J. Samaniego; M.A.N. Tanchuling
Abstract
The use of amalgamation process to recover gold from mined ores by the small-scale gold miners in the Philippines and other developing countries produces and dispose of untreated wastewater to the receiving water bodies. In this study, a field-scale filter bed system was constructed to treat heavy metal ...
Read More
The use of amalgamation process to recover gold from mined ores by the small-scale gold miners in the Philippines and other developing countries produces and dispose of untreated wastewater to the receiving water bodies. In this study, a field-scale filter bed system was constructed to treat heavy metal metal-laden wastewater collected from small-scale gold mining site in Paracale, Camarines Norte, Philippines. The filter bed system was consists of sedimentation tank and filter bed with Cocopeat, a by-product of coconut husk, as adsorbent. Physico-chemical parameters (temperature, pH, oxidation-reduction potential, electrical conductivity, turbidity, dissolved oxygen, total dissolved solids, salinity, total suspended solids, color) and heavy metal (As, Ba, Cd, Hg, Pb) concentrations were monitored during the 50 days experiment at a flow rate of 40 Liter per hour for 3 hours daily wastewater application. Significant reduction was achieved on heavy metals; As (97.11%), Ba (39.75%), Cd (74.24%), Hg (97.02%), Pb (98.82%) from small-scale gold mining (SSGM)wastewater in sedimentation phase and further reductions on As (1.39%), Ba (28.00%), Cd (4.95%), Hg (2.91%), Pb (0.97%) were achieved by adsorption in the Cocopeat filter bed. Measured effluent physico-chemical parameters and heavy metal concentrations were within the respective regulatory limits. Other effluent parameters with strong correlation with total suspended solids such as turbidity and color, though not regulated, were reduced significantly. All adsorbed heavy metals accumulated in the upper 25 cm of the Cocopeat column in the filter bed. Measured heavy metal concentrations in Cocopeat suggest that the adsorbent was not saturated and further application of small-scale gold mining wastewater is recommended to determine its useful life.
A.R. Karbassi; M. Pazoki
Abstract
In this study, the concentrations of heavy metals (Ca, Zn, Cu, Fe, Mn, Ni) in thesediment of Shavoor River in Khuzestan Province in Iran has been investigated. After the library studies and field studies, six samples of water and sediment were taken from the river in order to evaluate heavy metal pollution ...
Read More
In this study, the concentrations of heavy metals (Ca, Zn, Cu, Fe, Mn, Ni) in thesediment of Shavoor River in Khuzestan Province in Iran has been investigated. After the library studies and field studies, six samples of water and sediment were taken from the river in order to evaluate heavy metal pollution in sediments. To determine the geochemical phases of metals in sediment samples the 5-step method was used for chemical separation. For quantitative assessment of the severity of contamination in the sediments, the geochemical indicators such as enriched factor (EF) and the accumulation index (Igeo) were used. Also, the statistical analyses including methods such as correlation analysis cluster analysis the (CA), were conducted.The results of the experiments showed that the organic matter deposited varies with the average of 2.49 and ranges between 1.95% and 3.43%. Samples showed concentrations of metals such as calcium, iron, manganese, copper and nickel at all the sampling points were below the global average, whereas the concentration of copper was slightly higher than the global scale. Enriched factor (EF) was calculated for the elements revealed that heavy metals are classified as non-infected. The Geo-accumulation Index showed that the studied elements were uninfected peers. Based on the results of multivariate statistical analysis it was concluded that metals such as manganese, copper, iron, nickel and zinc are mainly natural and calcium metal is likely to have an organic origin.