Enrichment And Cultivation Of Phosphorusrich Biofilms Based On Phosphorus Recovery

Due to the development of industry,phosphorus mineral resources are becoming less and less and the excessive discharge of phosphorus causes environmental pollution.However,the process of traditional wastewater treatment plant only considers the removal of phosphorus,so it is an important subject for the study of phosphorus synchronic removal and recovery from the future wastewater treatment plants.Low phosphorus content,but domestic sewerage based on phosphorus recovery struvite method,the higher the initial concentration of phosphorus produce the higher recovery efficiency.Thus,in order to achieve energy saving and efficient recycling of phosphorus,how to improve the recovery liquid concentration become a research hot issue.The research group used biofilm method to remove and recycle phosphorus in urban wastewater.In this paper,our study adopt two kinds of biofilm domestication method,explore the phosphorus removal performance,phosphorus recovery ability as well as the change of the microbial population.Aim is to obtain rapid absorption of phosphorus,effective phosphorus release biofilms of microbe culture conditions.Scheme1,a low phosphorus load(4 h aerobic,4 h anaerobic,phosphorus concentration of 5 mg/L,the water load of 0.03kg/?m·d?^-1)for domestication of phosphorus biofilm.Both scheme,high phosphorus load(initial period is 8 h,phosphorus load 15 mg/L,the water rising to cycle for 4 h,phosphorus concentration of 20 mg/L,load by 0.09 kg/?m·d?^-11 rose to 0.24 kg/?m·d?^-1)on phosphorus biofilm domesticated.After stable operation,the effluent index can meet the effluent A standard.When the second load was increased from 0.18kg/?m·d?^-11 to 0.24kg/?m·d?^-1,good oxygen P failed to meet the standard.Scheme 2 is superior to scheme 1 in operating cycle,both phosphorus release rate and phosphorus uptake rate.At the time of recycling,the recovery concentration was not increased when the recovery concentration was 30mg/L at 16d,and the concentration of the recovery solution increased to about 50mg/L,and then remained basically unchanged.At the same time,in the process of biological film domestication,the diversity of bacteria decreased.At the level of"phylum"and"family",the sample of the solution was dominated by Proteobacteria and Rhodocyclaceae respectively.Proteobacteria increased from 47%to 58%,and Rhodocyclaceae increased from 17.9%to 28.9%.And the two clay samples were mainly Proteobacteria and unclassified_-Proteobacteria in the"gate"and"branch"levels.Proteobacteria increased from 50%to 83.4%.Unclassified-proteobacteria increased from 6.27%to 35%.The second division,Rhodocyclaceae,increased from 11.8%to 20%.The study found that compared the period of aerobic segment with organic matter,the microorganism showed higher ability to absorb phosphorus and release phosphorus when there was no organic matter in the aerobic segment.