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Table of Content

    15 July 2021, Volume 50 Issue 07
    Previous Issue   
    Intelligent Spectrum Sensing Technology and Research Progress of Rock and Ore in Intelligent Mine
    LIU Shanjun WANG Dong MAO Yachun SONG Liang DING Ruibo LIU Haiqi
    2021, 50(07):  1-15. 
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    With the rise of big data， cloud computing， artificial intelligence and other advanced technologies in the new era， China's mines are gradually stepping forward from the past mechanization and digital development stage to the intelligent stage， and intelligent mines or smart mines emerge as the times require. Due to the defects of heavy workload， low efficiency and long cycle， the traditional rock and ore testing method has become the bottleneck of intelligent mine construction. The development of new rock and ore testing technology has become an important way of modern intelligent mine construction. Therefore， based on the analysis of the current situation and existing problems of rock and mineral testing technology， this paper puts forward the rock and ore intelligent sensing technology based on spectral analysis， referred to as rock and ore spectral intelligent sensing technology. The technology has the characteristics of in-situ testing， non-contact， short cycle， simple process， high efficiency and intelligence， and can identify the composition and content of different minerals in ore and rock. Combined with the research practice of the research group， this paper analyzes the current development status of this technology， and points out that strengthening the construction of rock and ore spectrum database， improving and developing the existing spectrum analysis algorithms， and improving the level of spectral theory research， so as to improve the identification accuracy of rock and ore， will be the main direction of future scientific research work. Meanwhile，the key to the implementation of this technology is to strengthen the research of software and hardware integration and application.
    Treatment Technology， Environmental Evaluation and the Corresponding Management Policies of Aluminum Ash
    SHEN Lingfeng WANG Li XU Rui Lü Fei
    2021, 50(07):  16-26. 
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    Aluminum ash is a toxic and harmful solid waste produced in the production process of aluminum industry. On the one hand， it contains a large amount of metal aluminum and aluminum compounds， which has high industrial recovery and reuse value. On the other hand， it often contains heavy metals such as Cr， Cd， Pb and harmful ions such as F-， Cl-， CN-， which not only can pollute the soil， but also causes groundwater pollution with the migration of heavy metals and harmful ions. It is urgent to seek economic and green aluminum ash recovery methods， appropriate environmental assessment methods and both reasonable and feasible management policies with the further increase of aluminum ash output in China in 2020. The treatment methods， difficulties and future development direction of aluminum ash in China were summarized on three aspects，including treatment methods， environmental evaluation and management policies of aluminum ash. The treatment methods of aluminum ash are mainly divided into aluminum ash recovery， harmless treatment and resource utilization， among which aluminum ash recovery is divided into fire recovery and wet recovery currently. Among them， the salt-free recovery method of roasting method has a great application space in the future due to less pollution and higher recovery rate. The resource utilization of aluminum ash regards aluminum ash as the main raw material to obtain building materials and reagent. Because of the low cost of materials， superior performance and less pollution to the environment， it has a broad application market and development prospect.The environmental evaluation method is based on the Soil Environment （Trial） Evaluation Standard （HJ 964—2018） and Groundwater Environment Evaluation Standard （HJ 610—2016）， and combines various statistical methods to give the evaluation conclusions including the trend of environmental change and the upper limit of bearing capacity， which is a scientific evaluation method with practical significance. Moreover， the hazard of aluminum ash and current management policy of stocking aluminum ash are introduced based on the national laws， local policies and some enterprise policies， which can provide reference for future policy formulation of enterprises. In a word， it is not difficult to see through the combination of aluminum ash treatment， environmental evaluation and management policy， scientific research and production will combine with each other closely to promote the aluminum ash treatment method towards the gradual green non-toxic and comprehensive utilization direction.
    Non-explosive Mechanized Mining of Deep Hard Ore by Using High-frequency Crushing Hammer
    YAO Jinrui LI Xibing SUN Licheng WANG Mei YAO Hua WANG Qingping LI Wenfei WANG Shaofeng
    2021, 50(07):  27-33. 
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    With the increasing depth of deep hard rock mining， the drilling and blasting method has gradually failed to meet the requirements of deep hard rock mining.Mechanical excavation was proposed and developed to deal with the challenges brought by deep mining， and has been widely used in the fields of coal mining and tunnel excavation. In order to explore the application of non-explosive mechanized mining in deep hard rock mining， a mechanical mining test was carried out by excavating the pillar with airborne high-frequency crushing hammer in deep hard ore-rock. During the test， the scope of the excavation damage zone of the test pillar was monitored by digital borehole television. The application of non-explosive mechanized mining in deep hard rock mines was explored in terms of daily mining time， crushing hammer and excavator status， pillar morphology， mining amount， spalling ore lumpiness， dust condition， roof condition and shaking tooth wear condition of crushing hammer tip. The test results showed that the average thickness of the excavation damage zone of the test pillar reached 2.59 m， and the mining efficiency was high within this range. In the test， the overall cutting efficiency could reach 50.6 t/h， and the cutting efficiency of the excavated pillar could reach 158.2 t/h， which proves the feasibility of the application of mechanical mining in deep hard rock mines. In addition， mechanical mining also has the advantages of high utilization rate of working hours， small spalling ore lumpiness， less dust， and less excavation disturbance.
    Prediction of Unplanned Ore Dilution Based on BP Neural Network
    ZHAO Xingdong NIU Jia'an WANG Weiping, XIAO Yigai, SUN Guoquan, LI Lianchong Lü Xiangfeng
    2021, 50(07):  34-39. 
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    In order to eliminate the limitation of equivalent linear overbreak slough （ELOS） empirical graph method in estimate unplanned ore dilution，BP neural network algorithm was applied to establish the three-layers BP neural network prediction model with 6 hidden layer neurons by considering the modified stable number of stope， hydraulic radius， average deviation of borehole and powder factor as input variables and ELOS of quantified unplanned ore dilution as output variables. The training and testing of model was performed by 120 group samples， the fitting degree of the prediction model was 0.987 42， and the mean square error was 9×10-5， the relative error of the forecast was about 6%.The prediction method of unplanned ore dilution was proposed.The calculation of unplanned ore dilution was applied in the test stope of Sandaoqiao Pb-Zn Mine， the calculation results showed that the calculated value of the unplanned ore dilution based on BP neural network was 0.717 m， and the relative error between the calculated results and the measured results 0.7 m was 2.4%， which was better than the results of empirical graph method and numerical simulation analysis （0.80 m and 0.55 m）， BP neural network model could be applied to predict the unplanned ore dilution in actual mines.
    Inversion of Sliding Surface Position and Spatial Morphology of Open-pit High Slopes with Gently-inclined Soft Interlayers
    HU Bin, LIU Yang, CHANG Shuxiang, LI Jing, JIA Yalan,
    2021, 50(07):  40-49. 
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    The determination of the sliding surface is the key problem in slope treatment， but the traditional explorationtechnology in the process of sliding surface survey and identification often exists time-consuming， labor-consuming， damage to the slope， with security risks and other issues. To overcome the limitation of traditional sliding surface determination method， taking the high slope with gently-inclined soft interlayers of Huangshan Limestone Mine in Sichuan as an example， under the condition of emergency treatment of slope ， based on the comprehensive application of engineering geological analysis， space analytic geometric method， limit equilibrium method and strength reduction method， ainversion method of sliding surface was proposed， which takes engineering geological analysis method as the premise， spatial analytic geometry method and limit equilibrium method as the calculation and analysis means， and strength reduction method as the inspection guarantee. Firstly， the overall and local failure modes of the slope were determined according to engineering geological analysis. Secondly， the spatial morphology of the sliding surface at theforward and backward edges of the slope was determined by using the spatial analytical geometry method. Finally， the stability coefficient of the slope was calculated repeatedly by using the limit equilibrium method， and the specific position of the sliding surface was determined， and the sliding surface inversion results were verified by the finite element shear strength reduction method. The slope slides along the soft interlayers as a whole， and the forward and back edges were arc-shaped sliding failure. The results showed that the sliding surface was located at a position with a vertical distance of 26 m from the platform of 775 m to the soft interlayers. The slope stability coefficient calculated by finite element method shear strength reduction method is 1.00， and the feasibility and correctness of this method was proved. The above results provided a new idea for determining sliding surface and has certain reference significance for rapid identification and determination of similar slope sliding surface and emergency treatment of dangerous rock mass.
    Feasibility Study on Enhanced Permeability of Low Permeability Sandstone Type Uranium Deposit with Liquid CO2 Phase Transition Fracturing
    BAI Xin, LUO Guijun WANG Yan ZENG Sheng XUE Xilong FENG Nili
    2021, 50(07):  50-57. 
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    Safe and stable supply of uranium resources is of great significance for ensuring national security and promoting the sustainable and healthy development of the nuclear industry. Aiming at the technical bottleneck of the high-efficiency mining of low-permeability sandstone-type uranium deposits in our country， a technical idea of a low-permeability sandstone-type uranium deposit with liquid CO2 phase transition fracturing and high-efficiency mining method was proposed. That is， the liquid CO2 phase transition fracturing technology was used to generate a large number of interconnected fracture between the in-situ leaching extraction holes and injection holes to improve the seepage capacity of the low-permeability uranium ore. The theoretical method was used to calculate the influence radius of liquid CO2 phase transition fracturing， and the liquid CO2 phase transition fracturing and permeability enhancement in-situ leaching mining process was established. The system carried out a feasibility study on low-permeability sandstone-type uranium deposits with liquid CO2 phase transition fracturing to increase permeability and high-efficiency mining. The results showed that: The influence radius of liquid CO2 phase change fracturing to increase permeability technology was 6.53 m. This technology can achieve rock fracture failure under three-dimensional stress conditions， could effectively increase the distribution of rock damage and fracture network， and has the advantages of rock fracturing， reducing chemical precipitation and economic feasibility. The results of this paper provided a possible way to solve the problem of low permeability and low leaching rate in the process of in-situ leaching of sandstone-type uranium deposits， and would be of great significance to the future breakthrough of the low-permeability sandstone uranium ore problem with low leaching rate.
    Study on Stope Stress and Deformation Law and Stability of Stage and Subsequent Filling Method
    HU Chao DING Chenggong JIN Changyu DONG Longbin CHEN Wujiu
    2021, 50(07):  58-65. 
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    A certain iron mine adopts the stage open stope and subsequent filling method. At present， the stoping work of the first mining middle section of -450 m is about to end. It is planned to increase the stage height from the original 60 m to 90 m in the development of the new middle section of -390 m， and the stage height is increased by 50%. In order to study the stress and deformation law of steeply inclined thick ore body under the condition of stage open stope and subsequent filling mining， this paper adopts the method of combining similar material test and numerical simulation， considers the influence of the first mining middle section and multi panel area on the new middle section mining and filling， and obtains the stress and deformation law of stope pillar and surrounding rock through analysis.The results show that: in the process of mining and filling in the new middle section after the stage height is raised， the stress in the pillar will increase greatly after the pillar is exposed， and the shear failure of the pillar will be caused with the increase of stress concentration； The maximum deformation in the stope appears in the roof of the room in the middle panel， the maximum principal stress and plastic zone appear in the middle and lower position of the middle pillar， the maximum principal stress， settlement deformation and plastic zone are symmetrically distributed with large in the middle and small on both sides， and the minimum principal stress appears at the top corner of the room on both sides； The minimum principal stress and settlement deformation caused by interval mining are less than those caused by sequential mining， while the mining sequence of chamber has little effect on the maximum principal stress； With the increase of pillar width， the maximum and minimum principal stress， deformation value and plastic zone range in stope decrease gradually. The research results of this paper can be used for reference for similar mines at home and abroad.
    Study on Mix Proportion Optimization of Mixed Aggregate Filling Slurry with Limestone Powder
    HE Jianyuan WEN Zhenjiang WANG Yongding WANG Hu GAO Qian LI Hai LI Hongye
    2021, 50(07):  66-72. 
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    In view of the poor gradation of waste stone bar grit blended coarse aggregate in Jinchuan Mine， the problem of segregation of filling slurry is solved. Limestone aggregate is added to improve aggregate gradation and improve filling effect. Firstly， the physical and chemical analysis of the aggregate is carried out， and on this basis， the particle size distribution analysis of the mixed aggregate is carried out. Secondly， the strength test of the mixed aggregate filled with limestone powder and the pipe transportation characteristics of the slurry are carried out. Then， based on the test results， the BP neural network model is established to predict the strength of the filling body and the pipe transportation characteristics of the slurry，and the mix proportion of the mixed aggregate filling slurry is optimized. The study results show that: adding appropriate amount of limestone powder can not only effectively improve the particle size distribution and strength of the filling body， but also improve the fluidity of the filling slurry， which is beneficial to the pipeline transportation characteristics of the filling slurry， and can significantly improve the filling effect.The optimal proportion of the filling slurry is as follows: the amount of cementitious material is 310 kg/m3， the content of limestone powder is 12.3%， and the mass concentration of slurry is 80%.It has been verified by sampling during industrial filling that The slump， consistency， bleeding rate， 3 d， 7 d and 28 d compressive strength are 25.41 cm， 9.31 cm， 6.7%， 2.7 MPa， 5.1 MPa and 10.6 MPa respectively， which can meet the requirements of mine industrial filling， and the cost of unit filling is reduced by 21%.
    Comparison of Force Chain Evolution Characteristics During Ore Drawing Process Between Short-hole Shrinkage Method and Synchronous Filling Shrinkage Method
    LIU Enjiang CHEN Qingfa LIU Jun
    2021, 50(07):  73-82. 
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    Compared with short-hole shrinkage method， synchronous filling shrinkage method has a significant effect on ore drawing law owing to flexible isolation layer laid before a large number of ore drawing. Based on common features of two mining methods， with the help of the discrete element software， the comparative study on the evolution characteristics of the force chain in the ore drawing process between the short-hole shrinkage method and the synchronous filling shrinkage method is carried out. The results show that in the drawing process of the two mining methods， both the proportion of strong contact and force chain contact increase with the drawing times， the law of change is also different. The number of force chains varies with the increase of drawing times， but the probability distribution law of force chain length is highly consistent， which decreases exponentially. Compared with the short-hole shrinkage method， although the fluctuation range of the force chain strength in the system is small during the drawing process of synchronous filling shrinkage method， but the probability distribution of the force chain strength of the two methods first increases in exponential form and then decreases in exponential form under different drawing nodes， showing the same variation law. In the process of ore drawing， the direction distribution of force chain in the granular materials systems shows obvious change in different stages， the variation law of force chain direction and anisotropy degree characterization parameter have significant difference in each stage. The research results have certain significance for the further study on the ore flow law in the drawing process of synchronous filling shrinkage method.
    Study on Suitability Evaluation of Surface Building Construction above Residual Space after Filling in Iron Mine
    GUO Wenyan, CHEN Qingtong, JIA Xinguo, WANG Zhijie,
    2021, 50(07):  83-88. 
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    In order to evaluate the suitability of surface building which constructed above the residual space after filling in Zhangmatun Iron Mine gob， the research methods that combined field measurements， theoretical analysis and empirical analogy were used， and the roof stability of residual space of three different types （including small， contiguous and up and down two layers of goaf） of gob was analyzed， and the residual deformation areas of different degrees of surface were divided， moreover，the relative relationship between the affected depth by building load and the failure height of overburden was studied， and the settlement characteristics of surface monitoring points were analyzed， then the construction suitability of building was evaluated and the safety guarantee measures for the construction site were proposed. The results showed that the roof of the residual space of the gob is stable without large-scale collapse，75.8 % of the regional of the buildings in the construction site are subject to grade I slight damage and deformation， and another 15.6 % of which are subject to grade II slight damage and deformation， thus， the damage risk of buildings is low. There had no effect on the stability of the gob when the building load added to 360 kPa， the overall settlement of the surface is small， so the stability of the residual space of the gob is good， and the suitability for buildings construction （the building height below 36 m） is good.
    Experimental Study on the Relationship Between the Width of Pre-split Blasting Joints and the Density of Line Charges
    WANG Yaqiang YANG Haitao, LI Chen MA Haiyang LI Erbao,
    2021, 50(07):  89-95. 
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    With the application of high-step steep slope mining technology in open-pit mines in China，pre-splitting blasting control technology has become an important means to protect slopes and control secondary disasters caused by blasting vibration. In order to accurately calculate the key process parameters of pre-splitting blasting (line charge density) and the width of pre-splitting joints under different line charge densities in the mine's adjacent area， the Wushan Copper-molybdenum Mine was taken as an example， combined with rock mass failure judgment and the explosive pressure law of explosives， the formula for calculating the charge density of the pre-split blasting line was theoretically deduced，and the theoretical formula for the charge density of the pre-split blasting line when the pre-split hole was cracked and the pre-crack penetrates was obtained， combined with the typical mine lithology-biotite granite，the physical and mechanical test parameters were calculated.It is showed that the linear charge density of typical rock cracking and pre-fracture penetration in the mine were 0.196 kg/m and 0.528 kg/m， respectively.Through numerical simulation and regression analysis， the relationship between the line charge density and the width of the pre-splitting blasting seam was analyzed， and four schemes of line charge density 0.50， 0.54， 0.57， and 0.6 kg/m were selected. Statistics on the failure of grid elements in the whole process of forming through cracks showed that when the linear charge density was 0.5~0.6 kg/m， the pre-fracture width and the linear charge density could be described by the following functional relationship: y=- 172x2+213x-60 （R2=0.98）， and the width of the pre-crack increased with the increase of the line charge density. An on-site pre-splitting blasting test was carried out in the test mine， and the blasting vibration at 30 m behind the pre-crack was monitored. The results showed that the comprehensive vibration reduction rate at 30 m behind the penetrating pre-crack reached more than 31.3%； The pre-crack has the phenomenon of bonding and bonding， and the damping effect was significantly reduced. Compared with the pre-crack penetration， the vibration damping rate wasreduced by 4.3% to 5.6%； When the pre-crack is penetrated， the line charge density further increased to 0.06 kg/m，the vibration reduction rate was only increased by 1.3%.The further analysis showed that after the pre-crack was completely penetrated， continuing to increase the line charge density has no obvious significance for the improvement of the vibration reduction effect.
    Fine Acceptance of Open-pit Mine Goaf based on UAV Aerial Survey Technology
    ZHANG Bingbing XU Longxing ZHANG Pu ZHANG Gangtao
    2021, 50(07):  96-101. 
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    The traditional acceptance of goaf treatment effect in open-pit mine is mainly based on experience method. However，there are some limitations in macroscopic analysis from the overall shape of collapse， so it is difficult to accurately determine the actual effect. In order to evaluate the goaf treatment effect more efficiently， low-altitude UAV aerial survey technology is proposed， which is a non-contact surveying and mapping method， with good safety and reliable precision and high efficiency. The connotation of fine acceptance of goaf is given， which is applied in the treatment stage of blind goaf left by 649 m platform in Dabaoshan Mine. The DJI Phantom 4 RTK small UAV equipped with high-definition single lens was used to realize 5-lens aerial survey with altitude of 100 m. The two-period 3D model information of blind goaf before and after blasting was obtained， and the accuracy verification met the requirements of 1∶500 topographic drawing. The South IData software is used to realize the combination of blind goaf range line and three-dimensional model. The calculation results show that the increase rate of filling relative height is 110%~200% after blasting. Combined with multi-angle aerial images and actual excavation operation， it is verified that the blind goaf is well processed. The practice shows that low-altitude UAV aerial survey technology is feasible in fine acceptance of goaf treatment effect of open-pit mine.
    Research on New Technology of Enhanced Separation Recovery of Fine-grained Iron Minerals in Donganshan Iron Mine
    YANG Guang ZHOU Libo, LI Wenbo, ZHANG Dong YUAN Libin WEI Zhi YANG Feng,
    2021, 50(07):  102-109. 
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    In order to solve the problem of the high grade of high intensity magnetic tailing in Donganshan， and the existing high intensity magnetic equipment cannot effectively recover fine iron ore. Based on the process mineralogy of samples and the theory of agglomeration separation， the effects of reagent dosage and magnetic separation parameters on the magnetic separation index were investigated through agglomeration-magnetic separation test， and the effects of selective agglomeration pretreatment on reverse flotation index were also investigated through reverse flotation test. The agglomeration-magnetic separation test results indicated that under the conditions of sodium silicate dosage of 500 g/t， DLA dosage of 250 g/t， stirring speed of 900 r/min， stirring time of 5 min， pulp pH value of 10.0， frequency of 170 times/min， pulp flow rate of 120 mL/s and magnetic separation background field strength of 1.0 T， the magnetic separation index with iron grade of 47.65% and iron recovery of 71.54% can be obtained. Compared with non-additive agent， the magnetic separation recovery was increased by 4.58 percentage points，and the beneficiation efficiency was increased by 2.42 percentage points. The reverse flotation test results of mixed magnetic concentrate show that: compared with the conventional high gradient high intensity magnetic separation reverse flotation process， the final concentrate grade obtained by selective agglomeration high gradient high intensity magnetic separation reverse flotation process has little change， while the iron recovery of mixed magnetic concentrate has increased by 2.05 percentage points， and the iron recovery of final flotation concentrate has increased by 4.37 percentage points.
    Processing Mineralogical Study of Qidashan Xishilazi Hematite and Limonite
    LIU Yingzhi, ZHANG Shumin, LI Yanjun, YUAN Shuai,
    2021, 50(07):  110-114. 
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    In order to improve the separation effect of hematite and limonite in Xishilazi， systematic process mineralogy research was carried out on representative ores through chemical multi-element analysis， XRD analysis， iron phase analysis and so on. The results showed that:①The TFe grade of hematite and limonite in Xishilazi of Qidashan is 27.88%， and the contents of the main gangue component SiO2 is 55.65%. The contents of harmful elements P and S in the ore are 0.006% and 0.005%， respectively. ②The main metallic minerals in the ore are hematite and magnetite， followed by a small amount of limonite and a trace of pyrite. Non-metallic minerals are mainly quartz and a small amount of chlorite and muscovite. The iron in the ores mainly occurs in hematite and limonite， followed by magnetic iron. ③The ore structure consists of automorphic to semi-automorphic crystal structure， pseudomorphic structure， residual structure and metasomatic structure. The ore is mainly in the form of striped structure and disseminated structure. ④Primary hematite and magnetite are mutually embedded in the ore. Magnetite is oxidized and altered to generate pseudo hematite， and secondary hematite is speckled， veined， reticulated and spider-like distribution in the magnetite. Hematite and magnetite are immiscible intergranular particles， and the two are difficult to dissociate from each other and could be recovered together. ⑤Quartz is mainly produced in automorphic granular aggregates， with fine dissemination particle size， and a small amount of fine chlorite and muscoite are embedded between particles. ⑥Magnetite and hematite are mainly distributed in medium grains， and the contents of fine grains is large. The distribution rate bellow 0.038 mm grain size is as high as 20.22%. It is difficult to achieve completely monomer separation and easy to be lost in tailings， causing difficult in recovery.
    Experimental Research on Comprehensive Recovery of Iron-sulfur-copper Polymetallic Ore in Anhui
    WANG Zhifeng LI Guidong, PENG Guixiong CHEN Dujuan
    2021, 50(07):  115-118. 
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    The ores containing iron and copper in Anhui is a typical polymetallic associated ore， with close symbiosis among minerals and complex distribution.The metallic minerals in the ore are mainly magnetite， and a small amount of pyrite， chalcopyrite， pyrrhotite and so on. The non-metallic minerals are mainly serpentine， diopside， tremolite and so on.In order to comprehensively recover the valuable components in the ore， the process flow of copper-sulfur mixed floatation，copper-sulfur separation and magnetic separation of mixed tailings was adopted to treat the ores on the basis of the condition test. The copper concentrate with Cu grade of 22.18% and Cu recovery rate of 76.85%， sulfur concentrate with S grade of 43.29%，S recovery rate of 45.71%，Co grade of 0.43%， Co recovery rate of 45.04%，and iron concentrate with Fe grade of 62.36%，Fe recovery rate of 93.09%，S contents of 0.18% was finally obtained through the whole process test.The test indexes are good and the associated component Co effectively enriched in the sulfur concentrate，indicating the comprehensive recovery of the valuable metals.
    Nielsen Gravity Concentration Combined with Low Cyanide Leaching Test Research for a Gold Mine in Inner Mongoli
    ZHU Yimin, GE Wencheng, ZHANG Shumin, YANG Xinhua LIU Jie,
    2021, 50(07):  119-123. 
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    A gold deposit in Inner Mongolia contains gold of 2.83 g/t.At present，the leaching process of sodium cyanide and resin adsorption is adopted to extract gold，and the total cyanide content in the leaching residue is as high as 50 mg/kg. In order to reduce the dosage of cyanide， Nielsen gravity separation and low-cyanide leaching process for tailings tests were conducted，so as to meet the filling technology standard. The condition including tailings grinding fineness， dosage of Jinxin and calcium oxide，the liquid-solid ratio，leaching time on leaching effect were studied. The results showed that:① Under the conditions of grinding fineness of -0.043 mm accounting for 87%，separation G value of 80 G，fluidized water flow of 3 L/min and feeding concentration of 50%， the process of "one roughing and two scavenging" was used in Nelson gravity separation.The cumulative recovery rate of gold reached 55.91% and the cumulative grade of gold was 35.48 g/t. Gold grade of gravity separation tailings is 1.34 g/t.② Low cyanide leaching conditions tests for gravity separation tailings were carried out. With the optimum grinding fineness -0.043 mm accounting for 79%，the dosage of calcium oxide of 5 kg/t，the dosage of Jinxin of 1 200 g/t，the leaching time of 36 h，the liquid-solid ratio of 1.5 mL/g，the gold leaching rate was 91.88% at this time. The comprehensive recovery rate of gravity separation and leaching process reached 96.42%. Under the above conditions， the adsorption rate of gold was 86.94% when the precious solution was treated by resin adsorption，and the comprehensive recovery rate of gold in the whole process of gravity separation， leaching and adsorption was 91.13%，indicating good indexes. The total cyanide concentration of the leaching residue was 0.50 mg/kg，which reached the technical standard of tailings filling.
    Process Mineralogy Study of a Refractory Arsenic-containing Gold Ore in Qinghai
    HAN Yunxiang, YANG Hongying, TONG Linlin, ZHANG Zhonghui LI Wei
    2021, 50(07):  124-129. 
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    The ore properties of a refractory arsenic-containing gold ore in Qinghai is complex， and the grade and recovery rate of the produced gold concentrate are low. In order to fully grasp the ore properties and improve the gold grade and recovery rate， the process mineralogy of the ore was studied systematically by means of polarizing microscope and field emission scanning electron microscope （SEM）. The results showed that: ①The distribution of gold grade in different mining areas is extremely uneven， and the average gold grade is 3.0 g/t. The main metallic minerals in the ore are pyrite， a small amount of sphalerite and galena，trace chalcopyrite and a small amount of arsenopyrite. The main non-metallic minerals are quartz and feldspar， as well as part of epidote， diopside， sericite and calcite. ② The main non-metallic minerals in the ore are the electrum of 81.58%， the rest are the natural gold of 14.80% and the kustelite of 3.62%. The gold mineral particles in the ore are fine with the maximum particle size of 31 μm and the minimum particle size of 2 μm，in which the average particle size is of 10 μm. The contents of the fine and minuteness gold are accounting for 93.39% and 6.64%， respectively. The occurrence of gold minerals can be divided into the three types of encapsulated gold， interstitial gold and fissure gold with 79.30% of encapsulated gold， 12.76% of interstitial gold and 7.94% of fissure gold. The morphology of gold minerals is mainly round granular， and the rest are long strip and irregular. ③The main gold-bearing minerals in the ore are pyrite and a small amount of arsenopyrite. Compared with the iron contents in ideal pyrite， the iron contents in common pyrite and gold-bearing pyrite in the ore is 2.06 percentage point and 2.66 percentage point lower， respectively， showing the characteristics of low iron and high sulfur. The contents of iron and arsenic in common arsenopyrite and gold-bearing arsenopyrite were lower than ideal ones， and the contents of iron and arsenic in common arsenopyrite were 1.65 percentage point and 3.30 percentage point lower， respectively. The contents of iron and arsenic in gold-bearing arsenopyrite are 0.50 percentage point and 6.15 percentage point lower， respectively. The contents of sulfur in common arsenopyrite and gold-bearing arsenopyrite are 4.28 percentage point and 6.65 percentage point higher than that in ideal arsenopyrite， respectively. ④ The main gold-bearing mineral in the ore is pyrite and the gold particle size is micro-fine. It is suggested to improve the monomer disintegration degree of pyrite and strengthen the collection of pyrite to further increase the recovery rate of the gold.
    Application of Inhibitor EMY-01 on Flotation Separation of High Clay Type Pyrite
    ZHAO Kaile, YAN Wu, YANG Weiwei GU Guohua KANG Bowen, DENG Jian, GAO Zhiyong
    2021, 50(07):  130-134. 
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    Clay minerals mainly include kaolinite， pyrophyllite， montmorillonite， chlorite， talc and other layered aluminosilicate minerals. These minerals usually have low hardness and are easy to float and slime in the process of grinding and flotation， which worsens the flotation environment of target minerals. The development and application of new high-efficiency selective inhibitors of clay minerals are the key technologies for stable and effective separation of high clay content minerals. Aiming at the flotation separation of a high clay pyrite in Southwest， based on the structure and properties of clay minerals， a special depressant for aluminosilicate gangue and "sequential regulation of the action of collector inhibitors and enhanced selective suppression" floating sulfur process were developed. Conditional test results showed that when the content of -0.045 mm in the ore is 91.16% and the amount of inhibitor EMY-01 is 900 g/t， good test results could be obtained. The closed-circuit test results based on the conditional test showed that EMY-01 as an inhibitor could obtain sulfur concentrate with sulfur grade of 50.16% and sulfur recovery rate of 97.12%. The results showed that the use of EMY-01 as an inhibitor could realize the effective development and utilization of high clay content sulfide ores.
    Flotation Difference between Diaspore and Kaolinite with Collector CTAB and Its Molecular Dynamics Simulation
    WEN Yanlong ZHANG Suhong
    2021, 50(07):  135-141. 
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    In order to study the effect of quaternary ammonium collectors on the reverse flotation of bauxite， the effects of cetyl trimethylammonium bromide （CTAB） on the flotation recovery of diasphalite and kaolinite were investigated using dodecyl amine （DDA） as reference collector.The mechanism of action was systematically analyzed by FTIR analysis， Zeta potential detection， adsorption capacity measurement and molecular dynamics simulation.The flotation test results showed that CTAB showed the better flotation separation effect compared with DDA. Under the condition of pH of 4 and CTAB concentration of 2×10-4 mol/L， the flotation recovery rate difference of diaspore and kaolinite in the flotation test of pure minerals is up to 51.70 percentage.A concentrate with Al2O3 grade of 71.73%， recovery rate of 71.26% and SiO2 contents of 9.43% was obtained by artificial ore mixing test. The Al/Si ratio reached to 7.60.The results of mechanism analysis showed that the collector CTAB adsorbs on both diaspore and kaolinite， and the adsorption amount on the surface of kaolinite is greater than that on the surface of diaspore， which both are physical adsorption.The results of molecular dynamics simulation showed that the total interaction energy between collector CTAB and kaolinite is 2.29 times that of collector CTAB on diaspore. Therefore， CTAB molecules are adsorbed on the surface of kaolinite firstly， which has high selectivity and is beneficial to reverse flotation.
    Experimental Study on Magnetization Roasting and Magnetic Separation of an Iron Tailings in Ansteel
    ZHANG Yi, YU Ying ZHANG Wuzhi, GAO Peng,
    2021, 50(07):  142-145. 
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    In order to determine the suitable conditions of magnetization roasting， the process of magnetization roasting and magnetic separation was adopted to conduct a systematic experimental study on an iron tailings from Anshan Iron and Steel Company. The Influence of roasting temperature， roasting time， reducing gas concentration and gas flow rate on the effect of magnetization roasting were investigated. The results showed that: ① The TFe grade of Anshan iron tailings is 14.70% and the main impurity SiO2 contents is 66.17%. The contents of harmful elements， such as phosphorus， sulfur and sodium are less. The iron in the iron tailings mainly exists in the form of hematite and limonite， with the distribution rate of 83.87%. The main useful minerals in the iron tailings are magnetite and hematite， and the main gangue mineral is quartz. ② The suitable roasting conditions of the iron tailings are as follows: roasting temperature of 580 ℃， roasting time of 5 min， CO concentration of 30%， gas flow rate of 500 mL/min. Under the suitable conditions， magnetic concentrate with TFe grade of 62.17% and TFe recovery rate of 84.02% was obtained by low intensity magnetic separation of the roasted products with the magnetic field intensity of 87.12 kA/m. ③ The results of iron phase analysis of roasted products showed that the contents and distribution of magnetic iron in the samples were significantly increased after magnetization roasting， while the contents and distribution of iron in hematite and limonite were significantly decreased. The results of XRD patterns of products with different calcination time further indicate that hematite in iron tailings is transformed into magnetite. The research results could provide reference for the development and utilization of tailings of the same type.
    Parameter Optimization on Long Distance Pipeline Transportation of Coarse Ore Pulp from Semiautomatic Grinding in Tianjia Village
    WANG Zhijie
    2021, 50(07):  146-152. 
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    The semi-automatic grinding products of Baima Iron Mine in Tianjia Village were transported to the grinding plant by 6.5 km pipeline， which conveying particle size was -3 mm. Due to unreasonable design parameters at the initial stage of production， the pipeline was often blocked and cannot run normally. Through the analysis of the granularity， flow rate and velocity of ore pulp， some researches and improvements were carried out. The results show that the coarse particle size of export pulp decreases and the fine particle size increases， and the flow rate and velocity decrease and the concentration increase to form blockage in the conveying process. On this basis， the conveying system was optimized and transformed: the mesh parameters of the semi-autogrinding-sieve plate were adjusted to 2.5 mm×12 mm， the diameter of the impeller of the first stage pump was changed from 965 mm to 990 mm， the pump pool structure was transformed from flat bottom four corners to three-sided slope structure， and the conveying system ran smoothly after the transformation. In order to improve the processing capacity of semi-autogenic mill as much as possible， the parameters of semi-autogenic mill after optimization， slurry pipe size， slurry flow rate and velocity were investigated. The results show that the slurry concentration is improved after optimization， and the conveying flow rate and velocity exceed the design indexes， ensuring the stability of pipeline transportation. To study the feasibility of conveying system to further optimize and carry out the experimental study of the rheological properties of the pulp， test the original pulp body sedimentation characteristics， different concentrations of the rheological properties of pulp， the critical flow velocity， friction loss are analyzed and calculated by the comprehensive analysis on the impact of parameters such as concentration， particle size on transport， on the basis of adjust sieve plate size for 2 mm × 12 mm. Adjust two pump impellers of the first pump station to 870 mm and 980 mm respectively. After optimizing the parameters of the conveying system， the average time of the semi-automatic grinding platform is 613 t/h， and the flow rate of the pipeline is 3.44 m/s. It realizes the stable operation of the long-distance pipeline conveying of coarse slurry， which is of reference significance to the pipeline conveying of mining enterprises.
    Two-stage Mineralization and Its Ore-prospecting Significance in Niubiziliang Cu-Ni Deposit，Qinghai Province
    XU Xinwen DUAN Jianhua LIU Jiangfeng SHAO Ji YANG Xiaohong XU Jiaqiu
    2021, 50(07):  153-164. 
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    Niubiziliang Cu-Ni Deposit is the most representative one in the Aerjin orogenic belt in the northwest margin of Qinghai Province，gold mineralization has been discovered in the mining area.By focusing on the characteristics of Cu-Ni deposit and gold mineralization， prospecting potential，prospecting prospect and prospecting direction，it is shown that:①There are two stages of mineralization in the mining area. The early stage is the typical magmatic fusion-penetration type Cu-Ni mineralization controlled by the ultrabasic rocks of the late Devonian ，and the late stage is the typical tectonic alteration type gold mineralization controlled by the east-west faults passing through the rock masses， which are all located in the ultrabasic-basic rock masses of the Devonian； ②The prospecting prospect of copper and nickel deposit in the mining area is large，No.Ⅲ， No.Ⅳ， No.Ⅰ rock mass are all have prospecting potential，the prospecting prospect of the newly discovered gold mineralization is also large；③The subduction section of the southeast of No.III rock mass and the center of the “rock basin” of No.IV and No.I rock mass are the prospecting directions of Cu-Ni deposit in the mining area，the ore body (mineralization) of the existing gold bearing structural alteration belt and the delineated 1∶25 000 geochemical gold comprehensive anomaly are the prospecting directions of gold deposit；④The discovery and study of two-stage mineralization in the area is of great significance.The discovery of gold mineralization provides a new idea for ore prospecting in the area， and also provides a new opportunity for Cu-Ni deposit prospecting in the area.Breakthroughs will be made in the prospecting for gold in the early stage and the prospecting for Cu-Ni ore in the area.
    A New Quality Guided Phase Unwrapping Algorithm for Coal Mining Area Subsidence Monitoring
    LIU Wanli ZHANG Qiuzhao HU Jiang
    2021, 50(07):  165-171. 
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    The InSAR interferogram of coal mine subsidence area is usually characterized by dense fringes，large noise and many residuals. The phase unwrapping method based on quality map is relatively stable when unwrapping the phase of this kind of interferogram. However， different quality indexes tend to focus on temporal correlation or spatial correlation unilaterally， which often leads to unsatisfied unwrapping results. In this paper，a new quality index combining phase derivative variation and correlation coefficient is proposed， which not only considers the temporal coherence between pixels， but also takes into account their spatial similarity. It is more suitable for phase unwrapping of InSAR in mine subsidence area. A set of simulated interferometric phase unwrapping results indicates that the new quality index can improve the unwrapping accuracy and avoid large error accumulation compared with phase derivative variation and correlation coefficient index. The unwrapping results of a set of real mine subsidence interferograms with complex ground cover and high noise show that the new quality index is reliable， which can effectively avoid the low unwrapping accuracy caused by the accumulation of high-quality regional errors.
    Analysis of Terrain Change Characteristics and Disaster Causing Points under Mining Disturbance in Western Mountainous Area
    XI Baoshun GAO Yingui YANG Bin LI Liang KONG Wanjun
    2021, 50(07):  172-178. 
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    The terrain change after mining is a practical problem faced by coal production， the mining subsidence in eastern plain area has been studied in detail. However， due to the influence of terrain factors in western mountainous area， how to accurately obtain the subsidence data and the law of surface change still need to be further discussed. In order to determine the law of terrain change in mountainous area under mining disturbance and provide technical support for geological disaster prevention and control in mining area， this paper takes the mining disturbance area of a mining face in western mountainous area as an example. Firstly， rapidly obtain the digital image of the research area by UAV， generate multi-phase digital elevation model （DEM）， get the subsidence basin of the survey area， and study the subsidence of the surface with the mining face. Then， DEM is used to extract the slope， aspect and relief information of the study area， and the overall change of the terrain before and after mining is obtained. The analysis results show that: the surface change in the study area is obviously affected by underground mining activities， specifically for the working face after mining， the overall slope becomes gentle， and the undulation decreases. With the mining of the subsequent working face， the slope and undulation increase， but the change is small. Using the characteristics of slope change to obtain the surface disaster causing points caused by underground mining， combined with the original elevation， original slope and mining subsidence， the distribution of disaster causing points is analyzed. It is found that the disaster causing points are mostly located on both sides of valleys and roads with higher altitude， smaller original slope and lower vegetation coverage. Through the analysis of the location of disaster causing points can provide technical reference for the follow-up slope treatment， road maintenance and land reclamation in the mining area. Keywords mining subsidence，DEM，UAV， terrain characteristics，disaster point
    Design and Implementation of Multi-protocol Communication Platform for Mine Automation
    MA Ning ZHANG Guangming WANG Run
    2021, 50(07):  179-185. 
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    With ARM Cortex-M3 kernel micro-controller， the multiple protocol communication platform of mine automation system is designed and implemented. The system architecture consists of micro-controller， real-time operating system and embedded TCP/IP protocol stack. With graphic display interface， TFT-LCD is driven by the SPI interface. After JPEG compression， the size of the image file is about 45 kB， and it needs about 600 ms transmission time， which can meet the requirements of communication platform. In order to improve the stability of the power supply， some technical measures are adopted to reduce noise and prevent interference. In order to facilitate the system debugging， RS232 serial communication is provided for PC to establish data connection， which can support technicians to observe the running state of the system with a portable computer or PC. Through RS232-485 converter， mine automation system equipment access can be realized. By porting the embedded TCP/IP protocol stack and embedded file system EFSL， file transmission and embedded Web server are both implemented. Basic information of the mine equipment can be displayed on real-time.The experimental results show that，through the integrated design of the mine automation communication platform， coordination and correlation operation of each subsystem can be realized， and the information-island problem in mines for years can be avoided. Seamless integration of the data collected from the whole mine is achieved on the Web， which can search and track all the dynamic information of stope environment changes and production process in a fast and real-time manner， monitor mine operation and decision-making in real time， command mine production and operation， trace accidents and make early warnings.
    Wear Reasons and Countermeasures of Guide Walking Device of Underground Bauxite Mining Machine
    ZHANG Liqiang,
    2021, 50(07):  186-192. 
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    In view of the wear failure problem of the guide walking device of the underground bauxite mining machine， according to the wear phenomenon of each part， the actual wear state is analyzed and verified， the meshing position diagram of running wheel and track tooth surface corresponding to different comprehensive wear is given， and the influence factors are analyzed.In this paper， the influence factors of rock fragmentation and hardness， comprehensive wear of guide shoe and track， and mining technology are analyzed in detail. According to the analysis， the countermeasures is put forward to solve the wear and tear， and expounds in detail from three aspects of improving mining conditions， optimizing equipment and strengthening maintenance. The work of improvement and verification has been completed，after the structure improvement， the guide walking device has been tested twice. Through the test of nearly half a year， the life of the new guide walking device of the mining machine has been increased from 1 month to more than 3 months. Based on the above discussion results，the further analysis results show that the key point is to reduce the influence of hard lump rock on the meshing system of track， and the cooperation of equipment， maintenance and environment is more favorable to the improvement of wear problem.The further research direction of solving the problem of wear is put forward， including the track structure， the matching structure of guiding device and the method of separating the hard massive mineral.
    Development and Industrial Application of Coarse Particle Vertical Ring High Gradient Magnetic Separator
    LI Zeping RAO Yuhuan XIE Zhifeng DING Li WAN Peng XIONG Dahe ZENG Zhaoke
    2021, 50(07):  193-197. 
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    Traditional vertical ring high gradient magnetic separator（VPHGMS） is used only for processing of fine grained minerals. In order to adapt to the actual production needs， coarse particle VPHGMS was developed for direct separation of coarse particle and the equipment was applied for pre-discarding of the tailings， which greatly reduces the production loading for the following operation. Aiming at the ore properties of Zhouyoufang Iron Mine in Anhui Province， two SLon-3500 coarse particle VPHGMS have been successfully applied in the technological transformation. Under the conditions of the feeding particle size of -4 mm， the magnetic induction intensity of twice roughing separation of 0.7 and 1.0 T respectively and the diameter of rod medium of 5 mm， a good discarding indexes has been obtained. At the same time， a large amount of waste rock generated by pre-discarding is sold to the construction sand industry， which created considerable economic， social and environmental benefits. A coarse concentrate with a TFe grade of 62.11% and a TFe recovery rate of 96.37% was obtained by applying a coarse particle VPHGMS to a high quality hematite concentrator in India under the conditions of feeding particle size of -5 mm， the magnetic induction intensity of twice roughing separation of 0.8 and 1.1 T respectively and rod medium diameter of 6 mm， indicating the better indexes.
    Design and Application of Pneumatic Cleaning and Flow Aid System for High Viscosity Material Silo
    WU Youjian, XU Jinjun JI Wanjian, LIU Jian, YAN Wei,
    2021, 50(07):  198-205. 
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    In order to study the effect of material properties and silo structure on material flow capacity， and solutions for high-viscosity materials blocking inside the silo，the influence of the water content and particle size of the material in the fine ore silo of the Heshangqiao Concentrator on the friction angle of the material and the influence of the semi-top angle of the silo and the size of the discharge port on the flow performance of the material were analyzed based on Jenike shear theory.The results showed that the internal friction angle of the materials in the powder ore silo increases with the increase of the water content， when the water content between 10% and 11%， the internal friction angle reaches the maximum value of 47.2°， and then gradually decreases with the increase of the water content. The internal friction angle of the material gradually decreases with the increase of the particle size. When the particle size exceed 3 mm， the change of the internal friction angle tends to be gentle， stable at about 42°. The unreasonable design of the semi-top angle and the size of the discharge port can easily cause the blockage of the warehouse.Based on the above research results， a pneumatic cleaning and flow aid scheme is proposed aiming at the blockage of the powder ore silo. The results showed the effective volume ratio and effective reserves of the powder ore silo are increased by more than 40%，which increases the benefits of more than 14 million yuan for the concentrator under the premise of an annual processing capacity of 5 million tons.
    Experiment Study on the Preparation of Polyaluminum Chloride with Secondary Aluminum Dross
    SHI Jiali HUANG Zili QIN Qingwei YUAN Chenguang CHEN Jingzhi ZHOU Yi
    2021, 50(07):  206-210. 
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    Secondary aluminum dross is a main by-product of aluminum industrial production with complex composition and high salt content. The output of secondary aluminum dross in a secondary aluminum plant in Xiangyang is huge， and long-term storage poses a certain threat to the environment. In order to reduce the pollution to the environment and realize the high- value utilization of secondary aluminum dross，polyaluminum chloride was prepared by process of water washing pretreatment， hydrochloric acid leaching and polymerization maturing.The effects of polymerization temperature， polymerization time， polymerization pH value on the alumina contents and basicity of polyaluminum chloride were investigated， and the polyaluminum chloride prepared under optimized conditions was characterized by XRD， scanning electron microscopy and infrared spectrum. The results showed that the production prepared under the optimized conditions of polymerization temperature of 70 ℃， polymerization time of 5 h and polymerization pH of 3.0 displayed alumina contents and basicity of 9.09% and 46.30%， respectively.All indicators of the product were up to the national quality standards. The XRD and scanning electron microscopy analysis showed that the contents of metal impurities in the synthesized polyaluminum chloride was relatively low， and the main substance was sodium chloride. The infrared spectrum indicated that hydroxyl and polymeric aluminum were presented in the polyaluminum chloride molecule.
    Preparation of High Quality Iron Oxide Red by Purification Solution of Titanium By-products Ferrous Sulfate
    QIAN Youjun, PEI Xiaodong, LUO Yanhua, LI Xiaoxiang,
    2021, 50(07):  211-215. 
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    In order to find a new way of iron oxide red for soft magnetic ferrite and realize the comprehensive utilization of ferrous sulfate， ferrous sulfate purification solution of titanium by-product was used as the raw materials for synthesis of α-Fe2O3. Firstly， precursor was prepared by oxidation synthesis in liquid-phase through regulating pH value with ammonia solution， then the precursor production was calcined for preparation of the iron oxide red. The effects of pH value， initial Fe2+ concentration， calcination temperature and calcination time on the crystal structure， crystal morphology， impurity contents and specific surface area of the products were investigated by XRD， SEM， ICP， high frequency infrared carbon sulfur analyzer and specific surface area analyzer. The results showed that at initial Fe2+ concentration of 70 g/L， the precursor of high purity， low impurity contents and large specific surface area was obtained by accurately controlling the feeding speed of ammonia for ensuring the pH value of the system maintained within 5.0. Then， the precursor production was calcined of 2 h under the temperature of 760 ℃， the high quality iron oxide red product of Fe2O3 purity of 99.68%， SiO2 contents of 0.005 4%， S contents of 0.032% and specific surface area of 3.576 m2/g was obtained， which was the ideal raw material for the production of high-performance soft magnetic ferrite.
    Study on Mechanical Properties and Microstructures of Portland Cement with High Magnesium Nickel Slag Addition
    DONG Yaowei LI Wei
    2021, 50(07):  216-220. 
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    In order to explore the influence of the high magnesium nickel slag addition on the coalgulation time， hardening mechanical properties and microstructure， the coalgulation time and mechanical properties of high magnesium nickel slag/cement slurry under different mix ratio was studied. The influence of high magnesium nickel slag addition on the phase composition and microstructure of the hardened body was analyzed by XRD and SEM and the relationship between high magnesium nickel slag addition and the pore structure development of hardened body was analyzed by using specific surface area analyzer. The results showed that: ① the incorporation of high magnesium nickel slag postpones the coalgulation time of slurry. In the case of high magnesium nickel slag addition of 30%， the initial and final setting times of the hardened body of high magnesium nickel slag/cement were 103 min and 314 min， respectively， which were 66.13% and 69.73% longer than those without high magnesium nickel slag.②With the addition of high magnesium nickel slag， the compressive strength of hardened body at each age increases first and then decreases. When the contents of high magnesium nickel slag was 20%， the compressive strength of hardened body at 7 d and 28 d were 39.4 MPa and 52.8 MPa， respectively， which were 17.61% and 16.82% higher than that of blank group.With the addition of high magnesium nickel slag， the flexural strength of hardened body at each age increases first and then decreases. When the contents of high magnesium nickel slag was 20%， the flexural strength of hardened body at 7 d and 28 d reached 6.5 MPa and 8.2 MPa， respectively， which increased by 16.07% and 7.89% compared with blank group. ③X-ray diffraction analysis showed that the addition of high magnesium nickel slag promoted the occurrence of secondary hydration. Scanning electron micrograph showed that the high magnesium nickel slag could optimize the microstructure compaction of the hardened body. The pore structure analysis proves the filling effect of high magnesium nickel slag particles and refines the pores. The research results could provide technical support for the application of high magnesium nickel slag in cement.