Underground gassy longwall mining goafs may suffer potential gas explosions during the process because of irregularity emissions in goaf and poor ventilation working face, which are risks difficult to control. In this work, 3235 face Xutuan Colliery Suzhou City, China, was researched as a case study. The effects air quantity emission on three-dimensional distribution oxygen methane concentration were studied. Based revised Coward's triangle linear coupling region formula, coupled...

In this paper, the thermoelectric conversion characteristics of a device combining TPCT and TGs are studied. The experimental devices consist four parts: heat transfer module, cooling dissipation power generation data collection module. effects different heating powers (100 W, 200 400 600 W) liquid filling rates (10%, 25%, 35%, 45%) on performance research indicates that impact rate is less significant than power. As increases, both will improve finally in relatively stable state. thermal...

The coal fires, a global catastrophe for hundreds of years, have been proved extremely difficult to control, and hit almost every coal-bearing area globally. Meanwhile, underground fires contain tremendous reservoir geothermal energy. Approximately one billion tons burns annually in the world, which could generate ~1000 GW per annum. A game-changing approach, environmentally sound thermal energy extraction from intractable natural coalfield is being developed by utilizing waste reducing...

Coal fires, most of which are triggered by the spontaneous combustion coal, cause a huge waste resources and release poisonous harmful substances into environment, seriously threatening safety industrial production. Gel flame retardant plays core role in coal fire prevention extinguishing. Most gel retardants used fires possess good sealing oxygen isolation properties, but it is difficult for them to flow deep areas due their low fluidity. Some extinguishing agents with fluidity lack...

An experimental investigation on heat extraction using a two-phase closed thermosyphon charged with water (a filling ratio of 40%) for thermoelectric power generation was conducted to study the temperature gradients and conversion characteristics. Results showed that had relatively stable working state at 100–300°C, maximum output increased exponentially difference, being 20 W difference 210°C. The efficiency in Hill function increasing heating input, value approximately 0.01924.

Abstract Heat release of coal combustion in an oxygen-lean and multi-gas environment is a common phenomenon, coalfield fires caused by it can lead to serious environmental destruction loss resources. Simultaneous thermal analysis experiments for Bulianta (BLT, high-volatile bituminous coal) Yuwu (YW, anthracite) 21vol.%O 2 /79vol.%N 15vol.%O /5vol.%CO /80vol.%N were carried out study the law heat release. Based on TG-DTG-DSC curves, characteristic parameters analyzed. Decreasing O...

This study aims at achieving the generation laws of iconic gas compositions produced during process cotton smoldering. A mini tube furnace was used to heat a long-staple sample from Xinjiang, China, and chromatography-mass spectrometer (GC/MS) applied analyze organic inorganic composition different low temperatures ranging 95 °C 185 °C. Besides, thermogravimetric experiment under air atmosphere done in order verify correctness inferences. The pathways product by heating were set forth,...

The present study reports the determining evolution stage of coal combustion bases on its corresponding characteristic behaviours and oxidation kinetics during different stages including newly ignited (NIS), accelerating (AS), consistently burning (CBS), slowly burning-out (SBS), extinct (ES). main combustion, namely, temperature gradients, oxygen consumption, gaseous products, heat release, were investigated using an experimental apparatus. Preliminary criteria for distinguishing a fire...

A contributing student pedagogy in the form of creating multiple-choice questions, answering, rating, and commenting on questions made by other learners is implemented a fourth-year course. An innovative freely available web-based system known as PeerWise used for developing maintaining question repository. Analyzing level engagement with while controlling prior students’ ability showed students lower academic abilities, first quartile, benefited most from this exercise. Those higher levels...

Coalfield fires are a global disaster, causing huge waste of resources and environmental problems. The heat from coalfield have great economic ecological value. efficient transfer performance two-phase closed thermosiphons (TPCTs) the direct power generation thermoelectric generators (TGs) well suited for recovery utilization in fire areas. In this paper, conversion characteristics device combining TPCT TGs studied. effects different heating powers (100W, 200W, 400W, 600W) liquid filling...

Coalfield fires are a global disaster, causing huge waste of resources and environmental problems. The heat from coalfield have great economic ecological value. efficient transfer performance two-phase closed thermosiphons (TPCTs) the direct power generation thermoelectric generators (TGs) well suited for recovery utilization in fire areas. In this paper, conversion characteristics device combining TPCT TGs studied. effects different heating powers (100W, 200W, 400W, 600W) liquid filling...