煤炭资源开采过程中常伴随着大量矸石的排放并堆积至地表，不仅占用大量土地资源，同时极易引起矿区土壤、水体、农田及大气的污染问题，现阶段随着煤炭行业逐渐向绿色低碳转型，矸石的地面处理与排放受到严格控制，短壁块段式充填采煤技术作为一种环境友好型采煤技术，可从源头解决矸石堆积造成的环境问题，但矸石被充入采空区后，受到矿井水的长期浸泡，内部重金属离子逐渐释放，并向底板下方不断迁移，对矿区水资源造成潜在污染影响。为此，本文结合短壁块段式充填采煤技术，采用实验室试验、数值模拟计算、理论分析以及现场调研等多种手段相结合的方法，对短壁块段式充填采煤矸石充填体重金属离子释放-迁移规律及控制进行系统地研究。主要研究成果如下：

（1）确定了矸石充填体重金属离子对矿区水资源造成污染的敏感性因素，开展了矸石充填材料重金属离子赋存形态的试验研究，筛选出了矸石充填材料内部污染性较强的重金属离子，分别为Hg⁺、Al³⁺、Cd²⁺、Mn²⁺、Be²⁺，并采用静态浸泡的方法揭示了不同矸石粒径、粒径级配、充实率以及矿井水pH值下矸石充填材料重金属离子的释放规律。

（2）基于采空区矸石充填体所处环境，建立了矸石充填体重金属离子迁移过程中考虑损伤的底板渗流-应力-浓度耦合数学模型，推导了重金属离子迁移过程中的渗流场、应力场、浓度场以及损伤作用控制方程，并从两个角度对数学模型的准确性和可靠性进行误差性分析。

（3）运用COMSOL Multiphysics数值软件，建立了采空区矸石充填体重金属离子“下行”迁移数值模型，分析了不同矸石粒径、粒径级配、充实率、矿井水pH值、重金属离子类型、底板岩性以及底板裂隙深度对矸石充填体重金属离子迁移的影响，揭示了采空区矸石充填体重金属离子释放-迁移内在驱动行为，发现矸石充填体与矿井水发生长期作用后，内部重金属离子不断释放，并以矿井水为载体，以重力势能和水头压力为驱动，沿着底板岩层的孔隙、裂隙通道不断向下迁移。

（4）基于对采空区矸石充填体重金属离子释放-迁移行为的研究，从重金属离子释放控制和迁移控制两个角度出发，总结了矿区水资源污染防治调控方法，并以充实率作为关键点，提出了基于矿区水资源损伤防治下的充实率工程设计方法，为成功解决采空区矸石充填体造成的矿区水资源污染问题提供了科学依据。

The exploitation of coal resources often accompanies the discharge and accumulation of a large amount of gangue on the surface, which not only occupies a large amount of land resources, but also easily causes pollution problems in soil, water bodies, farmland, and the atmosphere of mining areas. At present, as the coal industry gradually transitioned towards green and low-carbon development, the surface treatment and emissions of waste gangue were strictly controlled. As an environmentally friendly coal mining technology, the short-wall block backfill mining technology can solve the environmental problems caused by gangue accumulation from the source. However, upon backfill gangue into the mined-out areas, and subsequent long-term immersion in mine water, these heavy metal ions gradually released, continuously migrating towards the bottom plate, causing potential pollution to the water resources in the mining area. Therefore, the paper combined the short-wall block backfill mining technology and employed a method that integrated laboratory experiments, numerical simulation calculations, theoretical analysis, and field surveys to systematically study the release-migration law and control of heavy metal ions in gangue backfill bodies. The main research results were as follows:

(1) Determine the sensitivity of metal ions to mining water pollution in gangue backfill bodies and conducted experimental studies on the occurrence forms of heavy metal ions in gangue backfill materials. The heavy metal ions with strong internal pollution in gangue backfill materials were screened, which were Hg⁺、Al³⁺、Cd²⁺、Mn²⁺ and Be²⁺. The release patterns of heavy metal ions in gangue backfill materials were revealed under different gangue particle sizes, particle size distributions, backfill ratios, and mine water pH values using the static immersion method.

(2) Based on the environment of gangue backfill in the mined-out areas, the mathematical model of seepage-stress-concentration coupling of the bottom fissure rock mass in the process of metal ion migration was established, and the seepage field, stress field, concentration field and damage control equation in the process of heavy metal ion migration were derived, and the accuracy and reliability of the mathematical model were analyzed from two angles.

(3) Utilized COMSOL Multiphysics numerical software, the weight of gangue backfill metal ion "downward" migration numerical model were established. The effects of different gangue particle sizes, particle size distributions, backfill ratios, mine water pH values, types of heavy metal ions, bottom plate rock types, and bottom plate fracture depths on the migration of heavy metal ions in gangue backfill bodies were analyzed, the inherent driving behavior of heavy metal ions release and migration in gangue backfill bodies were revealed. It was found that after the long-term interaction between the gangue backfill body and the mine water, the internal heavy metal ions were continuously released, and the mine water was used as the carrier. Driven by gravity potential energy and water head pressure, it migrated downward along the pores and fracture channels of the floor rock layer.

(4) Based on the study of heavy metal ions release and migration behavior in gangue backfill bodies, summarized methods for controlling water resource pollution in the mining area from the perspectives of heavy metal ions release control and migration control. With backfill ratio as a key point, a backfill ratio engineering design method based on the prevention and control of water resource damage in the mining area was proposed, providing a scientific basis for effectively solving water resource pollution caused by gangue backfill bodies.

[1]郭文兵, 赵高博, 杨伟强, 等. 高耸构筑物采动变形特征与地基精准注浆加固机理[J]. 煤炭学报, 2022, 47(5): 1908-1920.

[2]Zhang Jujiang, Feng Guorui, Zhang Min, et al. Residual coal exploitation and its impact on sustainable development of the coal industry in China[J]. Energy Policy, 2016, 96: 534-541.

[3]张彦禄, 王步康, 张小峰, 等. 我国连续采煤机短壁机械化开采技术发展40a与展望[J]. 煤炭学报, 2021, 46(1): 86-99.

[4]曹鑫. 唐口煤矿深部充填开采地表变形规律研究[D]. 徐州: 中国矿业大学, 2019.

[5]钱鸣高, 石平五, 许家林. 矿山压力与岩层控制[M]. 徐州: 中国矿业大学出版社, 2010.

[6]高保彬, 刘云鹏,潘家宇,等. 水体下采煤中导水裂隙带高度的探测与分析[J]. 岩石力学与工程学报, 2014, 33(S1): 3384-3390.

[7]Wu Qiang, Shen Jianjun, Liu Weitao, et al. A RBFNN-based method for the prediction of the developed height of a water-conductive fractured zone for fully mechanized mining with sublevel caving[J]. Arabian Journal of Geosciences, 2017, 10(7): 1-9.

[8]王玉涛. 煤矸石固废无害化处置与资源化综合利用现状与展望[J]. 煤田地质与勘探, 2022, 50(10): 54-66.

[9]Li Jiayan, Wang Jinman. Comprehensive utilization and environmental risks of coal gangue: A review[J]. Journal of Cleaner Production, 2019, 239: 117946.

[10]Xue Qiang, Lu Haijun, Zgao Ying, et al. The metal ions release and microstructure of coal gangue corroded by acid-based chemical solution[J]. Environmental Earth Sciences, 2014, 71(7): 3235-3244.

[11]邓军, 李贝, 肖旸, 等. 基于热重-傅里叶红外光谱联用的煤矸石自燃特性及微观表征[J]. 西安科技大学学报, 2017, 37(1): 1-6.

[12]卢晋波. 东曲煤矿井下矸石充填工艺及其经济效益分析[J]. 山西冶金, 2018, 41(6): 137-138+165.

[13]张云, 曹胜根, 来兴平, 等. 短壁块段式充填采煤覆岩导水裂隙发育机理及控制研究[J]. 采矿与安全工程学报, 2019, 36(6): 1086-1092.

[14]周茂普. 连续采煤机块段式开采工艺与围岩控制技术研究[D]. 徐州: 中国矿业大学, 2014.

[15]曹胜根, 曹洋, 姜海军. 块段式开采区段煤柱突变失稳机理研究[J]. 采矿与安全工程学报, 2014, 31(6): 907-913.

[16]张云. 西部矿区短壁块段式采煤覆岩导水裂隙发育机理及控制技术研究[D]. 徐州: 中国矿业大学, 2019.

[17]郭广礼, 李怀展, 查剑锋, 等. 平原煤粮主产复合区煤矿开采和耕地保护协同发展研究现状及对策[J]. 煤炭科学技术, 2023, 51(1): 416-426.

[18]庞绪峰, 蔡来生, 王忠武, 等. 急倾斜煤层充填开采覆岩运移规律模拟试验研究[J]. 煤炭工程, 2014, 46(10): 149-153.

[19]戴华阳, 郭俊廷, 阎跃观, 等. “采-充-留”协调开采技术原理与应用[J]. 煤炭学报, 2014, 39(8): 1602-1610.

[20]刘建功, 赵家巍, 李蒙蒙, 等. 煤矿充填开采连续曲形梁形成与岩层控制理论[J]. 煤炭学报, 2016, 41(2): 383-391.

[21]王磊, 张鲜妮, 郭广礼, 等. 固体密实充填开采地表沉陷预计模型研究[J]. 岩土力学, 2014, 35(7): 1973-1978.

[22]贾林刚, 张华兴, 刘鹏亮. 充填步距对地表移动变形特征的控制影响[J]. 中国矿业大学学报, 2022, 51(4): 642-650.

[23]张升, 张吉雄, 闫浩, 等. 极近距离煤层固体充填充实率协同控制覆岩运移规律研究[J]. 采矿与安全工程学报, 2019, 36(4): 712-718.

[24]赵斌臣, 郭广礼, 赵军. 固体充填开采沉陷控制影响因素数值模拟研究[J]. 煤炭技术, 2016, 35(6): 37-39.

[25]郭庆彪, 郭广礼, 吕鑫, 等. 基于连续-离散介质耦合的密实充填开采地表沉陷预测模型[J]. 中南大学学报(自然科学版), 2017, 48(9): 2491-2497.

[26]常庆粮. 膏体充填控制覆岩变形与地表沉陷的理论研究与实践[D]. 徐州: 中国矿业大学, 2009.

[27]Li Huaizhan, Guangli Guo. Surface subsidence control mechanism and effect evaluation of gangue-backfilling mining: A Case Study in China[J]. Geofluids, 2018, 2018: 1-9.

[28]Guo Kaikai, Guo Guangli, Li Huaizhan, et al. Strata movement and surface subsidence prediction model of deep backfilling mining[J]. Energy Sources Part A-recovery Utilization and Environmental Effects, 2020: 1-15.

[29]李猛, 张吉雄, 邓雪杰, 等. 含水层下固体充填保水开采方法与应用[J]. 煤炭学报, 2017, 42(1): 127-133．

[30]张吉雄, 李猛, 邓雪杰, 等. 含水层下矸石充填提高开采上限方法与应用[J]. 采矿与安全工程学报, 2014, 31(2): 220-225.

[31]马立强, 王烁康, 余伊河, 等. 壁式连采连充保水采煤技术及实践[J]. 采矿与安全工程学报, 2021, 38(5): 902-910.

[32]Zhang Jixiong, Sun Qiang, Li Meng, et al. The mining-induced seepage effect and reconstruction of key aquiclude strata during backfill mining[J]. Mine Water Environ, 2019, 38: 590-601.

[33]郭文兵, 杨达明, 谭毅, 等. 薄基岩厚松散层下充填保水开采安全性分析[J]. 煤炭学报. 2017. 42(1): 106-111.

[34]黄庆享, 张文忠. 浅埋煤层条带充填隔水岩组力学模型分析[J]. 煤炭学报, 2015, 40(5): 973-978.

[35]Carvalho P C S , Neiva A M R , Silva M M V G ,et al.Metal and metalloid leaching from tailings into streamwater and sediments in the old Ag–Pb–Zn Terramonte mine, northern Portugal[J].Environmental Earth Sciences, 2014, 71(5): 2029-2041.

[36]Aparajita Bhattacharya, Joyanto Routh, Gunnar Jacks, et al. Environmental assessment of abandoned mine tailings in Adak, Vasterbotten district (northern Sweden)[J], Applied Geochemistry, 2006, 21(10): 1760-1780.

[37]Komnitsas K , Paspaliaris I , Zilberchmidt M ,et al.Environmental impacts at coal waste disposal sites-Efficiency of desulfurization technologies[J]. Global Nest, 2001, 3(2): 109-116.

[38]I Mascaro, M Benvenuti, F Corsini, et al. Mine wastes at the polymetallic deposit of Fenice Capanne[J]. Mineralogy, Geochemistry, and Environmental Impact. Env Geol, 2001, 41: 417-429.

[39]张锂, 韩国才, 陈慧, 等. 黄土高原煤矿区煤矸石中重金属对土壤污染的研究[J] . 煤炭学报, 2008, 33(10): 1141-1146.

[40]刘亚丽. 煤矸石淋溶液对周围地下水环境的影响分析[J]. 山西科技, 2018, 33(3): 76-80.

[41]李绪萍, 刘艳青, 张靖. 等. 中高硫煤矸石自燃阶段划分与气体析出规律相关性分析[J]. 煤炭科学技术, 2023, 51(S1): 141-149.

[42]王兴明, 张瑞良, 王运敏, 等. 淮南某煤矿邻近农田土壤中重金属的生态风险研究[J]. 生态环境学报, 2016, 25(5): 877-884.

[43]顾霖骏, 申艳军, 王念秦, 等. 煤矸石堆积区土壤重金属潜在危害评价及污染特征[J]. 西安科技大学学报, 2022, 42(5): 942-949.

[44]尚誉, 桑楠. 煤矸石堆积区周边土壤重金属污染特征与植物毒性[J]. 环境科学, 2022, 43(7): 3773-3780.

[45]秦胜, 田莉雅, 张剑. 兖州矿区矸石山与周围土壤中微量元素形态分析[J]. 中国煤炭, 2010, 36(10): 125-127+140..

[46]康得军, 吕茳芏, 脱向银, 等. 煤矸石山覆土体系重金属污染特征及生态风险评价[J]. 环境工程, 2022, 40(9): 158-166.

[47]李旭华, 王心义, 杨建. 焦作矿区煤矸石山周围土壤和玉米作物重金属污染研究[J]. 环境保护科学, 2009, 35(2): 66-69.

[48]张永康, 曹耀华, 冯乃琦, 等. 某废弃煤矿区土壤重金属污染风险评价[J]. 煤炭学报, 2023.

[49]陈昌东, 张安宁, 腊明, 等. 平顶山矿区矸石山周边土壤重金属污染及优势植物富集特征[J]. 生态环境学报, 2019, 28(6): 1216-1223.

[50]丛鑫, 雷旭涛, 付玲, 等. 海州煤矿矸石山周边土壤重金属污染特征及生态风险评价[J]. 地球与环境, 2017, 45(3): 329-335.

[51]Huang Yanli, Li Junmeng, Song Tianqi, et al. Microstructure of coal gangue and precipitation of heavy metal elements[J]. Journal of Spectroscopy, 2017: 3128549.

[52]Kovács E, Dubbin W E, Tamás J. Influence of hydrology on heavy metal speciation and mobility in a Pb–Zn mine tailing[J]. Environmental Pollution, 2006, 141(2): 310-320.

[53]Nicholson R V, Rinker M J, Acott G, et al. Integration of field data and a geochemical transport model to assess mitigation strategies for an acid-generating mine rock pile at a uranium mine[J]. 2003.

[54]Yang Deli, Li Junmeng, Huang Yanli, et al. Research on migration law of mn in mudstone floor in the goaf under coupling conditions of seepage and stress[J]. Polish Journal of Environmental Studies, 2019, 29(1): 939-950.

[55]Xu Dongjing, Shi Longqing, Qu Xingyue, et al. Leaching behavior of heavy metals from the coal gangue under the impact of site ordovician limestone karst water from closed shandong coal mines, North China[J]. Energy & Fuels, 2019, 33(10): 10016-10028.

[56]Qi Wenyue, Huang Yanli, He Hu, et al. Potential pollution of groundwater by dissolution and release of contaminants due to using gangue for backfilling[J]. International Journal of Mine Water, 2019, 38(2):281-293.

[57]Qi Wenyue, Zhang Jixiong, Zhang Qiang. Compression of aggregates of acid-leached coal gangues: implications for coal mine backfill[J]. Advances in Materials Science and Engineering, 2018, 2018(4): 1-3.

[58]Zhang Hongjian, Ouyang Sailan. Release characteristics of heavy metals from coal gangue under simulation leaching conditions[J]. Energy Exploration & Exploitation, 2014, 32(2): 413-422.

[59]周亮亮. 淋滤作用下碱性煤矸石重金属污染物迁移规律研究[D]. 阜新: 辽宁工程技术大学, 2022.

[60]李巍. 煤矿地下水库破碎矸石淋滤条件下离子动态吸附特性研究[D]. 徐州: 中国矿业大学, 2021.

[61]毕卫华, 王彦君, 刘恒凤, 等. 恒源矿矸石堆积区重金属污染风险及其迁移机制[J]. 环境科学与技术, 2021, 44(S2):331-337.

[62]徐朝容. 矿区充填复垦物料中重金属元素释放-迁移研究[D]. 徐州: 中国矿业大学, 2020.

[63]狄军贞, 鲍斯航, 杨逾, 等. 粒径对煤矸石污染物溶解释放规律影响研究[J]. 煤炭科学技术, 2020, 48(4):178-184.

[64]赵洪宇, 李玉环, 宋强, 等. 煤矸石动态循环淋溶液的特性[J]. 环境工程学报, 2017, 11(2):1171-1177.

[65]刘玲, 刘海卿, 李喜林, 等. 铬渣堆场渗滤液对地下水污染的数值仿真[J]. 辽宁工程技术大学学报(自然科学版), 2017, 36(10): 1053-1058.

[66]中华人民共和国国家质量监督检验检疫总局. GB/T 14848-2017-地下水质量标准[S].北京：中国标准出版社，2017.

[67]徐心远. 煤矸石中重金属元素赋存形态及释出特征研究[D]. 焦作: 河南理工大学, 2015.

[68]姜利国. 煤矸石山中多组分溶质释放-迁移规律的研究[D]. 阜新: 辽宁工程技术大学， 2010.

[69]张肖萌, 郭巧玲, 杨云松, 等. 煤炭矿区排矸场表层土壤重金属污染研究[J]. 有色金属, 2023(10): 149-157.

[70]范春辉, 张颖超, 王家宏. 基于Tessier-AAS法的华中大农区污染红土Pb赋存形态非生物转化机制研究[J]. 光谱学与光谱分析, 2015, 35(2): 534-538.

[71]李娜, 夏瑜, 何绪文, 等. 基于Tessier法的土壤中不同形态镉的转化及其影响因素研究进展[J]. 土壤通报, 2021, 52(6): 1505-1512.

[72]孔国强. 破碎矸石侧限压缩过程的声发射特征研究[D]. 徐州: 中国矿业大学, 2019.

[73]李俊孟. 矸石固废充填材料承载压缩三维组构 时空演化及其透明化表征[D]. 徐州: 中国矿业大学, 2020.

[74]薛熠. 采动影响下损伤破裂煤岩体渗透性演化规律研究[D]. 徐州: 中国矿业大学, 2017.

[75]王振. 基于参数非均质性的重力坝渗流-应力-损伤耦合分析[D]. 天津: 天津大学, 2018.

[76]Fu Pengcheng, Johnson Scott M, Carrigan Charles R. An explicitly coupled hydro-geomechanical model for simulating hydraulic fracturing in arbitrary discrete fracture networks[J]. International Journal for Numerical and Analytical Methods in Geomechanics. 2013, 37(14): 2278–2300.

[77]Li Lei, Chen Jing, Huang Yong, et al. Experimental investigation and numerical simulation of contaminant migration in the compacted clay containing artificial fractures[J]. Environmental Earth Sciences. 75, 134.

[78]孙亚军, 陈歌, 徐智敏, 等. 我国煤矿区水环境现状及矿井水处理利用研究进展[J]. 煤炭学报, 2020, 45(1): 304-316.

[79]Kefeni Kebede K, Msagati Titus AM, Mamba Bhekie B. Acid mine drainage: Prevention, treatment options, and resource recovery: A review[J]. Journal of Cleaner Production, 2017, 151: 475-493.

[80]景兵. 龙泉矿高承压底板岩层中粘土水泥浆扩散特性与注浆改性技术研究[D]. 徐州: 中国矿业大学, 2021.

[81]王凡, 谌伦建, 徐冰, 等. 煤炭地下气化污染地下水的迁移与渗透反应墙净化数值模拟研究[J]. 煤炭学报, 2023, 48(4): 1697-1706.

杨茸茸, 周军, 吴雷, 等. 可渗透反应墙技术中反应介质的研究进展[J]. 中国环境科学, 2021, 41(10): 4579-4587.