In order to improve the mining efficiency of fully-mechanized mining face and accelerate the popularization and application of intelligent mining technology, the key factors affecting the mining efficiency, including cutting speed of shearer, following speed of hydraulic support, conveying capacity of scraper conveyor, collaborative planning of mining path and so on, were analyzed with the target of ten million ton production capacity of 2~3m medium thick coal seam. The development process and advanced cases of key technologies of rapid coal mining at home and abroad are briefly described, including the high efficiency mining technology of about 2m coal seam in Tunnel Ridge mine in America and the 3~4m high efficiency intelligent mining face with a capacity of ten million tons in Zhuanlongwan coal mine in China. The specific research direction and target of localization technology and equipment for fast coal mining with ten million ton capacity in medium thick coal seam are put forward: the length of mining face over 400m; shearer running speed up to 15m/min; 6s following speed of hydraulic support; scraper conveyor speed up to 2m/s and chain dynamic management technology, at the same time strengthen the reliability of equipment and system to ensure that the daily operation time increased to more than 20h.This paper provides a reference for the technology research and engineering construction of rapid coal mining in medium-thick coal seams.

In order to analyze the feasibility of upward mining of close thick coal seam in taohutu coal mine, the theoretical calculation of the protection range formed by the mining of lower 3-1 coal seam is carried out, and the influence degree of 3-1 coal seam mining on the whole of 2-2 coal seam and the mine pressure behavior law are analyzed by using theoretical analysis and similar simulation methods. The research results show that: the initial incoming pressure step of 3-1 coal seam after mining is 45m, the periodic incoming pressure step is 18m, the fracture angle at the cuthole is 62°, the fracture angle at the working face is 61°, the height of collapse zone is 44m, the height of water-conducting fracture zone is 83m; the overall continuity of 2-2 coal seam is good, no step misalignment, the range of mining influence coefficient K is 7.31~9.81, 2-2 coal seam is in the fracture zone of 3-1 coal seam. The 2-2 coal seam is within the fissure zone of 3-1 coal seam, which meets the requirements of anti-procedural mining. The research results provide a theoretical basis for similar mining conditions.

Whether the thin coal seam can be recovered with low cost and high efficiency has always been the focus of open-pit coal mining industry. In China, most of the minimum selective mining thickness for open-pit mining follows the measurement thickness recommended in the Specifications for Coal and Peat Exploration, which is no less than 1. 5m for lignite, and no less than 1. 0m for other coal types. While in Australia, there are many thin coal seams, especially in Hunter Valley, where thin coal seams dominate in most of the coal fields, and the minimum selective mining thickness there is generally 0. 3m. Taking an open-pit mine in Hunter Valley as an example, the rationality of minimum selective mining thickness of thin coal seam in Australia is discussed from multiple perspectives, so as to offer reference for thin coal seam mining in China.

In order to isolate the influx of water from adjacent coal mines, combined with the original waterproof gate wall layout and surrounding rock characteristics of the main coking coal mine, two waterproof gate wall reinforcement construction schemes are proposed, and the stress distribution and displacement deformation of the two waterproof gate walls are analyzed by numerical simulation. Optimized the construction plan from the perspectives of history, construction safety, and cost control, and decided to adopt the plan of strengthening the construction of the new gate wall based on the original gate wall and forming a new whole with the original gate wall. The key points and construction techniques of reinforcement construction are put forward, which avoids the cost of dismantling the original gate wall and the problems of surrounding rock damage. Field application practice shows that the reinforcement effect of the waterproof gate wall is obvious, which effectively isolates the influx of old empty water from adjacent mines, and provides a reference for the waterproof gate wall reinforcement construction under similar conditions.

In view of the problems that the selection and design method and calculation formula of crusher are mainly based on experience, lack of theoretical basis, and the calculation method of production capacity of semi continuous process system is inconsistent with practice. This paper systematically analyzes the key technologies in the type selection design and production capacity calculation of crushing station, such as the type selection parameters and production capacity calculation method of heavy plate feeder, the relationship between the maximum size of material and the diameter of crusher drum, the relationship between material moisture content, operation temperature and equipment technical production capacity, and the determination method of semi continuous process system utilization and effective operation time, The selection and design method of main technical parameters of double toothed roll crusher is improved. Based on the synchronization coefficient, the calculation formula of system utilization is modified, and a method for calculating the production capacity of semi continuous mining process system in line with the actual working conditions is proposed. Taking the semi continuous process system of self moving crushing station in an open-pit mine in Inner Mongolia as an example, the correctness of the results is verified, and ideas and methods are put forward to solve the problems or problems faced in semi continuous process design and practical application.

As the coal quality of raw coal fluctuates sharply in Liangshuijing Coal Mine, the raw coal sizing screen cannot meet the coal quality requirements, and the screening efficiency is low, resulting in imbalanced feeding amount of lump coal and fine coal preparation system, thus the overall coal preparation capacity declines and affects mine production in turn. The original banana screen is transformed into a double-layer screen with an ordinary fixed screen plate on the upper screen surface and a flip-flow screen plate on the lower screen surface. The transformation scheme is studied and demonstrated. The application results show that the screening efficiency of raw coal has been significantly improved after the transformation, while ensuring the screening accuracy of lump coal, thus the workload on the slime water system is reduced and the processing capacity of the coal preparation plant and the normal production of the mine are guaranteed.

This paper analyzes the transportation characteristics of the coal expressway and the factors considered in the route selection to verify the design of an example. Taking the Jining to Hohhot section of the Jingxin expressway as an example, it analyzes the location and terrain climate of the main coal transportation channel And other factors to choose a suitable coal expressway design scheme. Through the comprehensive comparison of economy, technology and rationality, the sunny slope route scheme, hillside route scheme and tunnel layout scheme I are finally selected. In addition, the rationality and safety of the long-and-large downhill design was demonstrated, and feasible road design schemes were proposed to provide a guarantee for the driving safety of the road section.

The lengthening of the working face can effectively improve the mine output, but with the growth of the working face, the mine pressure will appear obvious changes, and the difficulty of supporting the working face and two roadway will increase.In order to reduce the influence of roof pressure on the mining roadway without coal pillar and enhance the stability of the roadway, the synergistic control technology of deep hole pre-splitting pressure relief and reinforced support in the roadway is adopted in this paper to study the mechanism of deep hole blasting and reinforced support in the roadway.Using FLAC and UDEC numerical simulation software, the effect of pressure relief by technical parameters of deep hole pre-splitting and the effect of roadway strengthening support scheme were numericaly analyzed, the best roof pre-splitting scheme and roadway strengthening support scheme were determined, and the industrial experiment was carried out in the tunnel under 2803 working face of Chen fourth floor coal mine.The results show that the optimal plan of deep hole pre-splitting is the pre-splitting distance of 600mm, the pre-splitting height of 17m and the pre-splitting Angle of 15°.Industrial tests measured and analyzed the displacement of 2803 lower tunnel is controlled within 500mm, and the resistance of working face support is between 3000kN and 5000kN. After pressure relief, the roof of working face has little influence on the roadway.

Taking the upward mining of No.1 Coal Seam in Yangchangwan Coal Mine as the research background, the roadway layout and support technology of upward mining of close distance coal seam in thick seam goaf were studied by means of field observation and numerical simulation. According to the deformation and failure of surrounding rock revealed in the actual exploration roadway, the reasonable roadway layout mode for coal up mining is internal staggered arrangement in order to avoid the staggered subsidence zone of the edge steps in the goaf, and the horizontal staggered distance between the roadway of No.1 coal face and the edge of No.2 coal goaf is no less than 20 m. By means of numerical simulation and field test, the application effect of three common roadway cross-section shapes, including rectangular cross-section, semicircle arch cross-section and micro arch cross-section, is compared and analyzed. It is determined that the reasonable cross-section shape of No.1 coal mining roadway is micro arch cross-section, and the combined support form of bolt, wire mesh and shotcrete is adopted. According to the monitoring results of multi-point displacement meter on the roadway surface, the overall deformation of the roadway is very small, and the current support form and support parameters of the roadway meet the needs.

roof cutting and pressure releasing and Gob-side entry retaining(GER) is a key technology to increase the coal recovery rate and reduce the roadway excavation rate of 10000 tons. The effect of roof cutting and pressure releasing is a key factor in determining the success of the GER. Based on the engineering background of 39114 working face in Honglin Coal Mine, this paper discusses the change law of the surrounding rock stress and displacement of roadway with cut roof and uncut roof at the roadway facing the roadway based on theoretical analysis and numerical simulation.The relationship between the vertical stress of the surrounding rock and the distance of the leading working face is revealed.The research results show that after the roof is cut, the surrounding rock of the roadway roof forms a stress relief zone with the advancement of the working face. The stress of the roadway roof and the surrounding rocks of the two sides decreases as a whole, and the displacement of the roof is reduced. This optimizes the surrounding rock stress environment of the roadway and reduced the difficulty of surrounding rock control .

The mining length Ⅵ 15-17-12110 work-plane of Shoushan Coal Mine is 260 meters, the route of conventional cross-measure borehole is not enough and controllable, which result in blanking zone of gas drainage. For this reason, to verify the feasibility of directional composite drilling technology in outburst coal seam, Ⅵ 15-17-12110 work-plane was taken as the test subject, light directional drilling rig was applied for field test. Combining directional drilling with rotary drilling, the blank area in the middle of work-plane where conventional cross-measure borehole cannot control was used directional borehole for regional gas control. The field test result shows that the directional composite drilling technology would control the gas drainage in the mining area of work-plane by means of branch holes along the tendency of coal seam. The total length of boreholes is 580.5 meters, including rock hole section of 344.5 meters and coal hole section of 236.0 meters. The coal of 165.5 tons were flushed out. Through directional cross-measure boreholes, the geological conditions from the roadway to coal seam were proved as follows: the coal thickness was 5.6 meters, the gangue was 0.8 meters, and the distance between gangue and coal seam was 2.8 meters. The test results would provide new ideas and reliable technical support for regional gas control in outburst coal seam.

Aiming at the problems of large quantity and slow construction speed in the construction of water exploration and discharge holes of heading face in the coal mine roadway, a split crawler drilling rig with narrow body, flexible movement and twin boom was developed. It was used in the heading face of E2308 belt gateway in Gaohe Coal Mine. The results show that the drilling rig has reasonable structure design, safety and reliability, short operation assistance time and high drilling efficiency, which provides reference and guidance for similar construction of water exploration and discharge holes of heading face in other coal mine.

In order to reduce the problems of high stress concentration and rock bursts in the hard roof rock of the extra-thick coal seam, the extra-thick hard roof hydraulic fracturing construction technology is adopted, and the hydraulic fracturing technology is used for fracturing at the 401101 working face of Mengcun coal mine in Binchang mining area. Field test, through the theoretical analysis of the fracture hole stress field and comprehensive analysis of various on-site monitoring methods. The results show that the borehole wall is damaged to different degrees at the fracturing position, resulting in three types of cracks: oblique cut, longitudinal and transverse fractures. After fracturing, the rock formations between the holes can penetrate well in the direction of the minimum horizontal stress. The vertical fracturing effect of the old roof is considerable; after the working face enters the hydraulic pre-cracking area, the frequency of high-level energy microseismic events is significantly reduced; after the working face advances to the high-pressure water pre-cracking area, the roof collapses sufficiently in the end range, and the support The peak working resistance and load increase coefficient are generally larger than those in the non-fracturing zone, and the empty load and leakage rate of the bracket are reduced. It shows that roof hydraulic fracturing technology can effectively provide strong technical support for the control of hard roof pressure relief in extra-thick coal seams.

Aiming at the problems of traditional cement slurry such as high bleeding rate, low stone rate, high dispersion of water material and high treatment cost, the high concentration cementing material filling treatment technology was put forward. In this paper, aeolian sand was used as the filling aggregate, and the physical and mechanical properties of high concentration cemented materials, such as strength, setting time, slump, stratification, bleeding rate and setting rate, were tested in laboratory. The material ratio that meets the strength and transportation requirements was selected. Based on the treatment of abandoned small kiln goaf under an industrial square in Northern Shaanxi Province, through drilling, drilling peeping and 3D laser scanning, the occurrence state and coal pillar distribution of goaf were found out, and the volume of cavities and voids in goaf was calculated quantitatively, which provided basis for accurate design of goaf. According to the results of the goaf exploration and the performance of the high-concentration cement material, the filling design and filling treatment were carried out. The three methods of comprehensive drilling core verification, filling solid strength test and site deformation monitoring were demonstrated, indicating that the high-concentration cement material filling reached design requirements for goaf treatment, while reducing the cost of filling materials by 32.5%, providing a new way for low-cost and efficient treatment of hollow voids.

Abstract: In order to effectively control the fire hazard in the goaf of the small kiln and prevent the leakage of fire and harmful gases from damaging the coal working face of the lower coal, the detection method combining the isotope radon method and the up and down borehole detection method is used to delineate the hidden danger area, and take targeted measures. Governance measures such as surface fissure plugging, ground borehole injection of liquid nitrogen, and underground nitrogen injection.The results show that the combination of isotope radon measurement and borehole detection can effectively delineate the range of hidden dangers in a relatively short time;The treatment measures of fissure plugging and joint nitrogen injection above and below the well reduced the temperature of the overlying goaf and the concentration of harmful gases such as CO to below the standard, eliminating fire hazards and ensuring the safe mining conditions of the 13103 fully mechanized caving face.

In order to solve the problem of predicting and forecasting large-area roof cutting and supports crushing disasters caused by high-level separation water inrush from the super thick aquifer in Yonglong mining area, the continuous monitoring of the water level in the aquifer and the real-time monitoring of mine pressure at the working face are adopted, and based on three examples, the paper analyzed linkage effect between water level of the aquifer and the working face rock pressure, and studied reasonable threshold value of warning index of roof cutting and supports crushing disaster in fully mechanized caving face from the major cyclic weighting interval, support working resistance, the dynamic load coefficient, the support resistance increase rate, the safety valve opening rate and the long view hole water level deceleration. Research indicators that the reasonable thresholds of early warning indicators for cut-top and support-supporting disasters in fully mechanized caving face are studied. The research shows that: the water level of aquifers- the major cyclic weighting -water inrush and supports crushing has significant sequence and linkage, and the square position is high-prone area of water inrush and supports crushing. In comparison with normal pressure, the increase rate of supports pressure increased by 305.8% during the major cyclic weighting, and the working resistance, dynamic load coefficient and the opening rate of safety valve all increased in different proportions, besides, the water level deceleration rate of the aquifer also continued to increase. Divided the precursory and real-time warning indicators, and proposed a two-stage warning method and a two-stage warning-prevention mechanism. The correctness and applicability of the warning indicators and methods are verified by field application. The research results have reference value for the early warning and prevention of water hazard and roof cutting and supports crushing disasters such as Yonglong and Binchang mining district in Shanxi.

The control of surrounding rock stability of gob-side entry retaining is a difficult problem that restricts the safe production of coal mine. In view of the present situation of deformation and failure of surrounding rock in gob-side entry retaining at 1226 working face in Shuguang Coal Mine, this paper analyzes that the main problems existing in the original bolt support of gob-side entry retaining, which the roof bolt and anchor cable are arranged in the same row, the pre-stress of bolt and anchor cable is small, and the bearing capacity of the anchor cable flat supporting plate is low and it does not have the function of yield pressure and diffusion prestress. The in-situ stress in the retained roadway area is of medium-level tectonic stress, the influence of the direction of horizontal principal stress on the top and slope angle is considered in the roadway support, the shallow part of coal seam is broken and its strength is low, so it is very important to control the stability of coal side. The paper puts forward and optimizes the bolt supporting technology in the gob-side entry retained in 1228 transport roadway, namely changing the arrangement of roof bolts and cables in the gob-side entry retained to interval arrangement, increasing the support strength of bolts and cables, improving the reasonable matching of bolts and cables and supporting plate, emphasising the vertical installation of anchor bolts, and increasing of the pre-stress level of bolts and cables. Finally, in view of the strong floor heave control in the later stage of roadway retaining, the hydraulic top-cutting method to pressure-relief is suggested.

The failure law and fracture development characteristics of overlying strata in shallow coal seams are closely related to the safe mining of coal mines. In order to study the disturbance failure law of overlying strata and the development characteristics of water diversion fracture zone in shallow coal seam mining, taking 2-2 coal S1233 working face in the south of Ningtiaota mine field as the research object, through similar material simulation and numerical simulation methods, the failure law of overlying rock and the characteristics of fracture development are studied. Similar simulation experiments show that the initial pressure step distance of S1233 face is about 60m, the periodic pressure step distance is about 16m, the height of water diversion fracture zone is 165m, and the crack-mining ratio is 27.5. Numerical simulation experiment shows that the development process of the water-conducting fracture zone can be divided into four stages: gestation, occurrence and slow increase, sudden increase and stability. the water-conducting fracture zone finally develops to the surface, reaching 165m, and the fracture-mining ratio is 27.5.With reference to the measured results of boreholes in the north of Ningtiaota Coal Mine, it is comprehensively determined that the split mining ratio of 2-2 coal in the south wing is more than 27.5.The research results can provide guidance for mine water disaster prevention and water resources protection in shallow coal seam mining.

In order to study the influence of reinforcement depth on the deformation and failure of floor rock for the grouting design, the influence of reinforcement depth on the deformation and failure of floor rock under the condition of near Ordovician limestone confined aquifer and thin aquiclude is studied. According to the geological conditions of the mine, the basic shape of the floor rock under the influence of the weathering zone under the mining action is constructed, and the effect of grouting reinforcement on different strata is analyzed. Then, the numerical model is established for verification. The calculation results show that there are obvious mutation points in the displacement curve of the monitoring points when the top layer of Ordovician limestone is weathered. The displacement curve of the monitoring points is divided into three sections, corresponding to the weathered rock, Ordovician limestone and the upper floor rock of the weathered layer. The maximum displacement of the monitoring point with the reinforcement depth of 14 m is less than the maximum displacement of the rock mass without reinforcement, and the displacement decreases by 6.2%; when the weathered rock mass on the top of Ordovician limestone is reinforced, the maximum displacement is less than the maximum displacement with the reinforcement depth of 14m, and the displacement decreases obviously. The displacement curve of monitoring points can be divided into three sections and two sections with mining length of 250 m; with the increase of reinforcement depth, the three sections change to two sections. Grouting reinforcement plays a good role in resisting the deformation of the floor. To a certain extent, the greater the depth of grouting reinforcement, the better the grouting effect.

Aiming at the problem of poor blasting effect of rock roadway excavation technology, taking the - 648m horizontal cooling chamber of Gubei Coal Mine as the research object, referring to the original scheme of rock roadway section excavation, combined with the field analysis, some key factors affecting the blasting effect (hole depth, cutting form, explosive consumption, etc.) are analyzed. At the same time, on the basis of optimizing the blasting parameters, according to the actual situation of the rock roadway in the coal mine, three blasting schemes with cut hole super depth of 300400500mm are designed. The effect of the three blasting schemes is verified by the field test, and compared with the original scheme. Finally, the optimal super depth of the blast hole, the distribution and layout of the blast hole and the explosive are determined The consumption of relevant data, so as to improve the utilization rate of blasthole, and lay the foundation for saving the cost of tunneling and improving the quality of tunneling.

In order to explore the movement law of overburden in shallow coal seam with different mining face lengths, the 22306 face of Shigetai Coal Mine is studied as the engineering background. The relationship between the mining face lengths and the overburden pressure arch height is studied through theoretical analysis. The plastic failure range of overburden under different mining face lengths is calculated based on numerical simulation. The reasonable mining face length is determined by combining the theoretical analysis and numerical calculation results, and the reliability of the research results is verified with the field industrial test. The results show that the longer the mining face is, the higher the overburden pressure arch height is. When the buried depth of the mining face is less than twice the pressure arch height, a stable pressure arch cannot be formed in the overburden. The plastic failure range of overburden is positively correlated with the length of mining face, but when the length of mining face increases to a certain range, the development speed of plastic zone is gentle. The results of on-site hydraulic support working resistance monitoring and tunnel surrounding rock deformation observation show that the length of 290m mining face can fully ensure the safe mining of 22306 mining face.

Coal spontaneous combustion is one of the main disasters in mine, which will cause many problems such as energy waste. Coal fired power plants are the main source of CO2 concentrated emission. The content of inert gas in flue gas of power plant is over 80%, and the content of oxygen is below 10%. Injecting flue gas of power plant into underground goaf can not only seal CO2 and other gases, but also prevent spontaneous combustion of coal left in goaf. Firstly, the feasibility of injecting flue gas of power plant into goaf to prevent spontaneous combustion of residual coal is summarized from the aspects of low oxygen concentration and coal adsorption. Secondly, the advantages and technical route of sealing goaf by flue gas of power plant are expounded. Finally, the development of fire prevention and extinguishing technology by injecting flue gas of power plant into goaf is prospected. It is considered that it is feasible and promising to seal goaf with flue gas of power plant, but gas monitoring and leakage prevention still need to be improved. Future research focuses on the long-distance transportation and storage of flue gas. This technology is expected to help China achieve the goal of carbon peak in 2030 and carbon neutrality in 2060 early.

In order to evaluate risk of coal spontaneous combustion more reasonably, a multi-index evaluation system is proposed . According to the principle of minimum information discrimination, combining the advantages of both qualitative and quantitative weighting methods, a combined weighting determination method is proposed, and an evaluation model is constructed based on TOPSIS. The method is adopted to appraise fifteen samples in different coal mines. The results of the evaluation a consistent of the investigation. The results help to scientifically evaluate the characteristics of coal spontaneous combustion from different coal faces, as well as optimize the program of spontaneous combustion prevention for managers.

Based on one-dimensional unsteady flow differential equation, a dynamic dispersion migration model of instantaneous harmful gas in mine air network is established to realize the rapid prediction of instantaneous harmful gas concentration in complex mine pipe network. The variation law of harmful gas cloud group at roadway intersection is analyzed. The accuracy of tracer gas model is verified by using large-scale experimental roadway model. The results show that the propagation law of the instantaneous release of harmful gases in the roadway conforms to the Gaussian distribution model However, the maximum error between the peak SF6 concentration and the simulated peak is 9.56 and the maximum error of the predicted peak arrival time is 3.88. Therefore, the migration characteristics of harmful gas cloud in complex pipe network can be predicted only by considering the action of gas translation and dispersion with flow, and the research results provide technical support for the formulation of mine air control measures.

In order to realize the intelligent mining of the fully mechanized excavation face, in response to the need for real-time accurate measurement of the roadheader's position and attitude at work, a combined measurement method for the roadheader's position and attitude based on strapdown inertial navigation and cylinder displacement is proposed. The method uses strapdown inertial navigation to measure the attitude information of the roadheader in real time, combines the displacement data of the cylinder moving the roadheader forward with the attitude information of the roadheader to calculate dead-reckoning, and uses the standard Kalman filter algorithm to combine the strapdown inertial navigation data and the cylinder data Perform fusion to suppress the divergence of inertial navigation measurement results and improve the accuracy of pose measurement. The results of downhole experiments show that the pitch angle, roll angle and heading angle measured by the combination of inertial navigation and the cylinder are0.018596 deg ,0.004635 deg,0.011898 deg and when the intelligent tunneling robot is stationary for 1 hour; In the process, the position error calculated by the combined measurement system is less than 3.5cm and 2cm in the x-axis and y-axis directions, respectively, which overcomes the problem of cumulative errors caused by the pure inertial navigation solution.

Coal flow monitoring in the main coal transportation system of coal mines is an important part of the intelligent transportation of coal mines, which can realize energy saving and consumption reduction in the transportation system, and improve the efficiency and safety of coal transportation in mines. This paper proposes a coal flow measurement method for conveyor belts that combines laser scanning and machine vision. Compared with traditional contact measurement, it can quickly and accurately obtain the full cross-sectional profile information of coal flow. The geometrical mapping relationship between pixel points in the image plane and the corresponding points in the physical space is studied. The conversion coefficient of the image system is obtained through camera calibration experiments, and the definition of the captured image is improved by means of digital image filtering and enhancement. The image segmentation algorithm is used to adjust the laser spot The effective area of the fringe is segmented, and the breakpoint in the laser spot image is repaired by the image expansion operation algorithm, and then the edge skeleton contour of the spot area is fitted, and the center line of the laser spot fringe is calculated and extracted. The Riemann sum method is used to calculate the deformed contour area of the laser spot on the surface of the coal flow in each image, and the cross-sectional area of the coal flow above the belt conveyor is reversed according to the projection angle of the laser in the experimental system, and finally combined with the belt conveyor speed and the image acquisition frame rate Calculation of other parameters to obtain coal flow information.

Aiming at the problem of uneven heating in vulcanizing machine heated by silicon rubber heating sheet，A scheme of replacing single channel layout with three-channel return layout is proposed.First A three-level and five-factor orthogonal test is designed for the parameters of heating spacing and power.Based on Comsol solid heat transfer simulation technology, the temperature distribution law of each scheme heating plate is simulated and the range analysis is carried out.Then best design scheme is obtained. Sometimes the physical test is verified and studyFinally it is found that the most significant factor affecting the uniformity of the heating plate is the edge heat flux.With the original single-channel heating method, the temperature difference on the heating plate surface of the optimal scheme was reduced from 12℃ to 3.8℃ and the uniformity index F value is reduced by 1.3. It effectively prove the effectiveness of the design scheme and provide research methods and ideas for actual production.

In coal blending optimization, due to the lag of the calculation of power supply coal consumption, the power supply coal consumption of the blended coal can not be obtained, so usually the lowest price of blended coal can only be taken as the objective function ,but this does not guarantee the cost reduction and efficiency increase of power plant. Therefore, this paper uses the digital twin model of a 320 MW power plant based on Thermoflow to simulate the power plant burning different kinds of coal, establishes the database of coal quality and power supply coal consumption, and BP neural network is applied to establish the relationship model of coal quality and power supply coal consumption. On this basis, taking the coal quality index as the constraint condition, combined with the blended coal price and transportation expenses, and taking the lowest power supply coal consumption cost as the objective function, the coal blending optimization model is established. According to the actual demand of the power plant, the optimal blending scheme is given. The model can help the power plant quickly obtain the power supply cost of burning the coal or blending the coal, and provide guidance for the coal source selection and blending optimization of the power plant.

In the process of flocculation and sedimentation of slime water, there are many influencing factors. This paper mainly studies the influence of GT value on flocculation and sedimentation effect under different concentrations of slime water. The results show that the dosage of coal slurry is different when the concentration of coal slurry is different. For a certain concentration of slime water, with the change of GT value, the flocculation and sedimentation effect also shows obvious difference. GT value should not be too high, otherwise the formation process of floc will be destroyed. For this test object, the best GT value should be around 3700.

In order to solve the disadvantages of manual inspection of belt conveyor in coal mine, a belt conveyor inspection robot system is developed, which can realize all-round dynamic inspection and fault identification of belt conveyor and its operating environment in coal mine, and reduce the accident rate. The composition, principle and function of the system are introduced in detail. Through typical examples, the inspection effect of inspection robot is summarized and analyzed. The application results show that the inspection robot system is suitable for belt conveyor inspection under long-distance and complex working conditions, and it is of great significance to realize intelligent construction of coal mines.

At present, the transportation and deployment of anchor nets in permanent support operations of coal mine roadways mainly rely on workers' operations to complete, and there are problems such as low work efficiency, high labor intensity, and high risk factors. On the basis of the coal mine intelligent tunneling robot system developed by the team, an anchor net transportation robot system that automatically fetches, transports and arranges the net is proposed. Research and design the mechanical structure of the anchor-net transport robot, use Solidworks to establish a three-dimensional model, and conduct mechanical analysis on the structure of the net-taking manipulator; establish a system operation mechanism, build a kinematic model of the manipulator based on the DH method, and analyze its workspace. Fifth degree polynomial interpolation to solve the end motion trajectory. The results show that the anchor net transport robot has a reasonable structure design, strong reliability, high stability, and high transportation and deployment efficiency.

Abstract:Aiming at the problems of complex geological conditions, limited space, low automation degree of driving and anchoring equipment and low driving efficiency in coal mine roadway driving face, a new crawler gantry drilling and anchoring robot is proposed, and its reliability is analyzed. The 3D model is built by SolidWorks, and the key parts are analyzed and calculated by ANSYS; The vibration characteristics of gantry type anchor drilling robot are deeply studied, and the first six natural frequencies are obtained, and the vibration modes are analyzed. The results show that the overall structure design of gantry drilling and anchoring robot is reasonable, the stiffness and strength meet the requirements, and it has strong stability and reliability.

With the rapid development of the big data, coal mining enterprises to accumulate a large amount of coal mine data resources. Among them, the coal mine accident case information is rich, including the analysis and summary of the time of the accident, the course of the accident, the cause of the accident, and the accident report. However, it is difficult to extract unstructured data information, and the implicit semantic features cannot be effectively obtained. Therefore, this paper focuses on coal mine accident cases and compares the text representation and classification methods based on Fasttext network, to better mine the semantic information in the text, and then accurately and effectively predict the category of the case accident. Provide strong technical support for the subsequent establishment of expert knowledge base and construction of emergency rescue platform. All the code for the experiment in this paper has been placed on GitHub.