中文摘要：

以聚乙烯醇（PVA）包埋反硝化污泥,制得粒径为2.7、3.6 和4.8,mm 的3 种包埋微球,考察pH 值、温度和溶解氧（DO）对不同粒径微球的短程反硝化过程的影响.结果表明,微球在厌氧条件下对NO2^--N 的降解符合零级反应动力学模型,且随粒径的增大,NO2^--N 降解速率（以NO2^--N 计）由14.2,mg/（L·h）降至13.3,mg/（L·h）.与游离污泥相比,包埋微球对pH 值和温度的耐受范围显著扩大.在pH=5.7 时,粒径2.7、3.6 和4.8,mm 微球的NO2^--N比降解速率（以N/MLVSS 计）分别是游离污泥的1.5、1.8 和2.1 倍;而4,℃和48,℃时,不同粒径微球的NO2^--N 比降解速率差异并不显著.当DO 为0.5～0.7,mg/L 和1.0～1.2,mg/L 时,受到NO2^-和O2 传质的双重影响,粒径为3.6,mm 的微球表现出最高比降解速率（22.0 和16.2,mg/（g·h））,是相同条件下游离污泥的2.8 和8.0 倍.

英文摘要：

Denitrification sludge was entrapped in polyvinyl alcohol(PVA),three kinds of entrapping bead were obtained with diameters of 2.7,mm,3.6,mm,and 4.8,mm respectively. NO2--N was selected as denitrification nitrogen source,and the effects of pH value,temperature and dissolved oxygen(DO)on denitrification process under the condition of different diameters was studied. The results showed that NO2--N degradation of gel beads followedzero order kinetics model under anaerobic conditions,and as particle size increased,the degradation rate(calculated by NO2--N) gradually reduced from 14.2,to 13.3,mg/(L·h). Compared with free sludge,gel beads showed wider toler-ance range of pH value and temperature. At pH=5.7,the special degradation rates(calculated by N/MLVSS)of gel beads with diameter of 2.7,3.6 and 4.8 mm were 1.5,1.8 and 2.1 times of that of free sludge,respectively;meanwhile the influence of diameter on the denitrification rate was not significant when the temperatures are 4,℃and 48,℃. In the dual limitations of NO2--N and O2 mass transfer,when DO was 0.5-0.7 mg/L and 1.0-1.2 mg/L,the 3.6,mm gel bead showed the highest special degradation rates(22.0,and 16.2 mg/(g·h)),which were 2.8 and 8.0 times of that of the free sludge under the same conditions.