Acclimated Salt-tolerant Activated Sludge for Treatment of High-salinity Industrial Wastewater

Using excess sludge from pure-oxygen aeration tank of a petrochemical wastewater treatment plant as inoculation sludge,the salt-tolerant acclimation of the activated sludge was carried out by progressively increasing salinity loading.The results show that after extended period of acclimation,activated sludge microorganisms are able to survive,grow and reproduce in the high-salinity environment.The acclimated sludge can also endure the impact of high-salinity loadings.When the influent TDS is between 18 g/L and 35 g/L,the average COD removal rate of acclimated sludge in the pure-oxygen aeration tank reaches 85.7%,10% higher than that of the conventional activated sludge.This method is capable of acclimating activated sludge with high salt-tolerance and degradation rate of COD.