摘要
采用传统推流式连续流工艺处理校园生活污水．考察了常温和低温时DO对污泥膨胀的影响。试验结果显示：常温23℃将DO从正常的2mg／L以上降低至0．5mg／L，引发了污泥沉降性的恶化，SVI值从150mL／g升高到175mL／g左右，这时出水非常清澈，并且在一个月的运行中，系统稳定保持低氧丝状菌微膨胀；低温15℃时，降低DO引发了严重的污泥膨胀，SVI值达到350mL／g以上}为控制污泥膨胀，升温至23～25℃，但维持DO在0．5～1mg／L，SVI值下降到200mL／g，系统再一次达到稳定的低氧丝状菌微膨胀，这期间COD去除率不受影响．保持在80％以上。可见，不要求脱氮的污水处理厂在春夏秋季，可以考虑在低DO条件下运行，不仅不会发生过大的污泥膨胀，还可以大量节约供氧能耗。
Traditional plug flow continuous process was taken to treat the campus waste water, for the purpose of preventing sludge bulking and saving energy by providing oxygen supply strategy for wastewater treatment plants in different seasons, effect of DO on sludge bulking was studied. The experiments indicate that under the condition of normal temperature of 23 ℃, reduced DO from above 2 mg/L to 0.5 mg/L caused the sludge settlement ability to become worse, and SVI value increased from 150 mL/g to about 175 mL/g. The system maintained the limited filamentous sludge bulking for a month, and the effluent was very clear. Under the condition of low temperature of 15℃, reduced DO caused serious sludge bulking, and SVI value reached above 350 mL/g. In order to control sludge bulking, the temperature was increased to 23-25 ℃, DO remained 0.5-1 mg/L, and SVI value decreased to 200 mL/g, then the system was under the condition of low DO and maintained the limited filamentous sludge bulking again. The COD remow al rate was not influenced and remained above 80%. Therefore, the waste water treatment plants which do not need to remove nitrogen could be operated under low DO condition so as to save much energy for the oxygen supply without worrying about sludge bulking.
出处
《安全与环境工程》
CAS
2006年第4期39-42,共4页
Safety and Environmental Engineering
基金
国家自然科学基金重大国际合作项目(50521140075)
北京市自然科学基金项目(8062006)资助
关键词
低氧
丝状菌微膨胀
节能
温度
low DO
limited sludge bulking
save energy
temperature
