Mathematical model Moving Bed Biofilm Reactor (MBBR) In saline wastewater treatment

Due to its adverse effects on the activity and cellular structure of microorganisms high salt concentration significantly reduce the efficiency of biological treatment processes of saline wastewater. Synthetic wastewater composed of diluted molasses, urea, salts of buffer phosphate and various concentrations of salt (0.7- 2.5% NaCl), was treated in a Moving Bed Biofilm Reactor unit (MBBR). In order to start up, the recycled sludge flow of activated sludge culture obtained from the wastewater treatment plant was added (used as inoculum) to MBBR reactors that 50 % of the reactor’s volume were filled with the carrier elements, shaped like small corrugated cylinders, are made of polyethylene.The effects of important process variables such as COD loading rate (Ls), hydraulic loading rate (Q/A) and salt concentration on the performance of the system were investigated.An empirical mathematical model describes the system’s performance in various salt concentrations and COD loading rates separately. Using the experimental data, the constants of model were determined.The obtained equations can be used in MBBRs systems under similar conditions and with in the ranges tested for the parameters.