Study On The Application Of Ultrasonic Technique In The Disposal Of Wastewater From Polyacrylonitrile Fiber Plant

Wastewater from the polyacrylonitrile fiber production with dry spinning process is highly toxic and biorefractory. In this research, ultrasonic process, Fenton reagent and the combined ultrasonic- Fenton reagent process, followed by a biological treatment process respectively, were used to treat the wastewater from polyacrylonitrile fiber plant with dry spinning process. By comparing the above processes with the other existing ones, a treatment process was put forward to treatment the above wastewater, the effluent of which could meet the national standards. Effects of ultrasonic frequency, PH of the wastewater, the electric sound power and time on the COD and BOD5 removal rate were tested for ultrasonic process, while the effects of C (H2O2), C (Fe2+), pH value and time were tested for Fenton process.After testing the factors of Fenton process and ultrasonic process separately, factors influencing the combined ultrasonic- Fenton reagent process were also studied. During the test of each factor, a comparison was made between the combined process and each single process to verify the effect of combination.Biodegradability of each effluent was tested by the model test method. The untreated effluent, the effluent after flocculation treatment, and the effluent after flocculation- ultrasonic- Fenton treatment were tested separately.The combined flocculation- ultrasonic- Fenton and SBR process, with the COD degradation rate of up to 88.7%, was finally chosen to treat the wastewater, the effluent of which could meet the second national discharge standard.