Abstract: Drying process is an available technology used for volume reduction treatment of radwaste, and has been applied to deal with spent resin generated from NPP in foreign. However, the study and application of the technology is still at the initial stage in China. On the basis of a series of process tests which included transporting, metering, drying, cleaning up of off-gas etc, the drying process with electric-heating, pressure controlling and agitating for spent resin treatment was achieved and a 1:1 scale prototype drying equipment was established. Verification and optimization tests of the spent resin drying treatment were carried out. The results demonstrate that the drying equipment is reliable and safe for the treatment of spent resin from NPP. Under the conditions of 280 ℃, (-70±3) kPa and 30 rpm agitation rate, 350 L resin (IRN160, nuclear class) was treated within nearly 20 h. The maximum evaporation rate, average evaporation rate and reduction coefficient is 9.92 kg/h, 6.31 kg/h and 2.4 respectively. The humidity of dried resin is less than 15%.

Key words: spent resins, volume reduction, drying, conical dryer