Stone coal rotary kiln roasting process: The current process of extracting vanadium from stone coal is generally characterized by low and unstable vanadium conversion. Multi-factor rotary kiln roasting conditions were tested on different types of ore. The effect of the addition of additives on the conversion rate of vanadium roasting was investigated. The results show that the ore is calcined in a rotary kiln at 800 °C for 2 h, and then leached with a 4 g/L sulfuric acid solution at a liquid solid mass ratio of 3:1. The vanadium leaching rate is up to 85%, and continuous operation can be achieved. The centralized treatment of flue gas has changed the situation that the flat kiln roasting cannot be continuously operated and the flue gas disorderly discharge is difficult to handle, which is very favorable to the environment. Electric Offroad Scooter,Powerful Electric Motorcycle,Wide Wheel E Scooter,Lithium Battery Hybrid Scooter NINGBO FENGLI IMPORT & EXPORT TRADING CO., LTD , https://www.ewaspmobility.com