asghar azadehranjbar

Mining and minerals extraction and purification are critical in today’s world. However, these processes may have negative consequences on the environment. Xanthates which are essential in the floatation process are found to be significant polluting chemicals. In this manuscript, the effect of different parameters on the recovery of lead from Nakhlak lead mine was investigated considering the impact of used chemicals on the surrounding environment including air, soil and native plant species. The reason for this investigation was to achieve the optimal conditions for the minimum consumption of xanthates and other chemicals. The optimal recovery was obtained in the presence of xanthate (1 kg/t) and sodium silicate (0.4 kg/t). In addition, MIBC showed to be more efficient in the floatation process. Furthermore, it was observed that higher xanthate contents are required for the floatation of large particles. Therefore, smaller particles of feed can decrease xanthate consumption. A particle size of 100 µm showed the best floatation recovery with the least xanthate requirement.

Mining and related activities has a several impact on the environment. Heavy elements enter the environment through mining, ore processing and tailings dams.plants adsorb heavy metals through the soil, and heavy metals entered the foodchain. Nakhlak lead mine is 2000 years old and is located in the east of Nain city. In this study, the amount of heavy metals in the soil around Nakhlak lead mine has been investigated. Accumulation of heavy metals in native plants of the region as well as their bioavailability has been determined. For this purpose, 10 stations were selected for sampling the soil of the mineral zone and 10 stations for the soil of the tailings dam and by using atomic absorption, the amount of heavy metals in them was investigated. Plants were sampled from the most polluted areas. Bioavailability was simulated using EDTA solution. Among the plants of Claire, oleander and sagebrush, the highest accumulation was seen in Claire. Cadmium was more bioavailable than all heavy metals.