Bosch Packaging Technology has developed a new generation of pure steam generators and distillation units for the production of sterile, pyrogen-free pure steam or WFI (water for injection) offering optimised performance and energy efficiency.
WFI is predominantly needed for the production of infusion and injection solutions, while pure steam is mainly used for sterilising equipment components such as preparation vessels, piping systems and filling machines. In addition, pure steam is employed for the humidification of air in cleanrooms.
Bosch delivers the new distillation units with a preheater. From the second column onwards, it uses pure steam from the previous column to preheat the feed water. As a result, heating energy demand is significantly reduced. For pure steam generators, a preheater is available as an option, which is fed with condensate from the heating steam. Using this stored energy reduces heating steam consumption.
The equipment’s evaporator operates according to the natural circulation principle. The water, which is fed for evaporation, continually circulates between the evaporation chamber and the heat exchanger. A high thermal transfer enables the system to be heated up smoothly without causing temperature stress for the evaporator. This process only needs electrical energy or heating steam; no further process steps or functional modules such as a compressor are required.
'The new, compact design of the evaporator contributes to optimal thermal use of heating energy, leading to high yields and low operating costs,' said Dr John Medina, Sales Director at Bosch subsidiary Pharmatec.
'Since the production of pure steam and WFI is particularly energy-intensive, improvements in efficiency play an important role in sustainability and climate protection.'
The geometry of both evaporators and condensers has been optimised for the new product range, with Bosch adjusting the evaporator’s diameter as well as the number and formation of the heating pipes. Subsequently, the machines can achieve 20% higher performance rates compared with previous models.
Bosch has also reduced the amount of water loss, which results from the disposal of endotoxins (blowdown) in the feed water, from between 5–8 to no more than 4%.
These new developments have allowed Bosch to streamline its product range, reducing the number of different sizes from 11 to six pure steam generators and from 14 to ten distillation units.
The series now encompasses a performance range of 100 to 7,500kg/hour and to enable quick set-up, feed water pumps with frequency regulation are used for all sizes.