【作者】 董国日；

【导师】 王淀佐；

【作者基本信息】 中南大学 ， 矿物加工工程， 2007， 博士

【摘要】 本论文系统总结了SBRs类活性污泥工艺的发展历史、工艺类型以及其所涉及到的生物学理论。在此基础上通过实验系统研究了实现典型SBR工艺的自动化控制方式、典型SBR工艺处理有机污水的效果、典型SBR工艺处理有机污水过程中COD的浓度变化曲线以及SBR工艺耐冲击负荷能力，最后，系统地研究了重金属铬离子对于SBR工艺系统活性污泥的影响以及活性污泥对铬离子的吸收。现将研究结果总结如下：(1)利用PLC技术成功实现SBR工艺的自动化运行，并针对SBR工艺的运行特点总结了其PLC编程技巧，提出了循环可执行事件概念，并给出了一个循环可执行事件的编程模式。(2)利用SBR工艺处理有机污水均能取得良好效果。但SBR工艺处理高浓度有机污水和低浓度有机污水所应注意的事项不同：SBR工艺处理较低有机物浓度的污水时应注意提高污泥有机物负荷，可通过采用较高的排水比或缩短反应时间来实现，因为较低的有机负荷易造成活性污泥的内源氧化以及低有机物浓度下的丝状菌污泥膨胀，并且还有可能出现沉淀期缺氧反硝化产氮浮泥现象；SBR工艺处理高浓度有机物污水时，应注意降低污泥有机物负荷，宜采用较低的排水比或延长反应时间来实现，处理高浓度有机污水时易出现出水混浊及反应期缺氧丝状菌污泥膨胀现象。(3) SBR工艺系统具有很强的耐冲击负荷能力，其耐冲击负荷能力的大小一方面与活性污泥浓度有关，另一方面也与SBR工艺系统反应时间的长短有关。冲击负荷对SBR工艺所造成的影响，并不是破坏SBR工艺的活性污泥系统，而是有机物的冲击浓度超过了活性污泥的吸收能力。当恢复正常进水时，系统也将恢复正常。为说明SBR工艺的耐冲击负荷现象，本文提出了“贮存——利用(增殖)”模型，来解释SBR工艺的耐冲击负荷能力。(4)铬离子对活性污泥的毒性作用按照挥发性污泥(MLVSS)铬负荷可划分为四个范围：耐受性范围(0～～30mg／gmlvss)、崩溃范围(30～～65mg／gmlvss)、强絮凝范围(70～～100mg／gmlvss)、细胞分解范围(＞100mg／gmlvss)。活性污泥容积指数(SVI)的大小对此范围数值有影响。SVI数值低，则范围上下限数值向上偏移；SVI数值高，则范围上下限数值向下偏移。(5) SBR工艺系统活性污泥对铬离子的吸收即受铬负荷的影响也受污泥容积指数SVI的影响。铬负荷低于30mg／gMLVSS时对SBR工艺活性污泥吸收铬离子的影响不是很大，但会随污泥容积指数的增大而降低；铬负荷水平超过30mg／gMLVSS时，由于铬离子的毒性作用，SBR工艺系统活性污泥吸收铬离子的能力就会大大下降。(6)铬离子的毒性作用将导致活性污泥体积增大，而铬离子的絮凝作用则将导致活性污泥体积减小。二者的交叉作用，将随着铬负荷的增大(也即溶液中铬离子浓度的增大)而导致活性污泥30分钟污泥沉降体积呈现出波浪式变化。污泥容积指数(SVI)的大小影响铬离子对活性污泥30分钟污泥沉降体积大小的作用，使波浪式变化特征变得明显或不明显。(7)铬离子毒性作用、絮凝作用以及铬离子所造成的活性污泥比重上升都是影响活性污泥沉降过程的因素，同时活性污泥容积指数也明显得影响着铬离子对活性污泥沉降过程的作用。控制污泥沉降速度的因素与控制污泥最终沉降体积的因素并不一致。活性污泥沉降速度会因为铬离子浓度的增加而加快，但活性污泥的最终体积却是由铬离子对活性污泥菌群的毒性作用和絮凝作用共同作用的结果。(8) 120ml／gmlvss左右的污泥容积指数的活性污泥比较特殊。在此容积指数随近的活性污泥，随着铬负荷水平的升高，会发生逆膨胀现象，也即在低铬负荷影响下，活性污泥的沉降速度加快，而在高铬负荷下，却发生活性污泥体积比对照系统体积变大，活性污泥沉降速度变慢的情况，当然，这是在本论文实验的铬负荷范围内。更多还原

【Abstract】 This paper systematically summarizes the development, process style and biology theories involved in the SBRs process. And on that basis, the paper searches automatic control, the change of COD value and the shock resistant capacity of typical SBR process, as well as the influence of the heavy metals chrome ion on SBR and the activated sludge of SBR to the absorption of the chrome ion is also studied. Now the summary of the research result is as follows:(1) The experiment adopts the PLC technique to carry out the SBR process automatization circulation successfully, summarizing its PLC plait distance technique to the movement characteristics of SBR process. In the light of the experiment the thesis puts forward the concept of the cyclic performable occurrences ,and give a plait distance mode of the cyclic performable occurrences.(2) Making use of SBR to treat the organic wastewater can obtain good result .But the ways of treating the high concentration and the low concentration organic sewage are not the same: To the low concentration organic sewage, we must raise the organic loading by high drain rate or shortening the time of the period of reaction; and to the high concentration organic sewage, we must reduce the organic loading by low drain rate or lengthening the time of the period of reaction(3) The SBR process has a very strong ability to bear the impact load .The ability of its bearing the organic impact load, on the one hand, has something to do with the concentration of the activated sludge, on the other hand, has something to do with the time of reaction of SBR process. The influence of the organic impact load to the SBR process is not to destroy the activated sludge system of SBR, but to cause absorption ability of the activated sludge to be exceeded by the organic sewage .While recovering the primary wastewater normally, the system will also recover normally. In order to explain the bearing impact load phenomenon of SBR, this text puts forward a hypothesis," the stockpile - usage (generation)", to explain the ability of the bearing organic impact load of SBR. (4) The chrome load can be divided four scopes according to the toxicity function of the chrome ion to the mixed liquor volatile suspended solid (MLVSS): beating scope (0～～30mg/gmlvss)、collapse scope(30～～65mg/gmlvss)、flocculation scope (70～～100mg/gmlvss)、the scope of breaking cell (＞100mg/gmlvss). The size of SVI has influence to this scope value. When the SVI value is low, the scope value of top and bottom limit will increase; and when the SVI value is high, the scope value of top and bottom limit will decrease.(5) The chrome load and SVI all influence the absorption of the chrome ion by the activated sludge of SBR process. When the chrome load is under 30mg/gmlvss, its influence on the absorption of chrome ion by the activated sludge of SBR system isn’t very much, but will diminish with the aggrandizement of SVI. When the chrome load level is over 30mg/gMLVSS, because of the toxicity function of the chrome ion, the absorption ability to the chrome ion of the activated sludge of SBR process will descend consumedly.(6) The toxicity function of the chrome ion will cause the physical volume of the activated sludge to enlarge, but the flocculation function of the chrome ion will then cause the physical volume of the activated sludge decrease. Their interactions will cause the sediment sludge volume in 30 minutes present a wave type variety with the aggrandizement of the chrome load (namely the aggrandizement of the chrome ion concentration in the aqua). The size of SVI influences the function of the chrome ion to the size of the sediment sludge volume in 30 minutes, and makes the wave type variety characteristic become obvious or not obvious.(7) All the chrome ion toxicity function, the flocculation function and the activated sludge specific gravity gain that the chrome ion result in are the factors that influence the subsidence process of the activated sludge. The SVI value also influences the function of the chrome ion to the subsidence process of the activated sludge obviously in the meantime. The factors of controlling the settling velocity of sludge and controlling the final sediment sludge volume are not same. The settling velocity of the activated sludge will increase with the increment of the chrome ion concentration, and it will increase with the increment of the chrome ion concentration, but the finial volume of the activated sludge is the interactive result of the toxicity function and the flocculation function by the chrome ion.(8) The activated sludge whose SVI is in 120ml/gmlvss or so is more special .The activated sludge at this SVI or so, along with the aggrandizement of the chrome load, will cause negative bulge phenomenon, namely, in the low chrome concentration, the settling velocity of sludge will speed, but in the high chrome load level, the sludge volume becomes bigger than the sludge volume of comparison, and the settling velocity of sludge become slow. Certainly, this is in the scope of the chrome load in the article experiment.更多还原