scholarly journals Influence of raw material composition of Mediterranean pinewood on pellet quality

2017 ◽  
Vol 99 ◽  
pp. 90-96 ◽  
Author(s):  
Victoria Lerma-Arce ◽  
Jose-Vicente Oliver-Villanueva ◽  
Guillermo Segura-Orenga
2016 ◽  
Vol 30 (2) ◽  
pp. 237-243 ◽  
Author(s):  
Karolina Szulc ◽  
Andrzej Lenart

Abstract The paper presents an influence of raw material composition and technological process applied on selected physical properties of food powders. Powdered multi-component nutrients were subjected to the process of mixing, agglomeration, coating, and drying. Wetting liquids ie water and a 15% water lactose solution, were used in agglomeration and coating. The analyzed food powders were characterized by differentiated physical properties, including especially: particle size, bulk density, wettability, and dispersibility. The raw material composition of the studied nutrients exerted a statistically significant influence on their physical properties. Agglomeration as well as coating of food powders caused a significant increase in particle size, decreased bulk density, increased apparent density and porosity, and deterioration in flowability in comparison with non-agglomerated nutrients.


2021 ◽  
Vol 27 (6) ◽  
pp. 31-39
Author(s):  
N. Medyanik ◽  
◽  
E. Leontieva ◽  
O. Mishurina ◽  
E. Mullina ◽  
...  

The article analyzes the possibility and efficiency of processing stale tailings of flotation plants of the copper pyrite complex. The resource potential, material composition and technological capabilities of processing a number of technogenic objects are considered. The interrelation and influence of mineralogical and technological factors on the choice of tailings processing technology are analyzed. The results of chemical, mineral and phase analysis of stale flotation tailings of the studied pyrite ores are presented. According to the complex studies’ results, it is established that the stale flotation tailings of copper pyrite ores belong to a refractory type of geo-resources due to the high content of pyrite and low, at the level of ppm, gold and silver content, which are present mainly in the “resistant” minerals - chalcogenides, sulphides, their intergrowths. The article presents a factor analysis and conditions for the elemental composition of tailings formation: mineralogical, technological and environmental. The territorial accessibility and technological capability of the investigated technogenic formations are analyzed. In the course of experimental studies, the elemental composition of stale tailings has been revealed - the main components of which are: iron, sulfur, silicon and aluminum. According to the results of X-ray phase analysis, it has been found that the main ore mineral of the tailings is pyrite. At the same time, it is noted that the main share of gold in the stale flotation tailings is presented in the form of sulphides in the form of finely dispersed and isomorphic inclusions. The heterogeneous morphometric and mineral composition of sulphide aggregates, their difficult opening and high dispersion characterize stale tailings as a raw material that is difficult to float. The revealed features of the material composition of stale tails indicate the impossibility of extracting valuable components (gold and silver) from this resource using existing traditional technologies. It has been proved that it is possible to effectively extract precious metals from this category of raw materials only after their deep opening by chemical processing. The relevance of the research lies in the need to process gold-containing man-made waste in order to significantly expand the raw material base of mining enterprises, as well as to improve the ecological situation of the city-forming mining enterprises of the South Urals. The aim of the research is to study the material composition of stale tailings and develop a technology for selective extraction of gold and silver. The object of research is the stale flotation tailings of copper-pyrite enterprises of the Southern Urals. The subject is the mineral composition, the content of useful components of lying tailings and the technology of gold and silver selective extraction from them. Material and research methods. During the experiments, a set of physicochemical and chemical methods of analysis has been used: thermodynamic analysis, synchronous thermal analysis using a combined thermal analyzer of the Netzsch STA 449 F3 Jupiter brand, UV spectroscopy with an automated data processing system), qualitative chemical and assay analyzes


2011 ◽  
Vol 31 (9-10) ◽  
pp. 1973-1983 ◽  
Author(s):  
A. López ◽  
I. de Marco ◽  
B.M. Caballero ◽  
M.F. Laresgoiti ◽  
A. Adrados ◽  
...  

2020 ◽  
pp. 27-34
Author(s):  
D. G. Chistyakov ◽  
◽  
V. O. Golubev ◽  
V. M. Sizyakov ◽  
V. N. Brichkin ◽  
...  

It is well known that an unstable composition of ore and auxiliary materials creates the need to manage material flows and their composition in order to ensure the required productivity and achieve the desired qualitative and quantitative characteristics of the final products. The above problem was decided to find a solution for through analysis and mathematical processing of the RUSAL Achinsk database containing data on the incoming nepheline ore and limestone. Thus, one could analyze variations in the ore composition and carry out a statistical analysis by calculating the root-mean-square (standard) deviation and the variation coefficient. A digital model of the alumina and soda product production process employed by RUSAL Achinsk was used as the main tool for calculating production indicators as a function of the raw material composition. The model was built by RUSAL ETC on the basis of lumped parameters modelling. It is shown that the chemical composition of the raw materials supplied to RUSAL Achinsk and their variability in the current operating conditions of the Kiya-Shaltyr nepheline mine and Mazoul limestone mine have a significant impact on the alumina and by-product production process and some adjustment of the process flows is required. It was estimated how the output and the consumption of soda-sulfate mixture and potash are likely to change depending on the concentration of Al2O3, K2O, Na2O and SO3 in the feed material. Based on the obtained results, one can identify the most innovative process solutions that would enable to raise the output of by-products while maintaining the output of alumina due to the introduction of appropriate corrective ingredients. In this case, the output of potassium sulfate is expected to rise from 1.22 to 5.78%, and that of soda ash — from 1.27 to 6.5%, which determines a significant increase in profit for these two products. This research study was funded by the Russian Science Foundation under the Grant Agreement No. 18-19-00577 dated 26th April 2018 on fundamental scien tific research and exploratory scientific research.


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