Particular Oxydation Features of Various Mechanical Strength Cokes

2019 ◽  
Vol 946 ◽  
pp. 486-492
Author(s):  
V.I. Matyukhin ◽  
S.Ya. Zhuravlev ◽  
A.V. Khandoshka
Keyword(s):  
High Temperature ◽  
Heat Generation ◽  
Gas Permeability ◽  
Combustion Products ◽  
Charge Material ◽  
Reactivity Index ◽  
Generation Process ◽  
Charge Component ◽  
Scanning Calorimetry ◽  
Coke Strength

Lump solid fuel is one of the most important charge material components in layered cupola units. It determines layer gas permeability, conditions development for heat exchange with gasses in it, heat generation process rate and intensity. In present-day conditions of material shaft melting charge materials of boosted fractional makeup are used, as well as oxygen, carbon and hydrogen enriched air. In the circumstances the issue of ensuring the best gas dynamic conditions become particularly vital, both for the furnace low and high temperature zones, at the charge component oxidation and recovery processes development. Under conditions of continuous charge component movement in the layered unit workspace they are subjected to abrasive action of charge components with the result, which may be described by mechanical properties based on mass yield of certain fractions after disruption in a closed drum М10 and М40. Coke lump behavior at relatively high temperature (below 1100°С) in the presence of complete fuel combustion products СО2 and Н2О may be implicitly evaluated by coke strength after reaction (CSR) and coke reactivity index (CRI). When studying, particular combustion features of coal coke in conditions close to shaft cupola unit operation data of the total differential scanning calorimetry (DSC) curve were used. Temperature ranges of intensive heat generation were determined from the beginning of active coke sample oxidation to completion of the burnout period, as well as apparent heating capacity and coke combustion thermal effect.

Effect of Hydro-Thermal Treatment with CaO Addition on the Coking Properties of Shengfu Coal

2011 ◽  
Vol 236-238 ◽  
pp. 835-838 ◽  
Author(s):  
Hua Zhou ◽  
Hong Tao Chang ◽  
Heng Fu Shui ◽  
Zhi Cai Wang ◽  
Chang Hui Lin ◽  
...  
Keyword(s):  
Thermal Treatment ◽  
Gas Permeability ◽  
Reactivity Index ◽  
Metallurgical Coke ◽  
Strength Index ◽  
Coke Strength ◽  
Coke Reactivity ◽  
Coking Properties ◽  
Different Temperatures ◽  
Coke Strength After Reaction

Shengfu (SF) coal was hydro-thermally treated with and without CaO addition at different temperatures and the crucible coking determinations were carried out to evaluate the effects. The results show that hydro-thermal treatment can obviously increase the micro-strength index (MSI) of the coke and particle coke strength after reaction (PSR), and decrease particle coke reactivity index (PRI), which are beneficial for metallurgical coke to increase the gas permeability in blast furnace. Addition of CaO during hydro-thermal treatment at 150-250°C greatly promotes the effects of hydro-thermal treatment. However, hydro-thermal treatment at 300°C with CaO results in dramatic decrease in MSI and PSR due to the enhanced hydrolysis reactions at this temperature by CaO to form strong cross-linking in the treated coal.

MANIFLEX-FM

Alloy Digest ◽  
1974 ◽  
Vol 23 (2) ◽  
Keyword(s):  
Stainless Steel ◽  
Corrosion Resistance ◽  
High Temperature ◽  
Austenitic Stainless Steel ◽  
Heat Treating ◽  
Combustion Products ◽  
High Temperature Strength ◽  
Automotive Engines ◽  
Good Corrosion Resistance ◽  
Temperature Performance

Abstract MANIFLEX-FM is a free-machining chromium-nickel austenitic stainless steel which offers excellent high-temperature strength and hardness with good corrosion resistance to combustion products. It is widely used exhaust components in automotive engines. This datasheet provides information on composition, physical properties, elasticity, and tensile properties. It also includes information on high temperature performance and corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: SS-291. Producer or source: Carpenter.

scholarly journals Demonstration of Phase Change Thermal Energy Storage in Zinc Oxide Microencapsulated Sodium Nitrate

2021 ◽  
Vol 11 (13) ◽  
pp. 6234
Author(s):  
Ciprian Neagoe ◽  
Ioan Albert Tudor ◽  
Cristina Florentina Ciobota ◽  
Cristian Bogdanescu ◽  
Paul Stanciu ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Thermal Properties ◽  
High Temperature ◽  
Energy Storage ◽  
Phase Change ◽  
Thermal Energy ◽  
Sodium Nitrate ◽  
Thermal Energy Storage ◽  
Metal Corrosion ◽  
Scanning Calorimetry

Microencapsulation of sodium nitrate (NaNO3) as phase change material for high temperature thermal energy storage aims to reduce costs related to metal corrosion in storage tanks. The goal of this work was to test in a prototype thermal energy storage tank (16.7 L internal volume) the thermal properties of NaNO3 microencapsulated in zinc oxide shells, and estimate the potential of NaNO3–ZnO microcapsules for thermal storage applications. A fast and scalable microencapsulation procedure was developed, a flow calorimetry method was adapted, and a template document created to perform tank thermal transfer simulation by the finite element method (FEM) was set in Microsoft Excel. Differential scanning calorimetry (DSC) and transient plane source (TPS) methods were used to measure, in small samples, the temperature dependency of melting/solidification heat, specific heat, and thermal conductivity of the NaNO3–ZnO microcapsules. Scanning electron microscopy (SEM) and chemical analysis demonstrated the stability of microcapsules over multiple tank charge–discharge cycles. The energy stored as latent heat is available for a temperature interval from 303 to 285 °C, corresponding to onset–offset for NaNO3 solidification. Charge–self-discharge experiments on the pilot tank showed that the amount of thermal energy stored in this interval largely corresponds to the NaNO3 content of the microcapsules; the high temperature energy density of microcapsules is estimated in the range from 145 to 179 MJ/m3. Comparison between real tank experiments and FEM simulations demonstrated that DSC and TPS laboratory measurements on microcapsule thermal properties may reliably be used to design applications for thermal energy storage.

scholarly journals Effects of Ni Additions on the High Temperature Expansion, Melting and Oxidation Behaviors of Cobalt-Based Superalloys

Crystals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 173
Author(s):  
Patrice Berthod ◽  
Lionel Aranda ◽  
Jean-Paul Gomis
Keyword(s):  
Thermal Expansion ◽  
High Temperature ◽  
Mechanical Analysis ◽  
Scanning Calorimetry ◽  
Beneficial Effects ◽  
Ni Addition ◽  
High Temperature Expansion ◽  
High Fraction ◽  
Thermal Analysis Techniques ◽  
Ni Additions

Nickel is often added to cobalt-based superalloys to stabilize their austenitic structure. In this work the effects of Ni on several high temperature properties of a chromium-rich cobalt-based alloy reinforced by high fraction of TaC carbides are investigated. Different thermal analysis techniques are used: differential scanning calorimetry (DSC), thermo-mechanical analysis (TMA) and thermogravimetry (TG). Results show that the progressive addition of nickel did not induce great modifications of microstructure, refractoriness or thermal expansion. However, minor beneficial effects were noted, including reduction of the melting temperature range and slight decrease in thermal expansion coefficient. The most important improvement induced by Ni addition concerns the hot oxidation behavior. In this way, introducing several tens wt % Ni in this type of cobalt-based alloy may be recommended.

scholarly journals Improved high-temperature damping performance of nitrile-butadiene rubber/phenolic resin composites by introducing different hindered amine molecules

e-Polymers ◽  
2020 ◽  
Vol 20 (1) ◽  
pp. 482-490
Author(s):  
Meng Song ◽  
Xiulin Yue ◽  
Xiujuan Wang ◽  
Mengjie Huang ◽  
Mingxing Ma ◽  
...  
Keyword(s):  
High Temperature ◽  
Phenolic Resin ◽  
Thermomechanical Analysis ◽  
Butadiene Rubber ◽  
Scanning Calorimetry ◽  
Nitrile Butadiene Rubber ◽  
Theoretical Support ◽  
Higher Temperature ◽  
Damping Materials ◽  
Hybrid Damping

AbstractBy introducing hindered amine GW-622 or GW-944 into nitrile-butadiene rubber/phenolic resin (NBR/PR, abbreviated as NBPR) matrix, we have prepared different hindered amine/NBR/PR ternary hybrid damping materials with high-temperature damping performance, respectively. Fourier transform infrared (FTIR) spectroscopy, scanning electron microscope (SEM), differential scanning calorimetry (DSC), and dynamic thermomechanical analysis (DMA) were used to research the microstructure, compatibility, and damping properties of the hindered amine/NBPR composites. FTIR results indicate that hydrogen bonds are formed between the hindered amine and the NBPR matrix. Both DSC and SEM results show that hindered amine has partial compatibility with the NBPR matrix. DMA results show that two loss peaks appear in the hindered amine/NBPR composite. Thereby, the composites show better damping performance at a higher temperature, and the temperature domain of high-temperature damping becomes wider with the increase in the addition of hindered amine. This study provides a theoretical support for the preparation of high-temperature damping materials.

EFFECT OF AIR HEATING ON CONCENTRATION OF NITROGEN OXIDES IN COMBUSTION PRODUCTS OF GASEOUS FUELS

2020 ◽  
Vol 0 (10) ◽  
pp. 35-40
Author(s):  
S.I. Gertsyk ◽  
◽  
I.V. Belyakov ◽  
Keyword(s):  
Blast Furnace ◽  
High Temperature ◽  
Nitrogen Oxides ◽  
Combustion Products ◽  
Blast Furnaces ◽  
Natural Gases ◽  
Gaseous Fuels ◽  
Air Heating ◽  
Formation Probability ◽  
Oxide Concentration

The formation probability of nitrogen oxides in combustion products of mixed blast-furnace and natural gases under different conditions of combustion was calculated. It has been found out that heating the air incoming into burners of high-temperature blast-furnaces sharply increases concentration of nitrogen oxides in combustion products (by 1.5-1.75 times). It was notices that in furnaces where temperature was less than 950-1000 °С, heating the air up to 400 °С increased NOx content in gases released to the atmosphere no more than by 20-23%, and oxide concentration was in limits of sanitary standards.

scholarly journals (Ti,Cr)C-Based Cermets with Varied Nicr Binder Content via Elemental SHS for Perspective Cutting Tools

Crystals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 412
Author(s):  
Stepan Vorotilo ◽  
Philipp V. Kiryukhantsev-Korneev ◽  
Boris S. Seplyarskii ◽  
Roman A. Kochetkov ◽  
Nail I. Abzalov ◽  
...  
Keyword(s):  
Solid Solution ◽  
Gas Permeability ◽  
Combustion Velocity ◽  
Cutting Tools ◽  
Secondary Phase ◽  
Fold Increase ◽  
Combustion Products ◽  
Secondary Phase Formation ◽  
Secondary Reactions ◽  
Nickel Binder

The effects of granulation of reactive mixtures Ti-Cr-C and Ti-Cr-C-Ni on the combustion temperature and velocity, as well as phase composition and mechanical properties (crushing ability) of combustion products, were studied. Granulation was associated with a 1.5-fold increase in combustion velocity, caused by a nearly 10-fold increase in gas permeability. Secondary reactions between TiC, Cr7C3, and molten Ni led to the formation of (Ti,Cr)C FCC solid solution and Ni2.88Cr1.12 intermetallics. After the combustion of Ti-Cr-C-Ni mixtures, prolonged fluorescence was registered, suggesting the exothermic nature of secondary phase formation reactions. The introduction of the nickel binder decreased the content of Cr in the solid solution (Ti,Cr)C owing to the formation of the Ni2.88Cr1.12 phase. To prevent the Cr depletion from the carbide solid solution, Ni-20%Cr binder was added to the granulated 80%(Ti + C)/20%(3Cr + 2C) mixture. Combustion of granulated mixture yielded brittle porous sinter cake, which was easy to crush and mill, whereas the combustion products from the powdered mixtures were more ductile and harder to crush.

Inosose-Flüssigkristalle / Inosose Liquid Crystals

1990 ◽  
Vol 45 (7) ◽  
pp. 1084-1090 ◽  
Author(s):  
Klaus Praefcke ◽  
Bernd Kohne ◽  
Andreas Eckert ◽  
Joachim Hempel
Keyword(s):  
Differential Scanning Calorimetry ◽  
Liquid Crystal ◽  
High Temperature ◽  
Liquid Crystalline ◽  
Structural Features ◽  
Lyotropic Liquid Crystal ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Alkyl Chains

Six S,S-dialkyl acetals 2a-f of inosose (1), tripodal in structure, have been synthesized, characterized and investigated by optical microscopy and differential scanning calorimetry (d.s.c.). The four S,S-acetals 2c-f with sufficiently long alkyl chains are thermotropic liquid crystalline; 2 e and 2 f are even dithermomesomorphic. Each of these four inosose derivatives 2c-f exhibits monotropically a most likely cubic mesophase (MI); in addition 2e and 2f show enantiotropically a hexagonal mesophase (Hx) with a non-covalent, supramolecular H-bridge architecture. Whereas the nature of the optically isotropic mesophase MI needs further clarification the stable high temperature mesophase Hx of 2 e and 2 f has been established by a miscibility test using a sugar S,S-dialkyl acetal also tripodal in structure and with a Hx phase proved by X-ray diffraction, but in contrast to 2 with an acyclic hydrophilic part. Similarities of structural features between the Hx-phases of 2e and 2f as well as of other thermotropic and lyotropic liquid crystal systems are discussed briefly.

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