Industrial hypersaline wastewater biochemical treatment of salt-tolerant sludge acclimation and its mechanisms

The feasibility, character and biological process of industrial hypersaline wastewater biochemical treatment of salt-tolerant sludge acclimation were studied through comparing the activated sludge acclimation under high and low saline conditions. The result showed that taking salt as the selective pressure, salt-tolerant sludge with high degradation activity could be acclimated. When the NaCl concentration is 45 000mg/L and the volumetric loading is 1.6kgCODCr/(m3d), the CODCr removal rate could reach to 96.6%. Analysis of microbial communities in the acclimation of salt-tolerant sludge shows that the amount of salt-tolerant phenyl acetic acid-degrading bacteria increased from 109cfu/(gVSS) to 1011cfu/(gVSS) in 15 days, with increase of influent salt concentration thus becoming the dominant physiological community in the sludge.