Comparison of moving bed biofilm and sequencing batch reactors in salty wastewater treatment of food industries

High concentrations of salt in beach water and some industrial wastewaters resulted in an increase in water salinity، which causes difficulties in wastewater treatment. In this research، the effect of salt concentration (up to 30000 mg/L) on the treatment efficiency rates of saline wastewater in lab- scale batch conditions of Sequencing Batch Reactors (SBR) and Moving Bed Biofilm Reactor (MBBR) were investigated. The results indicated that at low concentration of salinity (0. 5%) the removal rate of 94% in both MBBR and SBR has been achieved but in high concentration (3%) the efficiency of SBR (90%) was more than MBBR (83%). On the other hand attached growth in SBR has more potential to remove salinity. The rate of COD removal was 78 and 85 percent in MBBR and SBR، respectively. In the investigation of shock effect in salinity concentration of 50000 mg/L، the salinity removal efficiencies in MBBR and SBR has decreased to 56 and 68 percent respectively that has been reached to the previous level after 28 days.