In light of the deficiencies of the original minefield development plan for the SDIC Hami No. 1 Mine，combined with various factors affecting the selection of minefield development plans， the original minefield development plan was optimized. According to the characteristics of the coal mine construction project and the actual production，Adopting the present value method of the overall comparison method as a specific comparison method，through the technical and economic analysis and comparison of the two development plans from the three aspects of construction period, production period and life cycle, shows that the optimized development plan is more reasonable. Through the application of the overall comparison and selection method，it provides an effective solution to reasonably determine the field development plan.

In order to solve the problem of over furrow mining in shallow seam with ultra thin bedrock, the paper takes the design of crossing ditch mining plan for 30108 and 30110 working face of Yanghuopan coal mine in Shenfu mining area as an example. taking 30108 and 30110 working face of Yanghuopan coal mine in Shenfu mining area crossing ditch mining design as an example, discussed the necessity and feasibility of crossing ditch mining, combined with research surrounding similar coal mine, put forward three feasible crossing ditch mining scheme. From the security, technical and economic aspects of the programme to be selected, Scheme that taking measures of covering soil in ditch，Paving flexible network in working face and Pressuring ventilation is an effective scheme of Yanghuopan coal mine, and provides a new solution for the similar mine.

This paper aims to study the influence of the dynamic change of water level with time on the choice of miners' escape route when the mine flood occurs, and researches on the dynamic shortest path algorithm in the selection of mine flood dynamic path. Based on the block-type velocity curve model optimized the escape route selection mathematical model.In order to judge the influence of the continuous change of water level on the choice of the miners' escape route, divided the time period we studied, and obtained the time equivalent lengthaccording to the average escape speed in each roadway under different time periods, which is used as the weight of the adjacency matrix.This paper breaks through the drawbacks of the traditional Dijkstra algorithm that can not be effectively used in the dynamic environment in mine flooding optimal path search, and realizes the application of improved Dijkstra algorithm to dynamically select the optimal path during mine water inrush time,which has higher practical value and accuracy ,and it has great significance in the later mine virtual reality / augmented reality flood simulation application .

There are some problems in traditional voice system of coal mine working face, for example, analog voice signals are unsuited to long haul transmission and easy to be disturbed, battery power is consumed quickly, loss of transmission line leads to super low terminal voltage, too much invalid broadcast causes power waste of intrinsically safe power supply, etc. In order to solve above problems, an intelligent voice system of coal mine working face was proposed which was based on digital voice signal transmission. Hard circuit scheme of the system was introduced as well as dynamic management scheme of voice device. The system takes CAN bus as transmission carrier of digital voice. Main controller collects status data of voice device real-timely through CAN bus, and adjusts parameters of charging current and broadcasting volume of voice device according to different rules. The industrial test shows that the system can run stably for long.

A kind of monitoring and control system of coal-mine safety is put forward, which takes CAN bus as the communication network among field equipments, and AT89C51 as controller of intelligent node. The overall system architecture is presented, and further more emphases are put on implement of hardware circuit of intelligent node as well as the way of software design. The designed system is simple, flexible and reliable. Therefore it is worth while to apply the system.

Abstract: Combined with the current technical status that a large number of low-concentration gas and ventilation air methane in the coal mining area cannot be effectively utilized，the author introduces in detail the design of safety mixing and regulation using low concentration gas storage oxidation. Explaining the principle and technical requirements separately，putting forward specific technical indicators，and introducing the application of system engineering about safety mixing and regulation using low concentration gas storage oxidation. Design and operation of field applications showed that the system is safe，reliable and stable. It can meet the gas demand of gas oxidation comprehensive utilization project.

Abstract：In order to effectively control floor heave of water-absorption-expansion soft rock roadway，the author have analysed floor heave mechanism based on double factors of loading and water conditioning. Pressure-relief was proposed to control floor heave.A mechanics model for pressure-relief was established. The method of determining the width of pressure-relief was given. The stress distribution and displacement of roadway surrounding rock at different depth of pressure-relief are studied by means of FLAC-3D software. The parameters of pressure-relief are further determined. Studies have shown that adoption of pressure-relief reduced stress concentration effect of roadway angle and transferred vertical stress of the floor to deep. It is the flexure deformation of the diaphragm wall of pressure-relief that absorb the deformation of the floor. Field application has shown that adoption of pressure-relief and pressure-relief parameters can control floor heave effectively.

Based on the engineering practice of the 90111 Transportation flexible template gob-side entry retaining，combined with the stability of the surrounding rock and the special process optimization of the hard roof. The hard roof of the top working face was suspended. To deal with the problem, optimize the construction process of the flexible template gob-side entry retaining and optimize the parameters of the roadway. The effect of practice is well. The various supporting and flexible template gob-side entry retaining achieve the desired results and achieve good economic benefits.

Aiming at the problem of low drilling depth and low porosity in borehole construction of soft outburst coal seam, this paper analyzed and summarized some technical methods and problemsdifficulties existing in drilling construction of soft outburst coal seam, and put forward a high rotation speed wind pressure spiral composite slag discharging technology，the technological principle was expounded and the technological parameters of high speed compound slag drilling were analyzed and determined. The practice shows that the high speed drilling BHA and supporting with 95/60.3 plug-in sealing type spiral drill pipe and 98 arc-shaped matrix PDC bit, hole rate increased to 70.6%, the drilling depth is also significantly improved, also it provided referencepractical experience for drilling in soft outburst coal seam.

It is influenced by the forward support pressure for the overshoot of the fully mechanized working face,The area of plastic damage zone in the hollow roadway is expanded,Easy to cause coal wall sheet and empty roof collapse problem,Using numerical simulation software,The stress distribution of surrounding rock was analyzed and compared,The stress peak of the surrounding rock of roadway is obviously reduced after the empty alley filling, and the empty lane fill improves the stress state of the surrounding rock and reduces the stress value of the surrounding rock.Based on the scene situation, the filling construction scheme of high water materials was determined and the industrial test of the filling and filling of the fully mechanized face was carried out. Results show that the working face by filling fills up the lane area during the working face roadway roof subsidence of two consecutive a maximum of 146.8 mm, the maximum amount of drum at the bottom of 195.2 mm, drums left for a maximum of 49.8 mm, to help drum right out of the maximum amount of 82.2 mm, roadway deformation does not affect the normal mining working face, the strong to protect the safety of working face through empty lane area.

In order to study the effect of pressure relief on coal body by hydraulic punching, the high gas geological conditions in Yu Wu Coal Mine are taken as the engineering background, and the research is carried out by the combination of theoretical analysis, indoor experiment and on-site industrial verification. The results show that the process of hydraulic punching mainly through two layers of macro cracks and micro pores to realize the effect of pressure relief to the coal body; the field hydraulic punching effect test shows that the attenuation coefficient of the gas flow in the bore hole is 0.003, only about 1/7~1/8 of the common borehole, and the construction area of the punching measures. The efficiency and effect of drainage are obviously better than that of common drilling area. It is indicated that hydraulic punching technology can effectively improve the drainage efficiency and ensure the safe production of the working face, which is an effective way to solve the problem of pressure relief and permeability enhancement in underground coal seam.

According to the problem of high gas in TangShan mine, the source of gas is explored from many angles, Without affecting the progress of the project and minimizing investment ,The comprehensive gas control measures, such as increasing the air volume at the working face, gas drilling and drainage in the head-on construction of the working face, and improving the tunneling technology, have been adopted, and good results have been achieved, which opens up a new way for gas control in high gas long distance driving face. Key words: The long distance ; driving face ; gas governance

This paper studies the LoRa technology and its related characteristics and advantages, and analyzes the application form and methods of LoRa technology for coal mine. As a low power remote communication technology for Internet of things, LoRa technology uses a number of technologies such as spread spectrum modulation. It takes into account the problems of low power and long distance communication. It has the characteristics of long distance networking, low power consumption, low cost, low rate and large scale. It can organize network through Transparent transmission, Private protocol and LoRaWAN protocol to realize remote networking communication. In the coal mine, a large number of wireless networks have been used to realize such applications as monitoring, positioning and communication, but various technologies (such as ZigBee network) have much problems, especially for remote and low-speed networking, LoRa technology is a very ideal solution at present.

A study is carried out in the slurry recovery system of Majialiang preparation plant of Datong Coal Mine Group. The particle sizes of the overflow of classifying cyclone, the underflow of waste coal high-frequency vibrating screen and the coal slime to be filtered by pressure filters are analyzed and the reasons to the problem that the coal slime contents high ash are discussed. As for the slurry to be filtered, the hydrocyclone is used in the study of reducing its ash by gravity separation. And as to primary slime, flotation effects of many agents on it are compared and studied. Finally, three methods to reduce the ash of coal slime in the steam coal total preparation plant are found, which are pressure filtration of coal slime with high ash separately, gravity separation of coal slime and flotation of coal slime with good quality flotation agents.

To solve the problems of gas overrun at the upper corner in full mechanized mining face and spontaneous combustion in the goaf of Zhengbang coal mine, the horizon position of high level gas drainage gateway was analyzed from aspects of gas controlling, spontaneous combustion and gas flow field. It was found that the best horizon position of high level gas drainage gateway was K2 limestone floor, which could not only reduce stopping effect of gas transportation by limestone, but also exert a better extraction effect of high level gas drainage gateway. Furthermore, this floor could ensure the stability of the three-horizontal zones in the goaf, and effectively prevent its spontaneous combustion. The optimized horizon position of high level gas drainage gateway was verified by measured data.

Abstract：In order to ensure the safe and smooth mining of the 29 mining areas,the feasibility of the Taiyuan Formation limestone water drainage in panel 29 is studied;Through the water pumping and pressure releasing test on the bottom plate of the panel 29, the hydrogeological parameters such as the permeability coefficient of the main water-bearing section of the bottom plate are obtained; the well group disturbance theory and the unsteady flow theory are further used to predict the feasibility of floor drainage. The results show that the reasonable drilling arrangement and water release help lower the water table of the limestone aquifer, and the effect is remarkable. and it has practical feasibility. At the same time, it is of great significance to innovate the water control technology and reduce the cost of water control engineering.

Based on the statistics and analysis of a large number of documents, the spatial-temporal characteristics of shallow coal seam surface subsidence under fully-mechanized coal mining （fully-mechanized top-coal caving）are summarized, and the mechanism of surface movement is explored. The results show that, when the depth-thickness ratio is less than 40, the unexpected surface subsidence increases, the regular surface subsidence decreases, and it has two iconicity of unexpectedness and continuity, but it still has strong regularity generally. The unexpectedness is mainly manifested by the discontinuity of surface movement in the collapse pit, the collapse trough, the fissure and so on, as well as the occasionality of surface movement lasting time, the sinking quantity and so on. In general, the greater depth-thickness ratio is, surface subsidence continuity is the stronger, the smaller the depth-thickness ratio is, and unexpected surface subsidence form is the stronger. Two view points are put forward according to the study results :（1）under fully mechanized caving （fully-mechanized top-coal caving）, depth-thickness ratio can be used as the surface movement boundary between continuity and discontinuity.（2）under fully mechanized caving （fully-mechanized top-coal caving）, when the depth-thickness ratio is less than 40, the surface movement lasting time can be estimated within 1.85 times of mining depth.

Oil shale in-situ heat injection technology is very competitive to exploit oil shale. The deformation of oil shale with heat will affect the migration pathway of thermolysis products and stability of heat-injection well and production well. Utilizing the self-developed high temperature triaxial rock mechanics test system, the law of axial deformation with temperature under the stress condition of 500m was studied.The results indicate that:1)The overall deformation of oil shale is dilated from room temperature(RT) to 600℃.The dilation deformation can be divided into two stages: low temperature expansion from RT to 300 ℃ and high temperature expansion between 300℃ and 600℃. The coefficient of linear thermal expansion in high temperatures is larger than that of the low temperature stage;2) Organic pyrolysis has little impact on thermal deformation of oil shale with less organic matter, but has significant impact on coal rich in organic matter;3) In the process of heat injection to exploit shale oil and gas, the thermal expansion of oil shale layer and roof strata may lead to slight surface uplift, which is different from the surface collapse in traditional mining.

In order to obtain the relation of undisturbed loess’ pore size distribution and mechanical property, with undisturbed loess as the research object to carry out the testing of NMR observation and triaxial shear under repeated freeze-thaw action. The experimental results show that in a freeze-thaw environment loess’ strength and internal pore structure change, with the number of freeze-thaw increasing, soil’s cohesion decreases and tends to stable finally. And its internal friction angle is basically stable, slightly reduced, and the change is between 1°~2°. Repeated freeze-thaw action makes the fine particles of soil increase; In the aspect of pores, the change of small pores’ number is from decreasing to increasing, while the change of middle and large pores’ number is from increasing to decreasing. With the freezing temperature gradually decreasing, the cohesion of soil will increase, however，the internal friction angle of undisturbed soil is basically stable.

Abstract：With the development of science and technology, China's demand for coal has also been increasing. In the process of storage and transportation, it will inevitably produce a lot of dust, not only polluting the environment but also threatening human health. In this study, sodium alginate was used as the grafting matrix. Through the multiple modification of ammonium alginate and the interaction of anionic surfactants, a new environment-friendly dust suppression agent was prepared. Through the study of the relevant properties of dust suppression agent, it was found that the dust suppression agent has excellent performance and good dust suppression effect.

There are certain hazardous areas under the mine that do not allow workers to enter without safety measures, however, due to some environmental or human factors, the commonly used warning signs are not strong enough, resulting in the occurrence of underground accidents.Therefore, an automatic detection method based on computer vision is used to detect whether workers enter dangerous areas. The method first uses a kernel correlation filter algorithm KCF (Kernel Correlation Filter) to track the target,then use the binocular vision principle to measure the tracked target.Simultaneously the Kalman filter algorithm is used to optimize the obtained distance information,which make the ranging method a certain robustness for the occlusion target, and ensure that the target is outside the dangerous area.The downhole target tracking and ranging method has the advantages of low price, low calculation amount, large measuring distance range and high accuracy of ranging.

Coal water slurry (CWS) requires a certain fineness and size distribution of the coal powder to obtain higher packing density. In practice, grinding methods exert an important influence on these parameters. In this study, a ball mill, a rod mill and a planetary mill were used to grind a long flame coal. The particle size distributions and their packing densities with different grinding methods at different grinding time were tested and analyzed through fitting the data by Rosin-Rammler model. The results showed that the grinding efficiency of the ball mill and the planetary mill were much higher than that of the rod mill. Their products were much finer. However, the size distributions were narrower, and their packing densities were much lower than that of the rod mill. The uniformity index of the Rosin-Rammler equation had a well linear relation with the packing density when its values varying 0.75~1.3. Therefore, the uniformity index could be used as a fast evaluation method for the particles packing density.

Coke powder replaces activated carbon as the adsorbent applied in coking wastewater treatment because of the similar properties. Study on modifying coke powder into activated coke and conducting coke powder as adsorbent directly was both introduced. Influence factors of treatment effect concerned by many studies like coke powder dose, coke powder’s grain diameter, adsorption time and coking wastewater pH was evaluated. In addition, the problem of such application in practice was studied. It is indicated that more researches should be attracted on coke powder applied to coking wastewater treatment as its great potential.

In order to achieve high efficiency of flotation of bituminous coal slime, swill-cooked dirty oil, Gemini cationic surfactants (31709 surfactants) were used as main raw materials in synthesis of a new type of highly efficient microemulsion collector (DG-1), test result illustrated that the volume fraction of microemulsion droplets were more than 98% and had good stability. Flotation experiments and cost-benefit estimates demonstrated that the flotation performance and clean-coal profit of DG-1 were all better than 0# diesel when the dosage of collectors was same, the improvement of DG-1 flotation performance was closely related to the adjunction of 31709 surfactants. X-ray photoelectron spectroscopy (XPS)，contact angle meter and microiontophoresis apparatus were used to investigate that 31709 surfactants promote flotation performance of DG-1, the results illustrated that 31709 surfactants efficiently cover oxygen-containing functional groups, inducing the reduction of oxygen content on coal slime surfaces and the enhancement of the hydrophobicity of coal slime; the contact angle of coal slime increased about 12° after adsorbing 31709 surfactants, which further verified the enhancement of hydrophobicity of coal slime after adsorption; meanwhile, 31709 surfactants promoted the dispersal of coal slime and increased the stability of coal slime, which were favorable for the improvement of coal slime flotation.

The coal-flotation test of low-rank coal was carried out.by taking the low-rank coal of a coal preparation plant in Mahuangliang, Inner Mongolia as the research object, using the gravity-purifying coal from a coking coal preparation plant in Shanxi as the carrier material. The industrial analysis and XRD test of low-rank coal are carried out firstly. The results show that the coal samples have high volatile content, and clay minerals in the coal samples mainly contain kaolinite and montmorillonite. Then the low-rank coal flotation test with different particle size carriers and carrier recovery test were performed. The results show that the carrier with 0.5-0.25mm particle size can greatly improve the flotation efficiency of low-rank coal. With the decrease of carrier particle size, flotation effect weakened. Meanwhile, the recovery rate of 0.5-0.25mm granular carrier reached 98.92%. Finally, strengthening mechanism of low rank coal flotation on the carrier were discussed.

In order to solve the problems of long moving time and high safety risk of hydraulic support in fully mechanized mining face, this paper studies a new technology of hydraulic support loading and unloading device and moving group loader in fully mechanized mining face. And the industrial test was carried out on the No. 11105 fully mechanized mining face of Shanxi Youyu Dongwabei coal industry. The test results show that the loading and unloading device t achieves near loading and unloading hydraulic support, has stable performance, improves relocation efficiency, reduces the amount of floating coal work and damage to the bottom plate, improves the working environment, and reduces the labor intensity of the workers. It is safe and reliable to avoid roof caving and rope breaking and has remarkable economic benefit. It has great promotion value and broad market prospect.

According to the limitations of single method in forecasting human resource demand of coal industry, we present a combination forecasting method based on multiple regression model and grey forecasting. By using the data of 30 coal enterprises during the period of 2013-2017 and extracting two main factors: the annual coal output and worker salary level, we forecasted the operation and management human resource demand of coal industry from 2013to 2017. The research result shows that the combination forecasting method is more effective than the single forecasting method, and the combination forecasting method has good applicability.

Based on panel data of China central and western provinces from 2003 to 2016, this paper constructs a VAR model of coal consumption, economic growth and haze pollution to study their dynamic effect. Through using GMM, impulse response function and variance decomposition, we found that the response of haze pollution to coal consumption is negative in the short term and positive in the long term. The response of economic growth to coal consumption is positive in the short term and negative in the long term. Economic growth plays a strong role in explaining coal consumption. Haze pollution is more affected by coal consumption and less affected by economic growth.