级配和含盐度对钾长石质粉砂的静水沉降影响试验研究  

Experimental study on the effect of sediment composition and water salinity on settling processes of Potassium Feldspar silt in still water

作　　者：苏敏 唐弘楠 刘志成 姚鹏 SU Min;TANG Hong-nan;LIU Zhi-cheng;YAO Peng(State Key Laboratory of Hydrology,Water Resources and Hydraulic Engineering,Hohai University,Nanjing 210098,China;Key Laboratory of Ocean Space Resource Management Technology MNR,Hangzhou 310012,China;Jiangsu Key Laboratory of Coast Ocean Resources Development and Environment Security,Nanjing 210098,China;College of Harbor,Coastal and Offshore Engineering,Hohai University,Nanjing 210098,China;State Key Laboratory of Coastal and Offshore Engineering,Dalian University of Technology,Dalian 116024,China)

机构地区：[1]河海大学水文水资源与水利工程科学国家重点实验室,江苏南京210098 [2]自然资源部海洋空间资源管理技术重点实验室,浙江杭州310012 [3]江苏省海岸海洋资源开发与环境安全重点实验室,江苏南京210098 [4]河海大学港口海岸与近海工程学院,江苏南京210098 [5]大连理工大学海岸和近海工程国家重点实验室,辽宁大连116024

出　　处：《泥沙研究》2024年第3期25-32,共8页Journal of Sediment Research

基　　金：国家重点研发计划课题(2022YFC3106201);中央高校基本科研业务费项目(B230201046);国家自然科学基金项目(51809296,51709288);大连理工大学海岸和近海工程国家重点实验室开放基金项目(LP2207);自然资源部海洋空间资源管理技术重点实验室开放基金项目(KF-2023-106)。

摘　　要：细颗粒泥沙的沉降过程中易发生絮凝现象,絮凝是否发生受到粒径、盐度、级配、矿物组成等多因素的影响。以钾长石为例,研究粒径、级配和含盐度对钾长石质粉砂静水沉降的影响。试验研究发现,清水中的钾长石质粉砂絮凝临界粒径约为30μm,盐水可将絮凝粒径上限提高至50μm。絮凝最优含盐度为15 ppt,但不同粒径的絮凝指标有差异,盐度对粒径小于50μm的细颗粒影响更大,絮凝更显著,50μm以上的粗颗粒基本不发生絮凝。就絮凝结构而言,粗颗粒的钾长石质粉砂以单颗粒沉降为主,细颗粒则表现为颗粒间聚并絮凝。Fine-grained sediment is prone to flocculation during settling process.The occurrence of flocculation can be influenced by multiple factors such as particle size,salinity,particle size grading,mineral composition,water temperature,and sediment concentration.The silt with potassium feldspar is taken as an example,an experimental study has been conducted to investigate the effects of sediment particle size and its gradation,and salinity on settling process in hydrostatic water.The results show that the critical size for flocculation of potassium feldspar silt in fresh water is about 30μm and it can reach to 50μm in saline water.The optimal salinity for flocculation is 15 ppt,but the flocculation index varies among different sediment particle size:Salinity has a greater impact on fine sediment with particle size less than 50μm,and the flocculation is more significant.Coarse particles above 50μm do not undergo flocculation.The coarse sediment is generally dominated by single-particle settling,while fine sediment is flocculated with particle aggregation.

关 键 词：钾长石 粉砂 静水沉降 含盐度 级配 絮凝 

分 类 号：TV142.1[水利工程—水力学及河流动力学]