| About one third wastewater treatment plants had the crisis of carbon source shortage in our nation. Although chemical phosphorus removal process was used in some plants, nitrgon and phosphorus could not meet the discharge standard simultaneously. For the problem of shortage of carbon resource in the sewage, primary sludge would be used as substrate to develop carbon resource with two-stage complete mixing hydrolysis and acidification process. The temperature of hydrolysis and acidification reactor was controlled by thermostatic waterbath and the temperature was 35℃. Effects of HRT,SRT and sludge recycle ratio on hydrolysis and acidification of primary sludge were studied. The results of research showed that when the HRT is in the scope of 32 to 36 hours, the process had a good VFAs cumulative effect and the soluable COD (SCOD) of effluents is 1090~1180mg/L, in the codition of SRT was 3 days and sludge recycle ratio was 1; when the SRT is between 4 to 7days, acidogenic bacteria and methanogenic bacteria could be separated and the process had a good hydrolysis and acidification effect, The SCOD of the effluents was in the scope of 980~1180 mg/L, when the codition of HRT is 32 hours and sludge recycle ratio is 1; recycle ratio also had an improtant effect on hydrolysis and acidification of primary sludge, when HRT and SRT were controlled to 32 hours and 4 day, the process had a good hydrolysis and acidification effect when sludge recycle ratio was between 0.75 to 1.The aim of developing carbon resource was improving the nitrogen and phosphrous removal effect of biological nutrient removal (BNR) process. Effects of dosing hydrolysate (process'effluents is rich in VFAs) on denitrification rate of denitridiers and phosphorus release and phosphorus uptake rate of PAOs (phosphorus accumulating organisms) were be studied by sequencing bath reactor. The studied results showed that dosing hydrolysate to the BNR process could improve nitrogen and phosphorus removal rate remarkablely, in the sequencing bath reactor of denitrification, as the concentration of carbon resource reducing, the denitrification rate was changing by stages. When the hydrolysed dosage was 30 mg/L (measured by TOC), the average dentrification rate of the denitrifier was 0.367mgNO3-N/mgVSS.d while carbon consumption rate was 0.713mgTOC/mgVSS.d at the first stage; phosphorus accumulating organisms have the same phosphorus release potential in the active sludge, the more carbon resource in the sewage, the stronger phosphorus release potential would be stimulated. The more hydrolysate addition in the sewage, the quicker phosphorus release rate PAOs have. When hydrolysate dosage was 30mg/L (measured by TOC), the average phosphorus release rate of PAOs is 0.137mgP/mgVSS.d. Carbon resource rich in the sewage or not had a less impact on the average aerobic phosphorus uptake rate, but a strong effect on the sustained time of phosphorus uptake process. When the sewage was rich in carbon resource, phosphorus uptake process of PAOs sustained a long time, and vice versa. The average phosphorus uptake rate of PAOs was between 0.129 to 0.160mgP/mgVSS.d in the sequecing bath reactor, therefore PAOs had strong phosphorus uptake capacity. Organic matters uptaked by denitrifier and PAOs were different, such as the conditions that dosage of hydrolysate was 30mg/L(measured by TOC), the percentage of organic carbon that could be used by denitrifier was 75.7%, and uptaked by PAOs was 57.4%. When dosing hydrolysate to the anaerobic origin of A/A/O (anaerobic-anoxic-oxic) process and the dosage is 36mg/L (measured by TOC) , the nutrient parameter of the effluents were as follows, TN is 14.18 mg/L and TP is 0.4mg/L, which meet the first level A criteria specified in the Discharge standard of pollutants for municipal wastewater treatment plant (GB18918-2002).
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