Methods for producing high-concentration of dissolved ozone in liquid media

Patent metadata

Field	Value
Publication number	US-10858271-B2
Application number	US-201816046702-A
Country	US
Kind code	B2
Filing date	Jul 26, 2018
Priority date	Mar 28, 2018
Publication date	Dec 8, 2020
Grant date	Dec 8, 2020

Abstract

Disclosed are methods for continuous production of ozone strong water, the methods comprising the steps of injecting an acidification agent into a pressurized feed water to maintain a pH value of the pressurized feed water below 7, diffusing a two-phase mixture of O 2 -O 3 gas and recirculated water into a body of acidic pressurized water to dissolve ozone into the acidic pressurized water. The disclosed methods include simultaneously maintaining a start-up mode in an upper portion of the dissolution column that favors high efficiency of ozone mass transfer into the acidic pressurized water and a steady state mode in a lower portion of the dissolution column that favors a high concentration of dissolved ozone in the acidic pressurized water coexistent in the body of the acidic pressurized water, wherein an ozone concentration gradient is formed along a height of the body of the acidic pressurized water.

First claim

What is claimed is:

1. A method for continuous production of ozone strong water, the method comprising the steps of:
a) injecting an acidification agent into a pressurized feed water stream to maintain a pH value of the pressurized feed water stream below 7;
b) feeding the pressurized feed water stream, after injection of the acidification agent, into a dissolution column to form a body of acidic pressurized water therein;
c) diffusing a two-phase mixture of oxygen-ozone gas and recirculated water into the body of acidic pressurized water in the dissolution column to dissolve ozone into the acidic pressurized water, thereby producing the ozone strong water therein, wherein the recirculated water is an acidic pressurized water stream recirculated from the dissolution column;
d) maintaining a pressure of the dissolution column within a pre-determined pressure range by a controlled release of an off-gas stream from the dissolution column;
e) discharging the ozone strong water from the dissolution column; and
f) adjusting a flow rate of the ozone strong water discharged from the dissolution column to match a flow rate of the pressurized feed water stream fed into the dissolution column after the injection of the acidification agent, so as to simultaneously maintain a start-up mode in an upper portion of the dissolution column that favors high efficiency of ozone mass transfer into the acidic pressurized water and a steady-state in a lower portion of the dissolution column that favors a high concentration of dissolved ozone in the acidic pressurized water coexistent in the body of the acidic pressurized water in the dissolution column,
wherein a concentration gradient of dissolved ozone is formed along a height of the body of the acidic pressurized water.

2. The method of claim 1 , wherein the acidification agent is CO 2 or a mineral acid.

3. The method of claim 1 , wherein the pH value of the body of acidic pressurized water in the dissolution column ranges from 2 to 6.95.

4. The method of claim 1 , wherein the pH value of the body of acidic pressurized water in the dissolution column ranges from 3 to 6.

5. The method of claim 1 , wherein the pre-determined pressure range of the dissolution column is from 2 to 7 barg.

6. The method of claim 1 , wherein a height/diameter ratio of the body of the acidic pressurized water in the dissolution column is larger than 5:1.

7. The method of claim 1 , wherein a residence time of the acidic pressurized water in the dissolution column ranges from approximately 5 minutes to approximately 150 minutes.

8. The method of claim 1 , wherein the pressurized feed water stream is a stream of pressurized fresh water, tap water, process water, effluent water, municipal and industrial wastewater, wastewater already treated by a secondary treatment process.

9. The method of claim 1 , further comprising the step of maintaining a temperature of the body of acidic pressurized liquid within a range of from 10° C. to 30° C.

10. The method of claim 1 , wherein step b) comprises the sub-steps of
b1) feeding the pressurized feed water stream after injection of the acidification agent into a pre-treatment dissolution column to form a body of pre-treatment acidic pressurized water, thereby producing pre-treated ozonated water therein;
b2) pumping the produced pre-treated ozonated water into the dissolution column;
b3) injecting the off-gas stream released from the dissolution column into the body of pre-treatment acidic pressurized water to produce a pre-treated ozonated water in the pre-treatment dissolution column; and
b4) maintaining a pressure of the pre-treatment dissolution column lower than that of the dissolution column through releasing an off-gas stream from the pre-treatment dissolution column.

11. The method of claim 10 , wherein the pH value of the body of the pre-treatment acidic pressurized water in the pre-treatment dissolution column is approximately the same as the pH value of the body of the acidic pressurized water in the dissolution column.

12. The method of claim 10 , wherein a dissolved ozone concentration of the ozone strong water is greater than approximately 150 mg/L.

13. The method of claim 10 , wherein a dissolved ozone concentration of the ozone strong water is approximately 300 mg/L.

14. A method for continuous production of a gas-free liquid containing dissolved ozone, the method comprising the steps of:
a) injecting an acidification agent into a pressurized feed liquid stream to maintain a pH value of the pressurized feed liquid stream below 7;
b) feeding the pressurized feed liquid stream, after injection of the acidification agent, into a dissolution column to form a body of acidic pressurized liquid therein;
c) diffusing a two-phase mixture of oxygen-ozone gas and recirculated liquid into the body of acidic pressurized liquid in the dissolution column to dissolve ozone into the acidic pressurized liquid, thereby producing the gas-free liquid containing dissolved ozone, wherein the recirculated liquid is an acidic pressurized water stream recirculated from the dissolution column;
d) maintaining a pressure of the dissolution column within a pre-determined pressure range by a controlled release of an off-gas stream that contains ozone from the dissolution column;
e) discharging the gas-free liquid containing dissolved ozone from the dissolution column; and
f) adjusting a flow rate of the liquid containing dissolved ozone discharged from the dissolution column to match a flow rate of the pressurized feed liquid stream fed to the dissolution column after injection of the acidification agent, so as to simultaneously maintain a start-up mode in an upper portion of the dissolution column that favors high efficiency of ozone mass transfer into the acidic pressurized liquid and a steady state mode in a lower portion of the dissolution column that favors a high dissolved ozone concentration in the acidic pressurized liquid coexistent in the body of the acidic pressurized liquid in the dissolution column,
wherein a concentration gradient of dissolved ozone is formed along a height of the body of the acidic pressurized liquid.

15. The method of claim 14 , wherein the acidification agent is CO 2 or a mineral acid.

16. The method of claim 14 , wherein the pH value of the body of acidic pressurized liquid in the dissolution column is in a range from 2 to 6.95.

17. The method of claim 14 , wherein the pre-determined pressure range of the dissolution column is from 2 to 7 barg.

18. The method of claim 14 , wherein the gas-free liquid containing dissolved ozone is ozone strong water.

19. The method of claim 14 , wherein the pressurized feed liquid stream is a stream of pressurized fresh water, tap water, process water, effluent water, municipal and industrial wastewater, wastewater already treated by a secondary treatment process, aqueous solutions, or organic solvents.

20. The method of claim 14 , wherein step b) comprises the sub-steps of
b1) feeding the pressurized feed liquid stream, after injection of the acidification agent, to a pre-treatment dissolution column to form a body of pre-treatment acidic pressurized liquid, thereby producing pre-treated ozonated liquid therein;
b2) pumping the produced pre-treated ozonated liquid into the dissolution column;
b3) injecting the off-gas stream that contains ozone released from the dissolution column into the body of pre-treatment acidic pressurized liquid to produce a pre-treated ozonated liquid in the pre-treatment dissolut

Assignees

• Lair Liquide Sa Pour Letude Et Lexploitation Des Procedes George Claude
• Air Liquide American
• Lair Liquide Soc Pour Letude Et Lexploitation Des Procedes Claude

Inventors

• Mante Jan
• Rasanayagam Vasuhi
• Joy Midhun
• Mahmudov Rovshan
• Isazadeh Siavash

Classifications

• B01F35/2113

  Pressure · CPC title

• B01F25/53

  in which the mixture is discharged from and reintroduced into a receptacle through a recirculation tube, into which an additional component is introduced · CPC title

• B01F25/21

  with submerged injectors, e.g. nozzles, for injecting high-pressure jets into a large volume or into mixing chambers · CPC title

• B01F23/70

  Pre-treatment of the materials to be mixed · CPC title

• B01F23/454

  by injecting a mixture of liquid and gas · CPC title