| In recent years, the poultry emissions and the massive waste water from the flushing breeding farm were mostly in our country haven't been proper managed and recycled but to let directly, which engendered serious pollution to surroundings. Therefor, there is a key technology called UASB treating technology which can band environmental-protection and energy-recycle together efficiently. The aim of experiment was to deal with the waste water which from Sichuan agricultural university poultry breeding farm, by using the UASB(upflow anaerobic sludge blanket) experimental equipment. Study on its start-up period and anaerobic oxidation of ammonia process. The results were summarized as follows:1. It spent 122 days to start-up UASB reactor by using poultry breeding waste water. there were four stages in the starting process: the sludge activity revivification, the preliminary starting, the loading increasing and the loading moving.In the sludge revivification stage, there was a layer of scum which about 50mm at the assembling air-chamber of three-phase separator. The scum had flowed along with effluent out of the reactor slowly, which leaded the COD value higher than influent water. A week later, the COD value in effluent was lower than in enter liquid with the ratio of removal was 25 percent; the flocculent sludge appeared at the base of reactor, meanwhile a few air bubbles were observed.It was consumed 38 days to Preliminary start-up. It's didn't adapt to the waste water obviously in initial stage of preliminary starting(1-12d), in which the quality of effluent was worsen with the acidification seriously by pH value droped to 6.5. In intermediate period(13-21d), gradually, the running was tended to stable by throwing alkali into the reactor. In the last stage of preliminary start-up, the ratio of removal rose to 78 percent, anaerobic sludge multiplies more fast and exiguous particles appeared.The period of enhancing load was a transitional stage before the reactor running stably. The cubage loading rose from 2.52kg COD/m3.d to 15 kg COD/m3.d gradually. Because the anaerobic bacterium multiplied very slowly, 64 days was consumed at this stage; The reactor ran stable with the pH value of effluent stabled around 7.0, so it's no need to throw alkali any more; there was a common phenomenon that the ratio of COD's removal in first day had a little lower than the last time of loading running, but it would had risen in successive three days. With enhancement of loading in reactor, the activity of sludge was strengthen unceasingly, and it produced more air by sludge. In the intermediate stage of enhancing loading, the phenomenon of losing flocculent sludge had disappeared; anaerobic bacterium multiplies rapidly, and the thickness of sludge bed had increased unceasingly. The volume of sludge bed was about 50 percent of all reactor when the last stage of enhancing loading coming; the sludge was mostly granulated. The ratio of COD removal maintained above 75 percent.In the bearing load stage, the cubage load had been enhanced to 22.5kgCOD/m3.d. The ratio of COD removal droped to 65 percent, at the same time, pH value of effluent droped to 6.5. After had been running 10 days by supplying more alkali, the ratio of COD removal could stabilize at 75 percent finally. But pH value of effluent was under 7.0 and it needed to supply appropriate alkali every day to keep the environment which adapted to multiply anaerobic bacterium in the reactor.2. There were so many factors could be affect the running of reactor such as different temperature, different cubage loading of COD and different pH value. Known by the experiment results: in the UASB reactor, 35℃was the most appropriate temperature, 7.0 was the best pH value. When the cubage loading was 10kgCOD/m3·d, the reactor had been in a ideal condition to treat the waste water.3. The experiment of ammonia oxidation in anaerobic condition consumed 112 days; According to the ammoniac-nitrogen concentration of influent, the process of running composed of divided three stages: period of adaptation,running stage with high concentration,running stage with low concentration.In the period of adaptation, the ammoniac-nitrogen average concentration of influent was approximately 150mg/L; the concentration of effluent was very close to the influent's, sometimes the concentration of effluent was slightly higher than influent's, and the ammoniac-nitrogen hadn't been removed in the reactor. The average ratio of removal about COD and NO2--N was 46.7 percent and 29.2 percent respectively.The concentration of ammoniac-nitrogen changed from 230mg/L to 270mg/L in the high concentration stage. The average of it was 245mg/L, the concentration of ammoniac-nitrogen in effluent was lower than in influent's. There was the period of ammonia-oxidation in anaerobic condition. The cubage loading of ammoniac-nitrogen had raised to 0.85kg/m3 d from 0.45kg/m3 d gradually, and the average ratio of removal had risen to 10.2 percent from 6.5 percent also; The average ratio of removal about COD and NO2--N reached 73.1 percent and 54.9 percent.In the low concentration stage, the concentration of ammoniac-nitrogen in influent was adjusted to 150mg/L again, and the cubage loading of it maintained around 1.15kg/m3·d. The ratio of removal had risen to 28.1 percent from 10.6 percent. After the three stages, the starting of response about ammoniac-oxidation in anaerobic condition had been finished basically.During the running period, the response of ammonia-oxidation in anaerobic condition wasn't exist at the beginning time, but it reached about 15.9 percent in the middle stage, and it rose gradually to 65 percent from 28 percent in the middle-last stage. Bacterium of ammonia-oxidation in anaerobic condition had been enriched in great degree in the reactor.
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