【作者】 冷寒；

【导师】 杨幸；

【作者基本信息】 重庆大学 ， 环境工程， 2007， 硕士

【摘要】 现在城市污水处理厂对氨氮的去除一般都能达标,而对磷的去除难以达到新的国家排放标准,研究污水处理工艺的除磷机理具有重要的实际意义。MSBR(Modified Sequencing Batch Reactor)工艺具有一定的脱氮除磷功能,但是作为一个刚刚开发出不久的污水生物处理工艺,MSBR尚未得到深入、广泛的研究;现有的对MSBR生物除磷机理的研究和探讨还不能满足MSBR工艺发展的需要。在MSBR工艺中对除磷有影响的因素众多,研究各影响因素对MSBR系统除磷的作用对完善MSBR工艺的除磷功能和工艺的设计和运行具有重要的指导意义。本文在前人试验的基础上,在出水氨氮达标的情况下,通过对6池MSBR与7池MSBR工艺除磷影响因素的分析,研究6池MSBR和7池MSBR除磷的机理,找出影响MSBR除磷效果的关键因素,确定各影响因素相对最佳值;对比分析各影响因素对6池与7池工艺除磷的影响,研究各系统的优缺点,试验结果表明:(1)进水COD/P为选定的试验因子中对除磷的影响程度最大的,在6池工艺中,所选因子对除磷影响程度的由大到小的关系为:COD/P>MLSS>R>COD/N;在7池工艺中,所选因子对除磷影响程度的由大到小的关系为:COD/P> R > MLSS >COD/N。(2) 7池工艺为生物除磷创造了更好的条件。7池增加了一个缺氧/厌氧池,消除了进水中的DO和污泥回流带来的NO3-,保证了聚磷菌的厌氧条件下充分释磷;7池工艺中缺氧池位于污泥浓缩池之后,这种流程安排使得7池可以处理比6池进水NH4含量较高的废水,对高浓度NH4有较好的耐受性。(3)两工艺中TP去除率随进水COD/P变化的趋势相同,都为先增大后趋于稳定。6池的转折点出现在COD/P为100时,7池的转折点出现在COD/P为60时。与6池工艺相比,7池能处理磷负荷更高的进水,(4)在6池和7池工艺中,TP去除率随R的增大出现先升后降的趋势。6池工艺的去除率最大值出现在R为0.5时,7池工艺去除率最大值出现在R为0.6时。(5)较理想的污泥回流是在最小的混合液回流量下回流最大量的活性污泥。仅仅用污泥回流比R来衡量回流污泥量是不够的,浓缩池中污泥的沉降性能也是一个重要的参数,对污泥回流量有较大的影响。(6)进水COD/N对MSBR6池工艺和7池工艺除磷的影响上有一定的一致性。6池与7池工艺的SBR缺氧段都发现了反硝化吸磷的现象。(7)厌氧池释磷量也随着进水COD浓度的增加而增加。6池工艺TP去除率随着进水中COD浓度的增加也有所增加,7池工艺TP去除率随着进水中COD浓度的增加表现为先增大后减小的趋势。7池对进水COD浓度的变化比6池敏感,6池工艺比7池工艺耐受的COD进水浓度高,在实际工程应用中,7池工艺的进水COD要尽量保持在一个合适的范围内,以免系统对磷的去除效果出现大的波动。更多还原

【Abstract】 Now, the removal of ammonia nitrogen is successful in most of the wastewater treatment plants (WWTP), and the discharge of ammonia nitrogen could accord with the Integrated Wastewater Discharge Standard. But the emission of phosphorus is always higher than the discharge standard. So, there is greatly practical significance to study the theoretic of phosphorous removal in the WWTP. The Modified Sequencing Batch Reactor (MSBR) could removal nitrogen and phosphorus in wastewater, but the theories have not been studied deeply and widely. Currently, researching about the MSBR is not enough for its development. The parameters that affect biological phosphate removal in MSBR are quite a lot, and for the technology’s design and operation and improving phosphorus removal function, there is guiding significance to research the parameters.This paper based on the forerunner, and on the premise of that the ammonia nitrogen of outlet is controlled within the standard, study the principle of phosphorus removal in 6-tank process and 7-tank process MSBR by analyze the parameters that affect biological phosphate removal in 6-tank process and 7-tank process MSBR. The purpose is to find out the primary factors which affect the phosphorus removal in MSBR, and then comparatively analysis the affection of the parameters to phosphorus removal in 6-tank process and 7-tank process MSBR, to find out the merits and faults of the two processes. The results of the experimentation indicated that:(1) In the selected factors, the most important parameters are influent COD/P ratios. In 6-tank process, the sequence of the factors by degrees which affect the phosphorus removal is: COD/P>MLSS>R>COD/N; in 7-tank process, the sequence is: COD/P>R>MLSS>COD/N.(2) 7-tank process has created much better condition for the biological phosphate removal the 6-tank processs. A anoxia/anaerobic pool is added into the 7-tank process MSBR, and so, the 7-tank process could eliminate DO in influent wastewater and NO3- that mixed in reflux activated sludge, and ensure the sufficiently phosphate release of phosphate accumulating organisms(PAOs) under anaerobic condition. 7-tank process MSBR could be able to treatment higher NH4 concentration in influent wastewater than 6 -tank process MSBR, and could bare high concentration NH4 at the scene that anoxia pool is located behind sludge concentrating pool. (3) Among two techniques, the trend of P-removal ratio is same with influent COD/P ratio, which is stabile after raise first. The turning point of 6-tank process appears at 100 and 7-tank process at 60. Comparing with 6-tank process, 7-tank process can treat higher phosphorus concentrateion in influent wastewater.(4) The P-removal ratio has the trends that ascend first and descend late in both 6-tank process and 7-tank process. The maximum value of P-removal ratio in 6-tank process appease when the R is 0.5, and 7-tank process is 0.6.(5) The better sludge reflux ratio is the ratio that could obtain more quantity of refluxed sludge at less reflux ratio. It is not enough to evaluate the reflux sludge ratio just by sludge reflux. Sludge settlement in thickening tank is also important to the quantity of reflux sludge, and it is an important parameter.(6) There is a certain extent identical that the changing of influent COD/N ratio affects biological phosphate removal from wastewaters. Denitrifying P removal at anoxic phase of SBR appease in both 6 and 7-tank process.(7) The P-release in anaerobic pool increase subsequently when influent COD concentration increases. The P-removal ratio ascend when influent COD concentration increases in 6-tank process, but increase first and decrease late in 7-tank process. The 7-tank process is more sensitively than 6-tank process to influent COD concentration, and 6-tank process could endure higher influent COD concentration than 7-tank process. The influent COD concentration in 7-tank process should furthest be kept in a fit rang.更多还原