US-12622989-B2 - System and method for sterilization of objects

US12622989B2US 12622989 B2US12622989 B2US 12622989B2US-12622989-B2

Abstract

The present subject matter relates to a system and a method for producing Hydrogen Peroxide in situ for sterilization of objects. In the system and the method, Hydrogen Peroxide solution of 30-35% concentration is processed to reach a target concentration value in a range of 90-95% of the resulting concentrated Hydrogen Peroxide.

Inventors

M. Nageswara Rao

Assignees

PHARMALAB INDIA PVT. LTD.

Dates

Publication Date: 20260512
Application Date: 20240604
Priority Date: 20220207

Claims (10)

1 . A system for producing Hydrogen Peroxide in situ for sterilization of objects, the system comprising: a pumping unit, at a first end of the system, to supply a Hydrogen Peroxide solution of 30-35% concentration at a prespecified pressure and a prespecified rate; a vaporizing unit, fluidically connected to the pumping unit, to receive the Hydrogen Peroxide solution and vaporize the pressurized Hydrogen Peroxide solution; a vacuum pump fluidically connected at a second end of the system thereby generating a negative vacuum pressure between the vaporizing unit and the vacuum pump, a drying unit, fluidically connected between the vaporizing unit and the vacuum pump to perform a dry purging procedure on the vaporized Hydrogen Peroxide solution, the drying unit comprising: a fifth inlet connected to the vaporizing unit to receive the vaporized Hydrogen Peroxide solution, an inner membrane tube defining a first flow path for the vaporized Hydrogen Peroxide solution, an annular purge-gas passage surrounding the inner membrane tube the annular passage having: a purge-gas inlet disposed distal to the fifth inlet to receive a dry purge gas, and a purge-gas outlet disposed proximal to the fifth inlet to discharge a wet purge gas, wherein, at least under the effect of the negative vacuum pressure generated by the vacuum pump, the inner membrane tube is to cause water vapor to diffuse therethrough into the annular passage while vaporized Hydrogen-Peroxide is retained within the inner membrane tube; and a fifth outlet fluidically connecting the drying unit to the vacuum chamber to output concentrated Hydrogen Peroxide vapors substantially devoid of water vapor from the inner membrane tube; and a vacuum chamber, fluidically connected between the drying unit and the vacuum pump, to receive the concentrated Hydrogen Peroxide vapors for the sterilization of the objects, wherein the vacuum pump is to cause movement of the Hydrogen Peroxide vapors at least from the vaporizing unit to the vacuum chamber, and wherein the system further comprises a degasser that removes the dissolved gases from the Hydrogen Peroxide solution by applying vacuum to a semi-permeable membrane, the degasser is fluidically connected between the pumping unit and the vacuum pump such that the Hydrogen Peroxide vapors received at the vacuum chamber are substantially devoid of gases, wherein the Hydrogen Peroxide is generated in situ.
2 . The system as claimed in claim 1 , wherein the system comprises a control unit connected to the pumping unit, the vaporizing unit, and the drying unit, wherein the control unit is to: regulate the pumping unit to supply the Hydrogen Peroxide solution at the prespecified pressure and the prespecified rate; regulate the vaporizing unit to vaporize an aqueous content of the Hydrogen Peroxide solution into water vapours; and regulate the drying unit to perform the dry purging procedure on the vaporized Hydrogen Peroxide solution to obtain the concentrated Hydrogen Peroxide vapors substantially devoid of water vapor.
3 . The system as claimed in claim 2 , wherein the system comprises an ultraviolet lamp disposed inside the vacuum chamber, wherein the ultraviolet lamp is to emit ultraviolet radiations for drying water films deposited on inner surfaces of the vacuum chamber, for sterilizing cavities of the objects where the Hydrogen Peroxide is not reachable, and for breaking the residual molecules of the Hydrogen Peroxide, which are not broken by vacuum inside the vacuum chamber.
4 . The system as claimed in claim 1 , wherein the pumping unit is a solenoid driven diaphragm pump.
5 . The system as claimed in claim 1 , wherein the system comprises a filter disposed between the pumping unit and the drying unit for separating impurities from the Hydrogen Peroxide solution.
6 . The system as claimed in claim 1 , wherein the system comprises a diffuser between the pumping unit and the vaporizing unit to diffuse the pressurized Hydrogen Peroxide solution received from the pumping unit.
7 . The system as claimed in claim 6 , wherein the system comprises a nozzle disposed between the diffuser and the vaporizing unit to generate an atomized spray of the Hydrogen Peroxide solution having a uniform droplet size.
8 . The system as claimed in claim 7 , wherein the nozzle is one of a misting nozzle and an ultrasonic nozzle.
9 . The system as claimed in claim 3 , wherein the inner surfaces of the vacuum chamber have a surface finish of 0.4 micrometers.
10 . The system as claimed in claim 1 , wherein the fluidic connection between the vacuum pump and the vaporizing unit is controlled by a piezoelectric valve.

Description

PRIORITY CLAIM TO RELATED APPLICATIONS This application is a continuation of International Application No. PCT/IN2022/050510, filed on 1 Jun. 2022, and published as WO2023/148750 on 10 Aug. 2023, which claims the benefit under 35 U.S.C. 119 to India application Ser. No. 202221006538, filed on 7 Feb. 2022, the benefit of priority of each of which is claimed herein, and which applications and publication are hereby incorporated herein by reference in their entirety. BACKGROUND In general, re-usable medical devices such as certain surgical instruments, endoscopes, etc., may be sterilized with a principal sterilizing agent to destroy or eliminate all forms of microbial life before re-use in order to minimize the likelihood that a contaminated device might be used on a patient, which could cause an infection in the patient. BRIEF DESCRIPTION OF THE DRAWINGS The following detailed description references the drawings, wherein: FIG. 1 shows a block diagram of a system for producing Hydrogen Peroxide in situ for sterilization of objects, according to an example; FIG. 2 shows a schematic diagram of a drying unit, according to an example; and FIG. 3 shows a flow diagram of a method for producing Hydrogen Peroxide in situ for sterilization of objects, according to an example. DETAILED DESCRIPTION Re-usable medical devices such as certain surgical instruments, may be sterilized using a vaporised hydrogen peroxide sterilization. The vaporised hydrogen peroxide sterilization is a low temperature sterilization generally used to sterilize heat-sensitive devices, such as medical devices. The sterilization is done before re-use to ensure that a contaminated device is not used on a patient. In the hydrogen peroxide sterilization, vapor of hydrogen peroxide is filled in a sterilizing chamber, where the medical devices to be sterilized are placed. Further, exposed surfaces of the medical devices contact the vapors of the hydrogen peroxide for the sterilization. After completing the hydrogen peroxide sterilization, the vapors are evacuated from the sterilizing chamber and converted to water and oxygen molecules. Liquid hydrogen peroxide is flammable and can explode in case of any accident during the transportation from one location to another. Handling of highly concentrated liquid hydrogen peroxide is hazardous and cause injuries if the highly concentrated liquid hydrogen peroxide comes in contact with humans or animals. Therefore, highly concentrated hydrogen peroxide is not possible to be transported and handled directly for use in the sterilization processes. Commonly, for the hydrogen peroxide sterilization, the hydrogen peroxide used is an aqueous solution having a concentration of 30-35% of the hydrogen peroxide. However, use of such a low concentration of 30-35% of the hydrogen peroxide results in high consumption of the hydrogen peroxide solution. Also, the duration of the hydrogen peroxide sterilization with such a concentration of the hydrogen peroxide solution may take several hours. The present subject matter describes example systems and methods for producing Hydrogen Peroxide in situ for sterilization of objects. In the example systems and methods described herein, ultra-pure vapor of hydrogen peroxide of high concentration can be obtained. To perform a hydrogen peroxide sterilization of an object, particularly, a medical device, the object is placed inside a vacuum chamber. In an example, the medical device may be a scalpel, a flow probe, an endoscope, etc. In an example, multiple medical devices may be placed inside the vacuum chamber. After placing the object inside the vacuum chamber, a pumping unit supplies a Hydrogen Peroxide solution of 30-35% concentration at a prespecified pressure and a prespecified rate to a vaporizing unit, which is connected to the pumping unit. Further, aqueous content of the pressurized Hydrogen Peroxide solution is vaporized to fine water vapors by the vaporizing unit. The fine water vapors of the Hydrogen Peroxide solution flow to a drying unit connected to the vaporizing unit. The fine water vapors enable convenient flow to the Hydrogen Peroxide solution without blocking the path. Further, a purging procedure is performed on the vaporized Hydrogen Peroxide solution. The purging procedure is performed by the drying unit to extract water vapors from the vaporized Hydrogen Peroxide solution. The drying unit is connected to the vaporizing unit. The water vapors are extracted until the resulting concentrated Hydrogen Peroxide have reached a target concentration value in a range of 90-95%. The concentrated Hydrogen Peroxide having the target concentration value in the range of 90-95% is received by the vacuum chamber, in which the objects to be sterilized are placed, for the sterilizing the objects. Further, the pumping unit, the vaporizing unit, and the drying unit are connected to a control unit, which regulates each of the pumping unit, the vaporizing unit, and the drying unit. In an