Effect of physical and chemical properties of vanadium slag from stone coal on the form of vanadium

Vanadium mining and smelting activities were increasing extensively and causing serious vanadium pollution in soil around the mining area. Different existing forms of vanadium had different biological effects and the exchangeable state had been recognized as a severe threat to biodiversity and ecosystem functioning. At present, the research on vanadium morphology had not received much attention. In this study, the area that we researched had been severely polluted with vanadium due to mining and smelting activities. The changes in the morphology of vanadium in soil were studied by adjusting the organic matter content, clay mineral content, pH value, and Eh value. The results showed that at pH 8 and for 1% of humic acid added, the exchangeable fraction of vanadium in the slag was 10% and 9%, respectively, which was 5% and 6% lower than the control group. The addition of kaolin and the redox change had little effect on the exchangeable fraction of vanadium, with a change of only about 2%. To control the soil pollution caused by slag and to repair its ecological characteristics, kaolin and humic acid were used for the repair test. The results showed that after 1% humic acid mixed with 8% kaolin was added in soil, the germination rate of ryegrass reached 95% and grew flourishingly which is significantly better than other treatment groups. Our research can provide a reference for future vanadium pollution control, especially in the morphology of vanadium research.