scholarly journals Iron Ore Slimes Flotation Tests Using Column and Amidoamine Collector without Depressant

Minerals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 699
Author(s):  
Lev Filippov ◽  
Klaydison Silva ◽  
Alexandre Piçarra ◽  
Neymayer Lima ◽  
Iranildes Santos ◽  
...  
Keyword(s):  
Iron Ore ◽  
Water Flow Rate ◽  
Pilot Scale ◽  
Industrial Plant ◽  
The Novel ◽  
Flotation Column ◽  
Iron Quadrangle ◽  
Rate Adjustment ◽  
In Series ◽  
Iron Ore Slimes

This work describes the concentration of iron ore slimes on a pilot scale by using a 500-mm diameter flotation column and a novel collector, which renders the use of a depressant unnecessary. The pilot column was operated in series with the industrial plant Vargem Grande 2 (Iron Quadrangle, Brazil) receiving, as feed, part of the underflow from the desliming thickener. These pilot tests represented only the rougher stage of a flotation circuit. The novel collector used was an amidoamine (average collector dosage of 160 g/t), and the tests were carried out in the absence of starch, at pH 10.5 and with bubbles/microbubbles generated by cavitation tube. It was possible to achieve a concentrate, by reverse flotation, with an average iron content of 53% and an average metallurgical recovery of 91.5% The recovery of the silica in the froth was 53.1% in average for one stage of flotation. The high variability of the slime characteristics rendered difficult the stabilization of the SiO2 recovery; however, the applicability of the amidoamine collector was proven. In an industrial scale circuit, the use of online analyzers for Fe and SiO2 content and the adoption of control logics based on the adjustment of parameters such as reagents dosage and washing water flow rate adjustment should contribute to the optimization of the results obtained in the pilot scale tests. Further studies adding a cleaner concentration stage should be performed.

scholarly journals Simulation of Thermal Effects on the Flow Field in a Pilot-Scale Kiln

2021 ◽  
Author(s):  
I. A. Sofia Larsson ◽  
Anna-Lena Ljung ◽  
B. Daniel Marjavaara
Keyword(s):  
Flow Field ◽  
Coal Combustion ◽  
Thermal Effects ◽  
Iron Ore ◽  
Combustion Process ◽  
Pilot Scale ◽  
Mixing Properties ◽  
Process Gas ◽  
Mixing Rates ◽  
Computational Fluid Dynamics Cfd

AbstractThe flow field and coal combustion process in a pilot-scale iron ore pelletizing kiln is simulated using a computational fluid dynamics (CFD) model. The objective of the work is to investigate how the thermal effects from the flame affect the flow field. As expected, the combustion process with the resulting temperature rise and volume expansion leads to an increase of the velocity in the kiln. Apart from that, the overall flow field looks similar regardless of whether combustion is present or not. The flow field though affects the combustion process by controlling the mixing rates of fuel and air, governing the flame propagation. This shows the importance of correctly predicting the flow field in this type of kiln, with a large amount of process gas circulating, in order to optimize the combustion process. The results also justify the use of down-scaled, geometrically similar, water models to investigate kiln aerodynamics in general and mixing properties in particular. Even if the heat release from the flame is neglected, valuable conclusions regarding the flow field can still be drawn.

Characterization and Processing of Iron Ore Slimes for Recovery of Iron Values

2014 ◽  
Vol 36 (3) ◽  
pp. 174-182 ◽  
Author(s):  
S. K. Jena ◽  
H. Sahoo ◽  
S. S. Rath ◽  
D. S. Rao ◽  
S. K. Das ◽  
...  
Keyword(s):  
Iron Ore ◽  
Iron Ore Slimes

scholarly journals Biological elimination of a high concentration of hydrogen sulfide from landfill biogas

2021 ◽  
Author(s):  
Rania Ibrahim ◽  
Abdessamad El Hassni ◽  
Shahram Navaee-Ardeh ◽  
Hubert Cabana
Keyword(s):  
Hydrogen Sulfide ◽  
Pilot Scale ◽  
Biotrickling Filter ◽  
High Concentration ◽  
Two Phase ◽  
Filter System ◽  
Biotrickling Filters ◽  
In Series ◽  
Maximum Elimination Capacity ◽  
Landfill Biogas

Abstract Hydrogen sulfide (H2S) is one of the main contaminants found in biogas which is one of the end products of the anaerobic biodegradation of proteins and other sulfur-containing compounds in solid waste. The presence of H2S is one of the factors limiting the valorization of biogas. To valorize biogas, H2S and other contaminants must be removed. This study evaluated the performance of a pilot-scale biotrickling filter system on H2S removal from landfill biogas. The biotrickling filter system, which was packed with stainless-steel pall rings and inoculated with an H2S-oxidizing consortium, was designed to process 1 to 10 SCFM of biogas and used to determine the removal efficiency of a high concentration of hydrogen sulfide from landfill biogas. The biofiltration system consisted of two biotrickling filters connected in series. Results indicate that the biofiltration system reduced H2S concentration by 94–97% without reduction of the methane concentration in the outlet biogas. The inlet concentration of hydrogen sulfide, supplied to the two-phase bioreactor, was in the range of 900 to 1500 ppmv. The hydraulic retention times (HRT) of the two biotrickling filters were 3.9 and 0.9 min, respectively. Approximately 50 ppmv of H2S gas was detected in the outlet gas. The maximum elimination capacity of the biotrickling filter system was found to be 272 g H2S.m− 3.h− 1. During the biological process, the performance of biotrickling filter was not affected when the pH of the recirculated liquid decreased to 2–3. The overall performance of the biotrickling filter system was described using a modified Michaelis–Menten equation, and the Ks and Vm values for the biosystem were 34.7 ppmv and 200 mg H2S/L.h− 1, respectively.

Corrigendum to: Pandora is on Earth: new species of Eukoenenia (Palpigradi) emerging at risk of extinction

2020 ◽  
Author(s):  
Maysa F. V. R. Souza ◽  
Rodrigo L. Ferreira
Keyword(s):  
New Species ◽  
Iron Ore ◽  
Mining Activities ◽  
Economic Interest ◽  
Brazilian Legislation ◽  
Iron Quadrangle ◽  
Minas Gerais State ◽  
Risk Of Extinction ◽  
Qualitative Characters

In 2008 the change to the Brazilian legislation regarding the use of natural caves has caused an increase in the number of studies on environmental impacts involving caves. The legislation requires the classification of such environments according to their importance, and caves that are not classified highly may be irreversibly impacted. Thus, caves in rocks of high economic interest have been intensively sampled, which has resulted in the collection of several specimens of Palpigradi in them. The Iron Quadrangle (in Minas Gerais state) stands out among these areas as one the most important sources of iron ore in Brazil. Several palpigrades from this region are housed in collections: most of them belong to the edaphic species Eukoenenia ferratilis, and a small portion belong to new species that are morphologically quite distinct from E. ferratilis, with longer bodies and more elongated appendages, indicating the presence of troglomorphisms. Therefore, the present study aimed to describe three new troglobitic species of Eukoenenia, which can be distinguished morphometrically and by means of some qualitative characters. These descriptions are important for the preservation of the caves where they occur, since the presence of troglobitic species increases the relevance of the caves, which have been severely threatened by mining activities.

Recovery of Iron Values from Discarded Iron Ore Slimes

2019 ◽  
Vol 37 (1) ◽  
pp. 287-295 ◽  
Author(s):  
Singh Rahulkumar Sunil ◽  
Veeranjaneyulu Rayapudi ◽  
Nikhil Dhawan
Keyword(s):  
Iron Ore ◽  
Iron Ore Slimes

scholarly journals The Characteristics of Iron Ore Slimes and Their Influence on The Flotation Process

Minerals ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 675
Author(s):  
Neymayer Pereira Lima ◽  
Klaydison Silva ◽  
Thiago Souza ◽  
Lev Filippov
Keyword(s):  
Particle Size ◽  
Iron Ore ◽  
Corn Starch ◽  
Reverse Flotation ◽  
Flotation Process ◽  
Froth Stability ◽  
Iron Ore Slime ◽  
Iron Ore Slimes ◽  
Main Effects

The flotation has been successfully applied to process the iron ore for the particle size (Ps) from 10 µm up to 150 µm. The presence of the slimes (Ps < 10 µm) is harmful on the reverse flotation of quartz, so they are usually prior removed by hydrocyclones. The main effects of the presence of slimes on the flotation are related to the increase on reagents consumption, the froth stability, and decrease on the selectivity. The lower floatability of coarse quartz particles (+74 µm) combined with the presence of slimes, even in small quantities, drastically affect the flotation response. This paper shows a study of characterization of a typical iron ore slime, aiming to create a better understanding of its role on the concentration by flotation. The main characteristics of typical slimes from the Iron Ore Quadrangle in Brazil are the presence of almost 70% of hematite, 25% of quartz, and 5% of kaolinite, as the main silicates gangue minerals. Furthermore, the particle size distribution revealed that 80% of the hematite and the kaolinite are below 20 µm. The affinity between the ultrafine kaolinite of the slimes with the corn starch is harmful to the reverse flotation of quartz, as the starch has an important depressing action over the hematite. The presence of 20% of hematite −20 µm decreased the recovery to the froth of quartz + 74 µm from 97% to 62%, where the slimes coating seems to be the main responsible.

Experimental and modeling evaluation of upward and downward velocities in the coaxial flotation column

2001 ◽  
Vol 43 (8) ◽  
pp. 195-201 ◽  
Author(s):  
K. Park ◽  
J.-M. Cho ◽  
J. Oh ◽  
K. Chung
Keyword(s):  
Removal Efficiency ◽  
Pilot Scale ◽  
Coaxial Cylinder ◽  
Treated Water ◽  
Flotation Column ◽  
Solids Loading ◽  
Solids Concentration ◽  
Upward Velocity ◽  
Solids Removal

This study was conducted to show the influence of upward velocity in the inner column and downward velocity in the outer column of the coaxial cylinder-type flotation column on the solids removal efficiency, solids concentration in the treated water, and so on. The SIMPLE (Semi-Implicit Method for Pressure Linked Equation) solution was applied to the coaxial flotation column to simulate the velocity vectors of the elements of water flowing in the column. The effects of solids loading and residence time in the agglomerate separation zone on the solids removal efficiency were also tested. In the pilot scale coaxial DAF column experiments with solids concentration of 1,000–2,000 mg of SS per liter and solids loading less than 350 kg/m2/day, approximately 90% of the solids removal efficiencies were obtained using the upward velocity of up to 110 cm/min in the contact zone of the inner column and the downward velocity of up to 30 cm/min in the outer column. In the simulation, similar results were observed as in the experiments. The solids loading in the excess of 350 kg/m2/day caused the instability of the sludge float layer and aggravated the quality of the treated water.

Pig Wastewater Treatment in Water Hyacinth Ponds

1992 ◽  
Vol 26 (9-11) ◽  
pp. 2381-2384 ◽  
Author(s):  
C. Polprasert ◽  
S. Kessomboon ◽  
W. Kanjanaprapin
Keyword(s):  
Wastewater Treatment ◽  
Water Hyacinth ◽  
Loading Rate ◽  
Pilot Scale ◽  
Operating Conditions ◽  
Cod Removal ◽  
Organic Loading Rate ◽  
Small Scale ◽  
N Removal ◽  
In Series

Small-scale and pilot-scale experiments were conducted on pig wastewater treatment in water hyacinth (Eichhornia crassipesl ponds. The main objectives were to evaluate the treatment performance of the water hyacinth ponds and to determine suitable operating conditions. From the experimental results obtained, the optimum organic loading rate was found to be 200 kg COD/(ha.d), while the hydraulic retention times were proposed to be 10-20 days. The % COD removal in the small-scale water hyacinth ponds were 74-93, while for the pilot-scale ponds the % COD removal were 52-72 because of fluctuations in the influent wastewater characteristics and occasional insect attacks on the water hyacinth leaves and stems. Similar results were obtained for N removal. Although the water hyacinth ponds were found to be feasible for pig wastewater treatment, at least one polishing pond in series should be provided to polish the water hyacinth pond effluents before discharging into the environment.

Pilot Investigation on Mechanical Stirred and Pneumatic Drying of Bagasse with Boiler Flue Gases

2012 ◽  
Vol 512-515 ◽  
pp. 1193-1198
Author(s):  
Shao Ji Zhou ◽  
Quan Yu ◽  
Xiao Yu Qin ◽  
Si Yuan Zhang
Keyword(s):  
Pilot Scale ◽  
Flue Gases ◽  
The Novel ◽  
Power Demand ◽  
Optimal Operating ◽  
Pressure Drops ◽  
Factors Affecting ◽  
Pneumatic Drying ◽  
Pilot Investigation ◽  
Drying Efficiency

A novel system of mechanical stirred and pneumatic drying of bagasse with boiler flue gases was developed and experimented on pilot scale in a sugar mill. Investigation was performed on factors affecting the dried bagasse moisture content, the drying efficiency of the dryer, and the pressure drops of both the dryer and the separating cyclone. Optimal operating conditons were found to be stirring speed 40 rpm, throughput of the pilot dryer 1000 kgh-1, and flow rate of flue gases 4500 kgh-1. The pressure drops of the dryer and the cyclone were less than 100 Pa and 250 Pa respectively. The novel system was superior to conventional dryers on both the drying efficiency and the power demand by the induced fan.

Sign in / Sign up

Export Citation Format

Share Document