反硝化颗粒污泥系统和反硝化生物膜系统深度脱氮对比研究

Comparative Study on Advanced Nitrogen Removal of Denitrifying Granular Sludge System and Denitrifying Biofilm System

对比分析了反硝化颗粒污泥系统和反硝化生物膜系统在不同进水条件和不同水力停留时间(HRT)下的脱氮效果。结果表明,当进水COD较高即外部碳源较为充足时,反硝化颗粒污泥系统和反硝化生物膜系统脱氮效果接近;而当进水总氮浓度较高即外部碳源受限时,生物膜系统的脱氮效果优于颗粒污泥系统。在不同的HRT条件下(3~6 h),反硝化生物膜系统的深度脱氮效果均优于反硝化颗粒污泥系统,且当HRT=5 h时,两系统的脱氮性能均达到最高。实验结果表明反硝化生物膜系统在脱氮性能方面略胜一筹。但是,结合经济性和去除性能进一步分析可知,与生物膜系统相比,颗粒污泥系统具有占地面积小、无载体成本等低成本的显著优势,在既有工艺出水深度脱氮的工程实践中,可优先选择反硝化颗粒污泥工艺,并可通过控制颗粒粒径和系统运行参数等措施强化脱氮性能。

In this study,the effects of denitrification granular sludge system and denitrification biofilm system under different influent conditions and different hydraulic retention time(HRT)were compared and analyzed.The results showed that when the influent COD is high(the external carbon source is sufficient),the denitrification effects of denitrifying granular sludge system and denitrifying biofilm system are similar.However,when the total nitrogen concentration of the influent was high(the external carbon source of denitrification was limited),the nitrogen removal effect of the biofilm system was better than that of the granular sludge system.Under different HRT conditions(3~6 h),the advanced denitrification effect of the denitrifying biofilm system is better than that of the denitrifying granular sludge system,and when HRT=5 h,the denitrification performance of both systems reaches the highest.The experimental results showed that the denitrifying biofilm system is superior in nitrogen removal performance.However,combined with further analysis of economy and removal performance,compared with the biofilm system,the granular sludge system has the significant advantages of a small footprint,no carrier cost and other low costs.In the engineering practice of advanced denitrification of effluent from the existing process,the denitrification granular sludge process can be preferred,and the denitrification performance can be enhanced by controlling the particle size and system operating parameters.