scholarly journals PRODUCTION OF NON-ROASTING PELLETS FROM THE WASTE OF SHABROVSKY TALCUM COMBINE

2019 ◽  
Vol 62 (3) ◽  
pp. 201-207
Author(s):  
V. S. Gulyakov ◽  
A. S. Vusikhis ◽  
S. A. Petrova

Technogenic wastes are by-products of any production. At the same time, they can be a raw material for obtaining useful products. In particular, the waste from the Shabrovsky talcum combine, can be used to produce magnesian fluxes. They are dispersed, so must be agglomerated. Therefore, a method has been proposed for the preparation of non-roasting pellets. As a binder, a mixture of water and peat, treated in a hydropercussion cavitation device, was used. The resulting material is a colloidal system with particle size of less than 10–4 m. To measure the particle size, dynamic light scattering method was used. For comparison, a similar mixture of water and peat treated in a planetary mill was studied. An analysis of the data obtained has shown that particles of micron size occupy up to 90 % of volume in the sample after treatment of the mixture in hydropercussion cavitation device. In a sample that was ground in a planetary mill, most of the particles are characterized by tens or even hundreds of microns. Determination of crushing strength of non-roasting pellets is performed by compressing in a tensile machine of model P-0.5. For this purpose, the granules were used both immediately after granulation and after drying at 105 °C to a moisture content of less than 1.5 %. With an optimum proportion of binders of 15 – 20 %, the strength of raw pellets was 15 N, and the strength of dry pellets was 90 N. With a binder percentage of less than 15 %, both raw and dried pellets had low strength. With a binder content of more than 20 %, the mixture had excessive plasticity and tackiness, which led to the formation of conglomerates of several granules. Despite the fact that the strength parameters of the non-roasting pellet are lower than those of pellets used in blast-furnace production, they are sufficient for use in steelmaking processes.

2019 ◽  
Vol 18 (03n04) ◽  
pp. 1940032 ◽  
Author(s):  
V. N. Kuryakov ◽  
D. D. Ivanova

Stable emulsions of individual n-alkane (n-nonadecane) in water with different average particle size were prepared without surfactants. The phase transition temperatures for n-nonadecane were determined by the dynamic light scattering method. The effect of the n-alkane particle size on the melting and crystallization temperatures was studied. The crystallization temperature significantly decreases for particles smaller than a certain characteristic value.


2012 ◽  
Vol 8 (1) ◽  
pp. 123-132 ◽  
Author(s):  
Zsuzsanna Horváth ◽  
Béla Marosvölgyi ◽  
Christine Idler ◽  
Ralf Pecenka ◽  
Hannes Lenz

Abstract - There are several problems in storing wood chips freshly harvested from short rotation plantations, which result in quality losses as well as in dry matter and energy losses. The factors influencing the degradation of raw material are examined in this paper with special focus on fungal development. An excessive growth of fungi is connected to dry matter losses and also to an increased health risk during raw material handling. The following factors were measured during 6 months storage of poplar wood chips depending on particle size: box temperature, moisture content, pH-value, appearance of fungi in the storage and the concentration of fungal particles in the air. The results show a close connection between particle size, temperature and attack of fungi. During the storage mesophilic and termophilic species of the genera Alternaria, Aspergillus, Cladosporium, Mucor and Penicillium appeared. The concentration of fungal particles is the highest for fine chips and decreases in bigger particles. There was a special focus on the investigation of the properties of coarse chips (G 50), which represent a good compromise between handling, storage losses and health risk due to fungal development.


2015 ◽  
Vol 670 ◽  
pp. 49-54 ◽  
Author(s):  
Yuriy A. Zaharov ◽  
Valeriy M. Pugachev ◽  
Kseniya A. Datiy ◽  
Anna N. Popova ◽  
Anastasiya S. Valnyukova ◽  
...  

In the paper, the particle morphology is considered and the slices of phase diagrams of nanosystems agreeable to the synthesis conditions are constructed according to the data obtained earlier by authors, as well as new results of the study of nanostructured Fe-Co, Fe-Ni, Co-Ni, Fe-Co-Ni, Fe-Pt, Cu-Ni and Ni-Cd powders. It is found that all considered polymetallic systems have common nature of the particle size spatial organization, i.e., 7-20 nm nanocrystals (for different systems) form highly compact aggregates (40-100 nm) which put together into loose porous agglomerates (up to 200-250 nm) and then into unconsolidated micron size formation of cloud type. It is classified uncovered features of nanostructured polymetallic phase diagrams in comparison with phase diagrams of bulk systems. Magnetic properties of nanosystems are studied.


Processes ◽  
2020 ◽  
Vol 8 (11) ◽  
pp. 1416
Author(s):  
Małgorzata Miastkowska ◽  
Agnieszka Kulawik-Pióro ◽  
Mariola Szczurek

Background: Despite the variety of treatment methods for wounds and scars after burns, there are still few effective preparations that can be used in a non-invasive therapy. Recent years have seen significant development of nanomedicine and nanotechnology in the treatment of infection in burn wounds. Proposal: The aim of this work was to develop a formula of a nanoemulsion gel for skin regeneration after burns, and to compare its rheological and sensory properties, as well as the effectiveness of post-burn skin regeneration with preparations available on the market. Methods: At the first stage of studies the composition and parameters of the preparation of sea buckthorn oil-based O/W (oil-in-water) nanoemulsion containing hyaluronic acid and aloe vera gel, as the active ingredients were optimized. Then, the nanoemulsion was added to the gel matrix composed of carbomer (1%) and water which resulted in receiving nanoemulgel. The physicochemical parameters of the obtained samples were characterized by means of dynamic light scattering method and scanning electron microscope. Rheological, sensory and influence on skin condition analysis was conducted for selected market products and developed nanoemulgel. Results: Nanoemulsion gel (d = 211 ± 1.4 nm, polydispersity index (PDI) = 0.205 ± 0.01) was characterized by semi-solid, non-sticky consistency, porous structure, law viscosity, good “primary” and “secondary” skin feelings and pleasant sensorical properties. It improves the condition of burned skin by creating a protective layer on the skin and increasing the hydration level. Conclusion: Due to the fact that the obtained nanoemulsion gel combines the advantages of an emulsion and a gel formulation, it can be a promising alternative to medical cosmetics available on the market, as a form of formulation used in skin care after burns.


2020 ◽  
Vol 1012 ◽  
pp. 233-238
Author(s):  
Vanessa Moura de Souza ◽  
Vinícius Martins ◽  
Rejane Maria Candiota Tubino

This paper evaluated the use of the pitcher, a ceramic waste obtained through the quality process of a sanitary ware industry, in the development of a material for usage in the manufacture of sintered parts. The pitcher was obtained through powder technology and is composed, according to the chemical analysis obtained by X-ray fluorescence spectrometry, of clayey minerals (clay and kaolin), quartz, and feldspar, which may include ceramic rocks such as granite, pegmatite and phyllite; that is, it has proved to be a potential raw material due to the minerals that can still be reused. The pitcher passed through a granulometry-based selection process, sieving about 20kg using the following sieve sequence: 18 MESH, 25 MESH, 30 MESH, 120 MESH and 400 MESH; with around 70% of the residue being retained in the sieves of 120 and 400 MESH, which were selected to be used in the evaluation. The samples were compacted in a manual press with different pressures, between 300 and 1000 kgf, and after were sintered at a temperature of 1100oC in a resistive furnace. To characterize the material, the apparent and green density, as well as the compressibility curve, were determined to identify the best compression pressure. The microstructure of the test specimen and the pitcher homogeneity were evaluated using Scanning Electron Microscopy (SEM). Both particle sizes presented the typical compressibility curve, in which the density increases with increasing compaction pressure, while the curve slope decreases with increasing pressure. The density increase with the increasing compaction pressure indicates a good densification for the temperatures, independent of the sample granulometry. The sintering porosity decreased proportionally to the particle size in the sintered samples. The analysis showed that the particle size of 400 MESH sintered at 1100oC obtained more porous surfaces, thus indicating a promising future for the manufacture of parts using powder technology, especially for the development of filters.


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