Process engineering aspects and the further development of the onion irradiator GBZ 81

The gamma irradiator GBZ 81 is a specific onion irradiator and easy to use for all types of bulk-cargo irradiation. It largely works automatically. The irradiator may be integrated into the storing line of onions from the field to the warehouse. Its output is about 7.5–8.0 ton/h, corresponding to 2000–3000 ton per harvest period. The efficiency of the gamma irradiator is about 13%. Considering the low building cost, the simple design and the automatic operation of the irradiation plant this comparatively low efficiency is acceptable, especially if the cobalt-60 sources are used during the remaining times of the year in another facility, e.g. a multipurpose irradiator of a higher efficiency. This programme is realized at present by the combination of a new multipurpose gamma-irradiation facility and some onion irradiators of the type GBZ 81.