Dec 28, 2000

Precision Tubing Ensures Purity of Water Filtration System

In today’s laboratory environment, it is essential that pure water is available for numerous applications. If contaminated water comes into contact with certain materials, it will draw out impurities from that material and adversely affect the purity of the water produced.

Barnstead/Thermolyne, in conjunction with Lab-Line and Electrothermal, has taken a total system approach in producing pure water for laboratories and gauging its impact on the entire water filtration system.

An important state of Barnstead/Thermolyne’s purification process is the removal of both organics and chlorine from the water. Traditionally, carbon has been used to remove these elements. If they are not completely removed, the ion exchange resins that follow could become irreparably contaminated. Properly using the various types of carbon enhances the ability to produce water containing less than two ppb of total organic carbons.

Following this removal, at least two mixed bed cartridges housed with extruded polypropylene tubing are used to ensure total elimination of all interference. For this reason, it is mandatory that the tubes be derived from the most pristine plastic available.

"The cartridge tubes are an important component of the new Nanopure Diamond and are presently being used for existing systems, including Nanopure Infinity, Nanopure, Nanopure II and E-Pure," said Jim Hickie, purchasing manager at Barnstead/ Thermolyne. "These all are ultrapure water systems."

TEEL Plastics, Inc., located in Baraboo, Wis., was selected by Barnstead/Thermolyne to provide the extruded plastic tubing for the cartridges. As part of the quality control equation, TEEL tubing can be customized in terms of outside and inside diameter tolerances as well as meeting precise length requirements. This type of specification ensures the purity of all existing water that is used for some of the most demanding applications (e.g., gas and high-performance chromatography) found in laboratories.

At the same time, Hickie concluded that it is the responsibility of both the manufacturers as well as the end users to ensure that the cartridges are configured properly within the system. If the tehnologies are not utilized properly, the purity of the water is compromised and will limit its usefulness for a demanding application.

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