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Safe concepts for the cold manufacturing process
In addition to the production of WFI by distillation, we also offer you the generation of WFI by membrane processes: Our systems have two reverse osmosis membrane stages with downstream electrodeionization and ultrafiltration.

Sophisticated concepts: with additional measures for qualification
To ensure the microbial quality, the Letzner system design reduces harmful influences from the outset and integrates numerous preventive measures against microbial growth:

  • Two UV lamps with different wavelengths ensure a reduction of microorganisms and the degradation of nutrients.
  • A high flow rate prevents standing water even in standby phases.
  • A minimized number of exclusively used aseptic connections are an integral part of a sophisticated and robust hygienic design.
  • The design is completely made of AISI 316L grade stainless steel.
  • For the ultrafiltration ozonizable ceramic modules are used in a patented procedure.
  • Different, fully automatic sanitization concepts are available to our customers following EMA requirements.

So you can count on safe product quality even with cold manufacturing processes.

With LETZNER you can rely on a sophisticated plant concept in hygienic design, which successfully restrains microorganisms and endotoxins.

You can find further information on the production of WFI by membrane processes in the data and information pdf.

  • According to all EMA and Ph. Eur. requirements
  • Ozonizable ceramic ultrafiltration with automated integrity test
  • Aseptic connections according to DIN 11864
  • Reynolds numbers > 10,000 even in standby phases
  • Performance regulation: 10-100%

WFI by Membrane Processes


Energy efficient, durable, economical: twin systems for WFI and pure steam
LETZNER offers two procedures for the production of WFI of the highest pharmaceutical quality - production by distillation or by membrane processes. Our distillation plants produce WFI in vaporization columns using the natural circulation procedure. The water is vaporized via heat exchangers in multiple vaporization columns and rises upwards at a slow speed to ensure reliable separation of droplets. WFI results from the condensation of pure steam.

The LETZNER principle for easy maintenance and service
All heat exchangers are situated outside the pressure columns and are designed as DTS (double tube sheet) or simple tube bundle heat exchangers - the LETZNER principle for easy maintenance and service. Depending on the production capacity and for maximum energy efficiency, up to 8 evaporation columns can be connected in series.

Thermal degassing: always standard at LETZNER
When generating WFI by distillation and to comply with EN 285, CO2 and other non-condensable gases are removed by thermal degassing. Thermal degassing is part of the LETZNER anti-rouging concept.

More efficient standby operation: while maintaining full microbiological safety
By lowering the temperature in the pressure columns to > 90 °C, the system is quickly operational again while maintaining microbiological safety. This offers energetic advantages in the operation of the distillation plants as well as lowest possible thermal stresses during heating up, production and cooling down.

Count on a LETZNER system for WFI and pure steam which fully meets your high demands thanks to an energetically sophisticated system design.

You can find further information about the production of WFI by distillation in the data and information pdf.

  • Twin systems for WFI and pure steam production
  • Anti-rouging concept
  • Desalination < 1%
  • Full insulation
  • Natural circulation procedure: no scaling of impurities

WFI by Multi-Effect Pressure Column Distillation