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Abstract

Cotton is a flammable material and some cottons would decompose or even self-ignite at bad storage and transport conditions. This paper studied the spontaneous combustion of cotton from the aspect of thermal decomposition temperature (TDT) and critical ambient temperature (CAT). From Fourier transform infrared spectroscopy analysis and chromatographic and mass spectrometric analysis, significant thermal decomposition was detected at the temperature of 210\,^\circ \hbox {C}, which indicated that the TDT of cotton was around 210\,^\circ \hbox {C}. From TG analysis and small-scale CAT test, activation energy of cotton and CAT of small cotton stack were obtained. Then, CATs of the cotton stacks with different dimensions were calculated based on Frank-Kamenetskii theory. With the dimensions l increased from 0.2 to 3.2 m, the CATs of cotton decreased from 195.0 to 137.9\,^\circ \hbox {C}. The TDT of cotton was higher than these CATs, and the differences between TDT and CAT of cotton varied from almost 15–70\,^\circ \hbox {C} (with the dimensions l increased from 0.2 to 3.2 m). As the experiments and calculation of the CATs were very complicated and time-consuming, the CATs of cotton can be estimated if the TDT was known. The result of this paper was especially meaningful for evaluating the risk of spontaneous combustion of cotton and speculating the reason of cotton fire.

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... We came to the conclusion, after a detailed literature survey, that only limited experimental methods have been developed to check the self-heating and spontaneous ignition of agricultural products, e.g., coal, wheat, and hay [5,[16][17][18][19][20][21], including basket heating, the crossing-point temperature method proposed by Worden (2011), thermogravimetric analysis (TGA) conducted by Khattab (1999), the Ordway apparatus used by Thompson (1928), and the Mackey apparatus method proposed by Khattab et al. (1999) [22]. Also, some researchers proposed solutions to measure and control external weather conditions of the storage area only, and they aim to improve safety mechanisms there [16,20,21]; one study focused on chemical processes to identify gases produced during smoldering [17], and little work has been done to investigate factors contributing to SC and its effect on cotton quality [5,19]. ...
... We came to the conclusion, after a detailed literature survey, that only limited experimental methods have been developed to check the self-heating and spontaneous ignition of agricultural products, e.g., coal, wheat, and hay [5,[16][17][18][19][20][21], including basket heating, the crossing-point temperature method proposed by Worden (2011), thermogravimetric analysis (TGA) conducted by Khattab (1999), the Ordway apparatus used by Thompson (1928), and the Mackey apparatus method proposed by Khattab et al. (1999) [22]. Also, some researchers proposed solutions to measure and control external weather conditions of the storage area only, and they aim to improve safety mechanisms there [16,20,21]; one study focused on chemical processes to identify gases produced during smoldering [17], and little work has been done to investigate factors contributing to SC and its effect on cotton quality [5,19]. There is a big research gap in the detection and prevention of cotton 1. ...
... The thermal decomposition temperature (TDT) and critical ambient temperature (CAT) of cotton were found (Luo, Q., et al. 2017) [19]. They stated in their article that good storage conditions are very crucial for cotton, as it is a highly flammable substance, and with bad storage it can decompose, catch fire as a result of external factors, and it can even self-ignite. ...
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Revised and significantly expanded, the fifth edition of this classic work offers both new and substantially updated information. As the definitive reference on fire protection engineering, this book provides thorough treatment of the current best practices in fire protection engineering and performance-based fire safety. Over 130 eminent fire engineers andresearchers contributed chapters to the book, representing universities and professional organizations around the world. It remains the indispensible source for reliable coverage of fire safety engineering fundamentals, fire dynamics, hazard calculations, fire risk analysis, modeling and more. With seventeen new chapters and over 1,800 figures, the this new editioncontains: • Step-by-step equations that explain engineering calculations • Comprehensive revision of the coverage of human behavior in fire, including several new chapters on egress system design, occupant evacuation scenarios, combustion toxicity and data for human behavior analysis • Revised fundamental chapters for a stronger sense of context • Added chapters on fire protection system selection and design, including selection of fire safety systems, system activation and controls and CO2 extinguishing systems • Recent advances in fire resistance design • Addition of new chapters on industrial fire protection, including vapor clouds, effects of thermal radiation on people, BLEVEs, dust explosions and gas and vapor explosions • New chapters on fire load density, curtain walls, wildland fires and vehicle tunnels • Essential reference appendices on conversion factors, thermophysical property data, fuel properties and combustion data, configuration factors and piping properties.
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The term will be used here to refer to the general phenomenon of an unstable (usually oxidizable) material reacting and evolving heat, which to a considerable extent is retained inside the material itself by virtue of poor thermal conductivity of either the material or its container. Under some circumstances this process can lead to flaming combustion and overt fire, in which case it is properly called spontaneous ignition, which here is regarded as a special case of spontaneous combustion. This has been responsible for significant losses of life and enormous losses of property. Fire loss statistics from many sources show that spontaneous ignition is quoted as the cause in a much greater proportion of cases with multimillion-dollar losses than in smaller fires. Of course, one should also note that the proportion of “cause unknown” results follows a similar trend, probably due to the greater degree of destruction, and hence evidence loss, in larger fires © Society of Fire Protection Engineers 2016. All rights reserved
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Many cotton fires were caused by spontaneous combustion, to identify the possible cause of such fires, a C80 microcalorimeter was employed in this paper. The cotton samples, dry or wetted, were sealed and heated from ambient temperature to 300°C at a 0.2°Cmin−1 heating rate. The result indicated that the dry cotton may not be the self-heating materials, but once it is wetted, its thermal stability is decreased with lower onset temperature and with larger heat generation, which can result to spontaneous combustion. It is speculated that microbiological degradation of cotton fibers has the potential to evolve methane and/or oxygen that in vapor phase could lead to spontaneous combustion. And therefore, it is confirmed that C80 can be used as an effective instrument to identify the cause of cotton spontaneous combustion fire.
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A new method of obtaining the kinetic parameters from thermogravimetric curves has been proposed. The method is simple and applicable to reactions which can not be analyzed by other methods. The effect of the heating rate on thermogravimetric curves has been elucidated, and the master curve of the experimental curves at different heating rates has been derived. The applications of the method to the pyrolyses of calcium oxalate and nylon 6 have been shown ; the results are in good agreement with the reported values. The applicability of the method to other types of thermal analyses has been discussed, and the method of the conversion of the data to other conditions of temperature change has been suggested. From these discussions, the definition of the thermal stability of materials has been criticized.
Article
The application of polymers at ever-increasing temperatures has given impetus to research on the chemistry of thermal decomposition. In recent years polymers have been used for a variety of high-temperature applications, such as cooking vessels, motor insulation, and re-entry vehicle heat shields. Interest in chemistry of decomposition has been found in such industries as tobacco and grinding-wheels. Because of the vast number of polymers that are available and the variety of applications thousands of papers have appeared in the literature. Rather than give a complete review the purpose of this paper is to give a brief survey of topics that have been emphasized in the author's research, namely kinetics, mechanisms, and gaseous decomposition products at elevated temperatures.
Article
A technique was devised for obtaining rate laws and kinetic parameters which describe the thermal degradation of plastics from TGA data. The method is based on the inter-comparison of experiments which were performed at different linear rates of heating. By this method it is possible to determine the activation energy of certain professes without knowing the form of the kinetic equation. This technique was applied to fiberglass-reinforced CTL 91-LD phenolic resin, where the rate law - (1/we)(dw/dt) = 1018e−55,000/RT [(w - wf)/w0,]5, nr.−1, was found to apply to a major part of the degradation. The equation was successfully tested by several techniques, including a comparison with constant temperature data that were available in the literature. The activation energy was thought to be correct within 10 kcal.
Article
The present recommendations have been developed by the Kinetics Committee of the International Confederation for Thermal Analysis and Calorimetry (ICTAC). The recommendations offer guidance for reliable evaluation of kinetic parameters (the activation energy, the pre-exponential factor, and the reaction model) from the data obtained by means of thermal analysis methods such as thermogravimetry (TGA), differential scanning calorimetry (DSC), and differential thermal analysis (DTA). The recommendations cover the most common kinetic methods, model-free (isoconversional) as well as model-fitting. The focus is on the problems faced by various kinetic methods and on the ways how these problems can be resolved. Recommendations on making reliable kinetic predictions are also provided. The objective of these recommendations is to help a non-expert with efficiently performing analysis and interpreting its results.Highlights► Kinetics concepts are introduced and advices on collecting data are given. ► Methods based on multiple temperature programs are recommended. ► Evaluation of log A and f(α) or g(α) for isoconversional methods is described. ► Principles of securing reliability of model-fitting computations are offered. ► Problems of kinetic predictions and approaches to solving them are discussed.
Article
The thermal degradation of samples of used cotton fabrics has been investigated using thermogravimetric analysis (TGA) between room temperature and 700 °C. Experiments were carried out with about 5 mg of sample in three different atmospheres: helium, 20% oxygen in helium and 10% oxygen in helium. Three different heating rates were used at each atmosphere condition. A kinetic model for the decomposition of used cotton fabrics explaining the behavior of all the runs performed has been proposed and tested. For the pyrolysis of the cotton, the model comprises two parallel reactions. For the combustion process, one competitive reaction was added to each parallel reaction of the pyrolysis model and four combustion reactions of the different solid fractions to obtain volatiles. One single set of parameters can explain all the experiments (pyrolysis, oxidative pyrolysis and combustion) at the three different heating rates used.
Article
Dynamic TG analysis under nitrogen was used to investigate the thermal decomposition processes of 10 types of natural fibers commonly used in the polymer composite industry. These fibers included wood, bamboo, agricultural residue, and bast fibers. Various degradation models including the Kissinger, Friedman, Flynn–Wall–Ozawa, and modified Coats–Redfern methods were used to determine the apparent activation energy of these fibers. For most natural fibers approximately 60% of the thermal decomposition occurred within a temperature range between 215 and 310 °C. The result also showed that an apparent activation energy of 160–170 kJ/mol was obtained for most of the selected fibers throughout the polymer processing temperature range. These activation energy values allow developing a simplified approach to understand the thermal decomposition behavior of natural fibers as a function of polymer composite processing.
Article
Study of thermal decompositions of cotton and flame-retardant cotton fabrics can assist understanding of fire-resistant functions of the materials. In this research, differential scanning calorimeter (DSC), thermogravimetric analysis (TGA) and pyrolysis–gas chromatography–mass spectroscopy (PY–GC–MS) were employed to investigate decomposition processes and decomposed products of flame-retardant treated (using an organo-phosphorus compound) and untreated cotton fibers in the pyrolysis. The thermal decomposition temperatures, weight losses and potential reactions of the pyrolysis as well as resulted fragments, were analyzed. The results are helpful in understanding of mechanisms of flame-retardant cotton fabrics.
SFPE handbook of fibre protection engineering
  • B Gray
  • M J Hurley
Gray B. Spontaneous combustion and self-heating. In: Hurley MJ, et al., editors. SFPE handbook of fibre protection engineering. 5th ed. New York: Springer; 2016. p. 604-32. doi:10.1007/ 978-1-4939-2565-0.