scholarly journals An improved method for determining the mass fraction of calcium carbonate in the carbonate bedrock

10.5219/1591 ◽  
2021 ◽  
Vol 15 ◽  
pp. 877-890
Author(s):  
Tatiana Kos ◽  
Inha Kuznietsova ◽  
Tamila Sheiko ◽  
Liubomyr Khomichak ◽  
Yuliia Kambulova ◽  
...  
Keyword(s):  
Calcium Carbonate ◽  
Material Balance ◽  
Component Composition ◽  
Magnesium Carbonate ◽  
Maximum Energy ◽  
Environmental Friendliness ◽  
Complete Chemical Analysis ◽  
Carbonate Material ◽  
Definition Of

In the article it is offered to enter in the technological audit of the lime department of sugar factory the adjusted technique of the definition of the maintenance of calcium carbonate in carbonate breed. For this purpose, a complete chemical analysis of limestone was performed, which includes determination of moisture content, impurities insoluble in hydrochloric acid, the amount of one and a half oxides of aluminum and iron, calcium carbonate (advanced method), and magnesium carbonate, calcium sulfate, alkali metal oxides, potassium, and sodium. The obtained experimental data are summarized in one table and the material balance of all components of carbonate bedrock is summarized. The proposed method made it possible to obtain objective data on the component composition of the carbonate material. This, in turn, avoids many technological problems, namely to reduce the formation of melts in the lime kiln, improve the filtration of juices, increase the ability of lime to chemically interact with water, reduce the volume of water on the juicer etc. Thus, the use of the recommended method for determining calcium carbonate (CaCO3), as part of the technological audit, will allow early adjustment of the process, which will give maximum energy and resource savings, as well as increase the level of environmental friendliness of the enterprise.

Improving the method of determining the mass fraction of magnesium carbonate and the study of the chemical composition of carbonate rocks for the effective conduct of the technological process of sugar production

10.5219/1620 ◽  
2021 ◽  
Vol 15 ◽  
pp. 901-916
Author(s):  
Tatiana Kos ◽  
Inha Kuznietsova ◽  
Tamila Sheiko ◽  
Liubomyr Khomichak ◽  
Larysa Bal-Prylypko ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Technological Process ◽  
Carbonate Rock ◽  
Material Balance ◽  
Component Composition ◽  
Magnesium Carbonate ◽  
Real Component ◽  
Lime Kiln

The article considers an improved method for determining the content of magnesium carbonate in the carbonate rock. An adjusted method for determining the content of magnesium carbonate was included in the complete establishment of chemical analysis of limestone, which includes the determination of moisture, impurities insoluble in hydrochloric acid, the amount of one and a half oxides of aluminum and iron, calcium carbonate and magnesium carbonate (advanced method), calcium sulfate, alkali metal oxides of potassium and sodium. The obtained experimental data were entered into a single table and summed up the material balance of all components of the carbonate rock. As a result, it was found that this technique includes the following criteria: it is the most accurate, most accessible, and cheap. The use of adjusted methods for determining the content of calcium and magnesium carbonate in limestone will make it possible to establish the objective chemical composition of the carbonate rock and avoid several technological problems. Namely, the excess of uncontrolled magnesium carbonate contributes to the formation of the liquid phase, which in turn reduces the concentration of chemically active lime and promotes the formation of melts in the lime kiln, deteriorating filtration rates, clogging the evaporating station, and so on. Therefore, having information about the real component composition of limestone, the technologist will be able to adjust the technological process in advance, which will lead to the preservation of natural resources while the quality of finished products will not decrease.

scholarly journals CONVERSION CALCIUM CARBONATE AS FILLER OF THERMOPLASTICS

2017 ◽  
Vol 60 (4) ◽  
pp. 100 ◽  
Author(s):  
Lyudmila V. Rudakova ◽  
Sabukhi I. Niftaliev ◽  
Ekaterina S. Natarova
Keyword(s):  
Calcium Carbonate ◽  
Aqueous Extract ◽  
Chemical Properties ◽  
Total Content ◽  
Component Composition ◽  
Water Soluble ◽  
Preliminary Heat Treatment ◽  
Crushed Material ◽  
Wide Range

X-ray and laser diffraction methods were used to determine basic physical and chemical properties of conversion calcium carbonate. It was found that for obtaining standard product for use as a filler, it is necessary to regrind it. The results of dispersion changes in conversion chalk (chalk stone) were expressed in terms of median (D50), maximum (D98) and minimum (D10) particle size. It was established that during the grinding process a transition occurs from the initial odiomodal distribution to the bimodal distribution, which is characterized by a sufficiently wide range of the sizes of the particles of the crushed material. The optimum parameters of grinding were determined. With the help of SEM method, used before and after grinding of conversion calcium carbonate, it was established that the particles of primary material are represented by polycrystalline dense aggregates of spherical shape, due to mass crystallization of calcium carbonate at the condition of high supersaturation according to polynuclear growth mechanism. The component composition of water-soluble impurities was quantitatively estimated on the basis of the determination of the content of nitrate N-NO3- and ammonium N-NH4+ forms of nitrogen in various forms of presence-total, bound, water-soluble, and additional determination of the Ca2+ content of calcium ions in aqueous extract. It has been experimentally established that preliminary heat treatment of conversion calcium carbonate allows to significantly reduce the total content of water-soluble substances in the ground product by more than 5 times: at a temperature of 400 ° C, the degree of removal by NH4+ and NO3- ions is ~ 40-50%, and at 500 ° C - ~ 60% for NO3- and ~ 90% for NH4+. The estimation of the possibility of using the obtained product as a filler of polymer composite materials was done comparing the main parameters (CIELab  (W and L) color characteristics, bulk density, dispersed composition, specific surface, pH of aqueous extract) with known finely ground natural chalk and microcalcite. Forcitation:Rudakova L.V., Niftaliev S.I., Natarova E.S. Conversion calcium carbonate as filler of thermoplastics. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2017. V. 60. N 4. P. 100-107.

scholarly journals Colorimetric Determination of Selenium in Mineral Premixes

1997 ◽  
Vol 80 (4) ◽  
pp. 709-716
Author(s):  
Jeffrey A Hurlbut ◽  
Roger G Burkepile ◽  
Carolyn A Geisler ◽  
Philip James Kliak ◽  
Nathan G Rummel
Keyword(s):  
Calcium Carbonate ◽  
Sodium Selenite ◽  
Ethylenediaminetetraacetic Acid ◽  
Base Material ◽  
Magnesium Carbonate ◽  
Sodium Selenate ◽  
Colorimetric Determination ◽  
Sample Type ◽  
Coefficients Of Variation

Abstract A method is described for determination of sodium selenite or sodium selenate in mineral-based premixes. It is based on the formation of intense-yellow piazselenol by Se(IV) and 3,3’-diaminobenzid- ine. Mineral premixes typically contain calcium carbonate as a base material and magnesium carbonate, silicon dioxide, and iron(lll) oxide as minor components or additives. In this method, the premix is digested briefly in nitric acid, diluted with water, and filtered to remove any iron(lll) oxide. Ethylenediaminetetraacetic acid and HCI are added to the filtrate, which is heated to near boiling for 1 h to convert any selenate to selenite. After heating, the solution is buffered between pH 2 and 3 with NaOH and formic acid and treated with NH2OH and EDTA; any Se present forms a complex with 3,3’- diaminobenzidine at 60°C. The solution is made basic with NH4OH, and the piazselenol is extracted into toluene. The absorbance of the complex in dried toluene is measured at 420 nm. The method was validated independently by 2 laboratories. Samples analyzed included calcium carbonate fortified with 100, 200, and 300 μg Se in the form of sodium selenite or sodium selenate, a calcium carbonate premix containing sodium selenite, a calcium carbonate premix containing sodium selenate, and a commercial premix; 5 replicates of each sample type were analyzed by each laboratory. Average recoveries ranged from 89 to 109% with coefficients of variation from 1.2 to 13.6%.

scholarly journals Improvement of the scheme analysis of the component composition of a larch wood

2020 ◽  
Author(s):  
Э.И. Евстигнеев
Keyword(s):  
Component Composition ◽  
Water Soluble ◽  
Special Equipment ◽  
Component Structure ◽  
Wood Component ◽  
Extractive Substances ◽  
Definition Of ◽  
Quantitative Definition ◽  
Scheme Analysis

Разработана схема анализа компонентного состава лиственницы, предусматривающая определение таких компонентов, как полисахариды, целлюлоза, нецеллюлозные полисахариды, лигнин, экстрактивные вещества и зола. В отличие от известных схем анализа химического состава древесины, она содержит новую стадию, а именно определение общего содержания полисахаридов фотоколориметрическим методом. Обычно для этой цели используют определение холоцеллюлозы, однако известные методы не позволяют выделить все полисахариды, поскольку в процессе выделения часть из них неизбежно утрачивается. Зная общее содержание полисахаридов, можно определить содержание нецеллюлозных полисахаридов. Такой подход имеет явное преимущество, по сравнению с традиционно используемым определением отдельно гемицеллюлоз и отдельно водорастворимых полисахаридов, так как в этом случае происходит потеря части полисахаридов. Предложенная схема дает возможность достаточно полно охарактеризовать компонентный состав древесины лиственницы, не прибегая к использованию специального оборудования. Разработанный метод определения арабиногалактана обладает высокой селективностью к определяемому компоненту древесины в присутствии большого количества примесей, в связи с чем он может быть рекомендован для количественного определения арабиногалактана как в водных растворах, так и в древесине. The scheme of the analysis of component structure of a larch providing determination of such components as polysaccharides, cellulose, not cellulose polysaccharides, lignin, extractive substances and ashes is developed. Unlike the known schemes of the analysis of the chemical composition of wood, it contains a new stage, namely determination of the general content of polysaccharides by a photocolorimetric method. Usually, for this purpose use definition of a holocellulose, however the known methods do not allow to emit all polysaccharides as in the course of allocation part of them is inevitably lost. Knowing the general content of polysaccharides, it is possible to determine the content of not cellulose polysaccharides. Such approach has clear advantage in comparison with traditionally used determination separately of hemicelluloses and separately water-soluble polysaccharides since in this case there is a loss of a part of polysaccharides. The scheme offered in work, gives the chance rather fully to characterize component composition of wood of a larch, without resorting to use of the special equipment. The developed method of an arabinogalactan determination has high selectivity to the defined wood component in the presence of a large amount of impurity in this connection it can be recommended for quantitative definition of an arabinogalactan both in water solutions, and in wood.

Features of determination of native carbon in carbon-containing rocks on the analyzer of carbon and water

2021 ◽  
Vol 87 (7) ◽  
pp. 23-29
Author(s):  
N. A. Feoktistov ◽  
V. Р. Chernov ◽  
К. G. Pivovarova ◽  
Т. В. Ponamareva ◽  
I. V. Mikhalkina
Keyword(s):  
Calcium Carbonate ◽  
Bound Water ◽  
Magnesium Carbonate ◽  
Carbonate Content ◽  
South Urals ◽  
Temperature Range ◽  
Burn Out ◽  
Carbon Determination ◽  
Ir Spectroscopic

The largest deposits of graphite in the Russian Federation are located in the Middle and South Urals. However, several manifestations, e.g., «Opytnyi» sector, which have not yet been placed under production, require substantiation of the strategies for their integrated development, which, in turn, requires gaining the reliable data on the content of graphite in carbon-containing rocks. A method for simultaneous determination of organic and native carbon in carbon-containing rocks using an ELTRA CW MULTIPHASE carbon and water analyzer is proposed. The method is based on the combustion of organic carbon (coal, shale) in a stream of oxygen at 550°C and native carbon (graphite) in the temperature range 550 – 1000°C with subsequent IR-spectroscopic determination of the content of gaseous carbon dioxide. The interfering effect of magnesium carbonate and calcium carbonate on the determination of organic and native carbon was taken into account in the calculations. The carbonate content was determined using a separate sample in a nitrogen flow by decomposition of magnesium carbonate at 550°C and calcium carbonate within a temperature range of 550 – 1000°C. The content of chemically bound water in the composition of the minerals of carbon-containing rocks, was determined simultaneously with carbon. The only one type of carbon — graphite — was observed in the studied samples of the carbon-containing rock from «Opytnyi». The different combustion capacity of graphite was revealed: some of the crystals almost completely burn out at a temperature below 800°C and others above 800°C, which suggests the presence of cryptocrystalline and explicit crystalline graphite in the rocks. The developed method is rapid and corresponds in accuracy to the method for native carbon determination ±0.27 C % – 0.01 C % developed and approved by the Research Council for Analytical Methods of Research (NSAM).

State Failure and the Political Violence Phenomenon: A Comparative Analysis of Iraq and Syria Cases

2016 ◽  
Vol 4 (2) ◽  
pp. 170 ◽  
Author(s):  
K. Eylem Özkaya Lassalle
Keyword(s):  
Cold War ◽  
Political Violence ◽  
State Failure ◽  
The Political ◽  
Collective Violence ◽  
Short Run ◽  
Definition Of ◽  
The Cold War

The concept of failed state came to the fore with the end of the Cold War, the collapse of the USSR and the disintegration of Yugoslavia. Political violence is central in these discussions on the definition of the concept or the determination of its dimensions (indicators). Specifically, the level of political violence, the type of political violence and intensity of political violence has been broached in the literature. An effective classification of political violence can lead us to a better understanding of state failure phenomenon. By using Tilly’s classification of collective violence which is based on extent of coordination among violent actors and salience of short-run damage, the role played by political violence in state failure can be understood clearly. In order to do this, two recent cases, Iraq and Syria will be examined.

DEFINITION OF TIME SPENT ON REPAIR OF BUS TRANSMISSION UNITS TAKING INTO ACCOUNT TECHNOLOGICAL EQUIPMENT RELIABILITY

2020 ◽  
Vol 2020 (9) ◽  
pp. 29-33
Author(s):  
Sergey Bulatov
Keyword(s):  
Negative Impact ◽  
Probabilistic Method ◽  
Technological Equipment ◽  
Quality And Safety ◽  
Transmission Unit ◽  
Equipment Reliability ◽  
Hours Of Work ◽  
Definition Of ◽  
Time Decrease

The paper purpose is the effectiveness estimation in the technological equipment use, taking into account its reliability and productivity for defective transmission units of buses. The problem consists in the determination of time to be spent on repair of bus transmission units taking into account technological equipment reliability. In the paper there is used a probabilistic method for the prediction bus transmission units, and also a method of the dynamics of averages which allow ensuring minimum of costs for units downtime during repair and equipment cost. The need for repair of transmission units (gear box) arises on an average after 650 hours, the average productivity of the bench makes 4.2 bus / hour. The bench fails on the average after 4600 hours of work, the average time of the bench makes 2 hours. In such a way the solution of the problem specified allows analyzing the necessity of time decrease for transmission unit repair to avoid long downtimes of buses in repair areas without negative impact upon high repair quality and safety during the further operation.

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