Abstract: During the commissioning of the Fangjiashan cement solidification line, the concentrate, spent resin solidification and spent filter fixation tests were conducted. The problems such as cement solidification formulations, equipment design, and equipment reliability were found in the tests. The cause for the problems is analyzed. The formula suit for out-drum mixing, mud fluidity, solidification performance and waste minimization should be developed. The equipment reliability problem should be solved from the aspects of equipment design, equipment selection and procurement. The engineering validation should be performed fully before application to the nuclear power plants to improve the reliability of the out-drum mixing process.