scholarly journals A study on spontaneous ignition of bituminous coal

2009 ◽  
Vol 13 (1) ◽  
pp. 105-112 ◽  
Author(s):  
Xin-Rui Li ◽  
Hiroshi Koseki ◽  
Yusaku Iwata
Keyword(s):  
Carbon Dioxide ◽  
Thermal Analysis ◽  
Heat Flux ◽  
Bituminous Coal ◽  
Activity Monitor ◽  
The Self ◽  
Spontaneous Ignition ◽  
Thermal Activity ◽  
Self Heating ◽  
Temperature Programmed

The thermal properties of four bituminous coals were studied using isothermal and temperature-programmed calorimeters, such as a differential thermal analysis, a heat flux calorimeter C80 and an thermal activity monitor (TAM-III). The corresponding spontaneous ignition was measured in an adiabatic spontaneous ignition tester. It was found that there were weak exothermic activities in bituminous coal at 50-100?C and meanwhile carbon monoxide and carbon dioxide was generated. These thermal behaviors are responsible for the self heating from 50?C and spontaneous ignition at 80?C.

Kinetics of temperature-programmed reactivation of a hydrodesulphurization catalyst

1983 ◽  
Vol 48 (12) ◽  
pp. 3340-3355 ◽  
Author(s):  
Pavel Fott ◽  
Pavel Šebesta
Keyword(s):  
Carbon Dioxide ◽  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Thin Layer ◽  
Kinetic Parameters ◽  
Diffusion Region ◽  
Reaction Heat ◽  
Gaseous Products ◽  
Temperature Programmed ◽  
Kinetics Of

The kinetic parameters of reactivation of a carbonized hydrodesulphurization (HDS) catalyst by air were evaluated from combined thermogravimetric (TG) and differential thermal analysis (DTA) data. In addition, the gaseous products leaving a temperature-programmed reactor with a thin layer of catalyst were analyzed chromatographically. Two exothermic processes were found to take part in the reactivation, and their kinetics were described by 1st order equations. In the first process (180-400 °C), sulphur in Co and Mo sulphides is oxidized to sulphur dioxide; in the second process (300-540 °C), in which the essential portion of heat is produced, the deposited carbon is oxidized to give predominantly carbon dioxide. If the reaction heat is not removed efficiently enough, ignition of the catalyst takes place, which is associated with a transition to the diffusion region. The application of the obtained kinetic parameters to modelling a temperature-programmed reactivation is illustrated on the case of a single particle.

Steady Behaviour of Long Duration in the Spontaneous Heating of a Bituminous Coal

1996 ◽  
Vol 14 (2) ◽  
pp. 159-166 ◽  
Author(s):  
J.C. Jones
Keyword(s):  
Steady State ◽  
Bituminous Coal ◽  
The Self ◽  
Temperature History ◽  
Spontaneous Heating ◽  
Self Heating ◽  
Long Duration ◽  
Solid Substrates ◽  
State Behaviour ◽  
Steady State Behaviour

So-called steady state behaviour in laboratory scale self-heating of solid substrates such as carbons and cellulosics has rarely if ever been truly steady, but has displayed a maximum in the temperature history. This is due to volatiles and/or to porosity. In this paper it is argued that the self-heating of a bituminous coal will, at the temperatures concerned, be free from these ef fects and will therefore display genuinely steady behaviour. This assertion is tested by experimental work on a Scottish bituminous coal, in which sustained steady behaviour is indeed observed, with a heat release rate calculated to be ~ 3 kW m -3.

A study of the self-heating of fresh and oxidized coals by differential thermal analysis

1996 ◽  
Vol 279 ◽  
pp. 93-101 ◽  
Author(s):  
JoséJ. Pis ◽  
G. de la Puente ◽  
E. Fuente ◽  
A. Morán ◽  
F. Rubiera
Keyword(s):  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
The Self ◽  
Self Heating

scholarly journals Analysis of the effects of storage conditions on the preservation of soybean quality and the prevention of the self-heating process and the occurrence of fires

2012 ◽  
Vol 66 (4) ◽  
pp. 587-594
Author(s):  
Verica Milanko ◽  
Dusan Gavanski ◽  
Mirjana Laban
Keyword(s):  
Carbon Dioxide ◽  
Moisture Content ◽  
Raw Materials ◽  
Storage Conditions ◽  
The Self ◽  
Inert Gases ◽  
Self Heating ◽  
Carbon Dioxide Atmosphere ◽  
Domestic Practice

After harvest, oilseed raw materials must be stored for a longer or shorter period of time before further processing. The task of storage is the safekeeping of the stored material with a minimal loss in quality. In order to preserve wet grain until processing, it is necessary to provide proper storage conditions. For this purpose, storage in the atmosphere of inert gases as well as storage in hermetically closed storages is applied. Such method is uncommon for oil cultures in domestic practice. Experimental research, analyzed in this paper, with emphasis on the effects of storage conditions on the preservation of soybean grain quality and the prevention of possibilities of the occurrence of the self-heating and self-ignition process, confirms the advantages of application of such method of storage for soybean grain. Soybean with the moisture content of 10.99% and 16.96% is stored in steel semi-industrial silo cells with carbon-dioxide atmosphere, and in hermetically sealed cell. The changes in temperature in the silo cells, changes in moisture content and discoloration of the soybean grains, as well as the amount of oil and protein in the grain were monitored during the experiment. The quality of the oil in grain was determined through the content of free fatty acids. The results of the research showed that, during longer period of time (216 days), the quality of the soybean grain in the sample with higher moisture content (16,96%) was preserved when storage was performed in carbon dioxide atmosphere. The storage of wet grain in a hermetically closed cell, in relation to the grain kept in carbon dioxide atmosphere, did not record significant differences in the examined indicators. Since the storage under controlled conditions did not result in the development of processes that would lead to the spontaneous heating of the soybean mass, the recommendation is to introduce such storage method for oilseed raw materials into domestic practice, with the additional aim of increasing the degree of protection against fire and explosions.

Investigation of the self-heating and spontaneous ignition of refuse-derived fuel (RDF) during storage

2010 ◽  
Vol 30 (7) ◽  
pp. 1161-1164 ◽  
Author(s):  
Akio Yasuhara ◽  
Yuko Amano ◽  
Takayuki Shibamoto
Keyword(s):  
The Self ◽  
Spontaneous Ignition ◽  
Self Heating ◽  
Refuse Derived Fuel

scholarly journals Heat production in municipal and industrial waste as revealed by isothermal microcalorimetry

2021 ◽  
Author(s):  
Mohit Pushp ◽  
Anders Lönnermark ◽  
Mikael Hedenqvist ◽  
Peter Vikegard
Keyword(s):  
Carbon Dioxide ◽  
Gas Chromatography ◽  
Heat Production ◽  
Industrial Waste ◽  
Gas Analysis ◽  
The Self ◽  
Self Heating ◽  
Different Temperatures ◽  
Geographical Locations ◽  
Smouldering Combustion

AbstractSelf-ignited fires at municipal solid waste (MSW) storage sites are relatively common. The minimization of the phenomenon of self-heating in the waste can reduce the risks for smouldering combustion. The purpose of this work was to develop a method that can be used to measure and characterize the heat production in MSW. The method is based on isothermal heat conduction microcalorimetry (IMC). The heat production in MSW was determined based on sampling from two sites in two different geographical locations in Sweden. Both the original waste and milled/homogenised waste were tested. The heat production was measured at different temperatures together with gas analysis using micro-gas chromatography. The activity in the waste, in terms of its heat flow, increased when the temperature increased up to 60 °C and decreased at higher temperatures, e.g., 70 and 80 °C. The consumption of oxygen and the production of carbon dioxide, together with the heat production, indicated that aerobic metabolism was responsible for the heat production. This is further strengthened by the marginal heat production observed for ultraviolet treated waste. The results showed that IMC is a valuable tool for characterising the self-heating in municipal and industrial waste.

scholarly journals Effect of wood biomass components on self-heating

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Nozomi Miyawaki ◽  
Takashi Fukushima ◽  
Takafumi Mizuno ◽  
Miyao Inoue ◽  
Kenji Takisawa
Keyword(s):  
Moisture Content ◽  
Inductively Coupled Plasma ◽  
Optical Emission ◽  
Chemical Oxidation ◽  
Spontaneous Ignition ◽  
Emission Spectrometry ◽  
Inductively Coupled ◽  
Self Heating ◽  
Inorganic Substances ◽  
Before And After

AbstractBiomass may ignite due to biological oxidation and chemical oxidation. If this phenomenon (spontaneous ignition) is controlled, it would be possible to produce biochar at a lower cost without the need for an external heat resource. We investigated if self-heating could be controlled by using sawdust and bark chips. When sawdust and bark chips were used under controlled conditions, the bark chips temperature increased to the torrefaction temperature. The ash content of bark chips was ~ 2%d.b. higher than that of sawdust; consequently, the inorganic substances contained in the bark chips might affect the self-heating. Self-heating was suppressed when inorganic substances were removed by washing with water. Therefore, the inorganic substances in the biomass might have affected self-heating. The inorganic element contents of the bark chips were measured by inductively coupled plasma optical emission spectrometry before and after washing. The potassium content of the bark chips was reduced remarkably by washing, and there was a possible influence of potassium on self-heating. Finally, the effect of moisture content on self-heating was investigated to obtain stable reactivity. Thus, at a moisture content of 40%w.b., a steady self-heating behavior may be realized.

Numerical modelling of the self-heating process of a wet porous medium

2011 ◽  
Vol 54 (25-26) ◽  
pp. 5200-5206 ◽  
Author(s):  
A. Ejlali ◽  
D.J. Mee ◽  
K. Hooman ◽  
B.B. Beamish
Keyword(s):  
Porous Medium ◽  
Numerical Modelling ◽  
The Self ◽  
Heating Process ◽  
Self Heating
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