Pilot-scale counter-current acid leaching process for Cu, Pb, Sb, and Zn from small-arms shooting range soil

In order to study heavy metals’ pollution characteristics in soil of a small arms shooting range, soil samples at surfaces and different depths were collected from a shooting range located in suburb of Beijing and analyzed for heavy metals (Pb、Cd、Cu、Zn、P、As、Hg and Sb). Site investigation results showed that the soil in the shooting range was seriously polluted by Pb bullets, and there are positive correlations between total concentrations of Hg, Cu, Pb, Zn, Sb and Pb in soil particles less than 2mm, indicating soil heavy metals’ combined pollution characteristics.

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Direct Acid Leaching of Vanadium from Stone Coal

High Temperature Materials and Processes ◽

10.1515/htmp-2016-0055 ◽

2017 ◽

Vol 36 (9) ◽

pp. 877-883 ◽

Cited By ~ 1

Author(s):

Bo Zhang ◽

Zhaoguo Gao ◽

Hongzhao Liu ◽

Wei Wang ◽

Yaohua Cao

Keyword(s):

Sulfuric Acid ◽

Acid Leaching ◽

Influential Factors ◽

Process Conditions ◽

Stone Coal ◽

Leaching Process ◽

Maximum Value ◽

Orthogonal Experiments ◽

Counter Current ◽

Leaching Efficiency

AbstractThis paper focused on optimizing the process conditions of direct acid leaching process to enhance the leaching efficiency of leaching vanadium from the stone coal. Orthogonal experiments and single factor experiments were conducted to investigate the effect of the influential factors of direct acid leaching on vanadium leaching ratio. The results showed that the vanadium leaching ratio reached the maximum value of 89.22 % under the optimal process conditions of CaF2 dosage 5 mass%, H2SO4 dosage 40 mass%, leaching temperature 95 °C and leaching time 10 h. Furthermore, the reaction mechanisms of the main influencing factors were analyzed. Finally, the two-stage counter-current leaching process was adopted to decrease the consumption of sulfuric acid and neutralizer, and the results indicated that the consumption of sulfuric acid decreased 12.50 % as well as neutralizer decreased 35.80 %.

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376. Ability of Minor Increases in Indoor Shooting Range air Velocities to Reduce Lead Concentrations in the Breathing Zone of Small-Arms Shooters

10.3320/1.2758412 ◽

2004 ◽

Author(s):

D. Lillquist ◽

B. Craig

Keyword(s):

Breathing Zone ◽

Shooting Range ◽

Small Arms

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Study on Ultrasonically-Enhanced Sulfuric Acid Leaching of Nickel from Nickel-Containing Residue

Crystals ◽

10.3390/cryst11070810 ◽

2021 ◽

Vol 11 (7) ◽

pp. 810

Author(s):

Zhanyong Guo ◽

Ping Guo ◽

Guang Su ◽

Fachuang Li

Keyword(s):

Sulfuric Acid ◽

Acid Leaching ◽

Ultrasonic Waves ◽

Sulfuric Acid Leaching ◽

Solid Product ◽

Leaching Process ◽

Diffusion Controlled ◽

Extraction Degree ◽

Ultrasonic Conditions ◽

Complex Nickel

In this paper, nickel-containing residue, a typical solid waste produced in the battery production process, was used to study the cavitation characteristics of ultrasonic waves in a liquid–solid reaction. The ultrasonically-enhanced leaching technology for multicomponent and complex nickel-containing residue was studied through systematic ultrasonic-conventional comparative experiments. An ultrasonic leaching kinetics model was established which provided reliable technological guidance and basic theory for the comprehensive utilization of nickel-containing residue. In the study, it was found that ultrasonically-enhanced leaching for 40 min obtained the same result as conventional leaching for 80 min, and the Ni extraction degree reached more than 95%. According to the kinetic fitting of the leaching process, it was found that the sulfuric acid leaching process belonged to the diffusion-controlled model of solid product layers under conventional and ultrasonic conditions, and the activation energy of the reaction was Ea1 = 17.74 kJ/mol and Ea2 = 5.04 kJ/mol, respectively.

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Carbonate and citric acid leaching of uranium from uranium-contaminated soils: Pilot-scale studies (Phase II)

10.2172/130633 ◽

1995 ◽

Cited By ~ 3

Author(s):

J.H. Wilson ◽

R. Chernikoff ◽

W.D. DeMarco

Keyword(s):

Citric Acid ◽

Phase Ii ◽

Contaminated Soils ◽

Acid Leaching ◽

Pilot Scale

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