Study On Characteristic Of Denitrification Phosphorus Removal By Submerged Membrane Sequencing Batch BioReactor

Denitrification phosphorus removal system can take full advantage of the carbon in wastewater to be conducted for denitrification,;nitrate at the same time can be used as a electronic receptor for accumulation of phosphorus,which can bring lots of advantages,such as simplifying the process,saving and reducing the product of sludge,as well as the reduction of greenhouse gas CO₂ emissions,it is a sustainable clean wastewater treatment process.This paper utilized artificial Submerged membrane Sequencing Batch bioreactor(SMSBR),and adopted two phases of training domesticated mode:anaerobic-aerobic and anaerobic-precipitation water change-anoxic,which achieve a good effect of nitrogen and phosphorus removal simultaneously.Based on the successful cultivation of domesticated activated sludge system,we developed research on the effects of denitrification phosphorus system factors,denitrification phosphorus accumulating organisms and its metabolic mechanism and dynamic model,main research results are as follows:(1)denitrification phosphorus removal system exists reasonable time for phosphorus release and uptake,which has relationship with carbon and nitrate concentration in the system,the quantity of PHB,glycogen and poly phosphate,the study showed that the system anaerobic and anoxic time maintained reasonablely at 2 and 3 hours relatively,long time on the effective anaerobic phosphorus release does not help,but will increase HRT,long time will lead to anoxic endogenous phosphorus release.(2)the system could be contrled best removal level under such condition: COD_cr250mg/L,NO₃^--N55mg/L,SRT20～30d.(3)under best operating conditions the pollutant removal efficiency can achieve above 95%,compared with traditional biological nitrogen and phosphorus removal process,it can save 58 pencent of the carbon source and 30 pencent of the aeration capacity,but should pay attention to the control of reaction conditions,in particular the control of pH in alkaline conditions to run,when to sludge monitoring activity to decline,through short-term aeration Sludge resume activity. (4)under stable operation the changes of pH and phosphorus cycle curves have great relevance,therefore using online pH to achieve automatic control denitrification phosphorus removal process will have a certain feasibility.(5)experiment showed that denitrifying bacteria Phosphorus running in anaerobic-anoxic environment can use O₂,NO₃^--N,NO₂^--N as electronic receptor for the conduct of absorption of phosphorus,but aerobic phosphorus uptaken is higer than anoxic conditions.The value is relatively 13.12 and 11.72 mg PO₄^3--P·g^-1SS·h^-1. when concentration of NO₂^--N is above 25mg/L,it become a Inhibition for phosphorus uptake.(6)microbial cycle activity indicators research found that anaerobic sludge concentration,volatile components and interior Specific Oxygen Uptake Rate(SOUR) is higer than anoxic phase,the content of phosphorus in the slugde at the end of anoxic increased 10.35 percent,showing the capacity for phosphorus uptake more than physiological phosphorus absorption capacity.