Aiming at the problems of coal roadway large-range deformation and breakage caused by unreasonable coal pillar dimension in fully-mechanized working face with thick coal seam. Taking advantage of the engineering analogy theoretical analysis and numerical simulation to find the reasons for the instability of roadway and the reasonable width of coal pillar. In the spot, coal pillar optimization experiment was carried out to verify the results. The results show that it was not suited for narrow coal pillar under the conditions of geological and production in Chahasu coal mine. It is proved that the main existed difficult problem of roadway support was caused of small pillar width for roadway maintenance has caused the bearing stress superposition issues. Through compared with the distributing rules of stress, displacement and plastic zone distribution with different coal pillar width, ultimately arrive at the conclusion of the coal pillar width is 35m, and this optimization design has an obvious advantage in engineering and economic terms.

Based on elastic-plastic theory, the interaction mechanics model between shaft lining and surround rock has been created.In the condition that stress and displacement at the boundary surface are equal, the displacement and stress equations of shaft lining and surround rock in the elastic and plastic regions have been derived, then the formula for calculating the thickness of shaft lining was obtained.Discussed the relationship between the resistance of shaft lining, plastic zone and displacement,the force on the elastic-plastic interface and the geometry.Influence on thickness design caused by the physical and mechanical parameters of surrounding rock have been discussed.

The level of coal production efficiency directly determines the cost and competitive ability of the coal mine. Based on the comparative study on the coal production efficiency of main coal countries in the world, this paper analyzes the reason of low efficiency of coal production in China from the resources, mine management mode and management level and other aspects; analyzes the internal and external competitive environment of China's coal market, puts forward some advice for improving production efficiency and reducing capacity of coal industry in China.

Based on EZMac Protocol,a real-time environment monitoring system was designed for surveillance of gas concentration,O2 concentration,CO concentration,CO2 concentration ,temperature and humidity in the coal mining face. Taking a radio frequency chip SI4463 as the key part of the monitoring system,the environment data of coal mining face can be acquisited, displayed, stored,wireless routed and transmited with the wireless EZMac Protocol, so as to monitor the environment data of coal mining face that the wireless network scope can cover.

The mining refuge chamber must be monitored O2, CO, CO2, CH4, temperature, humidity and other environmental parameters. According to the requirements of China, it must be ensured that not less than 2 hours of standby time of coal mine safety monitoring system after AC power failure according to the conventional coal mine safety monitoring system requirements, and the standby time of refuge chamber monitoring system must ensure not less than 96 hours without AC power, more stringent and longer time requirements is proposed to the standby power. The national standards for explosion proof of GB3836 allowed only using nickel-cadmium battery and potentially nickel-hydrogen battery in explosion-protection cavity, and there are disadvantages of low voltage and small capacity, it is not suitable for high power applications. This design according to the characteristics of distributed monitoring system equipment proposed distributed standby power supply structure, design a small power intrinsically safe backup power, and it was installed between the intrinsically safe power supply output terminal and the intrinsically safe apparatus. Test results show that the new intrinsically safe backup power has safety monitoring equipment to provide standby power supply for a long time, battery with the use of high efficiency, small volume, light weight, cheap price, provide safe and reliable power supply for refuge chamber monitoring system.

In order to provide the reference for the coal mine production in the water shortage area, this paper studies the underground drainage treatment technology and equipment. This paper introduces the improvement process of the patent, which is "Swirl coagulation Clarification + Mechanical Filter + Disinfect", and the drainage of the mine enters into the pre settling regulating tank, regulates the water quantity and the water quality, and then enters the core processing unit. A complete set of processing equipment using the PLC+ PC control system to ensure the smooth operation of equipment. The test results show that the Xiaohuigou coal mine water treatment technology is mature and reliable, easy to operate, easy to manage and maintain. Core processing technology and equipment can effectively remove suspended solids, reduce turbidity, water quality has reached a predetermined target. The utility model solves the contradiction that the water shortage affects the production of the small back ditch Xiaohuigou coal mine.

Aiming at the problem of partial coal mine, which the high-salinity mine water quantity is big , difficult to deal with and has direct discharge of environmental impact, combining with the characteristics of high salinity mine water, this paper puts forward the main commonly used treatment technology and makes a comparison of different technology. At the same time, combining with the water consumption characteristic of the mine coal self, the surrounding enterprises and the ecological restoration, the comprehensive utilization of the resources of the sub quality is put forward, which provides some ideas and references for high salinity mine water treatment and comprehensive utilization of the similar coal mine.

This article discusses the calculation parameters and steps for model selections when shaft freezing taking advantage of unit air heater.And carrying on analysis by selecting five different shaft freezing schemes. Striving to find the best scheme by comparison of indoor temperature of heap-stead under different scheme conditions,inlet wind velocity,the effects and equipment purchase cost of indoor heating system and so on.

Based on the influence of the mining disturbance of the working face in the West Wing of a certain mine, the deformation and failure of the working face is affected seriously, and the integrated control technology of the hydraulic fracturing roof and grouting reinforcement is put forward. According to the in-situ stress and the coal and rock mass in situ test results, using UDEC numerical simulation software simulation analysis of the hydraulic fracturing and grouting of roadway surrounding rock deformation and the influence of stress distribution, and industrial test in the field of roadway. The research results show that: the comprehensive control technology of hydraulic fracturing and grouting reinforcement can effectively reduce the stress and deformation of surrounding rock, and shorten the time of roadway stability. The research results provide an important basis for the design of roadway support under similar conditions.

Based on the changcun mine geological data and characteristic of floor heave of 1#roadway in S6 mining area, suppot scheme in rock and floor heave control is proposed.Mechanics theory is used to analyze the stability of concrete antiarch composite structure and floor surrounding rock, and the design parameters of concrete structure are tested, it shows that the concrete antiarch composite structure is stable and the design parameters of concrete antiarch composite structure are resonable; Through the numerical simulation analysis of the support scheme and situ engineering tests, actual amount of floor heave is 135~194m, far less than 500m that using the original support scheme, and the floor heave support structure is stable, not exceeding the limit load, which proves the feasibility of the scheme of controlling the floor heave by bolt-concrete antiarch structure.

The distances from 102 coal seam to the confined aquifers of the 5th limestone and the Ordovician limestone were 23.9m and 49.6m.By theoretical analysis,that coal seam floor failure caused by mining 9th coal came through 10606up working face,and increased 23% and 12% to each water inrush coefficient of the confined aquifers,so the threat of water inrush in working face gone up.For the safety of 10606up working face and based on the actual production of mine,we employed the floor grouting to inhance the aquiclude.Combined with grouting diffusion radius and water yield of the 17 grouting drills and mining situation,the thickness of aquiclude increased and zone of aquiclude got inhanced,so the minning safety was guaranteed,and could be used for reference in similar situation.

High level drilling was one of the effective methods using for gas in goaf. With characteristics of controlling and the long effective part, the high level directional drilling used to gas drainage was a tendency. But the study on the application effect of the high level directional drilling was less. Base on the successfully developed of the high-power rig, four drillings were done at Tingnan Coal Mine. And then they were enlarged to 153mm. Through the analysis of the flow and concentration of the gas from the holes, it found that the flow of the hole had a relationship with the distance between the hole and the stopping line. Even the extraction rate compared with the same high mining drainage was still a gap, but the gas emission per unit area had a big advantage.It was a new way of thinking for the gas control in upper corner.

Puzzles mine roadway floor heave governance seriously affect the safety of mining operations mine for artificial as a low bottom efficiency, labor-intensive and so the status quo, developed WPZ-55 / 50L roadway repair machine, with a high degree of mechanization, construction and high efficiency, low labor intensity, and grew up in a Buddhist temple in Shaanxi Coal Bin conducted a field test and promote the use of good results. And according to the characteristics of the construction site, summed up a set repair machine since the end of the construction process for the standardization of the construction machine repair has laid a good foundation.

In order to cross fast an outburst coal seam overburdening area of liziya South Second mine 3101 mining face with safety and economically, in this paper ,according to the difficult conditions of average inclination of 48°,soft roof and floor rock, 120m continuous outburst collapse area, we determined to use the way of detection of void area in floor drain and Grout filling. After the implementation of the scene,The results show that the construction scheme not only can successfully go through the outburst coal mining face collapse area, but also has significant economic benefits.

Gravity separation is the main method of coal preparation, therefore, it is important to evaluate and predict the effect of coal preparation. However the key problem of gravity effect prediction is how to determine the distribution rates of the density grades. It is complicated to predict the rate of product quality and quantity through the existing calculation methods, which should calculate t through the approximate formula and then check the distribution rates of the density grades through distribution index table. It is found that a mathematical model of "S" shaped curve based on the research of the distribution curve was established to predict the product of the gravity separation of coal, which can evaluate the effect of gravity separation conveniently and accurately.

Deformation monitoring is carried out in gob-side entry retaining of Zhongxing Mine. Floor heave laws which be in the firstly and secondary mining are studied by analyzing working resistance's changes of hydraulic supports and deformations of roadway. The results show that: Deformation of floor heave in Gob-side Entry Retaining related to multiple factors, forms and formation condition, the condition of surrounding rock and supporting water conditioning are important factor of floor heave. According to the floor heave of monitoring data, the variation of the floor heave with the mining face is divided into four periods: excavation and the stability, firstly mining front support influence period, firstly mining post influence period and secondary mining front support influence period. Among them firstly mining post influence period and secondary mining front support influence period produce more than 90% of the floor heave. The secondary mining effect of floor heave is far greater than the firstly mining period.

Based on Chang Lebao coal mining reasonable mining size under reamer-pillar coal mining, this paper studies pillar stability by theoretical analysis、numerical simulation and physical simulation. The results show: The existing “mining 10 leave 8” coal mining of Chang Lebao can not guarantee the permanent stability of pillar, The leaving pillar all enters plastic failure under numerical simulation, all leaving pillars occur group instability under physical simulation. When the mining width is 10 meter under reamer-pillar coal mining of Chang Lebao, the leaving width at least is 10 meter. The pillar elastic nuclear area rate is 50.0% under the “mining 10 leave 10” mining method in numerical simulation. This result exceed the 31% of field statistics pillar permanent stability about pillar elastic nuclear area rate in Yu Yang area. The stress distribution of coal-pillar presents gently saddle type. The design scheme can guarantee the permanent stability of pillar and provide reference for the wester mines to protect water resources.

In order to control rock deformation and keep surrounding rock stability and safety, based on the engineering background of 5204 roadway 8204 working face of Coal Mine, experimentally study on thick coal seam small pillar along gob roadway. Adopting roof bolt, anchor cable, metal mesh, W-type steel band and steel-anchor cable composite beams support, during driving roadway. Because the stability of roadway surrounding rock is affected by mining, the strengthening support is applied in the stress concentration region, coal rib side and small coal pillar side. Based on the in-situ observation of roadway deformation, 5204 roadway support way is scientific and reasonable, safe and reliable. 8204 working face has been done, controling surround rock achieves good effect.

Underground coal dust is harm to miner while it has a great security risk, dust suppression have great significance. The author aims to study polymer Surfactants as the main agent of foam dust suppression agentto to reduce the concentration and damage of coal dust. This experiment was the graft copolymerization of corn starch and Octadecanol, in order to synthesize surfactant, by orthogonal test to determine optimal feed ratio is 1:1.5 of oxidized starch and Octadecanol, the temperature is 70 ℃, the heating time is 8h, the solvent is 55ml. The wetting and wetting rate of this surfactant compared with sodium lauryl sulfate and myristyl trimethyl ammonium bromide were preferred. The surfactant as the main agent,through experimental study screened surfactant/foaming agent/flocculant system the optimal formula for the dust suppressant, detecting its wettability, cohesion and water retention on coal dust, detemined the optimal ratio of surfactant, polyacrylamide and sec-octyl alcohols was 7:1:2. The foam dust suppression agent preparation process is simple, the price of raw material is low, can very good wetting dust, improve the efficiency of dust suppression.

In order to reduce and prevent the occurrence of coal mine rescue accident, this paper mainly adopts the method of accident statistics and analysis to study the accidents in coal mine emergency rescue. Researching on 25 larger and more rescue accidents which occurred during the period of 2000-2015 shows that the main job types of accidents is gas explosion accident rescue and fire accident rescue, and the main cause of casualties is poisoning and explosion shock.In order to find out the specific reasons for the accident of coal mine rescue, using the "2-4" model to study the unsafe act reason in 12 detail described accidents. Results show that the first step to reduce unsafe actions is to control the illegal action; The first step is to reduce the illegal behavior is to reduce the high frequency unsafe actions like “Into the affected areas with inadequate equipment” in “illegal operation” part and “No strict treatment plan and safety technical measures” in “Illegally directin” part, and so on.

The model of 2JTP one rope winding mine hoist is established the 3 dimensional model with UG and the finite element model with ANSYS Workbench. Then, the first six natural frequencies and principal shapes are calculated in the modal analysis of main shaft device .And then the dangerous frequency range and the amplitude-frequency characteristic are determined through the harmonic response analysis.It also illustrates the limitations of harmonic response analysis.The results of analysis provide the basis for fault diagnosis and structural optimization design.

According to the structural characteristics of boom of mechanical excavator boom, through the statics analysis with ANSYS workbench software, the position of crack generation determined; the propagation of semi-ellipse crack is imitated on the structure surface of boom with the method of finite element, stress intensity factor range of different crack length obtained and its function relationship with crack length matched. According to the Paris formula of fatigue crack propagation theory, the life of boom from the crack generation to the critical length of the crack under the single influence of a certain alternating load Δσi is obtained. Finally, recombining the stress—time history at the hazardous position of boom obtained from the automatic dynamic analysis of mechanical systems (ADAMS), the crack growth life of excavator’s boom is worked out on the basis of Miner rule.

To investigate the extension characteristics of coal samples semi-submitted by liquid nitrogen with different water saturation, the anthracitic coal samples taken from Shanxi province were semi-submitted in liquid nitrogen with the self-made experimental setup. The ultrasonic velocity change and the cracks’ width extension of coal samples subjected to liquid nitrogen were tested. The results show (1) the saturation of coal samples has great effects on the cracks’ extension subjected to liquid nitrogen. The ultrasonic velocity change and the cracks’ width extension of the saturated coal samples are maximum, Those of the semi-saturation coal samples become worse. Those of dry coal samples are worst. (2) The nearer to the surface of the liquid nitrogen, the greater the temperature change of coal samples is. And there is much more significant effect of liquid nitrogen. (3) The main reason of the cracks’ extension of the saturating and semi-saturation coal samples is the frost heave pressure caused by the phase from water to ice. Thermal stress due to temperature gradient induces the cracks’ extension of dry coal samples.

When using 3D laser scanning to obtain the moving and deformation of highway in the mining area,because there is no observation point, the light pole on both sides of the road are selected as the characteristic features, through the comparison of different time coordinates change of light pole center axis, calculate the horizontal movement and deformation of highway. According to the characteristics of the point cloud of the light pole, We derived extraction model of central line of street lamp pole, using genetic algorithm to extract the central line of the street lamp pole, and analyzed the influence of the random error, gross error and the point cloud observation is not comprehensive on the extraction of the central line of the algorithm. The research results show that the method of calculating the coordinates of the center of the road lamp accuracy better than 1mm, and has strong anti-interference ability.

In order to improve the using efficiency of gasification residue and maximize the resource utilization. Different kinds of residue generated from Texaco gasifier and GSP gasifier as objects were researched. Basing on necessary measures includes grading?analysis, determination of loss on ignition, XRD、SEM, FTIR and BET to investigate particle-size distribution, content distribution, loss on ignition as well as morphology characteristics of surface of coal particles of coarse slag and fine coarse. Results show that residual carbon content of fine slag is higher than that of coarse slag; coal particles surface in residue of two pressurized gasification units produce well-developed pore?structure, spherical molten minerals adhere to the surface of coal particles, and changing of organo-functional groups of coal particles surface is researched; minerals in residue are existed as inert materials and they are presented with random crystals; surface area of coal particles from coarse slag is higher than from fine slag.

The coal mine roadway roof separation is a separate internal structure of rock, monitoring of roof subsidence is an important content of mine pressure monitoring. Aiming at the problem of roof subsidence, it is proposed that the separation distance convert into the big displacement sensor. To derive the relationship between the displacement and the semaphore ,and design the multi point roof separation indicator. It was applied to Maying Mine of Zhongmei Coal Group．With the analysis on the data obtained，the roof separation conditions of the roof in the air retuning gateway of No.9103 coal mining were in detail accurately mastered. The minimum roof separation can be measured is 0.19mm. It could provide important technical support to the roof classification and the optimization plan of the gateway support.

Abstract：On the basis of tradition groove turning device，The design scheme of the new type of vehicle slot device is completed，and the advantages and disadvantages of the two are compared.；establishing mathematical model of new groove turning device.Using the finite element analysis software, check the new type groove turning decice strength and stiffness。The results show that the operation of the new type groove turning decice is simple, efficiency and high precision, can meet the strength and stiffness requirements.

For existing mine gas outburst parameter measurement accuracy is not high, pressure low resolution, complex operation resulting in decreased accuracy of measurement results and other issues, a portable mine gas outburst prediction instrument is designed to resolve an index to measure the gas analytical indicators K1 as the main function. STM32F103ZET6 is the control center of instrument, high-precision digital gauge measuring sensor MEAS1220A outburst pressure , 24 precision A/D converter ADS1218 is used to converte the sensor output voltage into digital signal and digital filtering, A least squares fitting method is used for static calibration sensor. Measurement accuracy is greatly improved. Actual measurements under the mine show that the instrument has the features of measurement accuracy and high resolution, stable performance, easy operation, low power consumption, fast response and accurate forecasting results.

The paper analyses why the cutting unit’s hydraulic cylinders of some imported shearer frequently fail to run properly from the design point of view. The causes, which will lead to oil-leakage, etc., conclude the cylinder gland’s sealing O-ring is easy to be damaged during the action of its assembling, the width of the cylinder gland is relatively small and the bending stability of the piston rod exceeds its critical value. The paper puts forward corresponding improvement projects. The similar faults don’t occur to new-made hydraulic cylinders any more utilized the improvement projects. The improvement projects help to solve practical difficulties of the coal mine and provide basic research materials for the high-end development of imported shearers.

Construction contract risk assessment is the most important process of construction project contract management , how to carry out the construction contract risk assessment effectively is one of the important subjects about the existence and development of the construction unit. Based on the theory of contract life cycle this paper established construction contract risk evaluation index system paper through the literature review method, and then by means of correlation functions of structure element, determine the matter-element classical domain, joint domain, establish extenics evaluation model of construction contract risk, analyze and determine the weight coefficient by entropy method in quantitative evaluation of the construction contract risk grade, finally, evaluate X company’s construction contract risk by the model. In short, the objectives of the paper is to provide the theoretical base for the research and application of related field.

The present situation and development trend of coal based synthetic natural gas (SNG) industry in China were introduced, and the influence of carbon tax on the coal based SNG investment project was analyzed. The influences of carbon tax rate on the product cost and the internal rate of return of coal based SNG project were discussed. It was pointed out that if the carbon tax rate reaches up to RMB 80-100 yuan/t, the cost of coal based SNG would lose competitiveness, and the economic feasibility of coal based SNG project would be greatly reduced.

The paper introduced the current situation of coal science and technology development in China，combined with the economic development trend and policy guidance，such as China's New Normal，energy revolution and strategy of innovation-driven development, analyzed the new situation facing the coal industry development in China，discussed the development trend of coal science and technology in China, could provide the decision-making reference for the development of coal science and technology in China in the future.

Based on the characteristics of the coal mine fire control engineering projects on EPC pattern, through the application of system decomposition, brainstorming and similar engineering experience, risk factors were summarized and classified, and different coping strategies were applied for financial risk, quality risk, security risk and schedule risk, existing in different stages of contract negotiations, procurement, subcontracting, project construction of the coal mine fire control engineering project based on EPC pattern, to provide protection for the smooth implementation of the project.