| Along with the great development of scaled and intensism livestock breeding,the livestock waste water has become a third pollution resource after the the industrial waste and life waste,even the most serious one.The content of organics,N,P and animalcule is very high.If we pour them directly into the water or store them improperly,when they are washed into water,they will cause serious pollution of surface water or ground water quality. Academicians both at home and aboard have done a lot of research and find out anaerobic treatment process is the key technology in get rid of waste on the livestock farm. UASB(Upflow Anaerobic Sludge Blanket Reactor) the most wide-used technology,but the nitrogen and phosphorus removal is not perfect.In this article,we will discuss effect of the degradation of COD and the removal of the phosphorus and nitrogen by comparing the startup and the result respective in UASB and UAFSB in different conditions. The results are summarized in the following:(1) It's feasible to start-up UASB and UAFSB using livestock wastewater.After 54 days' acclimation of the inoculated with activated sludge,the consistency of COD can increase from 800mg/L to 5000mg/L and the removal rate can almost keep more than 90%.Both of them reach the predicted aims.Doping granular activated carbon into the sludge can shorten the time of the reactor's start-up and increase the shock resistant.(2) The pH and temperature has an obvious influence on the removal in UASB.The best pH is 7.5,among which the effect of removal of COD and TP is better;The best temperature is from 32℃to 38℃,among which the effect of removal of COD and TP is better;The HRT is not the longer,the better.The better HRT was in range of the 44 hour to 48 hour,the quality of effluent is satisfiable by the UASB.(3) The pH has an obvious influence on the removal in UASFB.The best pH is between 7.5 and 8.5,among which the effect of removal of COD and TP is better.The ratio of removal of COD cart be more than 80%,even to 95%,and TP to 83%.At the same time,the total nitrogen can be got rid of to the degree.(4) Temperature may influence removal effect.Although the ratio of removal of COD,TN and TD is stable,if the reactor is in the temperature was from 34℃to 38℃,the degradation of COD(chemical oxygen demand) and the removal of the phosphorus and nitrogen will be better.Along with the increase of temperature,there will be little float,and the ratio of COD removal will be about 90%,TP about 80%and TN about 30%.if considering the removal of C,N and P,the temperature should be about 38,especially which has advance in saving energy and effect.(5) Dissolved oxygen has an obvious influence on the removal in UASFB.The higher DO, the lower the removal of COD and TP.So when the DO was in range of the 0.2mg/L to 0.4mg/L,UAFSB can work better and the removal ratio of COD and TP can be 93%and 90%. As for TN,the removal of the nitrogen will be better when DO is about 0.6mg/L.(6) When we use UASFB to deal with the livestock waste,debug tool can work well if the pH is between 7.5 to 8.0 and the temperature between 34 to 38,together with dissolved oxygen between 0.2 to 0.4.UAFSB has made great progress in the degradation of N and P, compared with UASB.The removel of the phosphorus can reach 80%or more.
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