Technology for the production of high-carbon ferrochromium using mono-briquettes

The article presents results of large-scale laboratory studies on the basis of Chemical-Metallurgical Institute named after Zh. Abishev on establishing the possibility of using a mono-charge for smelting standard carbon ferrochromium. Enlarged-laboratory studies were carried out in an ore-thermal furnace with transformer capacity of 200 kVA. Duration of the pilot campaign was 4 days. Three variants of briquettes containing various reducing agents were tested, including: traditional charge (coke PRC + special coke + Borolinsky coal); briquettes with coal from Shubarkol; briquettes with Borlinsky coal; briquettes with coke of China. As a comparative variant, traditional technology with charge materials without briquetting was used. In total, when conducted large-scale laboratory studies it was 41 smeltings. The tests began with a comparative version, which was chosen as technology closest to the technology at Aktobe ferroalloy plant. On the traditional charge, top worked without the uniformly gassing over entire surface of the top. Recovery rate of chromium in the alloy was 79.3 %. Change to briquettes with Shubarkol coal in general has led to the process intensification with more stable current load. The furnace productivity increased to 165.9 kg Cr/day due to increase in the contact surface of reacting phases in briquettes. When using briquettes with Borlinsky coal, satisfactory technological parameters of the smelting process for high-carbon ferrochrome were also obtained, extraction rate of chromium into the metal was 84.91 %. When using briquettes from 0 – 10 mm ore fraction ore and CPR coke in the charge, furnace operation and state of the top were not different from previous periods. The charge also went off evenly, without collapses, the briquettes on the top were not destroyed and current load was highly stable. The work also presents comparative technical and economic indicators for all technologies using mono-charge briquettes.

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Smelting options for carbon ferrochrome based on ore raw materials, middlings and their technological evaluation

Kompleksnoe ispolʹzovanie mineralʹnogo syrʹâ/Complex Use of Mineral Resources/Mineraldik shikisattardy Keshendi Paidalanu ◽

10.31643/2022/6445.06 ◽

2022 ◽

Vol 320 (1) ◽

pp. 51-59

Author(s):

S. Baisanov ◽

◽

Ye.Zh. Shabanov ◽

K.V. Grigorovich ◽

R.T. Toleukadyr ◽

...

Keyword(s):

Large Scale ◽

Raw Materials ◽

Main Idea ◽

Economic Indicators ◽

Processing Plant ◽

Technological Parameters ◽

Gas Cleaning ◽

Carbon Ferrochrome ◽

Technological Evaluation ◽

Technical And Economic Indicators

The article presents the results of large-scale laboratory tests carried out in the conditions of the Chemical and Metallurgical Institute named after V.I. Zh. Abishev on the use of briquetted mono-charge in the smelting of carbon ferrochrome on a 250 kVA furnace. The purpose of these studies was to determine the technological parameters of the use of briquetted mono-charge containing in its composition chrome ore, wastes from the production of high-carbon ferrochrome, middlings and various carbonaceous reducing agents. The main idea of using these briquettes was to multiply the contact surface of the reductant and ore, which should speed up the technological process. The principal possibility of smelting a standard alloy using briquetted mono-charge is shown. The alloy for individual charge options meets the requirements of the standards. In comparison with the technology without the use of briquettes, the mono-charge technology has shown advantages in all main parameters. The technology with the use of briquettes from the dust of the AktZF gas cleaning system is distinguished by a low yield of non-standard metal and slag, the bulk of the material goes into the gas collection system. Technologies from briquettes from fines pellet production area of Donskoy ore mining and processing plant and flash have very low specific technical and economic indicators and cannot be recommended for industrial use. Improvement of briquetting modes and technology of their smelting is required. The technical and economic indicators were higher than the current one, showed briquettes from ore and coke of the People's Republic of China, briquettes of ore from borlin and shubarkol coals of Kazakhstan.

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High-carbon ferromanganese smelting on high-base slags

Kompleksnoe ispolʹzovanie mineralʹnogo syrʹâ/Complex Use of Mineral Resources/Mineraldik shikisattardy Keshendi Paidalanu ◽

10.31643/2020/6445.38 ◽

2020 ◽

Vol 4 (315) ◽

pp. 63-73

Author(s):

O. R. Sariev ◽

◽

M. S. Dossekenov ◽

B. S. Kelamanov ◽

A. M. Abdirashit ◽

...

Keyword(s):

Large Scale ◽

Chemical Properties ◽

Oxide Content ◽

High Carbon ◽

High Carbon Ferromanganese ◽

High Base ◽

Technical And Economic Indicators ◽

Physical And Chemical ◽

Positive Effect ◽

Positive Results

The article presents the results of laboratory trials for the smelting of high-carbon ferromanganese on highly-basic slags. Laboratory trials have confirmed that an increase in the basicity of ferromanganese production slags has a positive effect on the reduction of manganese to the metal and a decrease in the concentration of silicon in it. However, the high basicity makes the slag high-melting and tough, leading to large losses of manganese with the slag. The use of on borate fluxes solves this problem by affecting the physical and chemical properties of the final slags, which allows the process to be carried out at high basicities with the achievement of optimal technological indicators. The obtained positive results of laboratory experiments served as the basis for approbation the developed technology on a semi-industrial scale with the smelting of high-carbon ferromanganese by the flux method from the manganese ore of the «Bogach» Deposit. As a result of studying the smelting of carbonaceous ferromanganese in large-scale laboratory conditions, the possibility of converting manganese ores on highly-basic slags with appropriate regulation of the transport properties of slag to a standard metal with high technical and economic indicators was established. The best results are achieved when the CaO/SiO2 ratio in the slag is 1.8 and the boron oxide content in the slag is 0.8%. It is established that under these conditions, the obtained boron-containing highly-basic slags of carbonaceous ferromanganese are not subject to slaking.

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RECOMMENDATIONS FOR THE CHOICE OF MILKING INSTALLATIONS IN LOOSE HOUSING SYSTEMS OF COWS

Molochnoe i miasnoe skotovodstvo ◽

10.33943/mms.2020.12.24.001 ◽

2020 ◽

Author(s):

В.В. ГОРДЕЕВ ◽

В.Е. ХАЗАНОВ

Keyword(s):

Dairy Cows ◽

High Performance ◽

Large Scale ◽

Dairy Farms ◽

Economic Indicators ◽

Technical Level ◽

Housing Systems ◽

Working Shift ◽

Technical And Economic Indicators

При выборе типа доильной установки и ее размера необходимо учитывать максимальное планируемое поголовье дойных коров и размер технологической группы, кратность и время одного доения, продолжительность рабочей смены дояров. Анализ технико-экономических показателей наиболее распространенных на сегодняшний день типов доильных установок одинакового технического уровня свидетельствует, что наилучшие удельные показатели имеет установка типа «Карусель» (1), а установка типа «Елочка» (2) требует более высоких затрат труда и средств. Установка «Параллель» (3) занимает промежуточное положение. Из анализа пропускной способности и количества необходимых операторов: установка 2 рекомендована для ферм с поголовьем дойного стада до 600 голов, 3 — не более 1200 дойных коров, 1 — более 1200 дойных коров. «Карусель» — наиболее рациональный, высокопроизводительный, легко автоматизируемый и, следовательно, перспективный способ доения в залах, особенно для крупных молочных ферм. The choice of the proper type and size of milking installations needs to take into account the maximum planned number of dairy cows, the size of a technological group, the number of milkings per day, and the duration of one milking and the operator's working shift. The analysis of technical and economic indicators of currently most common types of milking machines of the same technical level revealed that the Carousel installation had the best specific indicators while the Herringbone installation featured higher labour inputs and cash costs. The Parallel installation was found somewhere in between. In terms of the throughput and the required number of operators Herringbone is recommended for farms with up to 600 dairy cows, Parallel — below 1200 dairy cows, Carousel — above 1200 dairy cows. Carousel was found the most practical, high-performance, easily automated and, therefore, promising milking system for milking parlours, especially on the large-scale dairy farms.

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Measuring ignitability for in situ burning of oil spills weathered under Arctic conditions: From laboratory studies to large-scale field experiments

Marine Pollution Bulletin ◽

10.1016/j.marpolbul.2011.05.020 ◽

2011 ◽

Vol 62 (8) ◽

pp. 1780-1785 ◽

Cited By ~ 27

Author(s):

Janne Fritt-Rasmussen ◽

Per Johan Brandvik

Keyword(s):

Large Scale ◽

Field Experiments ◽

Oil Spills ◽

Laboratory Studies ◽

Scale Field ◽

Arctic Conditions ◽

Large Scale Field

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An integrated chemical and technological approach for assessing Portuguese wheat flours quality and lengthening bread shelf-life

Emirates Journal of Food and Agriculture ◽

10.9755/ejfa.2019.v31.i11.2037 ◽

2019 ◽

pp. 884

Author(s):

Fernando Cebola Lidon ◽

Diana Daccak ◽

Paula Scotti-Campos ◽

Maria Manuela Silva ◽

Ana Sofia Bagulho ◽

...

Keyword(s):

Shelf Life ◽

Large Scale ◽

Current Trend ◽

Food Additives ◽

Bread Making ◽

Technological Parameters ◽

Full Characterization ◽

Technological Approach ◽

Industrial Level

The current trend of large-scale bread production is to facilitate processing at an industrial level, considering the use of flour mixtures with different chemical and technological parameters and incorporating food additives. Accordingly, costs can be minimized, whereas the quality and the shelf-life of the final product might increase, but a full characterization of the flours that must be used and the selection of the food additives to be incorporated into the dough is required. In this context, three Portuguese wheat flour varieties were evaluated (FariRamos, Nacional and AJMiranda), as well as two types of food additives with the aim to increase bread shelf-life. In these flours, the levels of K, S, P, Ca and Cl prevailed, but the moisture and ash contents of FariRamos were the highest and lowest, respectively. The colour of all flours was generally within the desired standard values. Nacional flour contained a higher fat content, but all the flours showed a higher relative abundance of linoleic acid (C18:2), followed by palmitic acid (C16:0) and oleic acid (C18:1). AJMiranda flour revealed a higher content of wet gluten and protein, but the SDS sedimentation index showed a higher value in the FariRamos flour. The fall index, which directly monitors the activity of the α-amylase enzyme, showed a lower value in AJMiranda and Nacional. Through farinograph and alveographyc analysis it was found that FariRamos has a tenacious gluten, but AJMiranda and Nacional had a balanced gluten, yet all of them can be classified as medium flours. Bread making with a mix of FariRamos, AJMiranda and Nacional flours and incorporating preservative food additives revealed the highest shelf-life (11-days) with methyl p-hydroxybenzoate [0.05 %] and benzoic acid [0.1 %], but the colour of the breads showed a relationship of intensity of white colour that depended on the additive used. At the end of the shelf-life, molds of the Eurotium, Trichoderma and Cladosporium genera developed in the bread. It was concluded that the chemical and technological approach applied in the characterization of the flour varieties, can be directly used to define the quality and shelf-life in the bakery industry, allowing the establishment of minimum commercialization prices.

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Designs of new operating copper processing plants: process types, equipment selection, industry trends

Obogashchenie Rud ◽

10.17580/or.2021.01.08 ◽

2021 ◽

pp. 44-52

Author(s):

V. F. Baranov

Keyword(s):

Large Scale ◽

High Capacity ◽

Process Intensification ◽

Processing Plant ◽

Advantages And Disadvantages ◽

Sulphide Ores ◽

Flotation Cells ◽

Ore Preparation ◽

Processing Plants ◽

Technical Solutions

The article describes the largest operating processing plants for lowgrade copper sulphide ores of our time: 10 plants using the semi-autogenous grinding (SAG) technology and 10 plants using high-pressure grinding rolls (HPGR), with the output of 18 to 100 Mtpa. The unfavorable natural and economic factors are balanced by improved ore preparation and concentration technologies and high-capacity equipment units, combined with cost-saving layout solutions. The ore preparation sector is currently divided between the competing technologies of semi-autogenous grinding and HPGR. The article contains an overview of their advantages and disadvantages. The world’s largest monosection with the capacity of 55.5 Mtpa, that uses the SAG technology, is described. The role of the Drop Weght Test JKSimMet (A×b) parameter in the selection of the ore preparation method and the trend for using HPGR in the processing of strong ores are shown. Examples are provided for the consequences of an inadequate assessment of the feed strength in SAG-based plant designs. Examples of ore preparation process intensification through the use of HPGR in semi-autogenous grinding circuits are also given. The volume of impeller flotation cells installed has reached 600 m3. An overview of the two largest processing plants of our time with the output of 88 and 100 Mtpa of ore is presented. The innovative technical solutions of a newest low-capacity copper plant are highlighted. Based on the results of the overview, a future processing plant is predicted to use ∅12.8–13 m SAG mills, HPGRs with the roll diameter of 3 m, vertical VTM-7000 mills in ore grinding cycles, large fine screens, large-scale impeller flotation cells, and staged SFR and DFR flotation reactors.

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Study on Fluorine Pollution in a Slag Yard

Applied Sciences ◽

10.3390/app9050847 ◽

2019 ◽

Vol 9 (5) ◽

pp. 847

Author(s):

Lide Wei ◽

Changfu Wei ◽

Sugang Sui

Keyword(s):

Numerical Simulation ◽

Experimental Investigation ◽

Numerical Simulations ◽

Solute Transport ◽

Large Scale ◽

Three Dimensional ◽

Simulation Method ◽

Laboratory Studies ◽

Survey Results ◽

Simulation Results

This paper suggests a large-scale three-dimensional numerical simulation method to investigate the fluorine pollution near a slag yard. The large-scale three-dimensional numerical simulation method included an experimental investigation, laboratory studies of solute transport during absorption of water by soil, and large-scale three-dimensional numerical simulations of solute transport. The experimental results showed that the concentrations of fluorine from smelting slag and construction waste soil were well over the discharge limit of 0.1 kg/m3 recommended by Chinese guidelines. The key parameters of the materials used for large-scale three-dimensional numerical simulations were determined based on an experimental investigation, laboratory studies, and soil saturation of survey results and back analyses. A large-scale three-dimensional numerical simulation of solute transport was performed, and its results were compared to the experiment results. The simulation results showed that the clay near the slag had a high saturation of approximately 0.9, consistent with the survey results. Comparison of the results showed that the results of the numerical simulation of solute transport and the test results were nearly identical, and that the numerical simulation results could be used as the basis for groundwater environmental evaluation.

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The Role of Epidemiological Investigation in the Detection of Environmental Carcinogenic Risks

Tumori Journal ◽

10.1177/030089166805400104 ◽

1968 ◽

Vol 54 (1) ◽

pp. 23-46

Author(s):

Rodolfo Saracci ◽

Umberto Veronesi

Keyword(s):

Large Scale ◽

Retrospective Studies ◽

Space Distribution ◽

Epidemiological Methods ◽

Laboratory Studies ◽

Cancer Etiology ◽

Common Basis ◽

Time Space ◽

Morbidity Data

An introductory review is presented of the uses and limitations of epidemiological methods for investigating cancer etiology. Uses of epidemiological methods can be grouped under three main headings: search af etiological indications, test of etiological hypotheses, and assessment of the effect of large scale prophylactic or therapeutic treatments. The search of etiological indications is chiefly performed through an analysis of mortality and/or morbidity data: time and space distribution of cancers are usually studied and sometimes an investigation on time-space association is added. On this basis etiological hypotheses are formulated and tested using retrospective studies and/or prospective studies: typical examples of these are found in oncological literature. Assessment of the effect of large scale prophylactic or therapeutic treatments, where feasible, is a further check on the soundness of an etiological hypothesis. Limitations intrinsic to the epidemiological approach (as to any merely observational approach) can be partly overcome through close linkage between epidemiologic and experimental oncology; use of mathematical models to interpret on a common basis data from epidemiological and laboratory studies can make easier this task.

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