Cold WFI – the new dimension in PHARMACEUTICAL WATER Membrane technology is the future

Werner WFI System 600 l/h: Cold WFI production with hardness stabilizer and 5,000 l storage tank (© Werner GmbH 2018)

An Alternative to Distillation

Since April 2017, the revised European Pharmacopoeia Ph.Eur 9.1/0169 now also permits the "cold membrane process" for the production of WFI alongside traditional distillation in Europe.

Werner GmbH has over 25 years of experience with membrane-based pharmaceutical water systems: In 1992, the first pharmaceutical water system based on RO-EDI ultrafiltration was put into operation, demonstrably meeting WFI criteria. The company has also proven WFI qualities of operators' systems in many other projects for renowned pharmaceutical companies and contract manufacturers, based on cold-stored membrane systems. This experience is now applied to membrane-based WFI production, which has been approved since the Ph. Eur. monograph. A cold WFI system, robust and reliable for the highest microbiological safety. The engineering of cold WFI systems is based on the following stages:

- Pretreatment with hardening stabilizer -> to reduce product-contact surfaces by > 90%
- Use of phosphonic acids instead of polymers -> no AOC increase, no biofouling
- Thermal sanitization at > 80 °C (from drinking water inlet to WFI storage tank)
- Combined UV disinfection/oxidation (254 nm DNA damage / 185 nm TOC reduction)
- Triple barrier against microbiological contamination:
- 2-stage reverse osmosis
- Turbo Clean™ RO membranes (no dead zones between membrane and pressure pipe)
- Ultrafiltration with > log 2 endotoxin reduction
- CEDI system for WFI conductivities < 0.10 µS/cm
- Optional concentrate stage (from 1,000 l/h) to increase system yield up to 90%
- Hot storage > 85 °C or cold storage with permanent ozonation

These production systems are precisely tailored to the requirements of EMA, leveraging the company's extensive experience in membrane technology.