Raman, Gireesh S. S.Klima, Mark S.Bishop, Jenna M.
9页
查看更多>>摘要：Pressure filtration offers the opportunity to produce solids (filter cake) that can be stacked or mixed with the coarse refuse, and water (filtrate) that can be recirculated in the plant. In this study, the bench-scale pressure filtration testing was performed to dewater coal refuse slurry, which was obtained from the thickener underflow stream of a coal preparation plant, and was being discharged into a slurry impoundment. A flexible fractional factorial design was developed to determine the effects of pressure, pH, and solids concentration on the performance of filtration, which was measured in terms of filtrate flux. The results indicated that the pH had a maximum effect on the filtrate flux followed by the pressure and solids concentration. Additionally, a linear regression model and an Artificial Neural Network (ANN) model were developed to predict the filtrate flux based on the test variables. Both models were able to fit the data well, with R-2 values of 0.986 and 0.991 for the linear regression model and the ANN model respectively. It was also found that the test dataset had a mean squared error of 0.2 for the ANN model, while it was 3.99 for the regression model. (C) 2016 Elsevier B.V. All rights reserved.
查看更多>>摘要：The adsorption of copper ions and the formation of a copper sulfide phase on pyrite surfaces are of vital importance to alter the surface property of pyrite and determine its fate either to be rejected in the flotation of polymetallic sulfide ores or to be recovered in the flotation of pyritic gold ores. Cyanide and copper may coexist in the process water with complicated speciation. The objective of this study is to Understand the interaction between copper cyanide species and pyrite and clarify the possible adsorption of copper on pyrite surfaces from cyanide-bearing solutions. Surface-enhanced Raman spectroscopy and electrochemical measurements were used to determine the reaction products formed on pyrite surfaces. It was found that Cu(I)-bearing species were incorporated into pyrite, forming a CuS-like sulfide from copper cyanide solutions at a more oxidizing potential, while a Cu2S-like sulfide formed at a more reducing potential. The amount of copper deposited on pyrite was significantly improved at a more reducing potential at which the pyrite surface tended to be FeS-like. In addition, these Cu(I)-sulfides on pyrite surfaces were dissolved by cyanide-bearing species at a high CN/Cu ratio, compromising the total amount of copper uptake. (C) 2016 Elsevier By. All rights reserved.
NSTL
Elsevier