Application And Study Of Technical Optimization On Optimizing And Upgrading Taking MBBR For Towns Wastewater Treatment Plant

The eutrophication of water body has been the main water environmental problems.Taking effective measures to control nitrogen and phosphorus is the fundamental way ofsolving the eutrophication of water body. According to the more and stricter dischargestandard of pollutants, most of municipal wastewater treatment plants are confrontedwith the request of upgrading construction. This study regards Licunhe wastewatertreatment plant as the research object. According to the practical situation and thecomparison of WWTP，before and after retrofitting with moving bed biofilm reactor, themain research target is to enhanced in removing nitrogen and phosphorus of secondaryeffluent water. This study mainly include the analysis of TN exceeding standard byproductive experiment. In order to improve the denitrification efficiency, the study takesodium acetate and supernatant of sludge tihckener as external carbon to enhancedenitrification ability. Make sure the optimal dosing quantity of sodium acetate andsupernatant of sludge tihckener through the lab-scale test and prove it throughproductive experiment. Besides, the lab-scale test is used to study the nitrificationability of MBBR.The results show that:1. The study of comparison of efficiency of system before and after retrofitting.（1） In the normal influent quality of normal temperrature and low temperratureconditions,the NH3-N and TP removal efficiency after retrofitting is better than beforethrough the comparison.COD and NH3-N of effluent meet the first level A of "DischargeStandard of Pollutants for Municipal Wastewater Treatment Plant".SometimeTP exceedstandard and need tertiary treatment.Most of time TN exceed standard.（2） Compared to the efficiency of two biological treatment systems of first-phaseproject, NH3-N and PO43--P removal efficiency improved after retrofitting with MBBRand volatility of the effluent quality is very small.（3） MBBR is used to improve the abilities of resisting impact and low temperratureand enhance the nitration function through the lab-scale test under the conditions of lowand normal temperrature.2. The study of technical optimization of improving treatment capacity after retrofitting（1） Under the conditions of low carbon source, low reflux ratio and lowtemperrature, most of time COD and NH3-N of effluent can meet the first level A of "Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant", but TNcan not meet the first level A standard.（2） Under the conditions of adding carbon source, reasonable reflux ratio andnormal temperrature COD and NH3-N of effluent can meet the first level A of"Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant", and TNcan meet the first level A standard in most time.（3） Make sure the optimal dosing quantity of sodium acetate and supernatant ofsludge tihckener respectively through the lab-scale test.The result show that the optimaldosing quantity of sodium acetate is40-60mg/L (denoted by COD_Cr) and influent mixwith supernatant of sludge tihckener with30:1.The denitrification of system is the best.