【作者】 赵娜；

【导师】 王涛；

【作者基本信息】 重庆大学 ， 环境工程， 2005， 硕士

【摘要】 目前,我国城市污水氮磷污染严重,而许多城市污水厂采用的工艺流程复杂、构筑物多、回流系统多、运行条件要求高,导致污水处理设施存在建设投资和运行成本高、运行管理繁琐、管理技术水平要求高等一系列问题,这些问题无疑会制约我国污水处理事业的发展。据此,本试验研究课题组在前期研究中提出了具有高效、节能、管理方便等优势的合建式三环工艺,但该工艺在处理低碳源城市污水时,存在除磷脱氮效果不够理想的问题。本试验研究就是针对目前普遍存在的城市污水水质浓度偏低的问题,在分析综合多种连续流除磷脱氮工艺特征的基础上,综合倒置A2/O 工艺、分段进水除磷脱氮工艺、OCO 工艺、Orbal 氧化沟工艺和一体化氧化沟工艺等多种工艺运行方式的优势,对前期课题组提出的合建式三环模型进行改进,集成新的多环处理系统来强化低碳源条件下系统脱氮除磷的能力。本试验以污泥龄、好氧区水力停留时间、回流比以及溶解氧浓度为控制因素,各因素取三水平,用正交表来安排试验。试验结果表明,污泥龄(SRT)对系统脱氮除磷效果影响最为关键,接下来是水力停留时间(HRT)、回流比、溶解氧浓度(DO)。其中,较长的污泥龄、水力停留时间、较高的回流比以及较低的溶解氧浓度都有利于提高系统在低碳源条件下的脱氮除磷效果。在此基础上,进行了延长污泥龄为30d、好氧区水力停留时间为16hr 的补充试验,结果表明,较长污泥龄和水力停留时间确实有利于低碳源污水氮磷的去除,出水COD、氮、磷满足排放标准,其中TN 去除率为81.24%,TP 去除率71.09%。本试验研究还对外沟好氧区的同时硝化反硝化进行了试验证实,结果表明,外沟在SRT=20~25d,HRT=12hr,回流比=400%,DO=0.5～1mg/L 的条件下,同时硝化反硝化脱氮率可达34%左右。此外,本研究通过试验证实本系统在低碳源条件下得出的优化控制条件不仅适用于水质偏低的城市污水,对一般水质的污水有更好的去除效果。本试验研究提出的低碳源城市污水脱氮除磷的运行方式和控制参数可以为目前我国城市污水处理厂进水水质偏低、氮磷去除效果不佳的现实情况提出一套行之有效的解决方法,试验结果对污水处理厂的运行和设计具有一定的指导意义。更多还原

【Abstract】 At present, the contamination of nitrogen and phosphorus is serious in our country, and many WWTPs use complex processes which have too many structures, complex feedback system and need strict working condition, all of those result in the sewage treatment establishments have high costs of construction and operation, fussy condition and high technique need for keepers and so on. Those problems will inevitably influence the development of environment protect project in our country. So highly efficient, energy-saving and simply running Combined Triple Circle Technology is invented in prophase study, but this process dosen’t have good nitrogen and phosphorus removal effect for insufficient carbon source sewage. Based on analysis of spacial relationship of several continuous removal phosphorus and denitrification process, integration of the advantage of many continuous flow nitrogen and phosphorus removal process, such as the inverse A2/O, subsection influent removal phosphorus and denitrification process, OCO process, Orbal oxidation ditch, and integrated oxidation process and so on, combination with new theory on removal phosphorus and denitrification, adoption of basic form of Combined Triple Circle process model, a kind of new simple wastewater treatment technique called multi-loop reactor to improve the treatment effect of actual low-concentration influent is brought forward in paper. Four parameters were selected in multi-loop reactor:SRT、HRT、feedback ratio and DO in aerobic zone, and each parameter has three levels. The results show that: SRT is the first important parameter, successively is HRT、feedback ratio and DO in aerobic zone, and long SRT、HRT, big feedback ratio and low DO in aerobic zone is advantaged for nitrogen and phosphorus removal under low-concentration influent. Based on this result, the complemental test of SRT=30d、HRT=16hr is carried through and confirm that long SRT、HRT are really advantaged for nitrogen and phosphorus removal, COD、TN、TP of effluent is up to waste discharge standard, and the removal ratios of TN and TP is 81.24%and 71.09%. The result of simultaneous nitrification and denitrification (SND) in outer loop shows that: the nitrogen removal rate of SND is about 34% at the condition of SRT=20~25d、HRT=12hr、feedback ratio=400% and DO=0.5~1mg/L. Besides, the result show that: those parameter levels are not only advantaged for low-concentration influent, but for common-concentration sewage. The running mode and parameter levels for nitrogen and phosphorus removal could effectively resolve problem of low removal effect under low-concentration influent, have practical meaning.更多还原