Rapid Culture Method Andperformance Of Suspended Filler Biofilmfacing To Phosphate Removal Andenrichment

Phosphorus was a kind of nonrenewable and scarce mineral resource.Phosphorus was an important source of phosphorus recovery and utilization in municipal sewage.It had been an important research topic in recent years to establish a wastewater treatment process with the goal of resource recovery and to remove and enrich phosphate from low-carbon and low-phosphorus wastewater after carbon recovery by using biofilm method.In view of the problems existing in the engineering application of biofilm removal/enrichment of phosphate,such as slow suspension packing membrane hanging speed,poor membrane hanging effect in the short term and long time needed for the enrichment of phosphor accumulating microorganisms.In this paper,the culture of suspended packing biofilm was carried out under various conditions,such as different inoculation mud source,organic load,anaerobic/aerobic alternating cycle,packing mixing mode and so on.A unified evaluation method was used to compare the removal effect of COD and NH₄⁺-N,phosphorus absorption and phosphorus release,EPS content and its composition distribution,and the average thickness of the biofilm with suspended filler obtained under different culture conditions.On this basis,the cultivation mode suitable for the adhesion and growth of phosphorous accumulating microorganisms on the suspended packing carrier was discussed,and the key factors affecting the fast film hanging of suspended packing were investigated.Combined with scanning electron microscope and high-throughput sequencing technology,the phosphate removal and enrichment performance of suspended packed phosphorus biofilm in mainstream phosphorus recovery process and the change of microbial community were discussed.Through the experiments,the following conclusions were drawn:?1?Different source of inoculation sludge,organic loads,anaerobic/aerobic alternation cycles,filling proportion and mixing mode of fillers had an impact on the cultivation of suspended filler biofilms.The effect of sludge source on suspension filler biofilm culture was small.The appropriate anaerobic/aerobic cycle could improve the adsorption and release of phosphorus and the film hanging effect.High organic load and slight impact of the packing mixture could shorten the suspension time and improve the suspension effect.?2?In this study by 40%of suspended packing volume filling ratio and the retainer was in a state of slight collision,four hours in anaerobic/4 hours in aerobic of alternate cycle,under the organic load of0.25kg?COD?/[kg?MLSS?·d],replace 25%of the water every 48 hours,could effectively shorten the time hanging membrane for 20 days,improve the effect of hanging membrane,biofilm thickness was 440.8?m,and had a better interpretation of the phosphorus absorption performance,phosphate removal rate was 53.2%,the amount of phosphorus release was 7.50 g/m³fillers.At this time,the total amount of EPS was 160.1mg·g-1ss,and the content of t-eps accounted for 53.4%,which was conducive to the adhesion of microorganisms on the surface of the carrier.?3?Suspended filler phosphorus biological membrane had good adaptability,could have good performance of phosphate removal and enrichment in the mainstream of phosphorus recovery processes,aerobic effluent concentration of phosphate was less than 0.5 mg/L,and could get 63 mg/L phosphate solution.And the phosphor accumulating bacteria in the biofilm could be further enriched and cultured in the process of operation...