摘要
Urine is characterized by high salinity, complex components, and significant transformationduring long-termstorage process. Therefore, the mechanism of transformation in term ofinorganic substances and organic matters were investigated, and the effect of 3 different pretreatment processes, i.e., acidification by H2SO4, UF by ceramic membrane, and absorption by activated carbon (AC), were studied.It was found that the key process of transformation was urea hydrolysis and the inorganic coprecipitation phenomenon, while the transformation of phosphate precipitation to struvite was found with the increase of ammonia nitrogen concentration from 1365 to 2755mg/L during urine storage. The acidification showed significant urine stabilizationability by inhibiting urea hydrolysis; while ceramic membrane and AC promoted the urea hydrolysis, and AC could effectively adsorb nitrogen. The DOM composition also varied significantly duringthe urine storage process byfluorescence spectrum: the increase of E280/E472, A275~295, E254/E365 and E300/E400 in concentrated H2SO4 pretreatment group showed that the concentration of hydrophobic and small molecular organics of DOM were increased, whilethe decrease of UV254 and A350~400 also confirmed the decrease of aromatic organics. The UF and absorption process showed significant removal efficiency for DOM, however, ceramic membrane showed higher removal efficiency on urea, while the removal rate of aromatic organic compounds was higher by AC. This work systematically elucidatesthe process and mechanismof properties variation during the urine storage process, and demonstrates the influence of pretreatment technologies, which could guide the technical scheme selection for the source-separated urine treatment.