scholarly journals Nitrogen Oxide Evolution in Oxy-Coal Combustion

2019 ◽  
Author(s):  
Sai Krishna Sirumalla ◽  
Aidin Panahi ◽  
Abhir Purohit ◽  
Andrew Baugher ◽  
Yiannis A. Levendis ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Kinetic Model ◽  
Physical Properties ◽  
Hydrogen Cyanide ◽  
Coal Combustion ◽  
Clean Coal ◽  
Nitrogen Gas ◽  
Coal Technology ◽  
Sizable Fraction ◽  
Oxygen Mole Fraction

This paper investigates emissions of NOx from pulverized coal burning in O2/CO2 environments.Such environments are pertinent to oxy-coal combustion, a promising “clean-coal” technology. The replacement of the inert nitrogen gas in air with carbon dioxide, which has different physical properties, alters the combustion conditions in the furnace. Hence, the purpose of thiswork is to theoretically examine the effects of (a) the oxygen concentration in the O2/CO2 gases,and (b) the resulting combustion temperatures, on the evolution of NOx. To achieve these goals apreviously published kinetic model was used, which assumes that fuel-bound nitrogen is releasedalong with the tars during coal devolatilization and converts mostly to hydrogen cyanide. A sizable fraction of hydrogen cyanide is then converted to NO. Flame simulations were performed using Cantera to investigate the relative impacts of temperature and oxygen mole fraction, and to understand the causes of the observed trends.

Review of the Development of Dry Coal Preparation Theory and Equipment

2012 ◽  
Vol 619 ◽  
pp. 239-243 ◽  
Author(s):  
Hai Lin Dong ◽  
Chu Sheng Liu ◽  
Yue Min Zhao ◽  
La La Zhao
Keyword(s):  
Physical Properties ◽  
Coal Preparation ◽  
Clean Coal ◽  
Development Status ◽  
Efficient Separation ◽  
Fine Coal ◽  
Coal Technology ◽  
Research Situation ◽  
Application Prospects ◽  
Screening Equipment

Dry efficient separation of moist fine coal is an important part of the development of clean coal technology. This paper reviewed the research situation of the dry screening theory for moist fine coal and summarized the development status of dry screening equipment. The results show that the moist fine materials have complex physical properties and the theory of dry deep screening needs further improved. Flip-flow screen is a kind of screening equipment with wide application prospects, which can well solve the dry deep screening problem of the moist fine materials.

Influence of intramolecular interactions on carbon dioxide gas adsorption capacity in Mesoporous Imine polymers

2018 ◽  
Author(s):  
Jaya Prakash Madda ◽  
Pilli Govindaiah ◽  
Sushant Kumar Jena ◽  
Sabbhavat Krishna ◽  
Rupak Kishor
Keyword(s):  
Carbon Dioxide ◽  
Adsorption Capacity ◽  
Density Functional ◽  
Gas Adsorption ◽  
Ambient Pressure ◽  
Condensation Reaction ◽  
Intramolecular Interactions ◽  
Carbon Dioxide Adsorption ◽  
Nitrogen Gas ◽  
Adsorption Characteristic

<p>Covalent organic Imine polymers with intrinsic meso-porosity were synthesized by condensation reaction between 4,4-diamino diphenyl methane and (para/meta/ortho)-phthaladehyde. Even though these polymers were synthesized from precursors of bis-bis covalent link mode, the bulk materials were micrometer size particles with intrinsic mesoporous enables nitrogen as well as carbon dioxide adsorption in the void spaces. These polymers were showed stability up to 260<sup>o</sup> centigrade. Nitrogen gas adsorption capacity up to 250 cc/g in the ambient pressure was observed with type III adsorption characteristic nature. Carbon dioxide adsorption experiments reveal the possible terminal amine functional group to carbamate with CO<sub>2</sub> gas molecule to the polymers. One of the imine polymers, COP-3 showed more carbon dioxide sorption capacity and isosteric heat of adsorption (Q<sub>st</sub>) than COP-1 and COP-2 at 273 K even though COP-3 had lower porosity for nitrogen gas than COP-1 and COP-2. We explained the trends in gas adsorption capacities and Qst values as a consequence of the intra molecular interactions confirmed by Density Functional Theory computational experiments on small molecular fragments.</p>

UNIFLUX 70

Alloy Digest ◽  
1978 ◽  
Vol 27 (9) ◽  
Keyword(s):  
Carbon Dioxide ◽  
Fracture Toughness ◽  
Tensile Strength ◽  
Corrosion Resistance ◽  
Carbon Steel ◽  
Physical Properties ◽  
Heat Treating ◽  
Shielding Gas ◽  
Electrode Wire ◽  
Welding Electrode

Abstract UNIFLUX 70 is a continuous flux-cored welding electrode (wire) for welding in carbon dioxide shielding gas in the flat groove and horizontal fillet positions. It is used widely in shipbuilding and other fabricating industries to weld carbon steel and provides around 82,000 psi tensile strength and around 50 foot-pounds Charpy V-notch impact at 0 F. This datasheet provides information on composition, physical properties, elasticity, and tensile properties as well as fracture toughness. It also includes information on corrosion resistance as well as heat treating, machining, and joining. Filing Code: CS-74. Producer or source: Unicore Inc., United Nuclear Corporation.

scholarly journals Generalized Navier–Stokes Equations and Dynamics of Plane Molecular Media

Symmetry ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 288
Author(s):  
Alexei Kushner ◽  
Valentin Lychagin
Keyword(s):  
Carbon Dioxide ◽  
Internal Structure ◽  
Stokes Equation ◽  
Hydrogen Cyanide ◽  
Stokes Equations ◽  
Navier Stokes ◽  
Navier Stokes Equation ◽  
Navier Stokes Equations

The first analysis of media with internal structure were done by the Cosserat brothers. Birkhoff noted that the classical Navier–Stokes equation does not fully describe the motion of water. In this article, we propose an approach to the dynamics of media formed by chiral, planar and rigid molecules and propose some kind of Navier–Stokes equations for their description. Examples of such media are water, ozone, carbon dioxide and hydrogen cyanide.

scholarly journals Micro-kinetic model of electrochemical carbon dioxide reduction over platinum in non-aqueous solvents

2020 ◽  
Vol 22 (16) ◽  
pp. 9040-9045
Author(s):  
Brian A. Rohr ◽  
Aayush R. Singh ◽  
Joseph A. Gauthier ◽  
Michael J. Statt ◽  
Jens K. Nørskov
Keyword(s):  
Carbon Dioxide ◽  
Kinetic Model ◽  
Carbon Dioxide Reduction ◽  
Reduction Reaction ◽  
Proton Donor ◽  
Theoretical Modeling ◽  
Donor Concentration

Theoretical modeling indicates that proton donor concentration and catalyst geometry control the selectivity to multicarbon products in the electrochemical carbon dioxide reduction reaction.

Separation of Methane from Shuttle Tanker Vents Gases by Adsorption on a Polyurethane/Zeolite Membrane

2017 ◽  
Vol 733 ◽  
pp. 42-46
Author(s):  
Habiba Shehu ◽  
Edidiong Okon ◽  
Edward Gobina
Keyword(s):  
Carbon Dioxide ◽  
Physical Properties ◽  
Crude Oil ◽  
Deep Water ◽  
Separation Factor ◽  
Gas Permeation ◽  
Zeolite Membrane ◽  
Alumina Support ◽  
Molar Flux

Shuttle tankers are becoming more widely used in deep water installations as a means of transporting crude oil to storage plants and refineries. The emissions of hydrocarbon vapours arise mainly during loading and offloading operations. Experiments have been carried out on the use of polyurethane/zeolite membrane on an alumina support for the separation of methane from carbon dioxide and oxygen. The physical properties of the membrane were investigated by FTIR. Single gas permeation tests with methane, propane, oxygen and carbon dioxide at a temperature of 293 K and pressure ranging from 0.1 to 1.0 x 10-5 Pa were carried out. The molar flux of the gases through the membrane was in the range of 3 x 10-2 to 1 x 10-1 molm-2s-1. The highest separation factor of CH4/CO2 and CH4/O2 and CH4/C3H8 was determined to be 1.7, 1.7 and 1.6 respectively.

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