Effects of Sodium Peroxide Additives on Dielectric Properties and Microwave Roasting Mechanism of Zinc Sulfide Concentrate

Microwave technology has a potential application in the extraction of zinc from sulphide ores, knowledge of the dielectric properties of these ores plays a major role in the microwave design and simulation for any process. The dielectric properties of zinc sulfide concentrate for two different apparent densities—1.54 and 1.63 g/cm3—have been measured by using the resonance cavity perturbation technique at 915 and 2450 MHz during the roasting process for the temperature ranging from room temperature to 850 °C. The variations of dielectric constant, the dielectric loss factor, the dielectric loss tangent and the penetration depth with the temperature, frequency and apparent density have been investigated numerically. The results indicate that the dielectric constant increases as the temperature increases and temperature has a pivotal effect on the dielectric constant, while the dielectric loss factor has a complicated change and all of the temperature, frequency and apparent density have a significant impact to dielectric loss factor. Zinc sulfide concentrate is high loss material from 450 to 800 °C on the basis of theoretical analyses of dielectric loss tangent and penetration depth, its ability of absorbing microwave energy would be enhanced by increasing the apparent density as well. The experimental results also have proved that zinc sulfide concentrate is easy to be heated by microwave energy from 450 to 800 °C. In addition, the experimental date of dielectric constant and loss factor can be fitted perfectly by Boltzmann model and Gauss model, respectively.

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Dielectric Properties of Zinc Sulfide Concentrate during the Roasting at Microwave Frequencies

Minerals ◽

10.3390/min7020031 ◽

2017 ◽

Vol 7 (2) ◽

pp. 31 ◽

Cited By ~ 5

Author(s):

Guangjun He ◽

Shiwei Li ◽

Kun Yang ◽

Jian Liu ◽

Peng Liu ◽

...

Keyword(s):

Dielectric Properties ◽

Zinc Sulfide ◽

Microwave Frequencies ◽

Sulfide Concentrate

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Dielectric Properties of Zinc Sulfide Concentrate during the Roasting at Microwave Frequencies

10.20944/preprints201702.0044.v2 ◽

2017 ◽

Author(s):

Guangjun He ◽

Shiwei Li ◽

Kun Yang ◽

Jian Liu ◽

Peng Liu ◽

...

Keyword(s):

Dielectric Constant ◽

Dielectric Properties ◽

Dielectric Loss ◽

Zinc Sulfide ◽

Apparent Density ◽

Loss Tangent ◽

Loss Factor ◽

Microwave Energy ◽

Dielectric Loss Factor ◽

Sulfide Concentrate

Microwave technology has a potential application in the extraction of zinc from sulphide ores, knowledge of the dielectric properties of these ores plays a major role in the microwave design and simulation for any process. The dielectric properties of zinc sulfide concentrate for two different apparent densities—1.54 and 1.63 g/cm3—have been measured by using the resonance cavity perturbation technique at 915 and 2450 MHz during the roasting process for the temperature ranging from room temperature to 850 °C. The variations of dielectric constant, the dielectric loss factor, the dielectric loss tangent and the penetration depth with the temperature, frequency and apparent density have been investigated numerically. The results indicate that the dielectric constant increases as the temperature increases and temperature has a pivotal effect on the dielectric constant, while the dielectric loss factor has a complicated change and all of the temperature, frequency and apparent density have a significant impact to dielectric loss factor. Zinc sulfide concentrate is high loss material from 450 to 800 °C on the basis of theoretical analyses of dielectric loss tangent and penetration depth, its ability of absorbing microwave energy would be enhanced by increasing the apparent density as well. The experimental results also have proved that zinc sulfide concentrate is easy to be heated by microwave energy from 450 to 800 °C. In addition, the experimental date of dielectric constant and loss factor can be fitted perfectly by Boltzmann model and Gauss model, respectively.

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Distinct Roles of Acidophiles in Complete Oxidation of High-Sulfur Ferric Leach Product of Zinc Sulfide Concentrate

Microorganisms ◽

10.3390/microorganisms8030386 ◽

2020 ◽

Vol 8 (3) ◽

pp. 386 ◽

Cited By ~ 3

Author(s):

Maxim Muravyov ◽

Anna Panyushkina

Keyword(s):

Microbial Community ◽

Zinc Sulfide ◽

Elemental Sulfur ◽

Waste Product ◽

Sulfur Oxidation ◽

Low Grade ◽

Sulfide Concentrates ◽

Sulfide Concentrate ◽

Elemental Sulfur Oxidation ◽

Ferric Leaching

A two-step process, which involved ferric leaching with biologically generated solution and subsequent biooxidation with the microbial community, has been previously proposed for the processing of low-grade zinc sulfide concentrates. In this study, we carried out the process of complete biological oxidation of the product of ferric leaching of the zinc concentrate, which contained 9% of sphalerite, 5% of chalcopyrite, and 29.7% of elemental sulfur. After 21 days of biooxidation at 40 °C, sphalerite and chalcopyrite oxidation reached 99 and 69%, respectively, while the level of elemental sulfur oxidation was 97%. The biooxidation residue could be considered a waste product that is inert under aerobic conditions. The results of this study showed that zinc sulfide concentrate processing using a two-step treatment is efficient and promising. The microbial community, which developed during biooxidation, was dominated by Acidithiobacillus caldus, Leptospirillum ferriphilum, Ferroplasma acidiphilum, Sulfobacillus thermotolerans, S. thermosulfidooxidans, and Cuniculiplasma sp. At the same time, F. acidiphilum and A. caldus played crucial roles in the oxidation of sulfide minerals and elemental sulfur, respectively. The addition of L. ferriphilum to A. caldus during biooxidation of the ferric leach product proved to inhibit elemental sulfur oxidation.

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Study of ZnO Neutralization & Iron-Precipitation Test in Zn Concentrate Pressurization and Lixiviation

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.968.138 ◽

2014 ◽

Vol 968 ◽

pp. 138-141

Author(s):

Ting Xi Zhou ◽

Jin Hui Peng ◽

Zhi En Kuang ◽

Ji Kun Wang

Keyword(s):

Zinc Sulfide ◽

Iron Removal ◽

Optimal Parameters ◽

Time Duration ◽

Iron Precipitation ◽

Sulfide Concentrate ◽

Precipitation Test

The effect of ZnO dosage, iron remover and the time duration of neutralization and iron-precipitation on iron removal percentage was investigated to find out the optimal parameters in the technique of ZnO pressurization, neutralization and iron removal, and the residual acid from pressurization lixiviation and neutralization was assayed by using ZnO ore to neutralize and remove iron from lixiviated mineral pulp containing residual acid 20 g/l by simulation of Zn concentrate pressurization and lixiviation in a 2 L autoclave, in order to simplify Zinc pressurization process. The result showed that when Zn lixiviation percentage is higher than 98 %, up to 99.74 % of iron in the lixiviation fluid could be precipitated and the lixiviated fluid contains iron at the level of 20 mg/l, meeting the requirement on pre-purification fluid. Keywords: Zinc Sulfide Concentrate; Pressurization and Lixiviation; ZnO Ore; Neutralization and Iron Precipitation

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Oxidative Roasting of Low Grade Zinc Sulfide Concentrate from Gagok Mine in Korea

MATERIALS TRANSACTIONS ◽

10.2320/matertrans.m2010045 ◽

2010 ◽

Vol 51 (8) ◽

pp. 1481-1485 ◽

Cited By ~ 6

Author(s):

Byung-Su Kim ◽

Soo-Bock Jeong ◽

Young-hun Kim ◽

Hyung-Seok Kim

Keyword(s):

Zinc Sulfide ◽

Low Grade ◽

Oxidative Roasting ◽

Sulfide Concentrate

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Frequency dependent optical and dielectric properties of zinc sulfide in Terahertz regime

Infrared Physics & Technology ◽

10.1016/j.infrared.2014.03.013 ◽

2014 ◽

Vol 65 ◽

pp. 67-71 ◽

Cited By ~ 3

Author(s):

Satya R. Ganti ◽

S.K. Sundaram ◽

John S. McCloy

Keyword(s):

Dielectric Properties ◽

Zinc Sulfide ◽

Frequency Dependent

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Enriching Indium Using Neutralization from Solution Bearing Indium

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.287-290.2952 ◽

2011 ◽

Vol 287-290 ◽

pp. 2952-2956

Author(s):

Yong Gang Li ◽

Da Jin Yang ◽

Jian Rong Peng ◽

Xiao Ying Li

Keyword(s):

Sulfuric Acid ◽

Optimal Condition ◽

Zinc Sulfide ◽

Recovery Rate ◽

Acid Leaching ◽

Sulfide Mineral ◽

Optimal Dosage ◽

Sulfuric Acid Leaching ◽

Leaching Solution ◽

Sulfide Concentrate

An experimentation project has been put forward to enrich indium from sulfuric acid leaching solution bearing high content of indium: preneutralization using calcine---reduction using zinc sulfide concentrate---neutralization using limestone for precipitating indium, and ascertained optimal dosage of reagent in every procedure through experiment under certain condition: the dosage of calcine is 1.3 times of theoretic value, the dosage of zinc sulfide mineral concentrate is 2.2～2.3 times of theoretic value, the dosage of limestone is double of theoretic value. On this optimal condition, the straight recovery rate of indium is more than 97%, and the content of indium sediment from precipitating is more than 0.1%.

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