Research on the characteristic of power consumption in a novel rotating drum bioleaching reactor of different sizes

Abstract

A novel rotating drum bioreactor (RDB) with the volume of 18L and 96L in our previous work has shown the potential for bioleaching processes with high solid concentration. In this paper, a larger RDB with a volume of 703L was scaled up, and effect of operation condition and baffle parameters on power consumption in the 96L and 703L RDBs was investigated. The results showed that the specific power consumption increased with the rotation speed and was insensitive to aeration rate. Meanwhile, the specific power consumption was negatively related to loading coefficient and was positively related to diameter of RDB. It was found that the power consumption increased with the increase of number and width of baffles. The mass transfer performance was most economic, when the 703L RDB was equipped with 8 baffles with a 0° angle. The mass transfer performance of the 703L RDB at the same specific power was close to that of a stirred tank bioreactor (STB) commercially used. For the Al2O3 slurry system, the specific power consumption in the 703L RDB was less than 1/3 of that in the traditional STB with the same diameter.