AB法工艺脱氮除磷提标改造工程实例

An engineering case:upgrading of nitrogen and phosphorus removal by AB process

山东某城镇污水处理厂对原AB法进行倒置AAO工艺提标改造。将A段曝气池、中间沉淀池改造为缺氧区,原A段污泥回流系统改造为污泥外回流系统,将二沉池污泥回流至A段首端,对原B段内回流系统进行改造,将硝化液回流至A段首端,新建厌氧区串联于原A段、B段之间。工程提标改造充分利用了原有构筑物及设备设施,减少工程投资、节省土地、缩短建设周期。改造后实际运行数据表明,该厂处理出水水质各项指标均优于《城镇污水处理厂污染物排放标准》(GB 18918—2002)的一级A标准。反硝化脱氮碳源投加量降低70%,生化系统剩余污泥产生量减少20%,达到提标节能降耗的目标。

The transformation of AB process into inverted AAO process was applied to upgrading reconstruction of an urban sewage treatment plant in Shandong province.Aeration tank of section A and intermediate sedimentation tank was transformed into anoxic zone.The original sludge reflux system of section A was transformed into sludge external reflux system.The secondary settling tank sludge was returned to the head of section A.The reflux system in original section B was transformed into the system,in which nitrifying liquid was refluxed to the head of section A.New anaerobic zone was connected in series between the original section A and section B.The upgrading reconstruction made full use of the original construction and equipment,reducing engineering investment,saving land and shortening the construction period.The actual operation data after the transformation showed that the effluent quality of the plant was better than the first level A standard of Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant(GB 18918—2002).The carbon source dosage of denitrification was reduced by 70%,and the excess sludge production of biochemical system was reduced by 20%,which achieved the goal of energy saving and consumption reduction.