Acoustically excited encapsulated microbubbles and mitigation of biofouling

Patent metadata

Field	Value
Publication number	US-11007287-B2
Application number	US-201716078315-A
Country	US
Kind code	B2
Filing date	Feb 24, 2017
Priority date	Feb 25, 2016
Publication date	May 18, 2021
Grant date	May 18, 2021

Abstract

Provided herein is a universally applicable biofouling mitigation technology using acoustically excited encapsulated microbubbles that disrupt biofilm or biofilm formation. For example, a method of reducing biofilm formation or removing biofilm in a membrane filtration system is provided in which a feed solution comprising encapsulated microbubbles is provided to the membrane under conditions that allow the encapsulated microbubbles to embed in a biofilm. Sonication of the embedded, encapsulated microbubbles disrupts the biofilm. Thus, provided herein is a membrane filtration system for performing the methods and encapsulated microbubbles specifically selected for binding to extracellular polymeric substances (EFS) in a biofilm.

First claim

What is claimed is:

1. A method of reducing biofilm formation or removing biofilm in a membrane filtration system, the method comprising:
providing a feed solution to a membrane filtration system, wherein the feed solution comprises encapsulated microbubbles;
allowing the encapsulated microbubbles from the feed solution to fully embed, over time, in a biofilm in the membrane filtration system; and
sonicating the encapsulated microbubbles, which are fully embedded in the biofilm on the membrane filtration system, at a frequency and amplitude that does not cause acoustic cavitation of the encapsulated microbubbles but oscillation between expansion and contraction to disrupt the biofilm.

2. The method of claim 1 , wherein the encapsulated microbubbles comprise:
a gas core; and
an encapsulation shell comprising a ligand, wherein the ligand binds one or more extracellular polymeric substances in the biofilm.

3. The method of claim 2 , wherein the ligand is selected from the group consisting of a lipid, a protein, or a polymer.

4. The method of claim 1 , wherein the membrane is a polymeric membrane or a ceramic membrane.

5. The method of claim 1 , wherein the feed solution is selected from the group consisting of fresh water, ground water, brackish water, sea water, waste water, and industrial waste water.

6. The method of claim 1 , wherein the membrane filtration system comprises one or more of the group consisting of a reverse osmosis system, a microfiltration system, an ultrafiltration system, a nanofiltration system, a forward osmosis system, and a membrane distillation system.

7. The method of claim 1 , wherein the sonicating step comprises applying sonic waves with a transducer to the membrane filtration system at the resonance frequency of the encapsulated microbubbles.

8. The method of claim 7 , wherein the sonicating step comprises applying ultrasonic waves to the membrane filtration system.

9. The method of claim 1 , further comprising:
producing the encapsulated microbubbles; and
supplying the produced encapsulated microbubbles to the feed solution by an encapsulated microbubble feed line.

10. The method of claim 9 , further comprising:
collecting a retentate comprising the disrupted biofilm and the encapsulated microbubbles; and
treating the retentate with ultrasonic waves, wherein the ultrasonic waves causes cavitation of the encapsulated microbubbles and sonoluminescence of the retentate.

Assignees

• Univ King Abdullah Sci & Tech

Inventors

• Qamar Adnan
• Fortunato Luca
• Leiknes Torove

Classifications

• B01D2311/04

  Specific process operations in the feed stream; Feed pretreatment · CPC title

• B01D2321/18

  Use of gases · CPC title

• B01D2321/2075

  Ultrasonic treatment · CPC title

• B01J13/04

  by physical processes, e.g. drying, spraying · CPC title

• F28G7/00

  Cleaning by vibration {or pressure waves} · CPC title