悬浮填料氧化沟脱氮除磷的中试研究

STUDY ON NITROGEN AND PHOSPHORUS REMOVAL EFFECT OF A PILOT SCALE SUSPENDED CARRIER OXIDATION DITCH PROCESS

通过正交实验研究了溶解氧（DO）含量、污泥回流比、污泥龄（SRT）对悬浮填料氧化沟系统脱氮除磷效果的影响，并对COD、NH4^＋-N、TN、TP去除率的极差和方差进行了分析。结果表明，DO含量对系统COD、NH4^＋-N、TN、TP的去除均有显著影响，污泥回流比对系统NH2-N、TN、TP的去除有显著影响，SRT仅对TP的去除有显著影响。悬浮填料氧化沟系统脱氮除磷的优化运行工况为氧化沟DO的质量浓度0．8-1．2mgm，污泥回流比75％-100％，SRT为10-15d。在此优化工况下运行，出水COD、NH2-N、TN达到GB18918-2002标准中的一级A标准，TP达到一级B标准。

The effects of dissolved oxygen （DO） content, sludge return ratio （r） and sludge retention time （SRT） on removal of nitrogen and phosphorus in a suspendedcarrieroxidationditchprocesswerestudiedthroughorthogonalexperiment. COD, NHa＋-N, TNandTPremovalefflciencyoftheexperimentwere analyzed based on range analysis and variance analysis. The results showed that DO content had significant influence on decarburization, nitrogen and phosphorus removal; sludge return ratio had significant influence on nitrogen and phosphorus removal; SRT had significant influence on phosphorus removal. The optimal operating conditions of the system was that the mass concentration of DO in the ditch was 0.8- 1.2 mg/L, sludge return ratio was 75%- 100%, and sludge retention time was 10- 15 d. COD, NH4＋oN and TN of the effluent met the first level A criteria in GB 18918 --2002, TP met the first level B criteria.