Radiotracer determination of gold recovery in copper melting process

1989 ◽  
Vol 136 (3) ◽  
pp. 197-202 ◽  
Author(s):  
J. Thereska ◽  
T. Çuçi ◽  
E. Plasari ◽  
Z. Lleshi
2018 ◽  
Vol 60 ◽  
pp. 00027 ◽  
Author(s):  
Andrii Sudakov ◽  
Andrii Dreus ◽  
Diana Sudakova ◽  
Oleksandr Khamininch

The article presents the results of experimental and theoretical studies, the purpose of which was to substantiate the technology of drilling wells isolation using new thermoplastic composite material. The basis of the proposed material is gravel, and secondary polyethylene terephthalate acts as a binding material. The use of the proposed insulation material avoids a number of disadvantages specific for traditional grouting mortars. The technology of material application provides its melting in a well by thermomechanical drilling. The article deals with the issues, related to the substantiation of the optimal formulation of a thermoplastic composite material based on secondary polyethylene terephthalate, and the determination of rational operating parameters of thermomechanical drilling, which allow to melt effectively the material at the bottom of a well. The possibility of material application for the insulation of absorbing horizons in borehole conditions has been proved. Based on the analysis of the heat balance at the bottom of a well, the calculation procedure has been proposed and the dependences of the velocity and time of thermomechanical melting of the grouting thermoplastic composite material on the operating parameters of drilling, thermal properties and geometric characteristics of the drill bit, have been determined.


2015 ◽  
Vol 1744 ◽  
pp. 107-112
Author(s):  
Zachary J. Hilliard ◽  
Pavel R. Hrma

ABSTRACTTo efficiently vitrify Hanford waste, the melting process (i.e., melter feed turning into waste glass) must be modeled and optimized. The rate of heat transfer to the melter feed in a waste glass melter, and thus the rate of melting, is strongly affected by the melter feed porosity, especially in the final stages where the glass-forming melt produces foam that insulates the feed from the molten glass. The volume expansion test allows the determination of the melter feed porosity as a function of temperature. This test measures the profile area of the feed pellet as it turns into glass. This contribution presents the calculation of the void fraction (porosity) of the melter feed as a function of temperature, heating rate, and material parameters. The process of finding the void fraction is described as well as results from the application of this process.


Author(s):  
Tatyana D. Kalgashkina ◽  
◽  
Irina V. Provornaya ◽  

In this work, the method of integrated assessment is used to determine the economic assessment of accumulated environmental damage within the Komsomol gold recovery plant. Authors did the economic assessment of environmental damage to water and land resources caused by the plant's economic activities was calculated. The result of the work is the determination of the total assessment of environmental damage from the activities of the Komsomol gold recovery factory, which is 458,182 thousand rubles.


Author(s):  
Takashi S. Kodama ◽  
Yoshiyuki Tanaka ◽  
Miyo Morita ◽  
Takashi Yura ◽  
Yoshimasa Kyogoku ◽  
...  

1977 ◽  
Vol 32 (11) ◽  
pp. 1229-1238 ◽  
Author(s):  
A. Boos ◽  
S. Steeb

AbstractRecently1 a method was published for the determination of short range order parameters in binary melts and also a method for the determination of the concentration of different structures which form such a melt. These methods are used in the present work to evaluate the atomic structure of Mg-Cd-melts and to reveal the changes in short range order during the melting process.


1959 ◽  
Vol 32 (2) ◽  
pp. 463-470
Author(s):  
O. N. Trapeznikova ◽  
G. E. Smirnova

Abstract The process of formation and melting of neoprene crystallites was investigated by the polarized light scattering method. Conclusions about the nonreversibility of the crystallization and melting processes were drawn on the basis of angular distribution measurements of depolarized and polarized components of light scattered from polymer films. The appearance of a relatively small number of large crystallites is characteristic for the initiation of crystallization; further development of crystallization is accompanied by a decrease in the size of the crystallites. All crystallites disappear simultaneously during the melting process. The size of the crystallites determined by microphotography corresponds approximately to the particle size determined by the formula for isotropic, spherical particles. A method for the determination of the melting range of crystalline polymers is proposed.


Molecules ◽  
2021 ◽  
Vol 26 (7) ◽  
pp. 1840
Author(s):  
Urška Šunta ◽  
Polonca Trebše ◽  
Mojca Bavcon Kralj

Microplastics (MPs) have gained significant attention in the last two decades and have been widely researched in the marine environment. There are, however, less studies on their presence, routes of entry, and impacts on the biota in the soil environment. One of the main issues in the study of MPs is a lack of standardized methods for their identification in environmental samples. Currently the most commonly used techniques are thermal desorption gas chromatography–mass spectrometry (GC–MS) methods and pyrolysis followed by GC–MS. In this study, headspace-solid phase microextraction followed by GC–MS is proposed as a simple and widely applicable method for the determination of commonly present polymer MPs (polyethylene terephthalate, polystyrene, polyvinyl chloride, polyethylene, and polypropylene) in environmental samples, for analytical laboratories with basic equipment worldwide. The proposed method is based on the identification of compounds, which are formed during the well-controlled melting process of specific coarse (1–5 mm) and fine fraction (1 mm–100 μm) MPs. The method was upgraded for the identification of individual polymer type in blends and in complex environmental matrices (soil and algae biomass). The successful application of the method in complex matrices makes it especially suitable for widescale use.


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