Experimental Study Of Bathing Wastewater Treatment Based On Immobilized Biofilm

Bathing wastewater has large volume, light pollution characteristics, as a kind ofquality-recycled water source in the reclaimed water reuse was received much concerned. Withthe idea of desperation treatment and in-sit reuse proposed, the bathing wastewater will be thefirst choice of reclaimed water reuse.In view of LAS in the bathing wastewater has poisoning effect on microbial physiologicalactivity and more difficulty to be removed relatively, the paper take the method of subculturingpassage for activated sludge many time to get bacterial suspension which LAS degradingbacteria predominant. After purification and separation, the LAS degrading bacteria be got, bythe characteristics of morphological and physiological observed, the LAS degrading bacteria hasseveral characteristics: small colony which surface moisture and smooth, have processes,milkiness or yellow, gram stain test negative, methyl red test negative, nitrate reduction testpositive, hydrogen peroxide test positive; the optimum pH is7, the optimum growth temperatureis30℃.Applying bacterial suspension to single factor test which about shaking-flask test. Theinfluence of inoculation amount, broth content, shock frequency and pH were investigated. Theresults showed that when inoculating bacterial suspension (OD=0.4) amount at the percentage of4, broth content is100mL, shock frequency is150r/min and pH=7, the treatment effect is better.The removal rate of LAS, COD and NH3-N respectively is77.19%,86.33%and62.60%.Applying ACF high adsorption properties to treatment bathing wastewater, the influence ofdosage of ACF, adsorption time and the change of pH in water were investigated in single factortest.The results demonstrate: ACF has good adsorption effect on LAS relatively, when thedosage of ACF is10g/L, adsorption time is60min, pH=6, the removal rate of LAS, COD andNH3-N respectively is50.89%,41.75%and24.88%. Adding ACF with different dosage to watersample that concentration of LAS is same, ACF adsorption LAS is more in line with theFreundlich adsorption isotherm.Take ACF as microbial immobilization carrier material, bacterial suspension and activatedsludge were used to fixing film. After six days steady-state, pass the bathing wastewater into thetank, starting the ACF adsorption device at the same time. Compare treatment bathing wastwatereffect, the result demonstrate: when using ACF adsorption lonely run18days to treat bathing wastewater, alarge amount of black powdery substance flowing out from the tank. but, the ACFfixed biofilm reactor effluent still clarified. It is prove that immobilized biofilm can extend theACF life cycle. The time of using bacterial suspension fixed film is shorter than activated sludgefixed film when the film complete start-up and has better treatment effect on bathing wastewater.When the bathing wastewater rate of flow at inlet is1.5L/h, aeration rate is1.5g/L, under stableoperation condition, the removal rate of LAS, COD and NH3-N respectively is87.14%,85.87%and74.89%. Changed bacterial suspension fixed film reactor hydraulic retention time, analysisthe treatment effect combined with economic considerations, HRT=4is better.