scholarly journals Analysis of a grinding efficiency in the electromagnetic mill for variable process and feed parameters

2017 ◽  
Vol 18 ◽  
pp. 01012
Author(s):  
Marta Wołosiewicz-Głąb ◽  
Dariusz Foszcz ◽  
Daniel Saramak ◽  
Tomasz Gawenda ◽  
Damian Krawczykowski

Article describes issues related to the assessment of raw materials grinding efficiency in an electromagnetic mill. Application of such type of mill in grinding processes can result in measurable benefits of more efficient raw material grinding by reducing time needed to produce a product of a suitable particle size compared to conventional mills. The expected effect of application of a system based on an electromagnetic mill is to achieve a lower energy consumption of grinding process for raw material processing compared to the existing equipment used for the fine grinding. A key element of correct design of comminution circuits in processing of particular feed mineral is to identify the impact of key factors affecting the efficiency of the grinding process. The most important factors determining the efficiency of the grinding process are the time, the construction parameters of the machine, the type of grinding media used in grinding process, as well as the parameters of the feed, among others the crushing resistance or particle size. The paper presents the results of kinetic study of copper ore grinding in electromagnetic mill for variable feed particle size distribution of and different sizes of grinding media.

2018 ◽  
Vol 8 (8) ◽  
pp. 1322 ◽  
Author(s):  
Marta Wołosiewicz-Głąb ◽  
Paulina Pięta ◽  
Dariusz Foszcz ◽  
Szymon Ogonowski ◽  
Tomasz Niedoba

The paper presents a study on the effectiveness of the grinding process in an electromagnetic mill devoted to ultrafine grinding, and the influence of processing parameters on the mill’s performance. The research was focused on the optimization of the duration of the grinding process and selection of the grinding media type in order to obtain the highest relative increase of the selected particle size fraction. Copper ore with a particle size between 0–1 mm was used in the experiments. A model was created that determines the relationship between the processing time and efficiency of the grinding, and can be used for the optimization of the process. A comparison of the relative growth of particle size fractions in milling products was performed. The obtained milling efficiency results measured by the growth of the analyzed particle size fraction in the milling product confirmed that the best grinding media set includes a grinding medium with a diameter of 1 mm and a length of 10 mm.


Materials ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2008
Author(s):  
Dariusz Urbaniak ◽  
Henryk Otwinowski ◽  
Tomasz Wyleciał ◽  
Vladimir Pavlovich Zhukov ◽  
Aleksei Yevgenyevich Barochkin ◽  
...  

Raw materials are used in many industrial technologies. The raw material frequently has to be prepared as an intermediate with an appropriate particle size distribution, which requires the use of grinding. In grinding processes, energy consumption is a very important profitability criterion for the applied particular size reduction technology. The paper describes the comminution process that takes place in the jet mill using a modified form of the thermodynamic theory of grinding. In this theory, new material characteristics have been added: the surface and volumetric density of grinding energy. The thermodynamic theory is a combination of the classical Kick’s theory and the modified form of Rittinger’s theory. The tested physical magnitudes are a measure of the energy consumption of the grinding process. They describe the energy that must be provided in the grinding process to overcome interactions between particles related to the volume and surface of the material. Knowledge of these magnitudes is necessary to model thermomechanical phenomena in the solid state. The paper presents the results of research on comminution in a jet mill, on the basis of which the values of the tested material magnitudes were determined. It is graphically shown how the values of the tested magnitudes depend on the grain size of the ground samples.


2020 ◽  
Vol 12 (24) ◽  
pp. 10454
Author(s):  
Katarína Teplická ◽  
Martin Straka

This article summarizes the arguments within the scientific discussion on the issue of using mining machines and their life cycle. The main goal of the article is to investigate the impact of a combination of mobile and stationary mining machines and their optimal distribution in the mining process to increase the efficiency of mining and processing of raw materials. The following methods of research were focused on the use of technical indicators for the valuation efficiency of the mining process: a simulation method was used for the distribution of mining machines, comparison analysis was used for the real and past state of mining machines, and a decision tree was used as managerial instrument for optimal alternatives of mining machines. The research empirically confirms and theoretically proves that optimal distribution of mining machines and machine parks is very important for mining companies. The benefit of this research for the mining company was the new location of the machines and the combination of stationary production lines and mobile equipment. The optimal layout of the machines reduced the number of conveyor belts and improved the transfer of limestone processing to mobile devices, saving time, which was reflected in transport costs. The results can be useful for other mining companies seeking to create an optimal machine park.


Author(s):  
David Miles ◽  
Adrian Heald ◽  
Mike Stedman

Vaccination against the COVID-19 virus began in December 2020 in the UK and is now running at 5% population/week. High Levels of social restrictions were implemented for the third time in January 2021 to control the second wave and resulting increases in hospitalisations and deaths. Easing those restrictions must balance multiple challenging priorities, weighing the risk of more deaths and hospitalisations against damage done to mental health, incomes and standards of living, education outcomes and provision of non-Covid-19 healthcare. Weekly and monthly officially published values in 2020/21 were used to estimate the impact of seasonality and social restrictions on the spread of COVID-19 by age group, on the economy and healthcare services. These factors were combined with the estimated impact of vaccinations and immunity from past infections into a model that retrospectively reflected the actual numbers of reported deaths closely both in 2020 and early 2021. It was applied prospectively to the next 6 months to evaluate the impact of different speeds of easing social restrictions. The results show vaccinations are significantly reducing the number of hospitalisations and deaths. The central estimate is that relative to a rapid easing, the avoided loss of 57,000 life years from a strategy of relatively slow easing over the next 4 months comes at a cost in terms of GDP reduction of around £0.4 million/life-year loss avoided. This is over 10 times higher than the usual limit the NHS uses for spending against Quality Adjusted Life Years (QALYs) saved. Alternative assumptions for key factors affecting give significantly different trade-offs between costs and benefits of different speeds of easing. Disruption of non-Covid-19 Healthcare provision also increases in times of higher levels of social restrictions. In most cases, the results favour a somewhat faster easing of restrictions in England than current policy implies.


2021 ◽  
Vol 129 ◽  
pp. 07005
Author(s):  
Nikola Slastanova ◽  
Marek Hlodak ◽  
Hubert Palus

Research background: The global environment influences the behaviour of companies. This concerns the requirements for increasing number of products, product lines, brands, the need for market segmentation, consumer demand, innovations as well as the behaviour of consumers and suppliers including environmentally appropriate purchasing. The forest-based industries must respond to changes from the perspective of the globalization process by appropriate adaptation and, inter alia, to focus on the introduction of environmentally properly procurement. The integration of green purchasing principles into business systems is increasingly mentioned in the process of globalization of economies in connection with the huge potential for gaining a sustainable competitive advantage. Purpose of the article: The aim of the paper is to identify and analyze the factors affecting the implementation of environmentally friendly purchasing in the companies of forest-based sector in Slovakia. Methods: The reasons for implementing responsible practices in supply chains are based either on the stakeholder theory or the assumption that companies have a more proactive approach to implement sustainable purchasing practices as they are aware of the possible benefits. Using a questionnaire survey the companies operating in all sub-sectors of the forest-based industry - wood, pulp and paper and furniture manufacturing, including their suppliers of wood raw material in Slovakia, were questioned with the aim to identify the reasons for implementing sustainable purchasing practices. Findings & Value added: Data obtained are used to identify the factors that are crucial for the introduction of green purchasing in companies in dependence on the specific company characteristics and conditions of the market environment under which companies operate.


Author(s):  
Andrey V. Cherechukin ◽  

The article provides an analysis of key trends in the international market, using the example of the countries of Northeast Asia. In 2019, the world coal market amounted to 1,424.5 million tons, of which 78.1% are energy grades to produce electricity and heat, and 21.9% are in metallurgy, the reserves of which are significantly less. The import coal market of the countries of Northeast Asia in 2019 was already 680 million tons, covering 48% of the entire world coal market. The paper provides an overview of the key importers and exporters of coal in the world, the quantitative and qualitative characteristics of the supplied raw materials, and analyzes the key factors affecting the pricing of coal. In the conclusions, the main trends in the international coal market of the countries of Northeast Asia are presented, including "geographical" — the shift of the center of world trade from Europe to Asia, and "types and quality of imported coal" — an increase in the share of high-quality premium energy and coking (metallurgical). Trends can be clearly seen in the countries of Northeast Asia, which actively use coal, and are making efforts to decarbonize their national economies, while intensifying inter-fuel competition with other primary energy sources.


Author(s):  
Б.Т. Базарова ◽  
Б.Қ. Копбулсынова ◽  
Ж.А. Аймешева ◽  
B. Bazarova ◽  
B. Kopbulsynova ◽  
...  

Батыс Қазақстан облысындағы кәсіпорындардың эволюциясы экономикалық дамудың жалпы циклдік сипатына байланысты да, әр түрлі сыртқы және ішкі факторлардың осы салаға әсер етуінен, сондай-ақ даму процесінде сөзсіз ауытқулар салдарынан ауытқуларға ұшырайды. Батыс Қазақстан облысының аймақтық агроөнеркәсіптік кешенін тұрақты дамытудың басымдықтары талдау арқылы анықталуы керек. Зерттеудің мақсаты - Батыс Қазақстан облысының агроөнеркәсіптік кешенінің тиімді және тұрақты дамуын зерттеу болып табылады. Бұл тақырыпты зерттеу кезінде статистикалық-экономикалық әдіс, талдау және синтез қолданылды. Ауылшаруашылық кешенінің жеке аймақ ретінде тұрақты дамуы да, жалпы елдің де дамуы ауылшаруашылық кешенінің тұрақты қалыптасуынсыз мүмкін емес, себебі оның түпкі өнімі қайта өңдеу өнеркәсібі болып табылады, ал оның мақсаты - талаптарына сай халықты сапалы өніммен қамтамасыз ету. Талдау көрсеткендей, ауылшаруашылық өндірісінің қазіргі жағдайы, қолайсыз факторлардың әсерінің күшеюімен сипатталады, ең алдымен табиғи факторлардың өндірісінде, жалпы өсімдік шаруашылығы өнімінің жылдық айырмашылықтарын тудырады, және өз кезегінде мал шаруашылығындағы ауытқуларға әкеледі, сонымен қатар оның әсері өңдеуші салаларда сезіледі, ал бұл өнеркәсіптің шикізаты болып табылады. Зертеу барысында 2015 жылдан бастап Батыс Қазақстан облысының аумағында ауыл шаруашылығы өнімдері өндірісінің күрт төмендегені анықталды, бұл жалпы, сондай-ақ өсімдік шаруашылығы мен мал шаруашылығы салалары бойынша да өндіріс тұрақтылығының төмендеуіне әкелді, және ол бүгінгі күнге дейін жалғасуда. Агроөнеркәсіптік кешеннің шикізат саласындағы өндіріс тұрақтылығының төмендеуі қайта өңдеу өнеркәсібі өнімдерін өндіруде ауытқулардың артуына әкеліп соқтырды, бұның нәтижесінде халыққа азық-түлік өнімдерін ұсынуда тұрақсыздық пайда болды. Батыс Қазақстан облысының АӨК-ін оның салаларының өнімділігі мен кірістілігін арттыруға бағытталған одан әрі дамыту өндірісті жаңғыртуды және қайта жарақтандыруды, оның инфрақұрылымын дамытуды және салалық кластерлерді қалыптастыруды талап етеді. Кілт сөздер: агроөнеркәсіп кешені, тербеліс, аграрлық сектор, өндіріс, халық саны, агротехника, экономика, талдау, өнімдер, өсімдік шаруашылығы. The evolution of enterprise in the West Kazakhstan region is subject to fluctuations due to both the general cyclical nature of economic development and the impact of various external and internal factors on this industry, as also fluctuations unavoidable in the evolution process. The priorities for sustainable evolution of the regional agro-industrial complex of the West Kazakhstan region should be identified through analysis. The goal of the research is to study the effective and sustainable development of the agro-industrial complex of the West Kazakhstan region. Through studies this topic, the statistical-economic method, analysis and synthesis were used. Sustainable development of the agro-industrial complex of both a particular region and the country as a whole is impossible without the stable functioning of its core - agriculture, the final product of which is used by the processing industry, whose goal is to provide the population with high-quality products in volumes that meet their requirements. Current state of agricultural production, as the analysis shows, is characterized by an increase in the influence of unfavorable factors on production, first of all natural ones, which cause annual differences in the production of gross crop production, which, in turn, convey fluctuations to the livestock industry and, as a result, affects the processing industries. it is the raw material of the industry. In the course of the study, it was found that, since 2015, in the territory of the West Kazakhstan region, there has been a sharp decline in agricultural production, which led to a decrease in the stability of production in general, and in the fields of crop and livestock production, which continues to the present. A decrease in the sustainability of production in the raw materials sector of the agro-industrial complex entailed an increase in fluctuations in the production of products of the processing industry, which ultimately resulted in the emergence of an instability in the supply of food to the population. Further development of the agro-industrial complex of the West Kazakhstan region, aimed at increasing the productivity and profitability of its industries, requires the modernization and re-equipment of production, the development of its infrastructure and the formation of industry clusters.


Author(s):  
Colleen Cunningham ◽  
Il-Yeol Song

Customer relationship management (CRM) is a strategy that integrates concepts of knowledge management, data mining, and data warehousing in order to support an organization’s decision-making process to retain long-term and profitable relationships with its customers. Key factors for successfully implementing CRM (e.g., data quality issues, organizational readiness, customer strategies, selection of appropriate KPIs, and the design of the data warehouse model) are discussed with the main thrust of the chapter focusing on CRM analyses and the impact of those analyses on CRM data warehousing design decisions. This chapter then presents a robust multidimensional starter model that supports CRM analyses. Additional research contributions include the introduction of two new measures, percent success ratio and CRM suitability ratio by which CRM models can be evaluated, the identification/ classification of CRM queries, and a preliminary heuristic for designing data warehouses to support CRM analyses.


2020 ◽  
Vol 8 ◽  
Author(s):  
Duygu Karabelli ◽  
Steffen Kiemel ◽  
Soumya Singh ◽  
Jan Koller ◽  
Simone Ehrenberger ◽  
...  

The growing number of Electric Vehicles poses a serious challenge at the end-of-life for battery manufacturers and recyclers. Manufacturers need access to strategic or critical materials for the production of a battery system. Recycling of end-of-life electric vehicle batteries may ensure a constant supply of critical materials, thereby closing the material cycle in the context of a circular economy. However, the resource-use per cell and thus its chemistry is constantly changing, due to supply disruption or sharply rising costs of certain raw materials along with higher performance expectations from electric vehicle-batteries. It is vital to further explore the nickel-rich cathodes, as they promise to overcome the resource and cost problems. With this study, we aim to analyze the expected development of dominant cell chemistries of Lithium-Ion Batteries until 2030, followed by an analysis of the raw materials availability. This is accomplished with the help of research studies and additional experts’ survey which defines the scenarios to estimate the battery chemistry evolution and the effect it has on a circular economy. In our results, we will discuss the annual demand for global e-mobility by 2030 and the impact of Nickel-Manganese-Cobalt based cathode chemistries on a sustainable economy. Estimations beyond 2030 are subject to high uncertainty due to the potential market penetration of innovative technologies that are currently under research (e.g. solid-state Lithium-Ion and/or sodium-based batteries).


2017 ◽  
Vol 37 (8) ◽  
pp. 757-764 ◽  
Author(s):  
Yubi Ji ◽  
Zhao Yang ◽  
Min Shi ◽  
Hong Tan

Abstract The gelation process of poly(vinyl chloride) (PVC) plastisol is very important to ensure the quality of the product and is affected by the type of resins, plasticizers, and other additives. In this study, the gelation process of the as-prepared PVC plastisol was characterized by measuring the evolution of vibrational viscosity with temperature or time using a vibrational viscometer. Furthermore, the effect of some commercial resins with different particulate morphologies on the gelation process was investigated by synchronously combining scanning election microscopy and laser particle size analyses. The results of this study proved that the particle size distribution and the aggregation degree of the secondary particles of a resin are the key factors affecting the gelation process. For the resin with bimodal particle size distribution, the closer the aggregation of the secondary particles, the slower the gel speed; however, an opposite behavior was observed for the resins with unimodal particle size distribution.


Sign in / Sign up

Export Citation Format

Share Document