摘要
为实现尾矿废物煤矸石的资源化利用,提升人工湿地填料对污水中氨氮、总氮(TN)、总磷(TP)及化学需氧量(COD)的去除率,以山丹县煤矸石为研究对象,采用盐酸(HCl)和氢氧化钠(NaOH)对其进行浸泡改性,结合BET,XRD,ICP-OES分别表征改性前后煤矸石的孔隙结构、矿物组成及元素分布;通过填料投加量实验及恒温振荡反应,采用标准方法测定污染物浓度,分析其除污性能及最佳条件。结果表明:未改性煤矸石对氨氮、TN、TP、COD去除率分别达48.90%,50.50%,66.99%,28.49%,初期因填料污染物溶出出现负去除率;3 mol/L的HCl改性效果最优,煤矸石比表面积、孔容较未改性分别提升6.9%,0.9%,矿物组成以黏土矿物和石英为主,元素仍以Si,Al为核心,对氨氮、TN、TP、COD去除率较未改性分别约提升21%,21%,8%,40%;高浓度NaOH使硅铝矿物水解生成可溶性硅酸盐堵塞孔隙,使污染物去除率下降。研究结果可为煤矸石高值化利用提供技术支撑,明确HCl改性提升吸附性能的机制,为人工湿地填料选择与改性工艺优化提供科学依据,对推进污水生态处理技术的可持续发展具有参考价值。
To realize the resource utilization of tailings waste coal gangue and improve the removal efficiency of ammonia nitrogen,total nitrogen(TN),total phosphorus(TP),and chemical oxygen demand(COD)in wastewater by constructed wetland fillers,this study took coal gangue from Shandan County as the research object.Hydrochloric acid(HCl)and sodium hydroxide(NaOH)were used for soaking modification,and BET,XRD,and ICP-OES methods were combined to characterize the pore structure,mineral composition,and element distribution of coal gangue before and after modification.Through filler dosage experiments and constant-temperature oscillation reactions,standard methods were adopted to determine pollutant concentrations,so as to analyze the pollutant removal performance and optimal conditions.The results showed that the removal rates of ammonia nitrogen,TN,TP,and COD by unmodified coal gangue reached 48.90%,50.50%,66.99%,and 28.49%,respectively,with negative removal rates appearing initially due to the leaching of pollutants from the filler.The modification with 3 mol/L HCl exhibited the optimal effect:compared with unmodified coal gangue,the specific surface area and pore volume of the modified coal gangue increased by 6.9% and 0.9%,respectively;the minerals were mainly clay minerals and quartz,and the core elements remained Si and Al;meanwhile,the removal rates of ammonia nitrogen,TN,TP,and COD were improved by 21%,21%,8%,and 40% compared with the unmodified group.High-concentration NaOH caused hydrolysis of silicoaluminum minerals,the formed soluble silicates blocked the pores and led to a decrease in pollutant removal efficiency.This study provides technical support for the high-value utilization of coal gangue,clarifies the mechanism by which HCl modification enhances adsorption performance,offers a scientific basis for the selection of constructed wetland fillers and the optimization of modification processes,and has reference value for the sustainable development of ecological wastewater treatment technologies.
出处
《环境保护与循环经济》
2026年第1期1-5,共5页
Environmental Protection and Circular Economy
基金
校企合作项目(尾矿废物与建筑垃圾及生物协同强化人工湿地养分去除的关键技术研究)
甘肃省联合科研基金项目(25JRRA1101)
甘肃省省级生态文明建设重点研发专项(25YFFA022)。
关键词
人工湿地填料
建筑废料
煤矸石
污水处理
artificial wetland fill material
construction waste
coal gangue
sewage treatment
