When cross measure dark inclined roadway pass through the mining face that is being worked above, it is necessary to rationally locate coal pillars and the stopping line so as to reduce the resource loss under the premise of protecting the safety and stability of the cross measure inclined roadway. This paper theoretically analyzes the stress distribution of surrounding rock and damage state of the floor during the extraction of the upper coal seam against 4102 long-wall panel of Shanxi Shenzhou Coal Mine. Based on the calculation results, the optimization is proposed. Compared with the layout of original working surface, the extension arrangement of the inclined shaft is determined when the 4102 long-wall face is in above. This can recover about 22,000 more tons of high quality main coking coal, which has considerable economic benefits for mines entering the resource depletion phase.

BIM Technology has been widely used in water conservancy, hydropower, metallurgy and other industries recently, but it is relatively backward in coal industry, especially in mining design. Based on the secondary development of the software and the experience of other engineering industries, this project completed the main contents of the BIM design of mining engineering in Zhangjiamao coal mine, and verified the feasibility of using BIM Technology in mine design, especially in mining engineering design. The paper also analyzes the existing problems of adopting BIM Technology in mining engineering, and points out the development direction of BIM Technology in mining engineering industry。

To from an efficient coal transport system, we proposed two methods of coal transport taken into account the roadway layout and surrounding strata condition of Shunhe Mine. Comparisons between the two methods indicated that using the vertical bin for the coal transfer was better than using conveyor. Considering the combined use of rail and belt transport system at the top of bin and the belt conveyor at the bottom of the bin, we proposed using “I-beam + steel rail + steel plate” to form an interlocking support pattern so as to ensure the strength at the bin opening. At the bin bottom where there was a loading chamber, an integrated support patterns using “cable + I-beam + anchoring and shotcreting” was adopted, meanwhile, one-piece precast casting support was used as well. Field application demonstrated the bin had guaranteed the efficient transport of coal from the panel, the design of the bin and its support system could provide reference for bin construction with similar condition.

Taking Kailuan Group Donghuantuo Coal Preparation Plant as an example, the feasibility of combining five coal seams into two coal seams for coal quality analysis was demonstrated from three aspects of proximate analysis indicator, size consist and densimetric consist through comparative analysis of a large amount of data. In terms of proximate analysis indicator, coal, ash, sulfur and calorific value were compared. The coal seam occurrence conditions and mining methods are compared in terms of size consist. The density levels of elemental ash and floating ash were compared with each other in terms of densimetric cosist.

Abstract: In order to explain the performance characteristics and application status of the two types of flip-flow screens in China. the structure and working principle of two kinds of flip-flow screens are introduced, the installation methods of two kinds of sieve plates are compared, according to the practical application of two kinds of screens in coal preparation plants in China, the performance parameters of the two kinds of screens are analyzed from the point of view of dynamic load and power efficiency and compares the performance parameters between these. The results show that the mechanical flip-flow screen has high stability but consumes a large amount of energy. In the same screen area, it has a higher installation height. The unit power consumption of the vibrating flip-flow screen is lower, but the area efficiency and volumetric efficiency are higher than those of the mechanical type. In addition, compared with other screening machines, the vibration strength of both flip-flow screens and the dynamic load have obvious advantages. This provides a certain reference basis for the majority of users in the selection and use of flip-flow screens.

In order to study influences of changing supporting conditions and the basic stiffness or not on the structural responses, different finite element models were established to simulate the behaviors of coal shed skeleton structure. The structural parameters including natural vibration periods, modes, support reaction forces, member inner forces, and displacements were analyzed and compared. It was shown that the basic stiffness has a greater impact on the structural mechanical properties when using the three-limb floor support. Meanwhile, when selecting the two-limb floor support form, there are few significant differences observed among the force characteristics with different supporting conditions. Simultaneously, the basic stiffness effects slightly on the characteristics. Furthermore, it is recommended to use hinges as the boundary condition. hinges are recommended as the boundary condition.

In order to solve the problem of water disaster prevention and control, tunnel support during tunnel excavation under the water-abandence and weak cementation aquifer, long distance directional drilling technology was used to prospect the water yield property and drainage the water from aquifer. For the area with thin aquiclude, drilling and anchor bolt grouting was used to the roof aquifer reinforcement and reconstuction. For the area that tunnel roof is broken, U-shape steel shed was used to strengthen tunnel support. Though the practiceal verification, the water flow have significantly reduced after the comprehensive prevention and control technology for tunnel excavation, and the water disaster and roof accident were avoided. The prospecting and drainage of tunnel water filling source with long distance directional drilling, water-conductive channel sealing with drilling and anchor bolt grouting, cooperate with U-shape steel shed and tunnel support with U-shape steel shed can be ensure the safety of tunnel excavation under the complex hydrogeological condition.

The deformation and destroying of soft rock roadway was serious in repeated cross mining. In order to solve the support difficult problem of this condition, taking Ⅱ82 transport rise of Luling coal mine as the engineering background, we summarized distortion and failure character of roadway. Through strength experiment of rock mechanics, field borehole observation and theoretical analysis, main reason for roadway of losing stability was studied. It were low strength of surrounding rock, unreasonable choice of support method and repeated cross mining influence. Finally, the control technology of "conventional anchor net spray + shallow surrounding rock grouting reinforcement + mine high-strength anchor cable bundle combined with hollow grouting anchor cable support" was proposed. Field practice showed that the total displacement of roof, floor and sides of roadway in the test section was 20mm, 42mm and 25mm respectively during the cross mining of the working face. It was 43%, 60%, 57% lower than the conventional support roadway in the non-test section, the stability control of the surrounding rock of the roadway was realized.

In order to solve the problem of large-scale sinking of the roof after the tunneling of the 4301 working face of Huaye Coal Mine, the deformation characteristics of the roadway instability were studied by field investigation, theoretical analysis and numerical simulation. The surrounding under different support schemes were analyzed. Rock yield strength, vertical stress and vertical displacement of the roof. The results show that the shed-type supporting structure has effective surrounding rock bearing capacity for the roof, and the "11# I-beam + single hydraulic prop" steel with the spacing of 2m is determined based on the high-strength prestressed anchor support. Shed active support scheme. The engineering test confirmed that the scheme has a good effect, effectively controlled the surrounding rock deformation, solved the problem of roof subsidence, saved production investment and improved the economic benefits of the enterprise.

The anchorage structure and force characteristics of small aperture resin anchorage cable in coal mine are analyzed. The anchorage force lower than its breaking force caused by the unreasonable anchorage structure about tension concentration type anchor cable is one of important reasons why it is difficult to control the deformation of rock surrounding in deep roadway, and this objective fact was pointed out. The anchor structure is comprehensive analyzed, one is anchor cable by tension concentration type for mining, another is anchor cable by tension dispersion type which commonly used in geotechnical engineering. The resin anchorage agent with slow condensation is developed which gel time 6 ~ 8h and pressure strength 60 MPa or more. On that basis ,the structure and construction technology of a new type of small aperture tensile dispersion anchor cable for mining are presented. Under the construction technology of anchor cable used for mining unchanged condition, time-division anchoring of resin coil with different anchorage sections in the same hole is realized. The anchor section shear stress of the anchor cable is dispersed to two places, and stress concentration in anchorage section is reduced. The application results of multi-pair mine engineering show that this technique can greatly improve anchor reliability and strength utilization of anchor cable. The matching performance of anchorage and breakage in anchor cables are improved, and the control effect of roadway deformation is enhanced significantly.

The 3F 113 working face of Tengdong Shengjian Coal Mine in Shandong Province is affected by many factors, such as goaf, fault, coal pillar and mining, etc. It has strong impact risk. In order to grasp the distribution characteristics of stress anomaly in the working face, the vibration wave CT is proposed. The detection technology, combined with the static evaluation results before mining, carry out the risk analysis of the impact pressure and targeted prevention measures. After detection and analysis, three potential impact zones of A, B and C and six possible uncovered faults were obtained. Before the mining, special measures such as large diameter drilling, blasting pressure relief and bottoming were taken for the potential impact danger zone. The micro-seismic and stress monitoring methods were used to test the pressure relief effect, and finally the safe mining of the dangerous working face with strong impact was realized. The technical system can provide a good reference for the impact hazardous working face under similar conditions.

In order to realize the division of the impact danger zone of steeply-inclined and extremely-thick coal seam in the south mining area of Wudong Coal Mine, the influencing factors of rockburst were determined by comprehensive means such as the in-situ stress tests and the physico-mechanical experiments of coal and rock etc. The intrinsic relationship between different microseismic levels during the mining of upper strata and impact hazard areas was established. At the same time, based on the principle of similarity between the upper and lower strata, the impact zone of the +450 horizontal No. B3+6 fully mechanized top-coal caving face was divided. The results show that the impact hazard areas of the upper and lower layers of the same coal seam in steeply-inclined and extremely-thick coal seam are similar and repeatable if they are mined at the same time. The research results have certain guiding significance for the division of impact hazard zones in the steeply-inclined coal seam.

In order to develop a more safe and reliable technology of roadway repair, In view of the phenomenon that coal mine roadway bottom ripping may influence the stability of the roadway roof and two sides. The similar material simulation test and engineering project analysis was carried out to research the influence of roadway bottom ripping for the stability of sides and roof. The analysis results show that：The roadway floor, roof and two sides are an interactive whole. Roadway bottom ripping will cause the stress distribution characteristics in roadway floor, induce the load-bearing ring move to the deep that can cause tunnel breakage depth increases in both sides and roof, it’s not conducive to the overall stability of the roadway. Then with the conclusion of the research, this article put forward the general principles of roadway bottom ripping: reinforcing roof and two sides before roadway bottom ripping. Roadway repair should mainly clean up the rock mass within the load-bearing ring. Try not to touch the load-bearing ring, Reserved corner or do circular arc transition are beneficial to the overall stability of the roadway when roadway bottom ripping.

In the sealed space of underground coal mine, it has the characteristics of low illumination, high gas concentration and high smoke and dust content. Combining with the complex working environment and the needs of daily monitoring in underground coal mine, the intrinsic safety type of mine intrinsic safety type black light camera has been developed by studying night vision technology, photoelectric conversion technology, intrinsic safety technology and precise testing technology of mine intrinsic safety type black light camera. Laboratory and underground field tests show that the black-and-white minimum illumination of the intrinsically safe black-light camera can reach 0.0001 Lux, the horizontal clarity is 1100 TVL, and the gray scale is 11. Under the condition of low illumination and large coal dust, the real-time video picture can be clearly monitored and transmitted, which has the functions of eliminating hidden dangers of underground safety, monitoring daily work and underground rescue

Mine gas emission prediction of coal mine safety production is very important work, In view of the advantages of principal component analysis and stepwise regression analysis, this paper combines two methods to establish a gas emission generation regression prediction model. Taking the No. 30 coal seam of Junde Coal Mine as an example, four principal component factors affecting the gas emission from the mining face were obtained by principal component analysis, and the stepwise linear regression analysis was used to predict the gas emission from the mining face. The results show that the principal component-stepwise regression analysis reduces the number of variables that need to be considered in the regression analysis. The prediction results have better accuracy, and the prediction accuracy is better than the one-way regression prediction and multiple regression prediction. It has a good application prospect.

In order to study the influence of borehole layout on gas extraction efficiency, using the self-developed multi-field coupled physical simulation test system for coalbed methane production, the physical simulation test of gas extraction under different borehole spacing conditions was carried out, and the influence of borehole spacing on gas extraction effect was discussed. The results show that in the early stage of gas extraction, the rate and quantity of gas pressure drop at each measuring point are mainly affected by the distance from the borehole center, which is basically independent of the distance between the measuring point and the borehole outlet. In the process of gas extraction, the gas pressure gradient near the borehole center was large, the gas flow velocity was large, and middle pressure line of cross-section gas pressure field was circular distribution centered on boreholes. The superposition effect of extraction between adjacent boreholes will affect the effective extraction range. The closer the distance between boreholes, the larger the effective extraction range. At the same time, the effective extraction range also increases exponentially with the extraction time.

Air leakage control in goaf of U+L working face has always been one of the important topics of mine fire prevention and control. In order to study this problem, adiabatic oxidation temperature rise test, field monitoring and numerical simulation were adopted. Based on the determination of characteristic parameters of coal spontaneous combustion limit, the distribution law of "three zones" in goaf was studied by taking an actual mine in Shaanxi Province as an example, and further revealed. Characteristics and danger of spontaneous combustion in goaf. It is found that the lower limit oxygen concentration of spontaneous combustion of coal in the goaf is 12.9%. U+L ventilation mode has a serious impact on the division of "three zones" in the goaf. The fluctuation of "three zones" in the goaf on the intake side will occur due to the influence of air leakage in the auxiliary haulage roadway. The numerical simulation can more intuitively reflect the distribution characteristics of the dangerous zones. The research results have certain guidance and reference significance for mine fire prevention in the same kind of working face.

In order to improve the efficiency of gas drainage, a numerical model of gas drainage by buried pipe in goaf was established, taking the 5877y face of Linnan Cang as the research object. On the premise of keeping other parameters unchanged, COMSOL software is used to simulate the influence of different negative pressure on temperature field, oxygen concentration field and flow field in goaf. The results show that with the increase of suction negative pressure, the high temperature area of the goaf gradually diffuses to the side of the return air lane. The wind leakage flow is transferred from the area near the return wind lane to the end of the buried pipe and the leakage velocity increases. The width of the self-ignition belt on the air inlet side gradually increases, and the air return side decreases firstly and then decreases. The accuracy of the simulation is verified by comparing the simulation results with the field data.

In recent years, mine water damage accidents have become more frequent. In order to reduce the harm caused by mine water inrush accident to coal mine production and human life and property safety, how to judge mine water Inrush source quickly and accurately is more and more important. Aiming at the above problems, a rapid identification method of mine water inrush source coupled with PCA-ELM model is proposed, and validates the method with the water source data of Zhaogezhuang mine as an example. Firstly, the principal component analysis method is used to reduce the dimension of the multi-dimensional variable data, and then the ELM algorithm is used to simulate the selected principal component. The results show that the method has stable classification performance and short classification learning time, which satisfies the condition of rapid identification of water inrush source.

In order to provide a stable and accurate experimental platform for the flaw detection testing of wire ropes and obtain reliable data.In this paper, ADAMS kinematics analysis module is used, a variety of methods for horizontal comparison of schemes are adopted,each schemes was analyzed and compared in terms of speed, force and torque,and the laboratory experimental data was collected and compared.The results show:The design proposed in this paper can provide a stable and reliable working environment, It can simulate a variety of actual working conditions of wire rope, the experimental data obtained in the final experiment is accurate and clear, the difference between the damage segment waveform and the healthy segment waveform is obvious,and meet the requirements of the experimental requirements.

The effective treatment of pollutants in the mine water by the fallen rock in the goaf has important practical significance for evaluating the underground reservoir technology, improving the comprehensive utilization of mine water and comprehensive utilization of coal gangue. In this paper, three underground water reservoirs in Daliuta Coal Mine in Shendong Mining Area are taken as research objects, and three influent samples, four effluent samples and one fissure water samples are collected, focusing on organic matter and heavy metals in different occurrence states. The removal of pollutants from water bodies in the underground reservoir of Daliuta Coal Mine is analyzed. The results show that the clay mineral content in the goaf of the underground reservoir of Daliuta Coal Mine accounts for about 35% of the clay mineral content and has a strong adsorption capacity. The underground water storage system of Daliuta Coal Mine has better purification effect on mine water. The suspended solids content of the effluent is lower than 182mg/L, and the removal rate can reach 80%~93%. A large amount of suspended solids can be removed. The effluent COD content is less than 35mg/L, the removal rate can reach 38%~61%, partial COD can be removed. Analysis shows that the particulate organic matter can be removed with the sedimentation of suspended particles, and the soluble organic matter can be removed by the adsorption of clay minerals. Data display that 99% of Fe and 84% of Mn in the influent are present on suspended particulate matter. After treatment in the groundwater reservoir, the removal rate of Fe in the mine water can reach 68%~100%, and the removal rate of Mn can reach 75%~99%, indicating that the groundwater reservoir can play a certain role in removing heavy metals from suspended particulate matter.

In view of the sealing problem of solid waste filling in mine goaf, the following conclusions are drawn through theoretical analysis, field investigation and other methods: (1) To determine the sealing target of solid waste deep well: solid waste deep geological disposal achieves a stable state, and the target of effective sealing period is set as 20 years (reference standard); (2) To put forward a multi-level sealing technology system for solid waste mine filling, which includes regional sealing, surface sealing and filling. (3) Complete high-strength hard rock or expansive soft rock is the ideal surrounding rock for regional sealing; (4) Design a channel sealing structure suitable for solid waste mine filling, which has two functions of support and sealing; (5) To design a multi-level closed technology system for filling solid waste mines in a coal mine.

To solve the problem of excessive force and serious wear which impact on components of the transfer chute,the structural design parameters affecting the transshipment are obtained by using the trajectory and energy conversion relationship when the coal material is discharged.Using the discrete element analysis EDEM software , to simulate discharge status of the coal material in the linear transfer chute under the different discharge conveyor belts and the angle of the transfer chute.The results show that under the same working conditions, when the belt speed is lower than the rated maximum belt speed by about 25%, the average force value of the coal material to the funnel is the smallest and the force duration is the shortest. When the belt speed is higher than the rated maximum belt speed, The average force value of the funnel increases obviously; when the dip angle of the transfer chute is larger, the average force value of the coal material to the receiving conveyor belt is larger and the duration of the force is longer, and the conveyor belt has a deviation. The problem of missing material is more obvious.The conclusion will provide a reasonable basis and data support for the green development of mining equipment.

Abstract: In this paper, acrylamide (AM) is used as molecular skeleton, acrylamide ethyl three methyl ammonium chloride (DAC) and dimethyl methacrylate (DMAEMA) are cationic monomers, and a new type of organic polymer material is synthesized by aqueous solution polymerization Cationic flocculant PADD. And determine the optimum reaction conditions for its synthesis: pH=3, polymerization temperature of 30 ℃, reaction monomer mass fraction 25%, initiator sodium sulfate (Na2S4O8) and sodium sulfite (Na2SO3) quality fraction of 0.1%, The dosage ratio of medicament monomer was 40:30:30, and the polymerization time was 6h. Afterwards, the viscosity of the product was determined by viscosity method and the relative molecular mass of the product was calculated, the polymer structure was analyzed and characterized by infrared spectroscopy, and the flocculation and sedimentation of coal slurry in preparation plant was studied by using synthetic flocculant.

In order to solve the problem of low automation and intelligent mining of thin coal seams, this paper proposes a thin coal seam hydraulic support electro-hydraulic control system based on dual CAN bus with the idea of “concentrated remote automation control + manual intervention”. By analyzing the coal mining technology of thin coal seam and the key technical indicators of automation and intelligent mining, the overall structure of the system is constructed, and the hardware structure and communication scheme of the system are designed. The function of adjacent bracket control and remote control communication of hydraulic support is verified by experiments. The system has high real-time and stability.

in order to solve the problems of backward automation level, low production efficiency, inaccurate data collection and real-time monitoring of traditional shearer memory coal cutting technology, a shearer monitoring system based on memory coal cutting method was designed. This monitoring system takes PLC s7-300 as the control core and carries out real-time monitoring of parameters of each part of the shearer fuselage. On the one hand, it can effectively improve the precision of coal cutting in memory of the shearer and realize the automatic coal cutting in the triangle area, And then improve the working efficiency and automation level of memory coal cutting, in addition to effectively reduce the failure rate of coal mining machine. The system is composed of shearer memory cutting system, shearer monitoring system and upper machine interface, and the specific design scheme is given.

Aiming at the problem of pressure fluctuation caused when overwinding hydraulic cylinder absorbs the overwinding impact of hoist skip, the optimal design of overwinding hydraulic buffer system of hoist was carried out by adding throttle valve and connecting rod chamber and rodless chamber of overwinding hydraulic cylinder. The working principle of the optimized overwinding hydraulic buffer system of hoist was studied, and the simulation models of overwinding hydraulic buffer system were built based on AMESIM. The dynamic performance curves of pressure on rod chamber, skip displacement and skip speed of overwinding hydraulic cylinder before and after optimization were compared and analyzed. The influence of throttle valve diameter on overwinding hydraulic buffer system was simulated and studied. The research results show that the buffer performance of optimized overwinding hydraulic buffer system is improved, and the throttle valve can absorb the pressure fluctuation on rod chamber of overwinding hydraulic cylinder. The diameter of throttle valve has great influence on the piston reset of overwinding hydraulic cylinder. When the diameter valve is 9 mm, the buffer performance of overwinding hydraulic buffer system is better and the overwinding device has better dynamic characteristics.

In order to study the characteristics of coal mine accidents in Inner Mongolia, and find the internal correlation and occurrence regularity of accidents, we use data of Inner Mongolia coal mine accident and death toll in 2011-2018 from Safety Monthly Report and Incident Investigation Report. Through them to get the characteristics and regularities of coal mine accidents in the whole region. The causes of accidents are further analyzed and countermeasures are put forward. Furthermore, we use model of multiple linear regression analysis to get the quantitative relationship between total number of accidents and different types of accidents. Hoping to provide a scientific basis for defining the trend of coal mine accidents in Inner Mongolia and formulating targeted accident prevention and control measures.

In order to strengthen the risk identification of coal mine hazards and realize the early warning management of safety production in coal mine enterprises，the risk factors of coal mine safety are analyzed，the risk early warning index system is constructed from four aspects of personnel，technology，environment and management，and the risk early warning evaluation model is established based on the basic theory of extension theory. Entropy weight method is used to determine the weight of each early warning index，which avoids the subjectivity of traditional experience，and the quantitative calculation of correlation function is carried out by using MATLAB software. Taking L Coal Mine in Qianxi County of Guizhou Province as an example for engineering application，the comprehensive safety risk warning level of this coal mine is II，corresponding to the "low warning" state，and its risk degree is weak，which is consistent with the actual situation. The overall risk level of the coal mine enterprise is acceptable，but further optimization is needed. The research shows that the theory and method can provide reference for coal mine safety risk early warning and evaluation.