区域注浆影响下煤层底板太原组灰岩水水文地球化学演化规律  

Hydrogeochemical evolution law of Taiyuan Formation limestone water under coal seam floor caused by the influence of regional grouting

作　　者：郭艳[1,2,3] 桂和荣 魏久传[3] 庞迎春 胡满聪 郭祥东 洪荒[5] 聂锋[4] 崔亚利[5] 叶爽[5] GUO Yan;GUI Herong;WEI Jiuchuan;PANG Yingchun;HU Mancong;GUO Xiangdong;HONG Huang;NIE Feng;CUI Yali;YE Shuang(National Engineering Research Center of Coal Mine Water Hazard Controlling,Suzhou University,Suzhou 234000,China;Key Laboratory of Mine Water Resource Utilization of Anhui Higher Education Institutes,Suzhou University,Suzhou 234000,China;College of Earth Science and Engineering,Shandong University of Science and Technology,Qingdao 266590,China;Huaibei Mining Co.,Ltd.,Suzhou 235000,China;Hengyuan Coalmine of Wanbei Coal-Electricity Group Co.,Ltd.,Suzhou 234000,China)

机构地区：[1]国家煤矿水害防治工程技术研究中心,宿州学院,安徽宿州234000 [2]矿井水资源化利用安徽普通高校重点实验室宿州学院,安徽宿州234000 [3]山东科技大学地球科学与工程学院,山东青岛266590 [4]淮北矿业股份有限公司,安徽淮北235000 [5]安徽恒源煤电股份有限公司煤矿,安徽宿州234000

出　　处：《煤炭学报》2023年第8期3204-3217,共14页Journal of China Coal Society

基　　金：安徽省高校优秀科研创新团队资助项目(2022AH010081);安徽省公益性地质资助项目(2023-g-1-11);安徽省自然科学基金青年资助项目(2008085QD175)。

摘　　要：淮北煤田下组煤开采,主要威胁水源是煤层底板灰岩水(包括石炭系太原组及奥陶系灰岩水),淹井事故时有发生。针对底板灰岩水害治理,目前多采用地面定向钻高压注浆技术,对煤层底板太原组第3层薄层灰岩(简称“三灰”)进行区域性加固改造,以封堵三灰岩溶裂隙并阻断穿过三灰的垂向导水通道。但大规模高压注浆工程的实施,受注含水层地下水流场会受到干扰,在大量浆液析出水的耦合作用下,地下水化学场必然会受到严重扰动。以淮北煤田桃园煤矿太原组灰岩含水层(简称“太灰水”)为研究对象,基于常量组分监测数据统计、Piper图、离子组合比及饱和指数分析,开展了区域注浆前-注浆期间-注浆结束后(即区域注浆前-中-后“三时段”)太灰水水文地球化学演化规律研究。结果表明:(1)三时段太灰水中Na^(+)+K^(+)、HCO_(3)^(-)、Cl^(−)先减小后增大,Ca2+、SO_(4)^(2-)和pH先增大后减小,Mg2+、TDS则整体减小。注浆治理区域Ca2+、SO_(4)^(2-)相对较高,碱度较大,而Na^(+)+K^(+)、HCO_(3)^(-)含量相对较低。注浆前以SO_(4)·Cl^(−)Na和SO_(4)·Cl^(−)Na·Ca(混合型)为主,区域注浆“中-后”时段,太灰水则以SO_(4)·Cl^(−)Na·Ca和SO_(4)·Cl^(−)Na型居多,混合型水占比增大。(2)注浆期间,太灰水中碳酸盐、硫酸盐溶解作用、脱硫酸作用和阳离子交换作用减弱,方解石、白云石的溶解作用增强,同时浆液析出水的混合影响作用明显。注浆结束后,碳酸盐、硫酸盐溶解作用、脱硫酸作用和阳离子交换作用逐渐增强,方解石、白云石的溶解作用逐渐减弱,浆液析出水的混合影响作用减弱。注浆结束1 a后水化学作用逐渐向注浆前状态恢复,但仍未恢复至注浆前状态,可知区域注浆治理对太灰水化学场扰动影响比较明显。(3)太灰水中白云石、方解石饱和指数较大,多呈现沉淀状态;石膏、岩盐饱和指数较小,多�The main threat source of coal mining in the lower formation of Huaibei Coalfield is limestone water from the coal seam floor(including the Carboniferous Taiyuan Formation and the Ordovician limestone water),and some well flooding accidents occur from time to time.For the control of water disaster in the limestone floor,at present,the ground directional drilling high-pressure grouting technology is mostly used for carrying out the regional reinforcement and re-construction of the third layer of thin limestone(referred to as“three ashes”)in the Taiyuan Formation of the coal seam floor.Therefore,it seals the karst cracks of the three ashes and blocks the vertical water channel passing through the three ashes.However,with the implementation of large-scale high-pressure grouting project,the groundwater flow field in the injected aquifer will be disturbed.Because of the coupling effect of a large amount of slurry water,the groundwater chem-ical field will inevitably be seriously disturbed.Taking the limestone aquifer of the Taiyuan Formation(hereinafter re-ferred to as“Taihui water”)in the Taoyuan Coalmine of the Huaibei Coalfield as the research object,based on the con-stant component monitoring data statistics,Piper diagram,ion combination ratio,and saturation index analysis,this paper studies the hydrogeochemical evolution law of the Taihui water before grouting,during grouting and after grouting(i.e.“three periods before,during and after regional grouting”).The results show that①in the three periods,Na^(+)+K^(+),HCO_(3)^(−),Cl^(−)in the Taihui water first decrease and then increase.Ca^(2+),SO_(4)^(2-)and pH values first increase and then decrease,while Mg2+,TDS decrease as a whole.In the grouting control area,Ca^(2+)and SO_(4)^(2-)are relatively high and alkalinity is relatively high,while Na^(+)+K^(+)and HCO_(3)^(−)are relatively low.Before grouting,SO_(4)·Cl^(−)Na and SO_(4)·Cl^(−)Na·Ca(mixed type)are the main types.Since regional grouting,SO_(4)·Cl^(−)Na·Ca and SO_(4)·Cl^(−)Na

关 键 词：区域注浆扰动 太灰水 水岩作用 淮北煤田 

分 类 号：P641[天文地球—地质矿产勘探]