Sewage Sludge Anaerobic Fermentation To Produce Biogas Coupling In Phosphorus Recovering Technology

In recent years, it is found that the sludge anaerobic fermentation process can release lots of phosphate that can be recycled, so the specific phosphorus release during the sludge anaerobic fermentation process and the achieved recovering method is particularly important.Selecting the controlling factors temperature in the sludge anaerobic fermentation(TS=10%)process to explore the effects of temperature on the production of methane gas and the phosphorus release law. The recovering phosphorus from fermented liquid by aeration to remove CO2 make the p H improve and dosing Mg O, analysis the precipitate by SEM and XRD. At last, analysis the microbial structure under different temperature by DGGE and T-RFLP.Main results are as follows:(1)By excess sludge anaerobic fermentation experiments, it is concluded that at room temperature,38?,45? and 55? temperature condition, the cumulative biogas production rate corresponding as 66 m L/g-VS,204 m L/g-VS,632 m L/g-VS and 392 m L/g-VS. The PO43--P concentration of fermented liquid from 34mg/L can reach their maximum concentration respectively as 114.14mg/L,72.22mg/L,92.90mg/L and 92.90 mg/L. May be due to the fermented liquid of NH4+-N and phosphorus transformation of state conditions, so in the end the PO43--P concentration in the fermented liquid has reduced.(2)After phosphorus recovering experiment, the results show that the recovery rate of the four kinds of fermented liquid is 85.2%,92.3%,86.5% and 85.2%.By SEM,the precipitum is struvite and mainly is short ridge block crystal. By the XRD, the percentage of struvite crystals in the precipitum is different,the fermented liquid of 38 ? and 45 ? recycling products crystal structure neat and have the higher percentage of the magnesium ammonium phosphate salt. Analysis the fermented liquid afte the phosphorus recovering experiment compared with the raw liquid by Three-dimensional fluorescence. The higher content of soluble organic matter, the more easy to make higher phosphorus residues after reaction, and aromatic high protein concentration affects the shape of struvite crystals, a short edge block.(3) Analysis the microbial diversity of the fermention under different temperature by DGGE and T-RFLP.Analyzed the advantage of methanogens strain distribution under different temperature, different temperature response group contains bacteria, microbial diversity is also different.