American Sterilizer Company

Conoco Inc.

Arthur L Cummings

Robert W Childers

Alfred E Keller

Fred C Veatch

James C Thompsen

Regina A Severson

William R Miller

David A Karle

Jack H Young

Thaddeus J Mielnik, Jr

Ralph W Makinen

A cation exchange resin is regenerated to remove alkanolamine and alkali metal cations from the resin by eluting the resin with alkali metal hydroxide to selectively displace alkanolamine from the resin, followed by elution of the resin with a mineral acid to displace alkali metal cations and any remaining alkanolamine from the resin. During this process, the resin is monitored by measuring and recording the conductance of the effluent from the resin and such recorded conductance is used to control the regenerant streams to provide more efficient regeneration of the resin.

Monitoring and control system for selective regeneration of alkanolamine

(a) An alkanolamine solution containing anions, a conductance probe connected through a meter to a recorder and a stirrer are provided in a container, (b) the solution is stirred at a constant rate and metering and recording of the conductance of the alkanolamine solution are initiated, (c) an anion exchange resin in the OH.sup.- form is then introduced to the container in an amount in excess of that required to exchange all anions from the amine solution, (d) the conductance of the alkanolamine solution is monitored until steady state is reached, and (e) the total anion content and the sodium content (if present) are determined from the conductance trace. The process and apparatus may be used to display conductance changes with time and rate of conductance changes with time in order to determine which anions are present in the alkanolamine solution, whether or not sodium is present and the magnitude of conductance values at various time intervals.

Process for monitoring alkanolamine solutions

Aqueous alkanolamine solution containing iron sulfide particles is passed through a bed of contact materials having openings greater than the size of the iron sulfide particles and the iron sulfide particles adhere to the contact material. The contact material is regenerated to sequentially remove alkanolamine and iron sulfide particles by contacting it with water.

Removal of iron sulfide particles from alkanolamine solutions

Monitoring and controlling the reactivation of an alkanolamine solution containing heat-stable salts of such alkanolamine with stronger acid anions and weaker acid anions by contacting the alkanolamine solution (a) with a strong base anion exchange resin which has a high affinity for stronger acid anions (b) contacting the effluent alkanolamine solution from the strong base anion exchange resin with a second strong base anion exchange resin which has an affinity for weaker acid anions (c) measuring and recording the electrical conductance of the effluent solution from the first mentioned anion exchange resin (d) removing the first mentioned anion exchange resin from service when the conductance of the effluent alkanolamine solution from said resin indicates breakthrough of stronger acid anions in said effluent, (e) measuring and recording the electrical conductance of the effluent alkanolamine solution from the second mentioned anion exchange resin (f) removing the second mentioned anion exchange resin from service when the conductance of the effluent alkanolamine solution from said resin indicates break through of weaker acid anions in said effluent and (g) regenerating the strong base anion exchange resins.

Process for monitoring and controlling an alkanolamine reaction process

A sterilization method including the steps of injecting a hydrogen peroxide and water vapor mixture into a closed sterilization chamber of a predetermined volume at a predetermined temperature in an initial amount up to the saturation limit of such vapor mixture and thereafter, injecting a plurality of intermittent make-up injections of such vapor mixture into the chamber. The rate of the make-up injections and the amount of each such make-up injection is based on the rate and amounts necessary to maintain the concentration of hydrogen peroxide vapor at a level effective for sterilization but less than that which would raise the concentration of the vapor mixture to the saturation limit which will be present in the chamber immediately following injection of a make-up injection.

Optimum hydrogen peroxide vapor sterilization method

This process sterilizes the surfaces within a chamber wherein a first portion of the surfaces is at a temperature below 10.degree. C. and a second portion of the surfaces is at a temperature greater than 20.degree. C. The process includes the steps of introducing vapor phase hydrogen peroxide to the chamber, contacting the first portion with the vapor to effect condensation thereon, contacting the second portion with the vapor, applying a source of vacuum to the chamber and continuing to introduce vapor phase hydrogen peroxide into the chamber until the surfaces are sterile while preserving the temperature ranges of the first and second portions.

Hydrogen peroxide sterilization method

The present invention provides a flow-through system for use with at least one sealable pressure or nonpressure container. The system can be used to selectively sterilize, humidify and aerate the container and can be integrally or releasably attached to the container. The system includes at least one liquid reservoir for holding a sterilant, such as an aqueous solution of hydrogen peroxide. A second liquid reservoir for holding water for humidification may be provided. The system also includes a unit which houses a heater for vaporizing incoming liquid and optionally heating incoming air and a converter for converting selected vapors to a form suitable for disposal. A vacuum motor draws air from the container to reduce pressure therein so that air from an air supply is drawn through an air filter into the heater and into the container. A substantial portion of the withdrawn air from the container is diverted to the converter. The reduced pressure in the container may be sufficient for urging liquid from the reservoir to the heater where the liquid is vaporized and carried by the stream of air into the container. Alternatively, a remaining portion of withdrawn air may be used to exert pressure within the liquid reservoir to urge the liquid to the heater. Valves are provided to selectively control liquid flow to the heater.

Flow-through vapor phase sterilization system

A system is provided for determining the concentration of a condensable vapor in the presence of at least one other condensable vapor, such as hydrogen peroxide and water vapors. The system includes generally a dew point sensor, a device for measuring at least one additional property of at least the other vapor such as relative humidity, and a microprocessor for fitting the dew point and additional property measurements into a modeled construct representative of the relationship between the vapors at a plurality of concentrations for each such vapor and at a plurality of corresponding dew point measurements. When used to determine the concentration of sterilant vapor in a sterilization system, the system also includes a sterilization chamber and an injector for injecting a measured quantity of the multicomponent condensable vapor into the chamber.

System for monitoring sterilant vapor concentration

A process for concentrating hydrogen peroxide from a relatively dilute solution of hydrogen peroxide and water and supplying the concentrated hydrogen peroxide in vapor form to a sterilization chamber. The process includes vaporizing a major portion of the water from the solution and removing the water vapor thereby produced before injecting the concentrated hydrogen peroxide vapor into the sterilizing chamber.

Vaporization method to enhance sterilant penetration

An improvement in a process for sterilizing goods comprising a method for substantially reducing condensate on the processed goods. The method includes producing an exothermic reaction during the process between effective amounts of at least two reactants to release at least a sufficient quantity of heat proximate the goods to substantially reduce condensate on the goods at the conclusion of the process. Hydratable salts may be housed in a liner which is permeable to a condensate vapor present in the process. Contact between the vapor, or condensate, and the salt produces the exothermic reaction during the process.

Growing community of inventors

Ponca City, OK, United States of America

Arthur L Cummings