Study On The Affect Of The Mixed Treatment Of The Dye And Papermaking Wastewater To A/o Process

The dye wastewater from the dye product, which has high chroma, high COD, high salinity, high toxicity and low biodegradability, cannot be biodegraded. To some extent, the pulp and paper wastewater has good biodegradability, which is suitable for biological treatment. So it is valuable to study effect of the dye mixed with papermaking wastewater to the biochemical systems.Microbial breathing curve method was used to test the biodegradability and toxicity of dye wastewater and papermaking wastewater in this work. Furthermore, the biodegradability of the mixed water was studied with different mixed concentration,reaction temperature and reaction time as well as different sludge concentration. Anaerobic pretreatment to dye wastewater or the mixed wastewater was chose to reduce its toxicity and improve its biodegradability,which can be handed by aerobic treatment.The experimental results showed that the dye wastewater mixed with paper- making wastewater has a certain inhibition to microbial respiratory. And the inhibition was more obvious with the higher concentration of the dye wastewater. When the concentration of the dye was less than 0.3 mg/l. The dye has lower toxicity to the microbe. The microbe could restore normal breathing after a period time of adaptation as the concentration of the dye was between 0.3-0.4 mg/l When the concentration of the dye was higher than 0.5mg/l, the microbe respiratory was obviously restrained. Meanwhile, the experimental results showed that the dye wastewater mixed with the paper-making wastewater in a certain concentration range has no influence to the subsequent aerobic treatment. The biodegradability was improved obviously with the conditions of anaerobic pre-processing time,2-3 hours, the reaction temperature,25-30℃, the sludge concentration,4-5g/l.Anaerobic pretreatments to dye wastewater or the mixed wastewater can promote to reduce the processing difficulty and risk, and ensure the stable and efficient operation of activated sludge system, as well as to provide reference for similar treatment of mixed wastewater.