Research Of Activated Sludge And Biofilm A/O Process On The Treatment Of Turpentine Processing Wastewater

The main production of turpentine processing are pine oil,terpineol, α-pinene, β-pinene and other terpenes fragrance,it produce a large number of acid wastewater of highconcentration, which includes many organic pollutants such as phenolics, tannic acid, resinacid, surfactants, oxalic acid and oxalate, organic colours and emulsified oleoresin andturpentine. Such wastewater with many suspended solids and high toxicity is difficult to bebiochemical degraded and will have a bad effect on environment. This paper briefly studythe wastewater from a turpentine processing company by activated sludge and biofilm A/Oprocess, the process of flocculation sedimentation and adsorption combined The Fe/Cmicro-electrolysis and Fenton oxidation process are to reduce COD and improve B/C. Themain contents and results of the experiment are as follows:The research on the treatment of turpentine processing wastewater was performed bythe process of flocculation sedimentation and adsorption. The research mainly focused onthe screening of flocculant and resin, the effect of temperature, reaction time andadsorption flow rate on the absorption, the effects of desorbent on desorption. The resultsshowed that PAM was the best flocculant; Polyurethane was the best absorption materialwhen pH value was7and the absorption flow rate was1BV/h;3BV Sulfuric acid and2BV water showed a good performance on desorption at room temperature when desorptionflow rate was1BV/h, the desorption rate can be92.3%. Polyurethane still kept highabsorptive capabilities after five times of absorption-desorption cycles; The initialwasterwater whose COD was40000～60000mg/L can be reduced to16000～24000mg/Lby the treatment of the process of flocculation sedimentation and adsorption, the totalremoval of COD can be up60percentage.The Fe/C micro-electrolysis and Fenton oxidation combined process was used to treatthe turpentine processing wastewater after the process of flocculation sedimentation andadsorption. The effect of amounts of iron, m(Fe):m(C) and pH on the treatment efficiencyof wastewater was discussed in the Fe/C unit; The effect of dosing quantity of H2O2,reaction time, UV and ultrasonic wave on the treatment efficiency of wastewater wasdiscussed in the Fenton unit. The results showed that the COD and chroma removalefficiency was84.2%and96%, BOD5/COD was improves from0.12to0.41, when irondosing was100g/L, m(Fe):m(C)was1and pH was3; The COD removal was98.5%,BOD5/COD was improves from0.41to0.65, when the dosing of H2O2was8mL,pH was3and ultrasonic power was100W. The COD of the wastewater treated by Fe/C micro-electrolysis and Fenton oxidation combined process was600～1000mg/L, wheniron dosing was100g/L, m(Fe):m(C)was1and pH was3, the dosing of H2O2was10ml/L.The activated sludge and bio-film A/O process was used to treat turpentine processingwastewater after the Fe/C micro-electrolysis and Fenton oxidation. The effects of Nitrogen,gas-water ratio and HRT are mainly studied in this treatment unit. The results showed that ithad the best treatment when the dosing of nitrogen was25mg/L, gas-water ratio was20:1and HRT was10hours. The final COD removal and TN removal can be over94%and75%,the final COD and TN was less than35mg/L and7mg/L, which reached industrialwastewater emission standards.Aerobic denitrification strain T1with a high denitrification performance was screenedin this study, physiological and biochemical tests and16S rDNA test showed it had the thehighest similarity with the strain Rhizobium pusense, which can be99.63%.Denitrificationperformance study results showed that denitrification rate of T1can be over85.3%, whencarbon source was sodium citrate, C/N was10, the rotation speed was150r/min and thetemperature was30℃.