Research And Practice Of Pulping And Papermaking Wastewater Treatment Process

The large amount of waste water produced in the paper industry has been listed as a key source of water pollution in my country,and it is also a key target of environmental supervision.With the continuous improvement of national wastewater discharge standards,companies need to continuously improve their own wastewater treatment capacity to ensure that the quality of production wastewater is stable and meets the discharge standards.This subject is based on the upgrading and technical improvement of the biochemical wastewater treatment system in the supporting wastewater treatment plant of a pulp and paper company in Yangzhou.Through understanding the source of pulp and paper wastewater,research on pulp wastewater treatment methods,and analysis of wastewater from a pulp and paper company in Yangzhou Deal with the problems in the process and propose a process modification plan.Anaerobic+A/O+Fenton oxidation+coagulation sedimentation combined process is used to treat waste water produced in the pulping and paper production process of waste paper.Among them,IC anaerobic reactor+A/O is used to treat general organic matter,and Fenton oxidation is used to treat difficult The degraded organic matter is finally combined with coagulation and sedimentation to remove the remaining organic matter to ensure that the wastewater is discharged up to the standard.The main research results obtained in the thesis are as follows:(1)The combined process of IC anaerobic+A/O+Fenton oxidation+coagulation sedimentation to treat pulp and paper wastewater is stable,and the effluent reaches the "Water Pollutant Discharge Standard for Pulp and Paper Industry"(GB3544-2008).(2)The effect of Fenton oxidation reaction time,temperature,pH value,FeSO4·7H2O and hydrogen peroxide dosage on the treatment efficiency was discussed.The primary and secondary relationship between the affected factors is:H2O2 dosage>FeSO4·7H2O dosage>pH value>reaction time.(3)Fenton oxidation system has the best removal efficiency when the pH value is 4,the dosage of H2O2 with a concentration of 27.5%is 500mg/L,and the dosage of FeSO4·7H2O is 800mg/L.The best reactivity and environmental treatment conditions for the subsequent coagulation sedimentation were:water temperature 30 degrees Celsius,pH value 8,and PAM dosage 4 mg/L.The COD removal rate of the combined process under this condition is 66.99%.The operating cost is about 3.16 yuan/ton.(4)The actual operation effect of the process proves that the process combination of anaerobic+A/O+Fenton oxidation+coagulation sedimentation has a stable effect.The anaerobic system removal rate is stable above 80%,and the A/O removal rate is stable at 60%Above,the influent COD and the effluent COD are less than 65mg/L,and the total removal efficiency can reach more than 98%,which can stably meet the pulp and paper wastewater discharge standard.