底泥扰动悬浮除藻技术

发布时间：2018-03-24 05:08

本文选题：底泥　切入点：扰动　出处：《苏州科技学院》2015年硕士论文

【摘要】：底泥扰动可以去除富营养化河道中的藻类,利于藻细胞被悬浮颗粒物打碎并在底泥自然沉降中被吸附。但对于底泥扰动除藻效果的相关研究甚少。因而研究底泥扰动悬浮除藻效果及机制,对解决水体富营养化问题具有重要意义。本文探讨了三方面,一、不同扰动参数下上覆水中藻类的去除效果及机制；二、底泥扰动对上覆水中不同种属藻类的去除效果；三、底泥扰动和混凝联用实验的除藻效果,为底泥扰动作为一项新的除藻技术供一定的基础理论研究。本研究参考粘土除藻、混凝沉淀除藻和水动力学条件对藻类生长影响等研究成果,对底泥扰动这种新方法除藻效果进行初步探索研究。结果表明,底泥扰动可以提高叶绿素a的去除率,第一次扰动后,叶绿素a去除率平均达到最大(65%),此后,每次扰动后叶绿素a的下降幅度均低于第一次扰动。增加扰动强度、扰动时间,可以提高第一次扰动后的藻类去除率。高频率扰动下,藻类的去除率相对稳定。同时,底泥扰动能够有效抑制上覆水中藻的光合作用活性,显著低于对照实验；底泥扰动对溶解性磷酸盐(DIP)和氨氮也有一定的去除效果。通过对扰动前后藻类的细胞形态的镜检分析,可以初步得出底泥扰动的除藻机理：底泥扰动可以增加水中悬浮物的数量和运动速率,一方面通过机械扰动打碎并致死藻类,改变藻细胞表面的物理、化学性质,使其无法在表层聚集,从而控制其进一步增殖。另一方面破碎后的细胞残骸,由于体积的明显减少,便于底泥在自然沉降中对上覆水中藻类的静电吸附。对本实验水样中的藻种分析表明,原水中藻类主要以蓝藻和绿藻为主,硅藻含量较低。底泥扰动可以完全去除水体中的硅藻和大部分蓝藻和绿藻。同时,底泥扰动对水中各藻属均有很好的抑制胁迫作用,尤其蓝藻和硅藻光合作用活性消失,藻细胞几乎全部死亡。底泥扰动预处里和混凝联用工艺对叶绿素a的去除率平均达到91.82%,明显高于无底泥预处理(73.90%)。与未扰动预处理相对比,扰动预处理后,混凝工艺对叶绿素a去除率提高了10%。这说明对于除藻而言底泥扰动与混凝工艺之间具有协同作用。
[Abstract]:Sediment disturbances remove algae from eutrophication channels, It is beneficial for algae cells to be smashed by suspended particles and adsorbed in the natural deposition of sediment. However, there is little research on the effect of sediment disturbance on algae removal. Therefore, the effect and mechanism of suspended algal removal by sediment disturbance are studied. It is of great significance to solve the problem of eutrophication of water body. This paper discusses three aspects: first, the removal effect and mechanism of algae in overlying water under different disturbance parameters; second, the removal effect of sediment disturbance on algae belonging to different species in overlying water; The algal removal effect of sediment disturbance and coagulation experiment provides a certain basic theoretical research for sediment disturbance as a new algal removal technology. The effect of sediment disturbance on algae removal was studied. The results showed that sediment disturbance could improve the removal rate of chlorophyll a. After the first disturbance, the average removal rate of chlorophyll a reached to the maximum of 65%. Thereafter, the decrease of chlorophyll a after each disturbance was lower than that of the first disturbance. Under high frequency disturbance, the algae removal rate was relatively stable. At the same time, the sediment disturbance could effectively inhibit the photosynthesis activity of algae in the overlying water, which was significantly lower than that in the control experiment. Sediment disturbance can also remove dissolved phosphate (DIPs) and ammonia nitrogen. The microscopical analysis of algae cell morphology before and after disturbance, The mechanism of algal removal from sediment disturbance can be preliminarily obtained: sediment disturbance can increase the quantity and movement rate of suspended matter in water. On the one hand, the physical and chemical properties of algae cell surface can be changed by breaking and killing algae by mechanical disturbance. Which prevents it from gathering on the surface, thus controlling its further proliferation. On the other hand, the broken remains of the cells, due to a significant reduction in volume, It is convenient for the sediment to adsorb algae in the overlying water by static electricity. The analysis of algae species in the experimental water shows that the algae in the raw water are mainly cyanobacteria and green algae. The sediment disturbance can completely remove diatoms and most cyanobacteria and green algae from the water. At the same time, the sediment disturbance can inhibit the stress of all algae in water, especially the photosynthesis activity of cyanobacteria and diatoms disappeared. Almost all algal cells died. The average removal rate of chlorophyll a was 91.82, which was significantly higher than that of no sediment pretreatment (73.90g). Compared with undisturbed pretreatment, the removal rate of chlorophyll a was significantly higher than that of undisturbed pretreatment, after disturbance pretreatment, the removal rate of chlorophyll a was significantly higher than that of undisturbed pretreatment. The removal rate of chlorophyll a was increased by 10% by coagulation process, which indicated that there was a synergistic effect between sediment disturbance and coagulation process for algae removal.
【学位授予单位】：苏州科技学院
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X52

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