大型地下式污水处理厂中臭氧处理工艺的设计

Design of Ozonation Process in Large Underground Sewage Treatment Plant

天津市某大型地下式污水处理厂采用臭氧工艺作为深度处理工艺,用于去除污水中的难降解COD。该工程设计规模为60×10^(4)m^(3)/d,出水水质达到天津地标A标准的要求。臭氧工艺系统主要包括液氧站、臭氧制备间、臭氧接触池、尾气破坏器间等。详细介绍了臭氧系统各处理单元的设计细节、设备排布以及管道路由等。设计要点包括:制备间靠近箱体外边缘布置;发生器室设计三面防爆墙,一面泄压墙;外循环冷却水回水至超滤出水渠道,可节省冷却水的用量;每组臭氧接触池分两个点投加臭氧,投加比例为1∶1。设计重点考虑了臭氧系统各建(构)筑物之间的整体关联性,以保证臭氧系统的出水水质。

A large underground sewage treatment plant in Tianjin adopted ozonation technology as an advanced treatment process to remove refractory COD in sewage. The design treatment capacity of the project was 60×10^(4)m^(3)/d, and the effluent water quality was required to meet the limitations of Tianjin local A discharge standard. Ozonation process system mainly consisted of liquid oxygen station, ozone preparation room, ozone contact tank, exhaust destruction room, etc. The present work mainly discussed the overall process design of the ozone system, and introduced the design details of each treatment unit, equipment arrangement and pipeline routing. The key points were as follows: the preparation room was arranged near the outer edge of the box;the generator room was designed with three explosion-proof walls and one pressure-relief wall;external circulation of cooling water flowed back to ultrafiltration outlet channel to save the consumption of cooling water;each group of ozone contact tank had two feeding points with dosage ratio of 1 ∶1, etc. The design focused on the overall relationship among various structures of the ozone system to ensure the effluent water quality of the ozone system.