Physical and Chemical Characteristics of Cenospheres From the Combustion of Heavy Fuel Oil

1989 ◽  
Vol 111 (4) ◽  
pp. 679-684 ◽  
Author(s):  
R. M. Clayton ◽  
L. H. Back

Characterization of an existing sample of cenospheres produced during residual-oil-fired steam power plant combustion included: scanning electron microscopy of surface structure; photomicrography of particle cross sections; measurement of porosity, surface area, and density; and measurement of chemical composition. The studies showed that typical large (100–200 μm) and small (20–40 μm) cenospheres were spheroidal and hollow and had at least one blowhole. The sizes of the blowholes range from 10 to 50 percent of the diameters of the cenospheres. The ratio of outer to inner diameter of the shell was of the order of 1.3–1.4. The shells are porous, the larger ones appearing spongelike, the smaller ones appearing smoother but containing many pores a few micrometers in diameter. The solid portions of the shell appear flaky and layered. A typical cenosphere contained only about 18 percent solid material on a volumetric basis. A relatively concentrated percentage content of elements S, Fe, Na, and V was indicative of the potential contribution to high-temperature corrosion from cenosphere deposition on heat exchanger surfaces.

2010 ◽  
Vol 41 (12) ◽  
pp. 1143-1151 ◽  
Author(s):  
Zhongqing Zheng ◽  
Xiaochen Tang ◽  
Akua Asa-Awuku ◽  
Heejung S. Jung

2008 ◽  
Vol 156 (2) ◽  
pp. 297-305 ◽  
Author(s):  
Rasmus F. Lamberts ◽  
Anders R. Johnsen ◽  
Ole Andersen ◽  
Jan H. Christensen

Fuel ◽  
2018 ◽  
Vol 227 ◽  
pp. 67-78 ◽  
Author(s):  
Vikram Garaniya ◽  
Don McWilliam ◽  
Laurie Goldsworthy ◽  
Mohammadmahdi Ghiji

Fuel ◽  
2019 ◽  
Vol 253 ◽  
pp. 950-963 ◽  
Author(s):  
Abdul Gani Abdul Jameel ◽  
Abdulrahman Khateeb ◽  
Ayman M. Elbaz ◽  
Abdul-Hamid Emwas ◽  
Wen Zhang ◽  
...  

2020 ◽  
Vol 13 (4) ◽  
pp. 1851
Author(s):  
Edmiler José Silva Degrande ◽  
Glauber Verner Firmino ◽  
Marco Aurélio Neri Torres

A necessidade de estudos sobre as questões ambientais, tais como os recursos hídricos, são cada vez mais essenciais como forma de mitigar os impactos adversos promovidos pelas ações antrópicas.  Neste sentido o presente artigo visa analisar a dinâmica fluvial e sua relação com as características limnológicas do córrego do Cedro localizado no município de Presidente Prudente- SP. Para tanto, este estudo avaliou três seções transversais situadas no alto, médio e baixo curso deste ambiente lótico, sendo realizadas coletas em campo de amostras dos principais parâmetros associados a geometria hidráulica do canal como: vazão (Q), largura (w), profundidade (d), e velocidade (v). Para a caracterização limnológica do córrego em questão coletou-se informações sobre o Potencial Hidrogeniônico (pH), com o auxílio de um pHmetro, e a Turbidez (para a qual se utilizou um turbidímetro) e ainda a coleta de sedimentos em suspensão e de leito. A avaliação da carga detrítica em suspensão e de fundo ocorreram no Laboratório de Geologia, Geomorfologia e Recursos Hídricos da Universidade Estadual Paulista (UNESP) campus de Presidente Prudente- SP. Os resultados obtidos demonstram que tanto a dinâmica fluvial quanto as variáveis limnológicas analisadas vêm sofrendo com as formas de uso da terra na bacia repercutindo na entrada de material alóctone de origem tecnogênica, promovendo mudanças no ajuste do sistema fluvial e alterações na característica física e química da água. Dessa forma o estudo tem se mostrado eficaz na correlação entre os dados de geometria hidráulica e limnologia na avaliação ambiental da área em questão.  Fluvial Dynamics and Limnological Characterization of Cedro Stream, President Prudente-SP A B S T R A C TThe need for studies on environmental issues, such as water resources, is increasingly essential as a way of mitigating the adverse impacts caused by human actions. In this sense this article aims to analyze the river dynamics and its relationship with the limnological characteristics of the Cedro stream located in the city of Presidente Prudente-SP. For this, this study evaluated three cross sections located in the high, medium and low course of this lotic environment. Samples were collected in the field of the main parameters associated with the channel hydraulic geometry, such as flow (Q), width (w), depth. (d), and velocity (v). For the limnological characterization of the stream in question we collected information about the Hydrogenionic Potential (pH), with the aid of a pH meter, and the Turbidity (for which a turbidimeter was used), as well as the collection of suspended sediment and bed. The evaluation of the suspended and bottom detrimental load occurred at the Laboratory of Geology, Geomorphology and Water Resources of the Universidade Estadual Paulista (UNESP), Presidente Prudente-SP campus. The results show that both the river dynamics and the limnological variables analyzed have been suffering from land use in the basin, resulting in the entry of allochthonous material of technogenic origin, promoting changes in the fluvial system adjustment and changes in the physical and chemical characteristics of the water. Thus, the study has been shown to be effective in correlating the data of hydraulic geometry and limnology in the environmental assessment of the area in question.Keywords: Hydraulic geometry. Limnology. Environmental diagnosis


2020 ◽  
Vol 5 (2) ◽  
pp. 96
Author(s):  
I Dewe Ketut Anom ◽  
John Z Lombok

Plastic bag waste is garbage that is difficult to degrade in nature. Hoarding plastic bag waste can reduce soil fertility because it cannot be broken down by microorganisms quickly. Burning plastic bag waste can produce toxic gases and have a negative impact on human health and the environment. To solve the problem, the plastic bag waste is converted into liquid smoke as fuel oil. The method used to convert the plastic bag waste into liquid smoke is pyrolysis. The fractionation of liquid smoke at temperatures below 200oC produces 36.20% clear liquid which has similar properties to gasoline fuel. Characterization of the physical and chemical properties of the gasoline fraction liquid smoke has a density of 0.76 g/mL; a viscosity of 0.80 cP; boiling point at 146.9oC; flash point at 30.60oC; a calorific value of 10,520 cal/g; with the octane number of 98 RON. GC-MS analysis shows that the gasoline fraction liquid smoke consists of 45 chemical compounds which can be classified into alkanes, alkenes, cycloalkanes and alcohols.  


Author(s):  
C. Goessens ◽  
D. Schryvers ◽  
J. Van Landuyt ◽  
A. Verbeeck ◽  
R. De Keyzer

Silver halide grains (AgX, X=Cl,Br,I) are commonly recognized as important entities in photographic applications. Depending on the preparation specifications one can grow cubic, octahedral, tabular a.o. morphologies, each with its own physical and chemical characteristics. In the present study crystallographic defects introduced by the mixing of 5-20% iodide in a growing AgBr tabular grain are investigated. X-ray diffractometry reveals the existence of a homogeneous Ag(Br1-xIx) region, expected to be formed around the AgBr kernel. In fig. 1 a two-beam BF image, taken at T≈100 K to diminish radiation damage, of a triangular tabular grain is presented, clearly showing defect contrast fringes along four of the six directions; the remaining two sides show similar contrast under relevant diffraction conditions. The width of the central defect free region corresponds with the pure AgBr kernel grown before the mixing with I. The thickness of a given grain lies between 0.15 and 0.3 μm: as indicated in fig. 2 triangular (resp. hexagonal) grains exhibit an uneven (resp. even) number of twin interfaces (i.e., between + and - twin variants) parallel with the (111) surfaces. The thickness of the grains and the existence of the twin variants was confirmed from CTEM images of perpendicular cuts.


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