Influence of Air Flow Rate and Immersion Depth of Designed Flotation Cell on Barite Beneficiation

2016 ◽  
Vol 867 ◽  
pp. 66-70
Author(s):  
Nantawat Demeekul ◽  
Lek Sikong ◽  
Manoon Masniyom
Keyword(s):  
Flow Rate ◽  
Air Flow ◽  
Immersion Depth ◽  
Alkaline Condition ◽  
Enrichment Ratio ◽  
Chemical Compositions ◽  
Air Bubbles ◽  
Air Flow Rate ◽  
Flotation Cell ◽  
Concentrate Grade

This study aims to investigate the effect of flotation operating parameters such as immersion depth of downcomer and air flow rate on performance of barite minerals separation. The barite minerals utilized in this experiment mainly consist of barite and gangue minerals such as quartz, kaolinite, illite and microcline having the chemical compositions of 63.12% BaSO4, 18.22% SiO2, 13.49%Al2O3, 1.02% K2O, 0.69% Fe2O3 and 3.46% others and the particle size (d80) of about 37 microns. In the flotation cell, the air bubbles were generated using designed porous materials. The flotation of barite minerals were carried out in an alkaline condition at pH 9 with sodium oleate collector and terpineol frother. It was found that concentrate grades of barite for the air flow rates of 20, 30 and 40 L/min were nearly constant about 70% BaSO4 at the immersion depths of 5 and 10 cm but it increased at the depth of 15 cm. The immersion depth of 5 and 10 cm seems to have no effect on grade of concentrate while the depth of 15 to have such effect. The air flow rate had an effect on concentrate grade when 15 cm immersion depth was used. The optimum air flow rate of 30 L/min gave concentrate grade of 85% BaSO4 with the recovery and enrichment ratio of 73% and 1.3, respectively.

Air Entrainment and Bubble Generation by a Hydrofoil in a Turbulent Channel Flow

2019 ◽  
Author(s):  
Ichiro Kumagai ◽  
Kakeru Taguchi ◽  
Chiharu Kawakita ◽  
Tatsuya Hamada ◽  
Yuichi Murai
Keyword(s):  
Channel Flow ◽  
Flow Rate ◽  
High Speed ◽  
Air Flow ◽  
Air Entrainment ◽  
Air Bubbles ◽  
Air Flow Rate ◽  
Bubble Generation ◽  
Gas Liquid Flow ◽  
Entrained Air

Abstract Air entrainment and bubble generation by a hydrofoil bubble generator for ship drag reduction have been investigated using a small high-speed channel tunnel with the gap of 20 mm in National Maritime Research Institute (NMRI). A hydrofoil (NACA4412, chord length = 40 mm) was installed in the channel and an air induction pipe was placed above the hydrofoil. The flow rate of the entrained air was quantitatively measured by thermal air flow sensors at the inlet of the air induction pipe. The gas-liquid flow around the hydrofoil was visualized by a backlight method and recorded by a high-speed video camera. As the flow velocity in the channel increased, the negative pressure generated above the suction side of the hydrofoil lowered the hydrostatic pressure in the channel, then the atmospheric air was entrained into the channel flow. The entrained air was broken into small air bubbles by the turbulent flow in the channel. The threshold of air entrainment, the air flow rate, and gas-liquid flow pattern depends on Reynolds number, angle of attack (AOA), and hydrofoil type. We identified at least three modes of air entrainment behavior: intermittent air entrainment, stable air entrainment, and air entrainment with a ventilated cavity. At high flow speed in our experimental condition (9 m/s), a large volume of air bubbles was generated by this hydrofoil system (e.g. air flow rate was 50 l/min for NACA4412 at AOA 16 degrees), which has a high potential to reduce ship drag.

Air Sparging for Mixing Non-Newtonian Slurries

2010 ◽  
Author(s):  
Judith Ann Bamberger ◽  
Carl W. Enderlin ◽  
S. Tzemos
Keyword(s):  
Flow Regime ◽  
Flow Rate ◽  
Air Flow ◽  
Newtonian Fluids ◽  
Air Sparging ◽  
Air Bubbles ◽  
Air Flow Rate ◽  
Primary Flow ◽  
Zone Of Influence ◽  
Made In

The mechanics of air sparger systems have been primarily investigated for aqueous-based Newtonian fluids. Tilton et al. (1982) [1] describes the fluid mechanics of air sparging systems in non-Newtonian fluids as having two primary flow regions. A center region surrounding the sparger, referred to as the region of bubbles (ROB), contains upward flow due to the buoyant driving force of the rising bubbles. In an annular region, outside the ROB, referred to as the zone of influence (ZOI), the fluid flow is reversed and is opposed to the direction of bubble rise. Outside the ZOI the fluid is unaffected by the air sparger system. The flow regime in the ROB is often turbulent, and the flow regime in the ZOI is laminar; the flow regime outside the ZOI is quiescent. Tests conducted with shear thinning non-Newtonian fluid in a 34-in. diameter tank showed that the ROB forms an approximately inverted cone that is the envelop of the bubble trajectories. The depth to which the air bubbles reach below the sparger nozzle is a linear function of the air-flow rate. The recirculation time through the ZOI was found to vary proportionally with the inverse square of the sparging air-flow rate. Visual observations of the ROB were made in both water and Carbopol®. The bubbles released from the sparge tube in Carbopol® were larger than those in water.

Optimization of oxygen transfer in clean water by fine bubble diffused air system and separate mixing in aeration ditches

1998 ◽  
Vol 38 (3) ◽  
pp. 35-42 ◽  
Author(s):  
G. Déronzier ◽  
Ph. Duchène ◽  
A. Héduit
Keyword(s):  
Water Flow ◽  
Flow Rate ◽  
Oxygen Transfer ◽  
Contact Time ◽  
Air Flow ◽  
Interfacial Area ◽  
Design Parameters ◽  
Air Bubbles ◽  
Air Flow Rate ◽  
Fine Bubble

The influence of design parameters on the transfer of oxygen was studied in different ring ditches equipped with fine bubble membrane air diffusers and separate mixing. The results produced evidence that the oxygen transfer efficiency (OTE) decreases when the air flow rate per diffuser increases. OTE increases asymptotically with the horizontal water flow (50% for velocity up to 0.5 m/sec). It increases also when the diffuser modules are brought closer together. Theoretical analysis enabled ranking of the impact of the design parameters on which the oxygen transfer is dependent, namely the interfacial area (a) and the oxygen transfer coefficient (Kl). The increase in the air flow rate per diffuser essentially reduces the interfacial area by an increase in the diameter of the initial air bubbles and by a reduction of the contact time due to an acceleration of the “spiral flows” (vertical rotation of water flow). The horizontal rotation of water increases the interfacial area most probably by decreasing the diameter of the initial air bubbles and by a lengthening of the contact time resulting from a reduction in the large spiral flows. Bringing the diffuser modules closer together makes longer the contact time by a reduction in the large spiral flows.

Air Bubble Size Measurement in a Laboratory Flotation Cell

2014 ◽  
Vol 530-531 ◽  
pp. 160-165
Author(s):  
Xiao Feng Xie ◽  
Rong Gang Li
Keyword(s):  
Porous Media ◽  
Image Analysis ◽  
Flow Rate ◽  
Bubble Size ◽  
Air Flow ◽  
Bubble Surface ◽  
Gas Holdup ◽  
Air Flow Rate ◽  
Air Bubble ◽  
Flotation Cell

Air bubble size distribution in a laboratory flotation cell was investigated by using of image analysis technology in this paper. Results showed that it was feasible to determine the air bubble size according to image analysis software. For a porous media-aerated flotation cell, bubble size was dependent on poles size of porous media. Furthermore, operating parameters of the cell could affect the size. Mean bubble diameters increased with increasing of air flow rate. In contrast, it decreased when adding deinking agent. Its decreasing with increasing pulp flow rate under given conditions illustrated the fact that proper turbulence strength at the inlet of air bubbles was favorable for reducing bubble size. Gas holdup increased with increasing air flow rate to some extent, but it had a peak value. Gas holdup would rise obviously when deinking agent existed. An efficient approach to enhancing bubble surface area flux was to increase air flow rate and keep small bubble size at the same time.

Study on Potato Protien Recovery by Batch Foam Separation

2013 ◽  
Vol 807-809 ◽  
pp. 1236-1240
Author(s):  
Yi Zhang ◽  
Hai Wei Ren
Keyword(s):  
Flow Rate ◽  
Protein Concentration ◽  
Air Flow ◽  
Enrichment Ratio ◽  
Separation Performance ◽  
Air Flow Rate ◽  
Liquid Loading ◽  
Potato Protein ◽  
Foam Separation ◽  
Recovery Percentage

The feasibility of foam separation as a technique was assessed for the recovery of potato protein from the simulated potato processing waste effluent (SPWE). The effects of initial protein concentration, pH, air flow rate ,liquid loading volume on separation performance were examined by using a foam fractionation column with partial horizontally flowing foam phase. Based on the comprehensive consideration of effect on the enrichment ratio and the recovery percentage, the optimal conditions were initial protein concentration 0.5 g/L, initial pH 4.0, air flow rate 62.5 L/h ,liquid loading volume 200mL, Under the conditions, a greater enrichment ratio of the protein of 9.1 was obtained with a recovery percentage of the protein of 84.3%.The research are aimed at laying a foundation for the industrialization of recovering potato protein from the wastewater by foam separation.

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