Method for recycling sterilant gas

• US 7,910,055 B2
• Filed: 12/14/2009
• Issued: 03/22/2011
• Est. Priority Date: 09/29/2006
• Status: Active Grant

• Current Assignee: Kpr U.S., LLC (Cardinal Health, Inc.)
• Original Assignee: Tyco Healthcare Group LP (Medtronic Plc)
• Inventors: Bondar, Douglas E.
• Primary Examiner(s): CONLEY, SEAN EVERETT
• Application Number:
  US12/637,087
• Publication Number:
  US 20100092336A1
• Time in Patent Office: 463 Days
• Field of Search: 422/3, 422/28, 422/31, 422/110, 422/292
• US Class Current: 422/31
• CPC Class Codes: A61L 2/206 Ethylene oxide

Abstract

A system for recovery and reutilization of sterilant gas mixture from a sterilizer chamber includes a storage tank in gaseous communication with a sterilizer chamber via a gas recovery assembly, wherein after sterilization the gas recovery assembly evacuates the sterilant gas mixture to the storage recovery tank. The system also includes an inert purge gas supply adapted to supply a purge gas to the sterilizer chamber after the sterilant gas mixture is withdrawn to the storage recovery tank, wherein the gas recovery assembly evacuates an additional portion of the purge gas from the sterilizer chamber to the storage tank to enrich the gas mixture for later reutilization in subsequent sterilization cycles.

Claims

1. A method for recovery of a sterilant gas mixture from a sterilizer chamber, comprising:

withdrawing a sterilant gas mixture after sterilization from a sterilizer chamber via a gas recovery assembly to a storage tank such that the pressure of the sterilant gas mixture is lowered;

supplying a purge gas to the sterilizer chamber after the sterilant gas mixture is withdrawn to the storage tank; and

withdrawing the purge gas from the sterilizer chamber to the storage tank to form a combined mixture of the sterilant gas mixture and the purge gas.

2. A method according to claim 1, wherein the storage tank has a volume higher than a volume of the sterilizer chamber and wherein, during the step of withdrawing the sterilant gas mixture, the storage tank is adapted to store the sterilant gas mixture at pressure lower than the atmospheric pressure.

3. A method according to claim 1, wherein the purge gas is an inert gas and wherein during the step of withdrawing the purge gas, the inert gas is withdrawn from the sterilizer chamber to the storage tank to form a combined mixture of the sterilant gas mixture and the inert gas.

4. A method according to claim 1, further comprising:

evacuating the storage tank prior to withdrawing the sterilant gas mixture from the sterilizer chamber.

5. A method according to claim 1, wherein supplying the purge gas further includes supplying the purge gas to the sterilizer chamber to pressurize the sterilizer chamber at a pressure lower than atmospheric pressure.

6. A method according to claim 1, further comprising:

pressurizing the sterilizer chamber at atmospheric pressure after the purge gas is withdrawn from the sterilizer chamber to the storage tank.

7. A method according to claim 1, wherein the purge gas is an inert gas and wherein while withdrawing the purge gas, the inert gas is withdrawn from the sterilizer chamber to the storage tank to form a combined mixture of the sterilant gas mixture and the inert gas.

8. A method for recovery of a sterilant gas mixture from a sterilizer chamber, comprising:

withdrawing a sterilant gas mixture after sterilization from a sterilizer chamber via a gas recovery assembly to a storage tank such that the pressure of the sterilant gas mixture is lowered;

supplying a purge gas to the sterilizer chamber after the sterilant gas mixture is withdrawn to the storage tank;

withdrawing the purge gas from the sterilizer chamber to the storage tank to form a combined mixture of the sterilant gas mixture and the purge gas; and

supplying the combined mixture of the sterilant gas mixture and the purge gas to the sterilizer chamber.

9. A method according to claim 8, wherein the storage tank has a volume higher than a volume of the sterilizer chamber, and wherein while withdrawing the sterilant gas mixture, the storage tank is adapted to store the sterilant gas mixture at pressure lower than atmospheric pressure.

10. A method according to claim 8, wherein the purge gas is an inert gas and wherein while withdrawing the purge gas, the inert gas is withdrawn from the sterilizer chamber to the storage tank to form a mixture of the sterilant gas mixture and the inert gas.

11. A method according to claim 8, further comprising the step of:

evacuating the storage tank prior to withdrawing the sterilant gas mixture from the sterilizer chamber.

12. A method according to claim 8, wherein the step of supplying the purge gas further includes supplying the purge gas to the sterilizer chamber to pressurize the sterilizer chamber at a pressure lower than atmospheric pressure.

13. A method according to claim 8, further comprising the step of:

pressurizing the sterilizer chamber at atmospheric pressure after the purge gas is withdrawn from the sterilizer chamber to the storage tank.

14. A method according to claim 8, wherein the step of withdrawing the purge gas from the sterilizer chamber further includes storing the combined mixture of the sterilant gas mixture and the purge gas at atmospheric pressure within the storage tank.

15. A method for recovery of a sterilant gas mixture from a sterilizer chamber, comprising:

withdrawing a sterilant gas mixture after sterilization from a sterilizer chamber via a gas recovery assembly to a storage tank such that the pressure of the sterilant gas mixture is lowered;

supplying a purge gas to the sterilizer chamber after the sterilant gas mixture is withdrawn to the storage tank;

withdrawing the purge gas from the sterilizer chamber to the storage tank to form a combined mixture of the sterilant gas mixture and the purge gas;

supplying the combined mixture of the sterilant gas mixture and the purge gas to the sterilizer chamber;

determining an amount of at least one of the sterilant gas mixture and the purge gas present in the combined mixture; and

refortifying the combined mixture with at least one of the sterilant gas mixture and the purge gas based on the determined amount in the combined mixture.

16. A method according to claim 15, wherein the storage tank has a volume higher than a volume of the sterilizer chamber, and wherein while withdrawing the sterilant gas mixture, the storage tank is adapted to store the sterilant gas mixture at a pressure lower than atmospheric pressure.

17. A method according to claim 15, wherein the purge gas is an inert gas and wherein while withdrawing the purge gas, the inert gas is withdrawn from the sterilizer chamber to the storage tank to form a combined mixture of the sterilant gas mixture and the inert gas.

18. A method according to claim 15, further comprising:

evacuating the storage tank prior to withdrawing the sterilant gas mixture from the sterilizer chamber.

19. A method according to claim 15, wherein supplying the purge gas further includes supplying the purge gas to the sterilizer chamber to pressurize the sterilizer chamber at a pressure lower than atmospheric pressure.

20. A method according to claim 15, further comprising:

pressurizing the sterilizer chamber at atmospheric pressure after the purge gas is withdrawn from the sterilizer chamber to the storage tank.

21. A method according to claim 15, wherein withdrawing the purge gas from the sterilizer chamber further includes storing the combined mixture of the sterilant gas mixture and the purge gas at atmospheric pressure within the storage tank.