摘要
餐厨废水具有高NH_4^+-N、低C/N的特性,采用传统生物脱氮工艺需要消耗大量碳源,而采用短程硝化-厌氧氨氧化组合工艺可以较好地处理此类废水,通过控制DO浓度来实现废水半短程硝化可为组合工艺提供进水条件。采用自制SBR反应器,控制ρ(DO)在0.5~0.6 mg/L,温度为(30±1)℃,可实现废水的半短程硝化,NO_2^--N累积率可达90%以上,出水n(NO_2^--N)∶n(NH_4^+-N)约为1,系统COD去除率维持在65%左右。系统稳定后对1个周期内的系统进行观察,发现0~1 h内系统中COD得到迅速降解,1~8 h内COD降解速率放缓,出水NO_2^--N累积,较低的DO浓度可有效地限制NOB的活性,反应周期内NO_3^--N浓度基本处于较低水平。当DO浓度过低时,系统中AOB和NOB同时受到抑制,氧化一定量的NH_4^+-N所需时间更长;ρ(DO)浓度高于1.5 mg/L时,NOB活性逐步恢复,系统中NO_3^--N浓度增加。因此,通过控制DO浓度实现低C/N餐厨废水半短程硝化是可行的,可为后续试验创造条件。
According to the characteristics of food wastewater with high NH_4~＋-N and low C/N ratio,the traditional biological denitrification process required a large quantity of carbon sources,and the short-cut nitrification-anaerobic ammonium oxidation process could remove pollutants better in this kind of wastewater.The partial nitrification of wastewater was achieved by controlling DO concentration.Using the self-made SBR reactor could achieve partial nitrification of wastewater with DO concentration of 0.5~0.6 mg/L and temperature of（30±1）℃.The NO_2^--N accumulation rate in the reactor was higher than 90%,the molar ratio of NO_2^--N to NH_4~＋-N in the effluent were about 1,and the COD removal rate was about 65%.After the system was stable,it was found that in 0 to 1 hour,COD in the system was rapidly degraded,but in 1 to 8 hour,COD degradation rate slowed down,the effluent NO_2^--N got accumulated.The lower DO concentration was better to limit the activity of NOB.The NO_3^--N concentration in the reaction cycle was at low level.When DO concentration was too low,the system AOB and NOB were inhibited,and oxidation of NH_4~＋-N took longer.When DO concentration was higher than 1.5 mg/L,the activity of NOB gradually was recovered,and NO_3^--N concentration got increased.Therefore,controlling DO concentration was effective in achieving partial nitrification of low C/N food wastewater,it could provide conditions for the follow-up experiments.
出处
《环境工程》
CAS
CSCD
北大核心
2017年第12期20-24,共5页
Environmental Engineering
基金
国家科技支撑计划项目(2012BAC18B01-2)
江苏省科技支撑计划项目(BK20130126)
关键词
餐厨废水
低C/N
短程硝化
亚硝化率
food wastewater
low C/N
short-cut nitrification
nitrification rate
