Abstract:Gravity settlement regularity of solid particles and liquid lead beads in hot molten salt was studied and settlement and separation conditions of solid and molten salt were optimized. The results show that sequence of settling velocity about such solid particles, i.e., ZnS, ZnO and liquid lead beads, is Pb>ZnS>ZnO, and settling velocity rises with increase of temperature. Settling temperature should not be higher than 900 ℃ because trend for reaction between ZnS and Na2CO3 to produce ZnO will rise which is bad for sulfur-fixation of ZnO. More than 80 percent of ZnS and ZnO particles settle to bottom of reactor to realize hot separation from molten salt under the conditions including salt solid ratio of 2.8, temperature of 900 ℃, and heat preservation time of 3 h. More than 92 percent of liquid lead can be settled to bottom of reactor within a short time and less than 2 percent of lead remains on surface of molten salt.