This study aims to beneficiate low grade goethitic iron ore fines using a selective flocculation process. Selective flocculation studies were conducted using different polymers such as starch amylopectin(AP), poly acr...This study aims to beneficiate low grade goethitic iron ore fines using a selective flocculation process. Selective flocculation studies were conducted using different polymers such as starch amylopectin(AP), poly acrylic acid(PAA), and a graft copolymer(AP-g-PAA). The obtained results were analyzed; they indicate the enhancement of the iron ore grade from 58.49% to 67.52% using AP-g-PAA with a recovery of 95.08%. In addition, 64.45% Fe with a recovery of 88.79% was obtained using AP. Similarly, using PAA, the grade increased to 63.46% Fe with a recovery of 82.10%. The findings are also supported by characterizing concentrates using X-ray diffraction(XRD) and electron probe microanalysis(EPMA) techniques.展开更多
Increased demand for iron ore necessitates the utilization of low-grade iron ore fines, slimes, and existing tailings. Selective flocculation can be an alternative physico-chemical process for utilizing these low-grad...Increased demand for iron ore necessitates the utilization of low-grade iron ore fines, slimes, and existing tailings. Selective flocculation can be an alternative physico-chemical process for utilizing these low-grade fines, slimes, and tailings. In selective fiocculation, the most critical objective is the selection of proper reagents that will make fioc of desired minerals. In present study, selective flocculation was applied to ultra-fine synthetic mixtures of hematite and kaolinite, and the Fe value was upgraded up to 65.78% with the reduction of Al2O3 and SiO2 values to 2.65% and 3.6670, respectively. Here, degraded wheat starch was used as a flocculant.In this process, separation occurs on the basis of the selectivity of the flocculant. The selectivity of the fiocculant can be quantified in terms of separation efficiency. Here, an attempt was also made to develop a correlation between separation efficiency and major operating parameters such as flocculent dose, pH value, and solid concentration to predict the separation performance.展开更多
An attempt has been made to investigate and optimize the recovery of Ni and Al through sulphuric acid(3.0-5.5 mol/L)leaching under different operating conditions.From the leaching experiments,it was possible to extrac...An attempt has been made to investigate and optimize the recovery of Ni and Al through sulphuric acid(3.0-5.5 mol/L)leaching under different operating conditions.From the leaching experiments,it was possible to extract 98.5%of NiO and 40.7%of Al_(2)O_(3)under the conditions of 5.5 mol/L H_(2)SO_(4),reaction time of 4 h,solid-to-liquid ratio 0.2 g/mL,temperature of 358 K,particle size<100μm,200-250 r/min with 5.0 g catalyst dosage.The leached liquor Al was separated by selective crystallization using 1.4 mol/L KOH and Ni was separated by selective precipitation using 0.3 mol/L H_(2)C_(2)O_(4).From the studies,it is possible to recover around 97.9%of NiO having 98.3%purity,around 25%of Al_(2)O_(3)was also recovered as alum-(K)having 99%purity and 14.7%of Al_(2)O_(3)as a salt of Al-K-C_(2)O_(4)-SO_(4).Sulphuric acid was found to be a suitable leaching agent for selective leaching and it was also observed that alum-(K)can be selectively crystallized from sulphate solutions.The study also indicated the effective extraction and recovery of nickel and aluminium which were well supported by characterization studies using TG-DTA/DTG and XRD techniques.展开更多
Because of the current depletion of high grade reserves, beneficiation of low grade ore, tailings produced and tailings stored in tailing ponds is needed to fulfill the market demand. Selective flocculation is one alt...Because of the current depletion of high grade reserves, beneficiation of low grade ore, tailings produced and tailings stored in tailing ponds is needed to fulfill the market demand. Selective flocculation is one alternative process that could be used for the beneficiation of ultra-fine material. This process has not been extensively used commercially because of its complex dependency on process parameters. In this paper, a selective flocculation process, using synthetic mixtures of hematite and kaolinite in different ratios, was attempted, and the ad-sorption mechanism was investigated by Fourier transform infrared （FTIR） spectroscopy. A three-layer artificial neural network （ANN） model （4？4？3） was used to predict the separation performance of the process in terms of grade, Fe recovery, and separation efficiency. The model values were in good agreement with experimental values.展开更多
基金the National Metallurgical Laboratory,Jamshedpur for their kind support
文摘This study aims to beneficiate low grade goethitic iron ore fines using a selective flocculation process. Selective flocculation studies were conducted using different polymers such as starch amylopectin(AP), poly acrylic acid(PAA), and a graft copolymer(AP-g-PAA). The obtained results were analyzed; they indicate the enhancement of the iron ore grade from 58.49% to 67.52% using AP-g-PAA with a recovery of 95.08%. In addition, 64.45% Fe with a recovery of 88.79% was obtained using AP. Similarly, using PAA, the grade increased to 63.46% Fe with a recovery of 82.10%. The findings are also supported by characterizing concentrates using X-ray diffraction(XRD) and electron probe microanalysis(EPMA) techniques.
基金funding given by CSIR,India,through project NWP-31 for carrying out this work
文摘Increased demand for iron ore necessitates the utilization of low-grade iron ore fines, slimes, and existing tailings. Selective flocculation can be an alternative physico-chemical process for utilizing these low-grade fines, slimes, and tailings. In selective fiocculation, the most critical objective is the selection of proper reagents that will make fioc of desired minerals. In present study, selective flocculation was applied to ultra-fine synthetic mixtures of hematite and kaolinite, and the Fe value was upgraded up to 65.78% with the reduction of Al2O3 and SiO2 values to 2.65% and 3.6670, respectively. Here, degraded wheat starch was used as a flocculant.In this process, separation occurs on the basis of the selectivity of the flocculant. The selectivity of the fiocculant can be quantified in terms of separation efficiency. Here, an attempt was also made to develop a correlation between separation efficiency and major operating parameters such as flocculent dose, pH value, and solid concentration to predict the separation performance.
文摘An attempt has been made to investigate and optimize the recovery of Ni and Al through sulphuric acid(3.0-5.5 mol/L)leaching under different operating conditions.From the leaching experiments,it was possible to extract 98.5%of NiO and 40.7%of Al_(2)O_(3)under the conditions of 5.5 mol/L H_(2)SO_(4),reaction time of 4 h,solid-to-liquid ratio 0.2 g/mL,temperature of 358 K,particle size<100μm,200-250 r/min with 5.0 g catalyst dosage.The leached liquor Al was separated by selective crystallization using 1.4 mol/L KOH and Ni was separated by selective precipitation using 0.3 mol/L H_(2)C_(2)O_(4).From the studies,it is possible to recover around 97.9%of NiO having 98.3%purity,around 25%of Al_(2)O_(3)was also recovered as alum-(K)having 99%purity and 14.7%of Al_(2)O_(3)as a salt of Al-K-C_(2)O_(4)-SO_(4).Sulphuric acid was found to be a suitable leaching agent for selective leaching and it was also observed that alum-(K)can be selectively crystallized from sulphate solutions.The study also indicated the effective extraction and recovery of nickel and aluminium which were well supported by characterization studies using TG-DTA/DTG and XRD techniques.
基金the funding given by Council of Scientific and Industrial Research(CSIR)India through project NWP-31 for this project
文摘Because of the current depletion of high grade reserves, beneficiation of low grade ore, tailings produced and tailings stored in tailing ponds is needed to fulfill the market demand. Selective flocculation is one alternative process that could be used for the beneficiation of ultra-fine material. This process has not been extensively used commercially because of its complex dependency on process parameters. In this paper, a selective flocculation process, using synthetic mixtures of hematite and kaolinite in different ratios, was attempted, and the ad-sorption mechanism was investigated by Fourier transform infrared （FTIR） spectroscopy. A three-layer artificial neural network （ANN） model （4？4？3） was used to predict the separation performance of the process in terms of grade, Fe recovery, and separation efficiency. The model values were in good agreement with experimental values.
