Methods and systems for detecting and quantifying peroxy acid and peroxide in fluids

Patent metadata

Field	Value
Publication number	US-10989699-B2
Application number	US-201715653895-A
Country	US
Kind code	B2
Filing date	Jul 19, 2017
Priority date	Jul 19, 2016
Publication date	Apr 27, 2021
Grant date	Apr 27, 2021

Abstract

Methods and systems are disclosed for analyzing and treating a fluid containing a peroxyacid and/or peroxide. A method of analyzing the fluid includes introducing into the fluid a decomposition agent that catalyzes decomposition of the peroxyacid and/or peroxide into decomposition products including oxygen, then directly or indirectly measuring an amount of oxygen produced after introduction of the decomposition agent, and determining an amount of the peroxyacid and/or peroxide present in the fluid. The amount of peroxyacid and/or peroxide in the fluid can also be monitored and controlled by further adjusting the amount of the peroxyacid and/or peroxide in the fluid based on the determined amount thereof. A system for performing the methods includes a decomposition agent infusion device for introducing the decomposition agent into a fluid sample, and a sensor for directly or indirectly measuring an amount of oxygen produced after introduction of the decomposition agent.

First claim

What is claimed is:

1. A method of analyzing a fluid that includes at least one of peroxyacid and peroxide, the method comprising:
introducing into the fluid a decomposition agent that decomposes the peroxyacid and/or peroxide into decomposition products;
directly measuring an amount of dissolved oxygen that is produced in the fluid as one of the decomposition products resulting from the decomposition of the peroxyacid and/or peroxide by the decomposition agent; and
then determining an amount of the peroxyacid present in the fluid based on the measured amount of the dissolved oxygen.

2. The method according to claim 1 , further comprising directly measuring an amount of dissolved oxygen in the fluid before introducing the decomposition agent into the fluid.

3. The method according to claim 1 , wherein the fluid has been treated such that it is substantially free of peroxide and is in a gaseous phase before the introduction of the decomposition agent.

4. The method according to claim 3 , wherein, in the measuring step, the amount of the dissolved oxygen is directly measured in the gaseous fluid.

5. The method according to claim 1 , wherein the peroxyacid is peracetic acid.

6. The method according to claim 1 , wherein the decomposition agent is selected from the group consisting of catalase, sodium hypochlorite, metal catalyst, alkaline solution, haloamine, and ultraviolet light.

7. The method according to claim 1 , further comprising adjusting the pH of the fluid to be in a range of from 6.5 to 11.5.

8. The method according to claim 1 , wherein the measuring step is performed after partial decomposition of the peroxyacid and/or peroxide in the fluid.

9. A method of monitoring and controlling an amount of peroxyacid in a fluid, the method comprising:
introducing into a sample of the fluid a decomposition agent that decomposes the peroxyacid and/or peroxide into decomposition products;
directly measuring an amount of dissolved oxygen that is produced in the fluid as one of the decomposition products resulting from the decomposition of the peroxyacid and/or peroxide by the decomposition agent;
then determining an amount of the peroxyacid present in the fluid based on the measured amount of the dissolved oxygen; and
adjusting the amount of the peroxyacid in the fluid based on the determined amount thereof.

10. The method according to claim 9 , wherein, in the adjusting step, the amount of the peroxyacid in the fluid is adjusted to be within a predetermined range.

11. The method according to claim 9 , wherein, in the adjusting step, the amount of the peroxyacid in the fluid is adjusted by:
adding more of the peroxyacid into the fluid to increase the amount thereof in the fluid, or
introducing a neutralization agent into the fluid to decrease the amount of the peroxyacid in the fluid.

12. The method according to claim 11 , wherein the neutralizing agent is selected from the group consisting of bisulfite, erythorbate, cerium (III), catalase, sodium hypochlorite, metal catalyst, alkaline solution, haloamine, and ultraviolet light.

13. A system for analyzing and treating a fluid containing at least one of peroxyacid and peroxide, the system comprising:
a sample collector configured to collect a sample of the fluid;
a decomposition agent infusion device configured to introduce into the sample a decomposition agent that decomposes the peroxyacid and/or peroxide into decomposition products;
a sensor configured to directly measure an amount of dissolved oxygen that is produced in the fluid as one of the decomposition products resulting from the decomposition of the peroxyacid and/or peroxide by the decomposition agent; and
a controller configured to determine an amount of the peroxyacid in the fluid based on the measured amount of the dissolved oxygen by the sensor.

14. The system according to claim 13 , wherein the controller is further configured to control the amount of peroxyacid, or an amount of a neutralization agent that is introduced into the fluid based on the determined amount of the peroxyacid in the fluid.

15. The system according to claim 13 , further comprising a neutralization agent infusion device configured to introduce a neutralization agent into the fluid.

16. The method according to claim 1 , wherein:
the decomposition agent decomposes peroxide and not peroxyacid; and
the amount of peroxyacid is determined based on the measured amount of the dissolved oxygen produced from the decomposition of peroxide.

17. The method according to claim 1 , wherein the amount of the dissolved oxygen is directly measured by a sensor.

Assignees

• Chemtreat Inc

Inventors

• Richardson John
• Puchovich Mark
• Niemaseck Benjamin
• White Kevin
• Wilkins James
• Bedinger Robert

Classifications

• B01L2300/0627

  Sensor or part of a sensor is integrated · CPC title

• C12Q1/30

  involving catalase · CPC title

• G01N31/225

  for oxygen, e.g. including dissolved oxygen · CPC title

• C12Y111/01006 Primary

  Catalase (1.11.1.6) · CPC title

• G01N31/228 Primary

  for peroxides · CPC title