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According to the analysis of coal mine gas explosion accidents in recent years,the main reason is that the main ventilator was unplanned outage, power supply failed to recover in time, resulting in the accumulation of gas is over the limit, eventually lead to gas explosion, which have an important influence on the safety operation of coal mine.It has been proved that, the power supply rapid switching device developed for mine, can significantly improve the reliability of power supply system, ensure the continuous operation of the ventilators, reach to the purpose of intrinsic safety in coal mine in a certain extent.

Based on the poor light, poor ventilation, limited roadway condition, high humidity and other special coal mine working environment, taking the trackless auxiliary haulage vehicles droved by the explosion proof diesel engine as the research object, the several factors affecting vehicles comfort are elaborated from four technology aspects such as the vehicle arrangement, harshness, driving operating and driving environment, and intelligent automation in detail. Some new corresponding design ideas and practical measures are put forward. It offers the beneficial exploration for improving the mining vehicles comfort.

Based on the ultra-high mining roadway about 5.2×7.5m in thick coal seam appeared in SONG Jia-gou coal min. Distribution characteristic between height 3.5-7.5m is simulated in surrounding rock mass plastic zone: the plastic zone distributes in a half-circle in roof, floor and two sides. The area and depth of the plastic zone in two sides increase obviously with the increasing of roadway height. The roadside relative convergence,roof convergence,floor heave is proportional to the roadway height. Based on the distribution of the plastic zone and the current support method, timely support technology with high-strength and high-pre-tightening force and reinforced support technology with diagonal cable are put forward. The support parameters are determined based on engineering analogy method and theoretical analysis. The case proves that the total convergence of relative side- side and roof-floor relative are 150mm and 104mm respectively and provides references for similar conditions.

Abstract：In view of the severe floor failures of large cross-sectional mining roadway in No.1 Coal Mine of China Coal Pingshuo Group Co., ltd, this article analyzed the conditions of surrounding rock, studied the mechanism of the floor heave in large cross-sectional mining roadway of fully mechanized top coal caving. The combinatorial controlling measures which called “pressure-relief and reinforced supporting” were put forward; these were the specific implementation of excavating pressure-relief cutting and optimization roadway-side supporting. Additionally，through field test of roadway floor damage depth, the digging depth of pressure-relief cutting was determined as 0.6 ~ 0.8 m. Through the engineering tests of the combinatorial controlling technique，the results showed that the maximum displacement and the maximum rate of floor heave were 227 mm and 38.5 mm/d．Thus，the combinatorial controlling technique can effectively control the floor heave and keep the surrounding rock in stable.

In the use of the heading machine through fault upgoing high-angle roadway construction, especially track slip and unstability of the machine through fault, by increasing the heading machine crawler with bottom friction, cutting head power, optimizing the cutting line and using the way of caterpillar's rotation traction runway, we cccelerate the driving speed, simplify working processes and reduce the labor intensity, and then implement the heading machine in the successful application of the high-angle bord-up construction. Break through the slope limit of high-angle roadway upgoing construction, for the heading machine through fault high-angle roadway construction accumulated the experience.

The article is based on the technical conditions of 39107 caving face and particle composition analysis result in Pingshuo Coal Industry Company No.3 Coal Mine, determine the use of Malisan grouting reinforcement to wind oxidation zone; through comparative experimental results both traditional grouting technology and intermittent grouting technology, intermittent grouting technology may artificially control grouting seepage radius and apt to form network skeleton; and carry on advance pregrouting reinforcement to wind oxidation zone, by drilling peep france detecting and showing that reinforcement effect and penetration effect of intermittent grouting technology is better, saving grouting materials cost is 56%. So Intermittent Grouting has extensive Application prospects.

Abstract: Da-tong Mine material roadway encountered difficulties of rock stress concentration, poor stability , roadway construction and security threats ,because through goaf roadway (In other wordsroadside is only small mine destroyed zone). Through theoretical analysis, field sampling laboratory parameters measured, program design, expert consultation, presented a support using anchor net shotcrete method using secondary support miners, steel reinforced concrete sidewall + Roof Beam secondary support on the roof separation monitoring results show that the anchoring methods and parameters can effectively control anchoring rock deformation. during excavation

The safety assessment is not only an important instrument for an enterprise to realize safe production,but also provides decision-making basis for government safe production supervision and management. Working quality of safety assessment organization directly affects the safety assessment quality. The paper analyzed the main factors influenced to working quality of safety assessment organization from the enterprise, government safe production supervision and management departments and safety assessment organization, and put forward some countermeasures and suggestions. Due to the practices of the related measures，working quality of safety assessment organization can be improved.

There is a series of features of the strata-pressure behavior of hard surrounding rock which is affected by dynamic pressure, such as the caving of the roof is difficult, sudden and large-area. In this paper we focus on the mining and support of 14-1103 working face, In view of the problems of the mine such as the roof is hard to caving, the suspension-area is huge and the safe of the working face is under a great threat, theoretical analysis and field monitoring is used in the study of the strata-pressure behavior. The study indicates that the influence of the advance on the surrounding rock stress is in the range of 100m, the scope in which the surrounding rock stress is remarkably affected is 20～30m; The maximum increasing speed of bolts’ stress is up to 55KN/d, the maximum increment is 70KN, the maximum increasing speed of roof separation is 15mm/h, the maximum increment is 67mm. However, the high speed just kept for a short time. The change of the stress and displacement is of catastrophe characteristic.

Through using mathematical-physical model of gob flow field, distribution of oxygen concentration and velocity of air flow are determined based on COMSOL. The gob spontaneous“three zones” can be divided by the method of combining oxygen concentration with air leakage wind speed. And the simulated data is verified with measured oxygen concentration on the side of both intake and return airways. The results showed that the method is available and effective and the width of the oxidation and heat accumulation zone（OHAZ）in the gob of the long top-coal caving face is distributed more widely on the side of both intake and return airways for the serious air leak, which have certain guiding significance to prevent and control coal spontaneous combustion of the working face.

According to the engineering background of surrounding rock deformation instability in Mugua Coal Mine ore 103 segment transport Roadway, based on Ground Pressure and Strata Control theory, Mathcad software used to calculate the vertical pressure on this roadway, The force boundary of UDEC numerical modeling is established based on the results, establish UDEC numerical calculation model and optimize support parameters for this roadway, and put forward asymmetric support programs. The results of research show that: Mugua Coal Mine ore 103 segment transport roadway under high stress of legacy coal pillar of close-seam, and have very obviously asymmetric vertical pressure acting on both sides of the roadway(where the right side is 18MPa, the left is 11Mpa). Because of the stress environment and results of numerical calculation, put forward asymmetric support programs, coupled with the force status of the roadway, can significantly reduce the amount of deformation of the surrounding rock than the original symmetry support programs.

This article introduced the situation of overlapped areas of cropland and coal resources, farmland damage and reclamation treatment in the coal mining subsidence area with high phreatic water level; pointed out that the main problems in the process of reclamation treatment under the existing policies were lack of farmland loss-report and reduction system, unreasonable compensation standards, imperfect social security system of landless peasants, lack of land transfer policies and multiple taxes burden for the enterprise; proposed that established the farmland loss-report and reduction policies and related supporting policies were the permanent cure to the biggest difficulty for government, enterprises and landless peasants; and put forward suggestions on enhancement of the land protection consciousness, improvement in the mine and reclamation technology level, increasement of the treatment policy and financial support at the national level.

The coal mine is an important one-time energy. It is significant for research destruction movement and deformation caused by the coal mining, classical probability integration method as commonly used in subsidence prediction has its own superiority, but it can’t show the movement and deformation within the strata, and the key parameters only be confirmed by actually measuring it, it caused some difficulty to the prediction of mining subsidence. The study shows that the numerical simulation of no need to determine the complex parameters not only can display the movement and deformation of the surface, but also can shows about the interior the rock stratum.

The surface movement law caused by insufficient mining shallow buride coal seam is different with the sufficient mining, the paper was based on S1210 working face of NingTiaota coal mine, and conducted field research of the surface movement law of insufficient mining shallow buride coal seam, results indicated that ground surface settlement experienced stabilization stage and sudden change stage before startup, active and decline stage. Based on probability density function method, a MTLAB nonlinear matching procedure was established, by using measured data to match the predicting formula,the matching result was coincide with the actual condition. Based on the predicting formula, surface movement main parameters was calculated, the parameters was accord with the actual value, and has high reliability, and could provide reference basis for back stoping of other working surface or other similar insufficient mining, and could accurately predict the shape and range of surface subsidence basin caused by insufficient mining shallow buride coal seam.

In the condition of mining under thick alluvial, the surface subsidence and deformation have themselves characteristics and regularity. According to geology and mining condition in thick alluvium mine-area, cloud charts of strata vertical movement and surface subsidence curves are obtained in different conditions of alluvial thickness among 100m～350m. the relations are discussed about subsidence maximum subsidence W、subsidence coefficient q、thickness of alluvium, particular laws of the surface movement and deformation are analyzed in the condition of mining under thick alluvial, also the reasons are explained from movement and deformation mechanism of strata and surface. Then the subsidence law is obtained in the specific thick alluvium mine-area.

Although effective volume and empty volume of water sump are important to drainage safety of coal mine, there are seldom study on monitoring them, thus trouble in safety is hidden . This paper, according to the layer phenomenon in water and the structure of water sump, calculated effective volume and empty volume of water sump based on water level and slime thickness, and designed two floats level sensor and float combined with ultrasonic wave level sensor that could detect slime thickness directly or indirectly and water level, which provided reference to apply dynamic monitoring on water sump in coal mine.

Analysis models are established for a multi-functional heat pump unit (MFHPU) for mine cooling, district heating and waste heat recovery in different working conditions and formulae are proposed accordingly in order to study the performance of the MFHPU in heat supply and consumption. Then energy analysis and calculation are developed on theoretical working condition and real working conditions adopting real refrigeration agents. The research result shows: the difference between the input and output energy of the MFHPU system is small, the energy supply and consumption matches well, it is better to reduce condensing temperature, increase evaporating temperature and reduce temperature difference of heat transfer between heat exchangers of the MFHPU and cold or heat sources during design and application of the MFHPU, and the MFHPU has an optimal performance in the working condition wherein cooling and heat recovery are performed simultaneously.

In this paper, numerical simulations were carried out to study the optimal size of gas-liquid two-phase ejector using Fluent simulation software, and the influence of injecting pressure and outlet pressure to ejector conditions. The results showed that the jet nozzle diameter in ejector was affected and restricted by the factors such as flow field development, pressure characteristic curve and phase volume concentration, the nozzle diameter was in the range of 16 mm~20 mm considering these four factors; When the injection pressure was constant, gas flow rate, gas concentration and velocity decreased with the increase of the outlet pressure; When the outlet pressure was constant, jet gas phase concentration was on the rise with the increase of injection pressure. This will have a certain guiding significance to the design of gas-liquid ejector, and improve water jet structure, and perfect the hydraulic cutting seam technology.

The pore structure characteristics and fractal dimension of coal acquired from North China are investigated by using mercury intrusion method. The results show that the pore volume and specific surface area of coal are determined by development of big porous and micro porous respectively, and as the change of Ro,max the pore volume and specific surface area of coal change curves appear higher both end and lower middle; when pore diameter exceed range from 50.4 to 95.4, the pore diameter appear fractal characteristics and as the increase of Ro,max the fractal dimension present decreasing trend as a whole.

Two different coal samples were selected to perform traditional mixed flotation and classified flotation respectively and polynomial matching was utilized to build the functions of concentrate yield, concentrate ash content and flotation perfect degree with drug dosage. Through the analysis of this mathematic model it indicated that for Yulong coal sample classified flotation showed obvious advantage while for Wenshang coal sample classified flotation was not effective. Electrostatic interaction between high ash ultra-fine slime and coal particles of different size was analyzed to explain this phenomenon.

Stability reinforcement layout of southern high slope of Haizhou opencast mine was studied. Overall principles selecting stability reinforcement methods of high slope were established. Suitable calculation method was built, related calculation geotechnical parameters were given. Reasonable safety factor indexes were analyzed and confirmed. In consideration of situation of opencast pit in site, it designed the optimal slope cutting scheme, analyzed its stability, and pointed out necessity of second reinforcement. Aiming at safety factor and cost along with reinforcement measures of anchor rope, slide-resistant pile and foot consolidation, it make use of orthogonal design method to design and calculate the reinforcement optimization scheme so as to make the most optimal scheme. The research results can guide engineering design and construction in site.

Abstract: For the particularity of operating conditions of large yard conveyor, the article presents the basic principles of calculations of all kinds of resistances of belt conveyor in the design calculation and calculations to a variety of possible conditions. It applies DIN22101-2002 calculation method to a yard belt conveyor calculation. Six possible layout schemes of drive, brake and tension device are compared. Then it determines the best layout scheme and gives the design calculations.

The research on domestic sewage disposal by CAST is showed in this paper. The primary source of domestic sewage is offices and living quarters. The operation results show that the process has the advantage of stable operation, stronger resistance to shock loading, high efficiency of biological phosphorus removal and the low operation cost. The effluent is reaching the first class of Integrated Wastewater Discharge Standard (GB8978-1996) and the Design Criterion of Wastewater Recycling Engineering（GB50335-2002）.

Existing separation process of Sichuan Yimen Coal Mine CHPP can’t meet the needs of actual production any more, the transformation must be carried out. The CHPP has these characteristics: lots of ultrafine coal in RAW and handling raw coals in different ranks. This article analyzed the difficulties of the transformation and put forward the idea of “One Separation Process, Two Preparation Systems”, which can realize the respectively preparation systems for thermal coal and coking coal. Finally, this article analyzed the separation effects and economic benefits after transformation

To solve the problems of monitoring system under coal mine, which include the rational use of network resources, reduce energy consumption and improve transmission rate because of using a single network protocol, based on the mixed protocol zigbee and wifi, a new wireless sensor network monitoring system is designed in this paper. The non-video information uses zigbee protocol, via clustering type chain type wireless network to the ground monitoring center, while audio and video data information uses wifi protocol to the ground monitoring center. A combination of the two can reduce the high-cost and high-power problems which using the single wifi protocol brings and also solve the worse real-time issue when using the single zigbee protocol to the maximun. The actual application shows that the mixed protocol wireless monitoring system in this paper greatly improves the reliability and security of the system.

Abstract: In view of the current mine gas monitoring wiring complexity, communication difficulties and other drawbacks ,the underground gas monitoring system is designed based on the IOT technology . The core of the system is STM32 processor, the terminal detects child nodes is made of the gas sensor 、 the temperature and humidity sensor SHT11 and Zigbee wireless communication module, through routing nodes realize wireless data transmission. Field test data is transmitted in real time to the monitoring center using GPRS technology, Software platform is built with NI Labview, to achieve real-time monitoring of the underground environment and alarms. Test results show that the system is stable, low power consumption, accurate measurement, flexible distribution network.

In view of the types of Roof abscission layer instrument in Coal Mine at present, and according to the measurement principle of the roof abscission layer instrument and the way of recording roof abscission layer data in the actual, the paper puts forward an innovative system that adopts Zigbee technology , which transmits data. Substation and roof abscission layer instrument in every measuring position constitute an abscission instrument network, and through Man Machine interface of the substation, we monitor the state of roof separation in real time, and this way realizes automation and network of abscission layer monitoring，using the sectional digital capacitance sensor，improves overall measurement accuracy of the product and reduces the cost.

Abstract: To solve the problem of high dust concentration hazard caused by whole rock tunnel excavation，aiming at the rock dust hazards of Zhangji coal mine working face，the paper put forward to create a combined system which gives priority to froth dedusting，dust exhausting fan，assits with the grade purified water curtain and individual protection，and put it into application at the 1123(3)~1124(3) gas drainage lane. The results show that the average dust-settling effect is 92.5% and 96% for the total dust and respirable dust. Cooperating with individual protection and the water curtain，the combined system has achieved a good effect of controlling dust.

Analyze of the FBD series flameproof push-rotating axial local fan noise generation mechanism and original noise reduction measures, mainly based on the rotating axial fan noise sources and noise frequency characteristics, in as much as possible change the installation dimensions and structural design of the premise, put forward a new local fan noise reduction scheme, after a large number of experimental studies, by using the side air intake inlet structure design, changing the inlet line, and achieved good results, fans imports more than 15 dB noise reduction.

Combined with a matured theory and semi-empirical formula, this article calculates the structural parameters of none-pressure three-product cyclone with advanced approach, analyzes the effect of the structural parameters of the cyclone on process Indicators, and make optimized solutions to the frequently-occurred problems in production.

By analyzing the waste disposal system used in construction of rock roadways，an new type continuous waste disposal activity line was proposed，which include bucket loader，belt conveyor and mine cars，which realized the parallel operations of excavation of headings and transportation in roadways. Through analysis of the application effect of eight mining area pedestrian down the mountain，the authors found that the new type waste disposal system could greatly increase the efficiency of waste disposal，get rid of the link of temporary waste warehouse，solve the problem of waste disposal which was restricted by drivage rate.