In addition to WFI and USP purified water, in Europe there is a third class of water called “highly purified water, like a super grade of USP,” points out Chris Fournier, vp of marketing at Mar Cor Purification (www.marcorpurification.com). It can be used for preliminary rinsing and cleaning steps, for example, thereby reducing the size of the WFI system needed.
Unlike WFI, which is traditionally produced with a still, highly purified water is not boiled. Instead, it goes through various pretreatment steps, one or two RO passes, a deionization step, and sometimes ultraviolet radiation and a final filtration step. The end result is highly purified water that is equivalent to WFI but produced at a lower cost.
The RODI-HPW (RO/electrodeionization systems are Mar Cor’s highest quality water treatment systems for producing a highly purified grade of water. The company also offers single- and two-pass RO systems, hot water sanitizable RO and EDI systems, service deionization systems, and electrodeionization systems.
In sync with efforts to use USP-purified water more selectively, particularly in earlier phases of CIP, some companies are using softened water for the prerinse and chemical cleaning cycles, according to Steve Orichowskyj, engineering team leader at Alfa Laval Biokinetics. The advantages of this approach are savings in production costs, less water waste, and lower maintenance, validation, and testing costs.
“Every site has its own needs, experience, and bias,” says Greg Hoyt, senior bioprocess specialist at Alfa Laval. Customers also have different comfort levels with change. “A lot of customers are hesitant to use softened water,” he adds, especially if they are producing a high-value product. The use of softened water may be a more attractive option for companies with large-scale manufacturing operations, in which cost factors are more closely linked to commercial success.
“In the pharmaceutical market, I see an increasing use of ozone for sanitization of distribution loops,” says Fournier. He describes the use of low levels of ozone as a viable replacement for heat sanitization, which carries high energy costs, or for chemical sanitization methods, which require disposal of chemical waste down the drain and the need for copious amounts of high purity rinse water as key concerns. Ozone naturally breaks down in a short period of time and is destroyed when exposed to ultraviolet light, facilitating its removal from the distribution system.