云南潞西大矿山铅锌矿

矿体产于花岗岩以上断层附近大理岩中,大理岩与花岗岩接触部位是主要的矿化部位,在大矿山、小石林、灰窑等地见有强褐铁矿化、弱铅锌矿化的厚大矿化层。通过勘查工作,认为矿区具有寻找中-大型规模矿山的前景。

Cadmium in agricultural soils,vegetables and rice and potential health risk in vicinity of Dabaoshan Mine in Shaoguan,China

Soil cadmium(Cd)contamination resulted from mining and smelting is a major environmental concern,and health risk associated with Cd exposure to multi-media through muti-pathway is increasing.Cd concentrations in soils,vegetables and paddy rice were investigated,and potential non-carcinogenic and carcinogenic health risks exposure to Cd were estimated at six villages around the Dabaoshan Mine,South China.A total of 87 soil samples were found to exceed the China's maximum permission level(MPL)for Cd,while the highest value of 4.42 mg/kg was found near irrigation ditch associated with Hengshi River in Xinyi(XY)Village.Cd contents in vegetables and rice exceeded the maximum permissible concentration by more than five times in every village.Cadmium accumulation in plants is in the order of celery>lactuca sativa L>Chinese cabbage>Romaine lettuce>asparagus lettuce>mustard>cabbage mustard>cabbage.The mean hazard quotient(HQ)of all villages is in the range of [5.29,25.75],and the mean values of cancer risk for investigated areas are more than 10 times greater than the USEPA(2009)threshold limit value of 10-4.Moreover,human non-carcinogenic and carcinogenic risks are mainly attributable to paddy rice intake,followed by vegetables intake,soil ingestion,inhalation,and dermal contact.The results indicate that Cd has a huge potential risk on human health for the local residents.

Acid mine drainage and heavy metal contamination in groundwater of metal sulfide mine at arid territory (BS mine,Western Australia)

The issues of acid mine drainage （AMD） and heavy metals contamination in the metal sulfide mine in the add district were explored, through studying the acidification and the heavy metals distribution and evolution of groundwater in the black swan （BS） nickel sulfide mine （Western Australia）. The groundwater samples were collected from the drilling holes situated in the vicinity of tailings storage facility （TSF） and in the background of the mine （away from TSF）, respectively, and the pH and electric conductivity （Ec） were measured in site and the metal contents were analysed by ICP-MS and ICP-AES, quarterly in one hydrological year. The results disclose that the TSF groundwater is remarkably acidified （.pHmean=5, pHmin=3）, and the average contents of heavy metals （Co, Cu, Zn, Cd） and Al, Mn are of 1-2 orders of magnitude higher in TSF groundwater than in background groundwater. It may be due to the percolation of tailings waste water from miU process, which leads the tailings to oxidize and the deep groundwater to acidify and contaminate with heavy metals. Besides, the heavy metals concentration in groundwater may be controlled by pH mainly.

Research on the control technology of medium-length hole blasting fragmentation in underground mine

The scalloped medium-length hole blasting mining method used in Dahongshan Copper Mine accounted for more than 61%of the total amount of mining,but the large boulder yield restricted the intensity of ore supply for mines,and the average boulder yield was as high as 22.7%.In order to develop the mine production efficiency,the circular medium-length hole blasting technology was proposed and field tests were carried out.The test results showed that circular medium-length hole blasting mining can reduce the average boulder yield to 10.3%.Compared with the traditional scalloped medium-length hole blasting mining,the average boulder yield was decreased by 12.4%.The daily yield of ore for the panel on duty was increased by 152.29 t,and the growth rate was 51.1%.The new technology can reduce the time for the handling of boulder and the consumption of explosives and detonators for recrushing,and increase the efficiency of mining while reduce the mining cost,which has received good blasting effects.

Measurement and numerical analysis of influence of key stratum breakage on mine pressure in top-coal caving face with super great mining height

To analyze the influence of movement in shallow-buried working faces with large mining heights on mine pressure manifestation, the key stratum at a working face was categorised using the 1313 top-coal caving face with super great mining height under cover as a case study. The research combined theoretical analysis, field measurement, and numerical simulation to analyze the influencing mechanism of key stratum. Moreover, the research results were verified by numerical simulation and indicate that the sub-key stratum is prone to be broken to form a "cantilever beam" structure rather than a stable hinged structure during the excavation of working faces with super great mining heights. When the "cantilever beam" structure is unstable, a low pressure will occur on the working face, and the overlying strata will subside simultaneously with the sub-key stratum to induce the breakage of the primary key stratum: the breakage will further trigger the periodic breakage of sub-key stratum, causing a greater load on the working face. Finally, steps, and strength of weighting in the working face vary to be great or small alternatively. This is the main reason explaining why the 1313 working face shows strong mine pressure manifestation. The results provide theoretical and practical experience for forecasting and controlling mine pressure manifestation.

Heavy Metal Contamination in Soil and Soybean near the Dabaoshan Mine, South China

Concentrations of Pb, Cd, Cu, Zn, Cr and Ni in soybean (Glycine max L.) grown near the Dabaoshan Mine were investigated, and their potential risk to the health of inhabitants was estimated. In the Fandong (FD) and Zhongxin (ZX) villages, which are near the Dabaoshan mineral deposit, concentrations of Pb (0.34 mg kg^(-1) for FD), Cd (0.23 mg kg^(-1) for ZX) and Cr (1.14 and 1.75 mg kg^(-1) for FD and ZX, respectively) in the seeds of soybean exceeded the tolerance limit set by Chinese standards. The estimated daily intakes (EDIs) from consumption of soybean seeds for FD inhabitants were 0.570, 0.170, 38.550, 142.400, 1.910 and 14.530 μg d^(-1) kg^(-1) boby weight for Pb, Cd, Cu, Zn, Cr and Ni, respectively. Our results indicate that soybeans grown in the vicinity of the Dabaoshan Mine accumulate some metals, and the seeds pose a potential health risk to the local inhabitants.