纤维素对污水生物处理系统性能的影响及机理分析  

Impact and Mechanism of Celluloses on the Performance of Biological Wastewater Treatment

作　　者：郝晓地[1,2] 饶志峰 刘然彬 刘杰 HAO Xiao-di;RAO Zhi-feng;LIU Ran-bin;LIU Jie(Key Laboratory of Urban Stormwater System and Water Environment,Beijing University of Civil Engineering and Architecture,Beijing 100044,China;SinoDutch R&D Centre for Future Wastewater Treatment Technologies,Beijing 100044,China;Capital EcoPro Group,Beijing 100044,China)

机构地区：[1]北京建筑大学城市雨水系统与水环境教育部重点实验室,北京100044 [2]中-荷未来污水处理技术研发中心,北京100044 [3]首创生态环保集团,北京100044

出　　处：《中国给水排水》2021年第21期1-6,共6页China Water & Wastewater

基　　金：国家自然科学基金资助项目(51878022);北京“未来城市设计高精尖中心”项目(2021)。

摘　　要：厕纸等纤维素成分在污水中含量不菲,它们在生物处理过程中非但很难降解,反而会增加系统的运行负担。因此,国际上已开始从污水中分离纤维素的研究与实践。为探讨纤维素对污水生物处理系统性能与运行的影响,采用小试变形UCT工艺考察了它们的影响程度并揭示出影响机理。结果显示,纤维素存在只会在短期内影响COD、N、P去除,表现为曝气量不足。只要提高2~3倍曝气量便可恢复出水水质。微观研究揭示,纤维素线性形态和含有大量官能团特点能够明显提高污泥絮体密实度,从而导致絮体内氧传质效率下降,这也是纤维素存在时需要加大曝气量的根本原因。纤维素对絮体的网捕卷扫作用使絮体致密的好处是可强化同步硝化反硝化(SND)作用,亦可减少出水SS含量。综合衡量,预处理分离纤维素有利于节能降耗,况且,纤维素大部分成分在曝气过程是难以降解的,最终会进入剩余污泥之中,增加污泥量。可见,从污水中回收纤维素不仅可实现废物资源再利用,亦有助于节能降耗,同时为升级污水处理增加处理空间。Wastewater contains a certain amount of celluloses which is not only difficult to be degraded in the biological treatment process,but also increases the burden of the system.As a result,the separation of celluloses from wastewater has been studied and practiced.To further clarify the influence of celluloses on the performance of biological wastewater treatment,a lab-scale modified UCT reactor was constructed to study its impact on pollutants removal and the associated mechanisms.The results indicated that the presence of celluloses in the influent resulted in the deterioration of removing COD,nitrogen,and phosphorus in a short term due to the deficiency of dissolved oxygen(DO).The effluent quality was restored after doubling or tripling the aeration rate.In addition,the microscopic examination showed that the linear morphology and vast amounts of functional groups of celluloses could significantly increase the density of sludge flocs.Consequently,the mass transfer of DO in the flocs was undermined.This was also the reason why there was a need to increase the aeration rate to obtain a favorable performance when celluloses were present.However,this consolidation of sludge and the net trapping and sweeping effect had a positive effect on the simultaneous nitrification and denitrification(SND)capacity and the SS retainment.Overall,recovery of celluloses before the biological unit can reduce the energy input and costs,otherwise,they will contribute to the excess sludge production.In other words,the recovery of celluloses from wastewater can be valorized and leveraged to save energy and costs as well as to increase the capacity of wastewater treatment.

关 键 词：纤维素 脱氮除磷 絮体 氧传质速率 同步硝化反硝化 节能降耗 

分 类 号：TU992[建筑科学—市政工程]