Study On The Establishment Of Immobilization System And The Performance Of MSG Wastewater Treatment

Microbiological technology was used to treat Monosodium glutamate（MSG）wastewater both to clean water and avoid secondary pollution.Dominant bacteria were extracted from MSG wastewater and mycelial pellets were immobilized to form combined mycelial pellets.The effect of different preparation conditions and treatment conditions on the performance of treating MSG wastewater was investigated.Microphotography,SEM,BET,FTIR,Zeta potential variation,p H variation,extracellular polymer EPS content,3D fluorescence spectroscopy,EDS-mapping techniques were used to investigate the mechanism of treatment of MSG wastewater.The main findings show that:（1）The addition of 0.6 g beef paste,2 g peptone and 2 g Na Cl in 200 m L liquid medium and p H=7 were the best preparation conditions for the dominant bacteria medium.The maximum removal rate of COD and NH₃-N was 40.44%and 30.16%respectively when dominant bacteria were 0.5%,the reaction temperature was 35℃,the reaction time was 6h and the shear force was 120 rpm·min^-1.Infrared spectral and strain identification showed that the alcohol-phenol conjugates,carboxylic acid monomer substances or amide substances on the surface of the dominant bacteria were involved in the reaction during the treatment of MSG wastewater.The results of strain identification indicated that the dominant bacteria were Bacillus sp.（2）1 m L of spore suspension per 150 m L of a liquid medium with initial p H=6,incubated at 160 rpm·min^-1 and 30℃for 72 h was the best condition for mycelial pellets.The optimum preparation conditions for combined mycelial pellets were 3-4 mm mycelial pellets yields,incubated time was 8 h,initial p H=6 of the suspension,incubated temperature was 30℃and 160 rpm·min^-1 shear force.The characterization results showed that the formation of combined mycelial pellets was the result of functional group interaction,electrostatic attraction and microbial mutual stimulation.（3）The maximum removal rate of COD was 36%and NH₃-N was 17%for 10 g fresh mycelium pellets and combined mycelial pellets at 35℃,120 rpm·min^-1 and 12 h.The maximum removal rate of COD was 47%and NH₃-N was 33%for 10 g combined mycelial pellets at 35℃,120 rpm·min^-1 and 12 h.The physical adsorption of COD and NH₃-N by combined mycelial pellets was not the main treatment method and the biological metabolism was the main treatment method.