Das Trocknen von HTR-Brenn- und Brutstoffpartikeln und Erfahrungen mit einem Bandtrockner

摘要

In the fabrication of fissile and fertile material particles for high-temperature reactors, drying of the gel particles is a very important process step. First, the drying properties of ThO$_{2}$-(Th, U)O$_{2}$ and UO$_{2}$ gel particles were examined and a belt dryer for continuous drying was developed using the findings obtained. The parameters during examination of the drying properties were: Th/U ratio, content of organic accessory substances, residual concentration of ammonium nitrate, particle size, washing liquid, ageing and drying room atmosphere. The belt dryer developed, having a centre-to-centre distance of 2.5 m and a belt width of 350 mm, can be used for drying approx. 0.8 kg/h of heavy metal oxide particles. The particle residence time in the dryer is only 8 to 13 minutes.