Apparatus and method for minimizing the generation of particles in ultrapure liquids

Abstract

A system and method of reducing particle generation in packaging containers used to transport ultra pure liquids. Particle generation in the containers is reduced by reducing the air-liquid interface present during filling, transport, and dispensing of the liquid.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This is a continuation of U.S. patent application Ser. No. 10 / 139,185, filed on May 3, 2002 in the name of KELLY, Wayne et al. and entitled, “APPARATUS AND METHOD FOR MINIMIZING THE GENERATION OF PARTICLES IN ULTRAPURE LIQUIDS.” The priority of U.S. patent application Ser. No. 10 / 139,185 is claimed under the provisions of 35 USC §120. [0002] The disclosures of the following patent applications are hereby incorporated herein by reference in their respective entireties: U.S. Pat. No. 6,698,619 of Richard Wertenberger, entitled “BAG-IN-DRUM FLUID STORAGE AND DISPENSING CONTAINER HAVING RECTANGULAR PARALLELEPIPED CONFORMATION, AND INTEGRATED FLUID SUPPLY SYSTEM UTILIZING SAME”; and U.S. patent application Publication No. US2003 / 0004608 A1 of Kevin T. O'Dougherty and Robert E. Andrews, entitled “LIQUID HANDLING SYSTEM WITH ELECTRONIC INFORMATION STORAGE.”BACKGROUND OF THE INVENTION [0003] The present invention relates to minimizing the gener...

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Benefits of technology

[0008] The present invention relates to systems and methods of filling containers with ultra pure liquids in a manner that minimizes the amount of particles generated in the liquid. The presence of an air-liquid interface in the container has been shown to increase the particle concentration observed in the liquid. The present invention relates to systems and methods that minimize the air-liquid interface when filling, transporting, and dispensing liquids from containers.

[0009] A first method of reducing particle generation in an ultra pure liquid is to fill containers using a bottom fill method. The bottom fill method is achieved by utilizing a dip tube having a submerged tip from which the liquid enters the container. Submerging the tip of the dip tube below the surface of the liquid during filling of the container allows the liquid to enter the container with reduced splashing, turbulence, and entrainment of air. Avoiding splashing, turbulence, and entrainment of air ensures the air-liquid interface is minimized, and thus reduces the particles generated in the liquid.

[0011] Other methods of reducing particle generation in an ultra pure liquid include submerging the nozzle in a system that uses a nozzle to either fill a container or as a cleaning jet. Submerging the nozzle below the surface of the liquid reduces the air-liquid interface and results in less particle generation.

[0012] In addition, in recirculation baths having a weir over which liquid can fall into a sump, particle generation can occur as the liquid falls into the sump, and causes splashing, bubbles, and turbulence. By reducing the overspill distance between the weir and the liquid in the sump, so that the liquid enters the sump with minimal splashing, reduced particle concentration in the liquid is achieved.

[0013] In siphoning systems, utilizing a smart siphon can also reduce particle concentrations. A smart siphon is one that is controlled to stop the siphoning action before the siphoning action is broken by entrainment of air and causes the remaining liquid in the siphon to fall back into the tank.

[0014] Finally, ensuring that any head space air is removed from the container before shipping reduces the particle concentration in the liquid in the container. In containers using liners, the head-space can be removed from the liner by pressurizing the container and venting out the head space air. In addition, in rigid containers, an inert bladder can be inserted to remove the head-space.

Problems solved by technology

This can in turn render the product deficient or even useless for its intended purpose.

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