After the pre-oxidation of intensified alkaline leaching under normal temperature and pressure,the dissolution of gold by NaCN was enhanced to 85.85%,and the adsorption recovery by activated charcoal was 99.62%.
The repair of inner lining of blast furnace by gunning is a new valuable technique developed in recently years The main problems encountered in the recovery process of blast furnace after gunning, such as once rapid recovery, slag of remained gunning materials, slag and hot metal output etc are discussed based on the experience of more than 30 times of gunning repairing It is suggested that the key is to control temperature in BF properly and to gain a good term work
Due to sufficient preparation work advanced, the blast furnace operation was safe, smooth and high efficient during blow in. All tuyeres work after blow in for 47 hours, so the full blast operation is achieved, which hits the shortest record of BF blow in recovery in Angang.
When the temperature 765 ℃, reductant mass 10%, residual press 80 Pa, and time 2 h, antimony of more than 72% is volatilized into the condensate, lead of more than 71% is reduced into the Pb-Sb alloy, and most of tin is remained in the volatilizing residues with the direct recovery rate of antimony and lead reaching 92.95% and 71.20%, respectively.