Twin-Screw-Pump Receives EHEDG EL Aseptic Certificate

Single-flow hygienic Twin-Screw-Pumps, type SLH from ITT Bornemann, have been successfully installed in many applications in the food-, beverage and pharmaceutical industry for more than 20 years.

It is one of the main functions to pump high viscous fluids. Because of the high rotational speed range (up to 3600 rpm) it is also possible for the pump to handle low viscous products with a high flow velocity. So it is possible to use the SLH Twin-Screw-Pumps also for the CIP-Process. Further reasons for the success of SLH-Twin-Screw-Pumps are the less pulsation, the high suction capability and the smooth handling of the fluid.

Another big advantage becomes more and more important: the hygienic design.

To reach this high hygienic criteria ITT Bornemann designs the pump inside and outside in best way without loss of functionality. As a result the pump is EHEDG EL class 1 certified and also 3-A registered. Now ITT Bornemann SLH-4G Twin-Screw-Pump reaches the next level: EHEDG EL Aseptic Certificate.

This type of certification is intended for single components which are suitable for aseptic applications. Aseptic processes require three main issues, i.e. cleanability in place (CIP), sterilisability and bacteria tightness, which have to be fulfilled to get the certification on Type EL Aseptic. For cleanability, certificate Type EL - Class I has to be achieved and in addition the tests on sterilisability and bacteria tightness have to be passed. So as ITT Bornemann SLH-4G Twin-Screw-Pump already passed the cleanability test, the pump only needed to be tested in bacteria tightness and sterilisability. No other positive displacement pump is certified with this Aseptic certificate.

EHEDG sterilisability test

This verification attests the SLH-4G Twin-Screw-Pump the “Inline-Steam-Sterilisability”. The test unit is contaminated with an indicated micro-organism. Afterwards the test unit is sterilized with steam for 30 minutes at 121°C. To detect still surviving spores after sterilization, a culture medium is pumped to the test unit by five days. If the nutrient solution after this 5-day incubation is cloudy not all spores were killed by the sterilization. If the bouillon is clear the component can be classified as sterilized. This test is done 3-times. A zero and a reference sample are taken. The blank sample must remain clear and the reference sample with the microorganisms must become cloudy.

The results of the EHEDG sterilisability test show that the product-wetted surfaces of the SLH-4G Twin-Screw-Pump can be sterilized with steam and so sterilization according to EHEDG exists.

The SLH-4G is “Inline-Steam-Sterilisability”