| With the development of mechanized feedlot, environmental pollution that it(such as the hoggery) brought about has become more and more serious. It is difficult to treat piggery wastewater due to higher organic waste containedin it. However, at present, the large amount of wastewater from the poultry breeding is mostly discharged directly without appropriate treatment, so it produces a comparative pollution to the environment. This research adopts ASBR-SBR craft to deal with piggery wastewater. Firstly, piggery wastewater is treated with ASBR anaerobic reactor. Then the start-up of the reactor and operation efficiency is studied. SBR (sequencing batch reactor) as follow-up of anaerobic craft, afterward, ASBR anaerobically digested effluent of piggery wastewater is treated with SBR. The overall treatment result of the security system can reach the discharge standard. This thesis researches the efficiencies of ASBR(anaerobic sequencing batch reactor) used in treating piggery wastewater caused by different influenced factors. Study follow-up craft operating mode terms of SBR: is it feasible that ASBR-SBR craft deal with piggery wastewater and offer the basis for engineering design. The results of the study show that:①Piggery wastewater after treatment of ASBR-SBR system, COD removal efficiency is about 96%, NH3-N removal efficiency is about 87%. The COD of effluent was mostly under 400mg/L, the NH3-N of effluent was under 70mg/L, the treated wastewater could meet the discharge standard of pollutants..②Use the granular sludge exerted great effects on the start-up for the ASBR. After more than 70 days, the final organic loading was 7.5 kgCOD/(m3·d). The average COD and BOD5 removal efficiency were respectively 80.91% and 93.72% when the organic loading was between 5 and 7.5kgCOD/(m3·d). In the normal runtime of ASBR, the rate of methane output was between 1.0 and 2.1m3/(m3?d), the maximal rate of one-day output can be reached to 2.8m3/(m3?d).③The VFA of effluent was fluctuated between 200 and 500mg/L during the experimental process. On the 38th day, the VFA of effluent was reached to 1100 mg/L due to the OLR over increase. After adding NaHCO3 properly, the VFA of effluent was gradually reduced to 400mg/L. With the rising of OLR, the pH of effluent also declined. But after few days, it can be stabilized mostly without obvious acidification phenomena.④Through the comparisons of different run condition of each unit, find the best cycle of SBR to treat piggery wastewate: Under the operation cycle of SBR is 12h, MLSS load≤0.51kgCOD/(kgMLSS·d) and 0.14kg NH4+-N/(kgMLSS·d). Piggery wastewater after treatment of SBR system, overall COD removal efficiencies is 80%~85%, NH4+-N removal efficiencies is more than 85%.⑤When pH of the testing water in SBR reactor is from 7 to 8, the pollutants removal efficiencies are jarless. Advancing the anoxic unit can make the change of pH in the reactor more gently than it in the traditional SBR. The anterior unit also can use the abundance carbon to wipe the pollutants off quickly.⑥The removal efficiencies of NH4+-N is jarless when temperature stays at 25℃, it drops quickly when the temperature is lower than 15℃. While the removal efficiencies of COD is jarless in the whole process. |
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