盐度和腐殖酸共同作用下的长江口泥沙絮凝过程研究   总被引：5，自引：2，他引：3       下载免费PDF全文

刘启贞  李九发  徐灿华  戴志军  李道季 《海洋学报》2008,30(3):140-147

长江河口有机质含量丰富,盐度变化较大,因此研究长江河口以细颗粒泥沙为主的多因子共同作用下的絮凝有助于了解最大浑浊带的形成机制.通过实验研究盐度和腐殖酸共同作用对长江口细颗粒泥沙浊度变化影响的过程,从浊度相对变化率、絮团粒径和电位变化三方面综合分析了其絮凝机理,并且对絮凝体进行了红外和电镜分析,探讨了絮凝体的微观结构.结果表明:(1)随着盐度增大细颗粒泥沙浊度相对变化率逐渐增大,粒径增大,而电位绝对值变小;(2)随着腐殖酸浓度增大细颗粒泥沙浊度相对变化率先略有升高后迅速降低,粒径增大,电位绝对值增大;(3)微观结构的分析表明腐殖酸是以腐殖酸盐的形式包覆在泥沙表面,同时也验证了河口中C-P-OM(C代表黏土,P代表阳离子,OM代表有机化合物)的泥沙絮凝模式.  相似文献   

云南腾冲科学钻探废弃钻井液固化处理技术研究     

卢予北  范晓远  吴烨  李丹丹 《探矿工程》2013,40(8):14-17

根据云南腾冲科学钻探废弃钻井液的特点,确定了先絮凝破胶再固化的技术路线,筛选出絮凝破胶预处理及固化的最优配方。实验结果表明,固化效果良好,经絮凝沉降后分离出的废水、固化物浸出液污染物含量均达到污水综合排放一级标准。  相似文献   

Settling velocities of mud aggregates in the oosterschelde tidal basin (The Netherlands), determined by a submersible video system     

Wilfried B.M. ten Brinke 《Estuarine, Coastal and Shelf Science》1994,39(6)

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枯季珠江河口悬浮泥沙絮凝沉降特征的观测与分析   总被引：2，自引：0，他引：2  

夏小明  李炎  杨辉  吴超羽 《海洋学研究》2006,24(1):6-18

2000年1月,利用L ISST-ST现场激光粒度沉速仪,对珠江河口悬浮泥沙的现场粒级与沉速特征进行观测和分析,结果表明:珠江河口悬浮泥沙絮凝沉降特征具有复杂的时空变化,悬浮泥沙颗粒现场中值粒径为10~96μm,各粒级颗粒的现场中值沉速为0.001~0.02 cm/s,并可用关系式iω=k.din(0.29相似文献   

In situ video and diffraction analysis of marine particles     

Michel Lunven  P. Gentien  K. Kononen  E. Le Gall  M. M. Danilou 《Estuarine, Coastal and Shelf Science》2003,57(5-6):1127-1137

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Investigation on Settling Characteristics of Floes in the Changjiang Estuary, China     

Li Yan  Wang Yaqin LinYian Associate Professor  Second Institute of Oceanography  State Oceanic Administration  Hangzhou  Senior Engineer  Second Institute of Oceanography  State Oceanic Administration  Hangzhou 《中国海洋工程》1995,(3)

- Settling characteristics of floes, including relative settling velocity, relative flocculation coefficient and flocculation exponent, are obtained by the suspended load equations for different size fractions. Data of the Changjiang Estuary suggest that level of flocculation changes from river section, river mouth (turbidity maximum) to offshore area in sequence of low, very high and high. The settling characteristics of floes reflected by in situ estimation performs a similar feature as that obtained from still water experiment.  相似文献   

Rethinking what constitutes suspended sediment     

Ian G. Droppo 《水文研究》2001,15(9):1551-1564

Although cohesive suspended sediment is now known to be transported primarily as flocculated material, there is still a misconception of what constitutes suspended sediment. Flocs represent a complex matrix of microbial communities, organic particles (e.g. detritus, extracellular polymers and cellular debris), inorganic particles (e.g. clays and silts) and substantial interfloc spaces (pores), which allow for the retention or flow through of water. Flocculation results in significant alteration of the hydrodynamics of the constituent particles (by modifying their effective size, shape, density and porosity), thereby affecting the transport of sediment and associated contaminants. The composition and structure of a floc is in a continuous state of change as the medium in which it is transported provides the floc with further building materials, energy, nutrients and chemicals for biological growth, chemical reactions and morphological development. As such, a floc's physical (e.g. transport), chemical (e.g. contaminant adsorption) and biological (community development and contaminant biotransformation) behaviour are also in a continuous state of change, with concomitant effects on their aquatic environment as a whole. Although it is recognized that floc form will influence floc behaviour, there is still a basic lack of knowledge of the complex links between the structural components of a floc and how their individual properties and behaviours in combination with others will influence a floc's physical, chemical and biological behaviour. This paper provides a comprehensive conceptual model that links the many interrelated structural components of typical flocs and their interrelated behavioural aspects, in order to enhance our understanding of what constitutes suspended sediment. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

Are hydrodynamic shape effects important when modelling the formation of depositional remanent magnetization?     

D. Heslop 《Geophysical Journal International》2007,171(3):1029-1035

Recent conceptual models have attributed the weak depositional remanent magnetizations observed in natural sediments to flocculation processes in the water column. Magnetic particles included into flocs have not only to rotate themselves into alignment with the geomagnetic field but also the larger particles to which they are attached, making remanence acquisition an inefficient process. Alignment is hindered further when the magnetization vectors of the particles in any given floc partially cancel, reducing the overall magnetic torque. Existing numerical simulations of flocculation effects on depositional remanence formation have been limited to spherical bodies with translational and rotational motion acting independently of each other. In the case of non-spherical flocs, the translational and rotational motion are coupled and such bodies will describe a complex trajectory through the water column. Calculations will be presented that show the torque exerted on a non-spherical floc by the surrounding water can be orders of magnitude greater than the magnetic torque. Non-spherical flocs will, therefore, align less efficiently with the geomagnetic field and hydrodynamic effects may play an important role in controlling the magnitude of sedimentary remanence.  相似文献   

风浪扰动引起湖泊磷形态变化的模拟试验研究   总被引：8，自引：0，他引：8       下载免费PDF全文

高永霞  孙小静  张战平  朱广伟  逄勇 《水科学进展》2007,18(5):668-673

为了解一次完整的大风浪过程(包括风浪扰动及扰动后的静风期)水体中各形态磷的变化情况及其影响因素,进行了室内模拟风浪扰动的试验研究。结果显示大风浪扰动初期水体中悬浮物(SS)、总磷(TP)、颗粒态磷(PP)和溶解性总磷(DTP)的浓度大幅增加,扰动持续半天后水体SS、TP、PP的浓度均达到最大值,扰动停止后,至少需要10d时间水体中SS、TP、PP的浓度才能回复到扰动前水平;扰动期间水体DTP浓度居于高值,但风浪停止后立即降低;整个风浪过程水体中溶解性反应磷(SRP)浓度变化不大。试验表明,扰动初期沉积物中Fe、Mn结合态磷能快速释放到水体中,但随着扰动的持续,水体复氧,释放到水体中的溶解性活性磷又能与Fe、Mn结合随悬浮物沉降到水底。扰动期间及随后静置1d时间内,水体中悬浮颗粒物的中值粒径连续下降,意味着悬浮颗粒物对磷的吸附能力在不断增强。但水体静置较长时间后,扰动引起的悬浮物几乎全部沉降,絮凝等作用导致水体颗粒物粒度增大。本研究说明虽然大风浪扰动初期能引起浅水湖泊中颗粒态和溶解态营养盐浓度的迅速提高,能够为水华蓝藻的快速生长提供大量可直接利用或酶解的营养盐,但随着风浪扰动的持续,由于水体复氧、水中颗粒物粒度不断细化、颗粒物中的有机成分比例不断增高等,悬浮颗粒物对活性磷的吸附能力也相应提高,两种作用相互削减使得风浪扰动后期水体活性磷浓度的增幅并不明显。  相似文献   

C/B法城镇污水处理技术简介   总被引：1，自引：0，他引：1  

张生炎  扈胜禄  黄伟  王玉宾  孙伟 《矿产与地质》2003,17(1):78-81

目前我国城市污水处理普遍采用的工艺为普通活性污泥法、氧法沟法、SBR法及AB法等。这些工艺虽然运行稳定，达到可靠，但投资大、运行费用高。鉴于我国的经济发展水平与发达国家有较大的差距，污染治理的资金投入有限，提出必须研究适合我国国情的高效、低耗、低成本的城市污水处理技术。阐述了C/B法的C段和B段污水处理技术，指出由于该技术是化学强化处理技术与生物滤池技术的有机结合，综合了化学处理与生物处理技术的优点，具有可分阶段实施、投资省、运行费用低、占地少、有效去除磷、氨、氮等优点。  相似文献