In view of the problem of exhaust emissions from atmospheric pressure absorption tower can't meet the discharging standard in SINOPEC Yangzi Petrochemical Limited Company,by the implementation of atmospheric pressure absorption tower environmental protection renova-tion project and the addition of low pressure catalytic combustion system(LPCCU)for the ex-haust gas treatment unit,environmental protection treatment level of PTA three units reanches to a new level,and meets the requirements of the new environmental emission standards.