The deformation characteristics of coal roadway with broken roof, its failure mechanism and its controlling countermeasures are systematically researched through field investigation, theoretical analysis and numerical testing . Research shows that the former support pattern is unable to enhance the stiffness of the lower strata of broken roof .It results protecting effect in support system was exploited and support system was destroyed one by one. Finally, the roadway loses stability. The blocks structure of roadway roof mechanical model is established and analysis shows that supporting by bolt and anchor can not satisfy the demands of supporting . The combined support “bolt/steel mesh/anchor plus grouting blot” was putting forward to enhance the of cohesion of construction surface and improve the mechanical characteristics of the broken surrounding rock which lead to support system would not fail.The engineering application presents that it can solve the large deformation of large secton coal roadway with broken roof which can provide reference for roadway support in similar geology strata.

In order to improve the lump coal rate, According to CEMENTER coal seam geological condition and equipment selection, Aimed at the main factors influencing the lump coal rate in production: Screw drum of shearer parameters,The production process and Transfer point in the process of belt transportation reprint way has carried on the detailed study, According to the results after the implementation, The lump coal rate on the basis of the lump coal rate increased by 8 ~ 10%, Coal quality were fully guarantee, And mastered the more suitable for the Mr. Montier coal mine geological conditions of production process, To ensure the safety in production of orderly, Make the mine under the condition of the market downturn still can achieve good economic benefit. At the same time, the effective implementation of this technique in ordos region geological conditions improve the lump coal rate of technology research provides certain theoretical basis.

Theoretical analysis, numerical simulation and field observation were used to define the rational width of coal pillar in Wangjialing coal mine. Based on different theories, a larger range of coal pillar width were obtained, and this proved that different theories had a strong dependence on the relevant parameters. Based on the theoretical analysis, FLAC 3D software was used for assessing different sizes of coal pillars. When the coal pillar width was over 20m, the stress concentration, the plastic zone development and deformation around the tunnel could be improved, which was good for the stability of the roadway. Based on theoretical analysis, numerical simulation and field observation, it was suggested that the existing 25m clear width coal pillar with a surplus capacity could guarantee the stability of the roadway. On the condition that the basic geological conditions in the next work face remain unchanged, the coal pillar width is proposed to 20m by strengthening supports and monitoring, and it is good for improving the availability of resources.

In order to prevent belt conveyor starts to slip, and analysis of double roller driven conveyor traction and surrounding angle distribution;Single drum drive does not slip and the second roller skid for the principle of dual roller drive, driven by a single cylinder and double cylinder is given starting coefficient calculation method;Given the automatic constant tension device installed conveyor drives the tension calculation method in different location, transportation and start to drive the tension coefficient are calculated through engineering examples, which can ensure the safe and reliable operation of belt conveyor system.

Dormitory as the important part of civil construction has a great contribution to coal mine industrial sites. The unit plan determining the overall space form is the basic structure of the dormitory. At first, this thesis gives a discourse about the composing of the unit plan, and then concludes three kind of unit plan by taking recent design practices as examples, including bathroom near the hallway, on the balcony or in the middle of the room. In the end, there is a discussion about these three forms from the perspective of scale and climate.

In order to figure out problems of low efficient of drilling-and-blasting and roadheader in hard rock strata which UCS is larger than 60Mpa, the feasibility study of application of TBM in shaft colliery was carried out. The machine was designed and manufactured specially to meet demands of methane-proof and shaft hoisting. The TBM was assembled and tested in underground assembly station and started stepping in the same location. Penetration, bolting, meshing and rock conveying were conducted simultaneously which guaranteed speed and efficiency of penetration. Measurement and monitoring data were collected for adjusting supporting parameters and establishing dynamic supporting system. The average penetration rate is 13.5m/d and the record is 30.7m/d, which is 5~10 times that of conventional drilling-and-blasting.

Daliuta coal mine creatively developed high efficient full face tunnel drivage machine and ancillary equipment, reformed the tunneling technology system, and improved the tunneling efficiency, at the same time efficiency has. But high efficiency face a variety of problems in the application process middle, restricted the further development of fast driving system, for example, bolter end top air safety, transportation system, blocking the lump step type self advancing tail walking deviation problem, ventilation and dust removal system optimization problem. Solving these problems have important meaning to further improve the rapid excavation system efficiency and practicability.

A water-inrush accident broke out in the main shaft of Wu-ju coal mine when it was constructed at -223.7 m level, the max quantity of gushing water was 360.97 m3/h, the depth of flooded shaft was 145.64 m. The construction technology of concrete waterproof pad under water was proposed, the underwater concrete waterproof pad was built successfully and the water-inrush accident was managed quickly and effectively. Compare with freezing method, it shortened the construction period and saved about 100 million engineering cost. The successful practice of this construction technology provide valuable experience for water-inrush controlling while shaft construction in the similar geological conditions.

In order to study the increased permeability effect of strata penetration deep-hole blasting in the high gas content and low permeability coal seams, taking No.13-1 seam in Huainan mine as the engineering background，a method, strata penetration blasting with coal-rock interface charging was proposed. In addition, explosion models for testing the effect of increased permeability were designed. When the charge exploded, the signal of dynamic strain between coal seam and rock formation were tested with the ultra-dynamic testing system and then crack distribution was observed. The results show that stress waves reflection stretching appeared in interface which lead to coal-rock interface separated, cracks and gas holes are interconnected, three-dimensional reticulation of gas drainage channels is formed. Meanwhile, the explosion caused a strong disturbance to coal seam and it works very well. This technique had great theoretical value and practical significance for strata penetration deep-hole blasting and increased permeability in coal seams with the high gas content and low permeability.

Abstract: According to the characteristics of comprehensive mechanized heading face, this paper have established k-ε-Θ-kp mathematic model to solve two-phasep flow of gas and particles in dust space with eulerian-eulerian method and eulerian-lagrangian method. Numerical solution of gas-particle two-phase flow was put forward. Combined with numerical simulation results, the forced-exhaust ventilation mode has been improved to introduce dust control technology with enclosed air curtain, optimize the design of the outer digging machine spraying device, choose preferably the efficient atomizing nozzle, develop a highly efficient chemical dusting agents and air curtain dust control devices. Eventually comprehensive dust control and remove system with enclosed air curtain is constructed in fully mechanized workface. At the same time, the system has been applied in railway laneway in the No.2 mining area of Xinzhi coal mine. It can effectively control the dust of working surface, It was determined that it was the work that the average dustproof rate of full dust and respirable dust reach 94.8% and 93.9%.

This paper mainly introduces the application development of underground coal mine air pressure self-help system,the use of air pump cooling,drain off water and oiling of equipment;The air pressure self-help system led to the fully mechanized working face upper corner,blowing off harmful gas;goaf gas sampling etc,to provide some reference for the coal mine safety production.

According to the incomplete samples of gas explore accident in underground coal mines from 1950 to 2009, the gas explosion has been a threat to coal mines. In order to explore the influence of unsafe act on the accident in the process of blasting operation. The mine blasting operation, divided into 13 procedures and 44 acts based on standards and field experience, is an act chain to explore safely. After taking a comparison between the unsafe acts in the 218 samples nearly 60 years and the safe act chain, then the management vulnerability in blasting operation in coal mines can be found. The result shows that such key procedure like “hole sealing” and key acts like “the first gas examination” cause 88% accidents, and that the main points to prevent gas explore accident during blasting operation is management vulnerability optimization.

Abstract: Through analyzing the general problems existing in the coarse coal slime separation technology and equipment, this paper introduces a new type of coarse coal slime separation technology, which has been achieved good effect in practical application.

For the mining subsidence induced by coal mining brings a series of environmental problems, On the basis of the understanding of the current subsidence governance situation, analyze the existing problem of coal-execavated subsidence governance. This paper puts forward four countermeasures that to strengthen the overall planning of coal-execavated subsidence governance, adjust the distribution of coal exploitation, raise governance funds in many ways, innovate coal-execavated subsidence governance mode, which has a certain guiding significance to promote coal-execavated subsidence comprehensive governance.

Mining pressure monitoring is carried out in gob-side entry retaining of Zhongxing Mine. Strata-pressure behaviors of working face and deformation laws of roadway which be in the secondary mining are studied by analyzing working resistance's changes of hydraulic supports and deformations of roadway. The results show that: The maximum dynamic load coefficient of working face, which reaches 1.757, occurs in the area close to the roadway which be in the secondary mining. So, the strata behaviors is most obvious in this area. Two ends of working face have longer periodic weighting length and duration, the duration can be 2.4~2.6 times longer that in middle of working face. Therefore, the two ends of working face are major locations where periodic weighting affects. When height of partial working face increases duo to the existence of extraction roadway, periodic weighting becomes not obvious, and this part always be in high roof pressure, so it is the key region of roof management. The deformation of side wall is 2.28~3.38 times which of the roof in the roadway, so the supports of side walls need to be pay more attention. In the roadway, when distance between working face and monitoring section is less than 10m, mining pressure affects strongly, when the distance is between 10m to 50m, mining pressure begins to influence, and when the distance is more than 50m, mining pressure has little influence.

Aiming at the question of the effect of high ground temperature environment in deep mine on limit parameters of coal spontaneous combustion, the method of temperature programmed experiment was used, and the experimental design of one coal sample was dealt with 40 ℃ constant temperature, the other coal sample was rose temperature from normal temperature was carried out to research the coal spontaneous characteristics, after calculation of the oxygen consumption rate, CO and CO2 generation rate, heat release intensity of the two coal samples, the change rules of limit parameters of coal spontaneous combustion were got. The experiment results showed that, the oxygen consumption rate, CO and CO2 generation rate, heat release intensity of the coal sample that was dealt with 40 ℃ constant temperature were higher than the coal sample that was rose temperature from normal temperature, its minimum float coal thickness and lower limit oxygen concentration extremum decreased, and upper air leakage intensity increased, and the rate of change with coal temperature almost linearly increased, which demonstrated high ground temperature led to the oxidation exothermicity enhanced of coal, thermal storage and self-heating was more easily, and the risk of spontaneous combustion increased.

The analysis is made about the drainage performance of gas wells under different combination of coal seams (5#、8#、9#) in Linfin block. It illustrates that the productivity under multi-layer production of 5#+8# or 5#+9# is better than that under single-layer production of 5# and multi-layer production of 5#+8#+9# or 5#+sandstone+9#. Based on the test data and theoretical calculation, the effects of interlayer geological condition differences on CBM well productivity are studied intensively. The result shows: the chief reasons affecting the productivity can be explained as the interlayer differences of hydrogeological conditions, pressure and permeability, gas content and cementation, and total resource.

Abstract: At present, the energy consumption has become a problem which cannot be ignored in the design of belt conveyor. Indentation rolling resistance and Idler rotational resistance has become the biggest influence on the running resistance of belt conveyor. Therefore, it is necessary to carry out research on the indentation rolling resistance and idler rotational resistance. Because belt speed is an important operation parameter, the study on the influence of the belt speed on the indentation rolling resistance and idler rotational resistance is meaningful. Since the majority of research , especially the research of indentation rolling resistance, are based on the theory and software simulation. Therefore, Author firstly designs a set of experimental device which can measure the value of both indentation rolling resistance and idler rotational resistance, subsequently, the research on the relationship between belt speed and indentation rolling resistance with idler rotational resistance can be carried out with the help of frequency transformer

Mine Hoist plays a vital role in the coal mine production, but with current harmonics at same time. This paper presents a new three-level NPC parallel active filter, which has a funtion of the DC hoist load harmonic compensation, while the limit on harmonic load does not meet the compensating device capacity, both reactive power compensation. The simulation studies have demonstrated the feasibility and benefits of secondary programs. For NPC three-level active filter key technologies are discussed. Propose a new voltage PLL technology, in the coal mine power grid transients and other environmental imbalances and still have an excellent lock capacity, improve system stability.

The process of the Mechanical/thermal dewatering of Victorian brown coal was explored at 150 ℃ and stepped pressure of 3-6-12-24 MPa. The moisture content of the product was 0.31 g/g dry coal and the reduction of the moisture was 66.3 %. During every pressure stage, the process could be divided to two stages: primary consolidation and second consolidation. In the process of primary consolidation, the interparticle and intraparticle moisture of brown coal was removed with high dewatering rate, which was the main stage of dewatering. In the process of secondary consolidation, creep deformation of lignite skeleton happened and caused additional volume reduction, but the dewatering rate was lower than the primary consolidation. With the pressure increasing, macropores and mesopores were destroyed gradually and it was harder to dewater. The rate of dewatering in both of the primary consolidation and second consolidation stages decreased with pressure increasing, but until 24 MPa, the moisture content was reducing, which means more moisture could be remove at 150 ℃.

Shenfu raw coal and vertical furnace semi-coke were used to be investigated.Using Nitrogen adsorption, XPS, FTIR spectrum and SEM to analyses the raw coal and semi-cokes, which showed that the specific surface area was larger and the pore structures were more developed of semi-cokes,compared with raw coal.Functional groups of semi-cokes and raw coal are similar while the contents are different.Facial functional groups have been changed after coal pyrolysis, semi-cokes facial C—C、C—O bonds were increased, C—H、C=O and O=CO bonds were reduced.

Abstract: Heat upgrading technology was the basis for the use of lignite to the depth, however, the severe fragmentation and pulverization of lignite, which occurred in the process, had been a key problem to prevent normal running of process. Based on the analysis of the causing reasons for lignite fragmentation and pulverization (water vapor behavior, volatile arising, mechanical force , heat processing parameters)in this paper , the influences in different drying / pyrolysis demonstration process were elucidated. According to the common problems of different processes, the key solving direction ,which included strengthen the basis law in research and innovative reactor design,was proposed.

Article use the t-test of single factors and triple levels to do analysis of variance with the slow determination ash content datas，which are achieved through three different particle sizes of pulverized coals，aiming to study The Influence of particle sizes to Ash Measuring. The results show that it not only will not influence the accuracy of Ash Measuring that modify particle sizes from 0.2mm to 0.25 mm, but also can save time，decrease power assumption，and absolutely promote efficiency.

Abstract: The paper briefly introduces the present situation of coal resources in our country, and analysis and study the resources distribution suitable for open pit mining and account for the proportion of coal resources, states the present development states and major development main body of open pit coal resources, and analysis and summarize the resource conditions of large opencast coal mine, and statistical analysis the main production area and recoverable reserves of the main development companies, overall evaluations the resource status、coal quality、resources hosting conditions、exploration degree、stripping ratio and external conditions of coal resources suitable for open pit mining, indicates the mining area of the most suitable for open pit mining and future development direction, which has certain significance for studying the mining of open pit resources.

The paper gives a main introduction about the stament of the device concerning dustproof and waterspringkle in our current main shaft hoist skip unloading point,as well as the imperfections of existing unloading point dustproof instruments. According to the conveying characteristics of mine coal flow system as well as ultrasonic sensor ,Tthis passag unfolds a design of an automatic dustproof and waterspringkle device on the basis of ultrasonic sensor detecting skip unloading point. As a result, this device has been proved to be sutable for practical use in mine dust control system.

According to fully mechanized coal face matching principle in the thin coal seam, these parameters in three machines-hydraulic support, shearer and scraper conveyer- are further optimized by using genetic algorithm. Using Xiandewang mine as an example, relevant comparisons and summaries has been made about optimized parameter values. Finally, simulation and test data verify the correctness and rationality of evaluation calculation.

In order to facilitate the manufacture and inspection of cutting head of roadheader, a mathematical model for pick location is established. Then, using the two point method, the inspection of pick’s space angle positioning parameters is transformed into the inspection of coordinates of two points at the pick axis, which also is checked at the machine tool coordinate system. At last, the fixture for pick location is designed, which can decrease the error of pick holder welding.

The load conditions of three kinds of working conditions include full load bending, braking and sideslip are analyzed to determine the loads and constraints under different working conditions. Then the strength analyses for each working condition are carried on by ANSYS Workbench. According to the results, larger stresses occur at the inside, outside and under the surface of steel plate spring seat. The results show that the maximum stress of braking is beyond the yield limit of material. So front-axle beam cannot meet strength requirement. Then the improvement scheme is proposed, and the strength analysis and verification are carried on again.

By summarizing the status of coal economic development mode status of coal economic mode, problems in taxation mechanisms of coal economic development mode are found out , and finally, from many aspects, right resources in forming coal economic development mode changes are targetedly proposed. In doing so, the paper focuses on seeking more scientific and reasonable coal development mode based on changes in taxation mechanism.

In China, the power coal is the main commercial coal. In order to achieve efficient use of power coal, reducing environmental pollution and enhance the competitiveness in domestic coal market, it is very necessary to emphasize coal quality evaluation and management. In this paper, firstly, it is analyzed the impact of coal quality indexes. Base on safety, economy, efficiency, and environmental indicators, power coal quality evaluation system is established. Then, according to power coal sales and quality data of 17 key coal enterprises, the power coal is divided into three grades. The results show that high-quality coal is mainly from north area, east area and northwest area; sub quality coal is mainly from north area and northwest area. On the basis of quality evaluation results, suggestions for future coal production, sales and use are provided to enhance the whole level of quality of power coal.