The Upgrading Experimental Study On Nitrogen And Phosphorus Removal Of SBR Process

Serious contamination of water resources in China resulte in eutrophication problems more and more severely,The development of wastewater treatment technologies being relatively late in China, processing capacity in central western region can not compare with economically developed areas or town centers. Therefore this project, which focused on the unsatisfactory TN、TP removal effect in the No.1WWTP of Jinzhong city, was promoted to enhance the nitrogen and phosphorus removal effect.This study applies to upgrading existing secondary cities or small cities WWTPS,its ability to optimize nutrient removal in an area of land with little or no expansion of the premise.Step feed process uses raw water diversion methods and process control,Strengthening the effective use of denitrifying bacteria on raw water carbon source.This test uses AOAO process,running processes:water-stir before-before aeration-After stirring-after aeration-precipitation drainage-idle, Weekly amount of water to40L, the start of the reaction plus the original part of the water before stirring phase adding the remaining portion. It uses five kinds of flow distribution ratio (1:0,4:1,7:3,5:3,1:1) test,Comparing the flow distribution ratio of water effects.The result is showed:1:0distribution ratio has the worst biological denitrification, removal of nitrate being2.56mg/L; When Flow distribution ratio are4:1,7:3,5:3, the flow distribution with the distribution ratio being lower and biological nitrogen and phosphorus removal being the better,nitrate removal increasing0.91mg/L,4.32mg/L,5.80mg/L, improving the C/N ratio can be increased denitrification;When the flow distribution ratio of1:1, the insufficient nitrate amount affects the denitrification, nitrate removal reducing3.27mg/L while the flow distribution ratio of5:3; When the flow distribution are4:1,7:3,5:3, The effluent TN<15mg/L, TP<lmg/L, the rest of the indicators have reached the national emission standards A’s.Various indicators of water quality changes in Summer,the research on biological phosphorus removal in summer than in winter generally poor.This test uses a variety of methods for process debugging, analyzing the impact of various factors on biological phosphorus removal.The tests are showed: reducing SRT or extending the pre-mixing time is not obvious effects on biological phosphorus removal;Summer sewage containing less organic matter, external carbon source can enhance biological phosphorus removal, when sodium acetate dosage being400mg/L,and the effluent TP less than1mg/LL;Dosing chemical coagulant PAC in Precipitation, when the dosage is40mg/L,the Concentration of the effluent TP is less than1mg/L.