LEONI Studer Hard, Pioneering X-ray Sterilization
LOUVAIN-LA-NEUVE, Belgium, March 15, 2012 /PRNewswire/ --
LEONI Studer Hard AG is located in Däniken (Switzerland) and offers sterilization, decontamination and crosslinking services to third parties. LEONI Studer Hard AG is a well known and established European player, experienced in E-beam, gamma and X-ray Irradiation technologies.
Why X-ray Sterilization?
Up till 2011, LEONI Studer Hard proposed two sterilization services based on two technologies: gamma pallet sterilization and E-beam (box) sterilization.
The decision to use gamma or E-beam sterilization is mainly based on the treatment Dose Uniformity Ratio (DUR) requirement. For small packages of products with limited density, E-beam is the preferred technology since faster processing and more efficient. But for other products packaged on pallets, too dense or with non-homogenous density, E-beam could not make it and gamma was required to achieve target DUR.
Managing a gamma facility is increasingly complex. Regulations are stricter in terms of workers safety and Co-60 transportation, the price of Co-60 is steadily increasing year by year and the local authorities are very uncomfortable with radioisotope based facilities.
On the other hand, customers are requesting more and more pallet sterilization services, with a very uniform distribution of the sterilization dose… which cannot always be done with E-beam.
All these reasons initiated LEONI Studer Hard's reflection of potentially using X-ray as an alternative to gamma sterilization.
The expectations towards X-ray were:
- Become much less dependent on cobalt-60, because of X-rays' ability to adjust power immediately, depending on workload.
- Limiting or even avoiding some years to refill the gamma facility with additional cobalt.
- Having a back-up solution in case of an unexpected issue with one of the sterilization solutions.
Why IBA?
LEONI Studer Hard's collaboration with IBA is not new. They acquired and are still operating the first Rhodotron® E-beam accelerator from IBA. At that time, the Rhodotron® was new and brought to the market an innovative solution for E-beam sterilization. Over the past decades, the Rhodotron® proved to be a robust machine for the sterilization industry. Even though X-ray sterilization is a new technology, from a technical point of view it is based on IBA's well known Rhodotron®.
But having an X-ray generator is not enough. On top of the accelerator, an equally important topic is the product processing: how will products be presented to the X-ray field. The product conveying system configuration and planning was the result of LEONI Studer Hard AG's many years of experience as well as an in-depth and fruitful partnership with IBA. LEONI Studer brought the industrial experience of large processing facilities. IBA included in the partnership the system optimization experience based on simulations allowing to predict irradiation effects.
The Selected X-ray Configuration
The conclusion of the feasibility study was that the most appropriate solution allowing LEONI Studer Hard to best serve its customers was:
- IBA's eXelis® 1000: the X-ray generator based on the Rhodotron® TT1000 with an X-ray target.
- A 2-level pallet solution using a rolling conveying system designed by LEONI Studer Hard.
"The final configuration is an excellent compromise between optimal use of generated X-rays and efficient labor requirements for large facility processing".
Hans Joerg Hartmann, Managing Director of LEONI Studer Hard AG.
The main characteristics of the designed facility are:
- Quality
X-ray sterilization simulated Dose Uniformity Ratio (DUR) was much better than typical DUR of 1.45 for Gamma pallet processing. - Efficiency
By designing a 2-level conveying system, most of the X-rays are captured by the products. Losses of X-rays are minimized compared with a 1-level conveying system where the products must be over-scanned in order to achieve good Dose Uniformity. Overscanning means "losing" X-rays above and below the products. - Flexibility
Ability to mix different products with different dose requirements in the same irradiation cycle is possible since the solution is based on an incremental dose concept. One increment consists of four passes of the pallet in front of the X-ray target (pallet irradiated from the top and bottom, front and rear side). The increment dose is the minimum dose the product can receive. Any multiple of the increment dose can be given to the product by adding increments (ie: if increments have a value of 2.5 kGy, 25 kGy can be given to the product with 10 increments). - Capacity
Possibility to process very large volumes of medical devices on pallets with minimum labor required.
Start of Operations
DUR as low as 1.25 was measured for products with densities of 0.15 gr/cc sterilized on pallets. This is an improvement of 20% compared with gamma pallet irradiation
As part of the system qualification, material tests were performed in order to assess potential product activation. With the collaboration of an official Swiss lab, it was demonstrated that activation was under control and not an issue.
Today LEONI Studer Hard validated the X-ray sterilization technology for several products in commercial use in different fields of sterilization.
Operating Costs
eXelis®, the X-ray generator, is a 700kW peak accelerator powered by electricity. Operational costs depend mainly on the cost of electricity and the yearly production load. Some key advantages of using an electrically powered X-ray machine are:
Stop electricity consumption when needed
Contrarily to the cobalt natural (unstoppable) decay, you can stop the accelerator and thus its electrical consumption when production stops. With X-rays, electricity is consumed only when required.
Electricity at night rate
Plant managers can adapt production planning in order to fit with the most interesting electricity rate offered by the power provider. Many accelerator operators choose to favor night shifts for the main part of their production, due to reduced electricity costs.
Additional operational cost savings can be achieved by capturing the power dissipated by X-ray conversion and re-use this power to heat the building or offices.
About LEONI Studer Hard AG
LEONI Studer Hard provides E-beam, gamma and X-ray Irradiation services for partners all over Europe.
http://www.leoni-studerhard.com
About IBA
IBA is a leader in electron and proton accelerators for industrial applications. Its unique E-Beam, X-ray and Proton solutions are used across the world in medical device sterilization, food pasteurization, property enhancement, safety and detection, crystal modification.
More than 250 IBA Industrial accelerators are used in the world today, some for more than 50 years.
http://www.iba-sterilization.com
Contact: Philippe Dethier email: [email protected] Tel: +32-10-475892
SOURCE IBA Industrial
Share this article