CAST工艺处理城市污水的强化脱氮研究

介绍了镇江征润州污水处理厂CAST工艺的运行情况，结合该厂实际运行状况开展了强化脱氮效果的生产性试验研究。结果表明，该工艺对COD、SS和TP的去除率均能维持在80％以上，但对氨氮的去除效果较差；在该厂运行模式下，控制进水／曝气前30min的DO〈0．5mg／L、进水／曝气后30min的DO浓度在1．0-3．0mg／L、纯曝气DO浓度在2．0-3．0mg／L，可以实现同步硝化反硝化和硝化／反硝化作用下的共同脱氮，使脱氮效率提高了57％左右；在控制进水／曝气后DO〈0．5mg／L、纯曝气DO浓度在1．0-3．0mg／L的条件下，可以实现同步硝化反硝化作用下的脱氮，但较难实现理想的脱氮效果。

Study on Enhanced Biological Nitrogen Removal from Municipal Wastewater by CAST Process

The Cyclic Activated Sludge Technology(CAST) was applied to treat municipal wastewater from Zhengrunzhou Wastewater Treatment Plant.The full-scale experiment on enhanced nitrogen removal was carried out.Results show that CAST is capable of removing biodegradable COD,SS and TP,and that the average removal rates are up to 80%.However,the effect of nitrogen removal is not as good.SND and SQND can be achieved and nitrogen removal increased by 57% under the conditions: the concentration of dissolved oxygen is controlled below 0.5 mg/L for 30 minutes before inflow/aeration,(2.0)-3.0 mg/L during pure aeration,and 1.0-3.0 mg/L for 30 minutes after inflow/aeration.In addition,SND can be achieved but without higher effect of nitrogen removal when concentration of DO is controlled below 0.5 mg/L after inflow/aeration and 1.0-3.0 mg/L during pure aeration.