| Organics, main pollutant in municipal sewage, are important carbon and energy source for growth and metabolism of activated sludge, and they have been also playing a significant role in changing the treatment effects of activated sludge system. The research has mearsured the content of some main organics in the influent of Longwangzui WWTP, found their relations with the treatment effects of the pilot plant system and components in the influent of ASM model, and reached some main results below:(1) Reversed-Phase HPLC has been verified as a method to measure the content of VFA of low concentration in municipal sewage accurately. The research has measured the content of VFA in the influent of Longwangzui WWTP, and the result has demonstrated that the content of VFA in the influent enjoyed seasonal variation, stabilizing above25mg/L and between1to10mg/L during April to May and July to December respectively. Most of the time, VFA in the influent only contained acetic acid, but propionic acid, n-butyric acid and isobutyric acid could also be detected sometimes. And the sum of the content of acetic acid and propionic acid could take up90%of total VFA. The proportion taken up by VFA of total COD also enjoyed seasonal variation, with10%-11%in spring,3%-5%in summer and1%-3%in winter.(2) The content of VFA in the influent of Longwangzui WWTP enjoyed good positive relevance with the removal rate of TP, phosphate and COD of the pilot plant system. And propionic acid/acetic acid ratio in VFA had significant influence on anaerobic phosphorus release, anoxic phosphorus uptake and phosphorus removal rate. Intensity of anaerobic phosphorus release decreased with the increase of propionic acid/acetic acid ratio, and the absorption rate of COD in anaerobic phase increased and then decreased with the increase of propionic acid/acetic acid ratio, and reached maximum value when propionic acid/acetic acid ratio reached2.(3) The reseach has measured the content of saccharides, protein and oil in the influent of Longwangzui WWTP, and the result has demonstrated that saccharides, protein and oil took up3%-20%,19%-69%and3%~13%of total COD respectively, and dissoluble saccharides and protein took up9%and32%of total saccharides and protein in average respectively.(4) The reseach has found the relations between dissoluble saccharides ST, insoluble saccharides XT, dissoluble protein SD, insoluble protein XD, inert dissoluble protein ID, oil XF and SS, SI, XS, XI, and summarized the following predictor formula:SS=0.95(SA+ST+SD-ID)SI=ID+2.64XS=0.9541(XT+XD+XF+SD')+22.751XI=CTCOD-(SA+ST+SD)-0.9541(XT+XD+XF)-25.39(5) The transfer patterns of saccharides and protein in activated sludge system of the pilot plant were different in different working condition. Under the working condition of two stage step-feed biological nitrogen and phosphorous removal, AO phosphorous removal and tapered aeration, saccharides has been consumed completely in the anaerobic phase, but protein has also partly been consumed in anoxic phase. The removal rate of saccharides in this three working condition were basicly the same, and the removal rate of protein in the working condition of two stage step-feed biological nitrogen and phosphorous removal was relatively higher than that of the other two working conditions. Under the working condition of adding carbon source50mg/L, microorganisms in the system could not adapt to the newly adding carbon source, so they could ont use it, then, the concentration of saccharides and protein in the cells of pilot plant were relatively high, and the removal rate of nitrogen has not been improved. And under the working condition of adding carbon source100mg/L, microorganisms in the system started to adapt to the new carbon source, the removal rate of saccharides, protein and nitrogen had all been improved. The transfer and degradation of saccharides and protein were related to the water quality of the influent, the working condition and other factors. |
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