Early prediction is one of the key technologies to prevention and extinguishment spontaneous combustion coal. The aim this study was propose a type scientific convenient forecasting indicator for initial coal in gob area. authors developed calculation model carbon monoxide (CO) concentration air return corner based on generation mechanism, sources, influencing factors CO. parameters obtained from both large-scale self-heating experiment in-situ observation four collieries Yuanyang lake mine...

Relative to conventional coal pillar retention mining technology (the 121 method), gob-side entry retaining by cutting roof 110 a non-pillar technique, efficiently addresses issues like poor resource recovery and significant rock burst damage. Nonetheless, the open-type goaf created techniques suffers from complex air leaks, increasing likelihood of spontaneous combustion (CSC) within gob area. To address CSC problem caused leakage cutting, this study takes 17202 working face Dongrong Second...

With the rapid development of urbanization, fire risk factors have increased greatly, indicating a higher requirement for urban firefighting security. Fire rescue capabilities can be effectively improved by scientific layout stations, and therefore, optimal spatial arrangement stations has practical implications safety. In this paper, method planning locations is presented, taking into account points interest (POIs) data, road networks station principles. The combined model validated against...

Spontaneous combustion of residual coal in a gob due to air leakage poses major risk mining safety. Building an airtight wall is effective measure for controlling leakage. A new type inorganic solidified foam-filled material was developed and its physical chemical properties were analyzed experimentally. The compressive strength this increased with the amount sulphoaluminate cement. With increasing water–cement ratio, initial setting time gradually extended while final firstly shortened then...

A good understanding of the evolution CO concentration in return corner is great value for predicting and controlling spontaneous combustion coal. This study investigated characteristics distribution a gob with steady U-type ventilation working face relationship between intensity coal oxidation reaction area. Coal generated by was modeled using COMSOL Multiphysics simulation software. The results showed that exhibits "peaks" on horizontal section highest middle gob. With thermal accumulation...

Coal resources are rich in China. They mainly concentrated the northwest region. But these also make situation of spontaneous coal combustion hazards most serious this area. Affected by arid and semiarid climate, water resource area is relatively scarce. In order to improve utilization rate water, a macromolecule colloid for mine fire fighting was developed research. The main components principle gel formation were analyzed. physical chemical properties analyzed time gelation loss. content...

To investigate the actual gas explosion and propagation laws in roadway of an underground mine, experiments were conducted a standard 19-L tube rectangular section to provide comprehensive understanding effects carbon monoxide (CO) addition obstacles placed on flame explosions from methane–air mixtures at different conditions. The structure, speed, heat loss, pressure used reflect behaviors premixed flame. experimental results indicate that enhancement attenuation wave are significantly...

Owing to the low coal permeability coefficients and poor gas extraction efficiencies associated with of in Huainan mining area, aim this study was design, for first time, a high-pressure low-temperature liquid CO2 (LCO2) pump engineering tests respect fracturing seams improvement CH4 recovery China. To reasonably calculate initiation pressure seam as well flow parameters, theoretical analysis field testing were integrated design. In addition, considering interim standard, equivalent radius...

Timber is the most widely used material for furniture in view of its characteristics light mass, high strength, easy processing, coloring, and decorative appearance. However, flammability wood has been frequently associated with increased fire intensity rapid spread buildings. In this paper, combustion performance six kinds common timber was investigated based on thermogravimetric analysis at 25–500 °C, cone calorimetry 50 kW/m2 thermal radiation intensity, flame experiments 3 intensity. The...

Arc beads are high-temperature luminous electric discharges that form across a gap between two bodies, which is one of the vital forensic pieces evidence for evaluation electrical fires. In this study, based on an actual fire, microstructure arc from copper wire experienced overcurrent fault was investigated by optical microscopy and scanning electron microscopy. Moreover, effects intensity grain morphology, trace elements, were analyzed. The results showed simulated metallographic structure...

Abstract Using liquid carbon dioxide (LCO 2 ) as a medium for underground coal fires prevention and control, while reducing the emissions of CO , is promising option utilization worldwide. However, mechanism LCO flow with phase transition on temperature still not clear. In this work, an experimental system was designed fabricated to investigate behavior variation during injecting into pulverized impact mass rate, nozzle diameter, injection pressure cooling effect. The results indicate that...

To clarify the understanding and analysis of arc molten marks in electrical faults aluminum alloy wires, this paper simulates overcurrent wires at currents 128 A–224 A uses thermogravimetry-differential scanning calorimetry (TG-DSC), optical microscope (OM), electron (SEM) X-ray energy spectroscopy (EDS) to characterize effects current on microstructure beads. The results show that there are small large amounts Al-Si Al-Fe binary phases metallographic structure rated current, grains fine, no...

The safety issues are a major restriction on coal mining and growing efforts being made in the search for solutions that will guarantee sustainable use of energy resources. Liquid carbon dioxide is attracting particular interest fire-fighting due to promising efficiency cooling asphyxia. Our objective develop valid model simulate dispersion thermal behaviors liquid under crushed condition assessment injection fire-fighting. For this purpose, numerical approach which requires an accurate...

The fire of coal pillars caused by spontaneous combustion in contiguous seams at the Dongrong2# colliery China was examined. reasons 16# seam were investigated. Based on testing results, scope high temperature judged. To deal with problem significant air leakage together a large area and hidden source easily re-ignite, series key techniques for extinguishing put into practice. These mainly included plugging channel, high-flow injection liquid nitrogen, infusion quantity foam inhibitor flame...