Kerry system cleans up Portex costs

Kerry Ultrasonics says the move by Portex to a mono-solvent cleaning system has enabled the UK-based medical device manufacturer to reduce solvent consumption by 85%.

For environmental reasons, Portex was obliged to move away from solvent 141b, but was concerned about the significant increase in cleaning costs which might be incurred. Kerry estimates that had Portex retained its machine, which ran on HCFC 141b, the difference in price between the old solvent and the HFE 72DE that replaced it would have seen the company's cleaning expenditure increase sixfold. However, by using just 15% of the amount of solvent consumed by Portex's former system, Kerry's new cleaning plant, a Microsolve 250 mono-solvent system, has avoided any increase in solvent outlay. The new system removes silicone oil from nasal intubation tubes. Approximately 200mm long and 10mm in diameter, the PVC tubes must be free of all traces of silicone oil if they are to be successfully printed with ink. The cleaning process is carried out in a cleanroom and comprises three stages. An ultrasonic clean in sump 1 with closed-loop filtration, using 3M's environmentally- and operator-safe Novec HFE 72DE, is followed by a vapour rinse, the vapour being produced by boiling solvent in sump 2. Finally, tubes dwell in the freeboard area to dry where the HFE condenses onto the refrigerated cooling coils to return via a water separator to sump 1. Contaminated solvent is then displaced into the boiling sump. This distillation, together with filtration of the solvent, ensures the ultrasonic tank is maintained at a controlled level of cleanliness and the tubes are free of solvent. The Microsolve unit is automated with an Autotrans SA (Single Axis) lift, which Kerry says significantly reduces operator time and therefore product cost and also ensures low solvent consumption due to minimal drag-out.