Papers by Hamid Reza Manouchehri
Mining, Metallurgy & Exploration, 2014
Pyrrhotite (Po) is one of the most abundant sulfide minerals in processing industry and must be r... more Pyrrhotite (Po) is one of the most abundant sulfide minerals in processing industry and must be rejected in most cases. Particularly, Po rejection and its selectivity against pentlandite (Pn) have long been a challenge due to similarities in the mineral composition of the two minerals and the collectorless flotation characteristics of Po. Xanthates have been widely used to promote sulfide mineral flotation; however, in the presence of xanthates, the redox potential established at the mineral/solution interface is most important, determining the flotation performance. In this paper, the importance of electrochemistry in Po and Pn flotation has been demonstrated and a comprehensive study was conducted on two different feed streams (i.e., magnetic concentrate and scavenger cleaner streams, containing magnetic and nonmagnetic forms of Po, respectively), from Vale’s Clarabelle Mill in Sudbury, Ontario, with an objective to determine if improvements in Po rejection and Pn recovery could b...
Particulate Science and Technology, 2001
The tribo/contact electrification theory of materials is envisaged from the chemical Lewis acid-b... more The tribo/contact electrification theory of materials is envisaged from the chemical Lewis acid-base concept and an attempt has been made to find a correlation between these two phenomena. The donor-acceptor/acid-base properties of apatite, calcite, feldspar, quartz and wollastonite mineral samples have been determined by electrokinetic studies in water and in different organic solvents having different donicity values. From the results,
Magnetic and Electrical Separation, 2002
The triboelectric charge attributes of the pure feldspar, quartz and wollastonite mineral samples... more The triboelectric charge attributes of the pure feldspar, quartz and wollastonite mineral samples, after contact with plate and cyclone type tribochargers made up of different materials were investigated. The main electrical properties of the minerals, i.e., electrical conductivity and dielectric constant, were measured and their energetic work functions were estimated. In addition, the behaviour of mineral samples in the electric field of a free-fall separator before and after chemical treatment with different organic reagents was deduced. The results reveal that the cyclone tribochargers are more effective in imparting charges on mineral grains. The reproducible charges with higher magnitudes are created when cyclones are used for imparting charges on mineral grains. Furthermore, in spite of having relatively similar energetic structures for the three minerals, the Teflon tribocharger demonstrates the feasibility of quartz separation from wollastonite and feldspar. The salicylic acid conditioning promotes feldspar-wollastonite separation.
and defined temperature and relative humidity was found to be essential to concentrate wollastoni... more and defined temperature and relative humidity was found to be essential to concentrate wollastonite. The outcomes indicate despite the fact that triboelectric charge and separation process has not been completely perceived, it pronounced to be an environmentally friendly and economically viable technique for minerals and wastes beneficiation. Being a dry beneficiation technique the process has special appeal, which must be explored further in particular for treating industrial minerals.
by dry magnetic separation. Investigation indicated the separation would be inefficient without c... more by dry magnetic separation. Investigation indicated the separation would be inefficient without comminuting the feed. The results showed promising, taking into account that there is no need for water (dry process) and thereby no need for water treatment and water recycling. Furthermore, the energy consumption is minimal.
high enough to allow the formation of dixanthogen on its surface promoting its flotation. This ca... more high enough to allow the formation of dixanthogen on its surface promoting its flotation. This can be controlled by monitoring the potential values for the mineral electrodes. Experimental results showed selective separation can be achieved when low to moderate oxidation (o to 100 mV) and reduction (-20 to -100 mV) potentials are monitored by pentlandite and pyrrhotite electrodes respectively. Furthermore, monitoring of the pentlandite, Pn, and Pyrrhotite, Po, electrodes indicated that a good separation of pentlandite from pyrrhotite is achieved when Pn electrode indicates slight oxidation during flotation, whereas, Po electrode shows slightly reduction.
Mining, Metallurgy & Exploration, 2000
The fundamentals of electrical separation, the electrical properties of minerals, the principal m... more The fundamentals of electrical separation, the electrical properties of minerals, the principal methods usedfor charging minerals and their mechanisms, the effective factors controlling the acquisition of charges by minerals, the general configuration of commercial electric separators and the forces operating during electrical separation of minerals are reviewed and presented.
Proceedings of XXV International Workshop on Deep-Inelastic Scattering and Related Subjects — PoS(DIS2017), 2017
This document presents the recent results of the ATLAS experiment at the LHC concerning the tt re... more This document presents the recent results of the ATLAS experiment at the LHC concerning the tt resonance and vector-like quark searches. A search for tt resonances at 13 TeV in protonproton collisions data is performed in the lepton+jet final state and for boosted top topologies. A re-interpretation of the analysis performed with the data recorded at the center of mass energy of 8 TeV, is also presented, for a scalar resonant signal. A vector-like top pair production is also searched for, through three analyses where the vector-like quark decay to Zt, Ht or Wb. A comparison of those analyses is presented. In addition, vector-like quarks are searched via the same sign lepton topology. The results are presented as mass limits on the vector-like top branching ratio plane and as the cross section limit on the T 5/3 pair production.
In spite of having long past, due to process, economic and operational limits, sorting has not me... more In spite of having long past, due to process, economic and operational limits, sorting has not met big success in mineral processing. However, advances in sensing and quantifying raw material surface characteristics in connection with rapid growth in computing and software technology as well as considerable enhancements in optical resolution and related electronic component made it possible to rely on sorting process more and more. Furthermore, growing technological awareness and skills of the machine users as well as increasing the technical support by sorter manufacturers are other optimistic factors in growing the acceptance of sorting machine. However, lack of consistent, easy to be maintained, and low cost ejector system are big losses. Thus what should be aimed in future is to develop new machines based on reliable sensing and ejection systems to promote sorting application. Sorting process, its advances and limitations are discussed within this paper. Some new sorting machine...
Attempts were made to examine the possibilities for utilizing optoelectronic sorting tests on peg... more Attempts were made to examine the possibilities for utilizing optoelectronic sorting tests on pegmatite containing about 40% of the mica shists. High quality pegmatite products were achieved, where ...
The triboelectric charge attributes of feldspar, quartz and wollastonite minerals, after contacti... more The triboelectric charge attributes of feldspar, quartz and wollastonite minerals, after contacting different triboecharging medium made of different materials, were considered. Their charge acquis ...
Large variations in flotation characteristics of minerals have been observed in winter and summer... more Large variations in flotation characteristics of minerals have been observed in winter and summer in plant practices as a result of changes in pulp temperature. Variations in temperature may affect ...
It is known that the grinding condition has a major effect on the beneficiation characteristics o... more It is known that the grinding condition has a major effect on the beneficiation characteristics of the minerals in subsequent processing, in particular, flotation. In the flotation process, particles surface and their condition can significantly influence collector adsorption and flotation performance. For example, particle shape and its surface roughness occurred during grinding may influence flotation characteristics of a specific ore. In fact, adsorption of different cationic and anionic species on mineral surfaces can be varied depending on the selected comminution procedure. The flotation performance of sulphide minerals can be detrimentally affected by the surface oxidation. The amount of surface oxidation may reduce the hydrophobicity of the mineral and makes adsorption of collectors less selective. Improved liberation may generally result in improved flotation recovery. However, this may result in finer grinding and slimes, and consequently, reduce the overall flotation reco...
Characterizing triboelectric separation behaviour ofcalcite and quartz before and after chemical ... more Characterizing triboelectric separation behaviour ofcalcite and quartz before and after chemical treatment
Correlation between the electrical properties of quartz, feldspar and wollastonite minerals and t... more Correlation between the electrical properties of quartz, feldspar and wollastonite minerals and their tribo-electric separation potential
Despite the fact that triboelectric separation process has not been completely perceived, it pron... more Despite the fact that triboelectric separation process has not been completely perceived, it pronounced to be environmentally amiable and economically viable for minerals and wastes beneficiation, ...
Uploads
Papers by Hamid Reza Manouchehri