Study On The Engineering Design And Operation Control Technology Of Coking Wastewater Treatment

With the overtly rapid expansion of iron industry, coking industry has been improved continuously which, at the same time, leading to the severely environment pollution. Coking wastewater is a kind of typical high concentration of refractory organic industrial wastewater which includes high percentage of COD 、 NH3-N as well as refractory organics. The experiment adopt A2/O2 process to treat the coking wastewater by comparing the A/O、A2/O、A/O2 and A2/O2 processes. the In the coking wastewater treatment process, concentration range of water COD was 2000~2500 mg/L, NH3-N water concentration range was 100 mg/L~150 mg/L, sewage discharge meet the needs of the General Wastewater Discharge Standards Ⅱ(GB8978-1996).The main structure was made according to the determinate process, then construction and acceptance checks were carried out, the system would started if the check was up to standard. In the coking wastewater treatment process,the COD removal efficiency of anaerobic, anoxic, aerobic and contact oxidation reactors were 25.7%、22%、74% and 59.3%, respectively. The relevant average organic loading rate removed were 0.63、0.63、0.65 and 0.233kg/m3/d, respectively. The NH3-N removal efficiency were-26.2%、5.7%、43% and 82.9%, respectively, and the relevant average organic loading rate removed were-0.04kg/m3/d、0.012kg/m3/d、0.05 kg/m3/d and 0.082kg/m3/d, respectively. Among them, the removal rate of COD in the aerobic reactor account for 48% of the total removal rate, the average COD removal load is 0.65 kg/m3 / d, the largest amount of COD removal shows that COD removal is mainly occurred in aerobic reactor. Whereas NH3-N removal mainly occurs in the contact oxidation reactor, accounted for 50% of the total removal rate, average removal load of NH3-N is 0.082 kg/m3 / d.Overall, the actual operation results illustrated that: removal efficiency of COD and NH3-N were above 94% and 87%, respectively, and removal efficiency of Volatile phenols, sulfide, oil and cyanide were all exceed 90%, which met the reuse standard of wastewater. The process had the advantages of simple operation and high treatment efficiency. Therefore, A2/O2 process was feasible both in technology and economy. Therefore, A2/O2 process was feasible both in technology and economy.