Experimental investigation on effects of particle size, dust concentration and dust-dispersion-air pressure on minimum ignition temperature and combustion process of coal dust clouds in a G-G furnace

This article deals with study of minimum ignition temperature (MIT) of thermally modified spruce dust. Dust of several species of spruce was mixed, sieved, dried and subjected to Thermo-S temperature programme. Samples of dust (200 250 μm) were tested in Goldbert-Greenwald furnace apparatus for determination of the MIT of dust clouds. The influence of air pressure and sample weight to the MIT was studied. The results show that the MIT of thermally modified spruce dust gradually decreases as the sample weight and air pressure rise. The lowest value of MIT (470 °C) was measured, when the air pressure was 50 kPa and the sample weight 0,5 g. To reach even lower values of MIT (˂468 °C), the air pressure should gradually rise to approx. 42 46 kPa and the weight of dust sample should be approx. 0,46 0,53 g.

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Experimental study on the minimum ignition temperature of coal dust clouds in oxy-fuel combustion atmospheres

Journal of Hazardous Materials ◽

10.1016/j.jhazmat.2015.12.051 ◽

2016 ◽

Vol 307 ◽

pp. 274-280 ◽

Cited By ~ 24

Author(s):

Dejian Wu ◽

Frederik Norman ◽

Filip Verplaetsen ◽

Eric Van den Bulck

Keyword(s):

Experimental Study ◽

Ignition Temperature ◽

Coal Dust ◽

Fuel Combustion ◽

Dust Clouds ◽

Minimum Ignition Temperature

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Experimental Study on Combustion Characteristics of Biomass and Coal Blended

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.805-806.200 ◽

2013 ◽

Vol 805-806 ◽

pp. 200-207

Author(s):

Bing Zhang ◽

Guang Wu Lu

Keyword(s):

Particle Size ◽

Ignition Temperature ◽

Combustion Process ◽

Combustion Characteristics ◽

Combustion Characteristic ◽

Thermogravimetric Analyzer ◽

Rate Of Combustion ◽

Mixing Proportion ◽

Biomass Particle Size ◽

Obvious Weight Loss

Under different conditions,combustion characteristics of the single biomass,the single coal and the mixture of biomass and coal were analyzed by using thermogravimetric analyzer. Combustion characteristic parameters of the sawdust,the rice husk,the rice straw and the Baisha coal of Leiyang were studied,including ignition temperature,the maximum rate of combustion temperature,the burnout temperature and so on. The experimental results show that the biomass burning temperature is lower than the Baisha coal and there are two obvious weight loss phases in the combustion process of the biomass. However,there is only one in the coal. The ignition temperature and time of the coal can be reduced ,the temperature range of the entire combustion can be extended,the coal can be burnout more well and the fuel combustion characteristic can be optimized by blending combustion. With the increase of biomass mixing proportion, the ignition temperature of mixing samples was decreased more obviously. Moreover,when the biomass particle size becomes R200,compared with R90 particle size under the same blending ratio,its ignition temperature is more lower.

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Variation of ignition sensitivity characteristics of non-stick coal dust explosions

International Journal of Low-Carbon Technologies ◽

10.1093/ijlct/ctaa046 ◽

2020 ◽

Author(s):

Di Sha ◽

Yucheng Li ◽

Xihua Zhou ◽

Ruiqing Li

Keyword(s):

Ignition Temperature ◽

Coal Dust ◽

Dust Cloud ◽

Particle Sizes ◽

Ignition Energy ◽

Minimum Ignition Energy ◽

Dust Layer ◽

Independent Variables ◽

Minimum Ignition Temperature ◽

Dust Explosions

Abstract The ignition and explosion of coal dust are significant hazards in coal mines. In this study, the minimum ignition temperature and energy of non-stick coal dust were investigated empirically at different working conditions to identify the key factors that influence the sensitivity and characteristics of coal dust explosions. The results showed that for a given particle size, the minimum ignition temperature of the coal dust layer was inversely related to the thickness of the coal dust layer. Meanwhile, when the layer thickness was kept constant, the minimum ignition temperature of the coal dust layer decreased with smaller coal dust particle sizes. Over the range of particle sizes tested (25–75 μm), the minimum ignition temperature of the coal dust cloud gradually increased when larger particles was used. At the same particle size, the minimum ignition temperature of the coal dust layer was much lower than that of the coal dust cloud. Furthermore, the curves of minimum ignition energy all exhibited a minimum value in response to changes to single independent variables of mass concentration, ignition delay time and powder injection pressure. The interactions of these three independent variables were also examined, and the experimental results were fitted to establish a mathematical model of the minimum ignition energy of coal dust. Empirical verification demonstrated the accuracy and practicability of the model. The results of this research can provide an experimental and theoretical basis for preventing dust explosions in coal mines to enhance the safety of production.

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