Screening And Characterization Of High-efficiency Polyphosphate Denitrifying Bacteria

In recent years,the amount of waste water containing nitrogen and phosphorus has been increasing year by year.Some of these are incomplete treatment,or have not dealt with direct emissions,causing surface water pollution and serious eutrophication.Synchronous poly-phosphorus denitrification technology is a new technology for removing phosphorus and nitrogen from water pollution organisms.At present,research on simultaneous phosphorus and denitrification technology has gradually become a hot spot in biological management.Synchronous poly-phosphorus denitrification technology enables phosphorus removal and denitrification energy to be carried out in the same reactor,which has many advantages over traditional biological phosphorus-based denitrification,reducing wastewater treatment costs and improving wastewater treatment efficiency.The research on phosphorus and denitrifying bacteria at home and abroad is still in the laboratory stage and the practical application is less.Research on phosphorus and denitrifying bacteria is of great significance to the application of biological treatment of water pollution.In this study,samples were taken from the oxidation ponds of the wastewater treatment system of Anhui Lujian Breeding Co.,Ltd.Through enrichment,domestication,primary screening and rescreening,a highly efficient phosphorus-and denitrifying bacteria capable of efficiently removing ammonia nitrogen,total phosphorus and total nitrogen were obtained.For DL-16 by morphological,physiological and biochemical experiments,and 16S rRNA determination and homology comparison,after repeated analysis,it was determined that DL-16 is Pseudomonas aeruginosa.This article focuses on the growth and dephosphorylation characteristics of strain DL-16.By changing the carbon-nitrogen ratio,carbon source,pH,different inoculum volume and temperature of the culture medium,the growth conditions of the strains were investigated,and the optimal conditions of polyphosphorus denitrification were investigated.The results showed that the optimal conditions of strain DL-16 were:carbon/nitrogen ratio was 10,pH was 9,inoculum was 5%,carbon source was sodium citrate,temperature was 28?,growth of strain DL-16 and phosphorus and nitrogen removal The pH and temperature are more sensitive but have a certain degree of tolerance.This paper also studied the treatment of actual high ammonia nitrogen swine wastewater by strain DL-16.The results showed that the concentration of ammonia nitrogen,total nitrogen,COD and total phosphorus in the farm wastewater decreased significantly.The concentrations of NH4+-N,COD,TN and TP in the wastewater from the initial 48 h were from the initial 300.97 mg·L-1,3588 mg·L-1,782.75 mg·L-1 and 35.64 mg·L-1 decreased to 96.53 mg·L-1,288 mg-L-1,241.08 mg·L-1,and 5.30 mg·L-1,respectively.67.93%,91.97%,69.20%,85.13%.In the actual treatment of landscape water,the concentration of NH4+-N,COD,TN and TP in landscape water from the initial 48h from the initial 249.69 mg·L-1,278 mg·L-1,750.14 mg·L-1,34.64 mg·L-1 dropped to 33.28 mg·L-1,31.57 mg·L-1,208.48 mg·L-1,and 5.65 mg·L-1 removal rate reached 86.67%,88.66%,72.21%,and 84.13%respectively..From the above experimental results,it can be seen that strain DL-16 has significant decontamination effect on pig farm wastewater and landscape water,especially the removal effect of total phosphorus in wastewater is very obvious,indicating that the actual polyphosphate denitrification effect of bacteria species is good,in water organisms Phosphorus and nitrogen removal have good application prospects,and have potential application value in the biological treatment of polluted water.