through a biological reaction zone and separating the screened powder carrier of the powder-loaded biological floccules from the microorganism of the powder-loaded biological floccules by a separator for reuse.

Assignees

• Univ Tongji

Inventors

• Chai Xiaoli
• Dai Xiaohu
• Lu Bin
• Wu Boran

Classifications

• C02F1/66

  by neutralisation; pH adjustment (for degassing C02F1/20; using ion-exchange C02F1/42; for flocculation or precipitation of suspended impurities C02F1/52; for removing dissolved compounds C02F1/58) · CPC title

• C02F2003/003

  using activated carbon or the like · CPC title

• C02F11/06

  by oxidation (incinerators for burning waste liquors, e.g. sulfite liquor from paper-making plant F23G7/04) · CPC title

• C02F2001/007

  Processes including a sedimentation step · CPC title

• C02F2203/004

  comprising a selector reactor for promoting floc-forming or other bacteria · CPC title