低碳氮比畜禽粪水厌氧消化液短程硝化脱氮试验研究

针对畜禽粪水厌氧消化液存在低C/N、后续可生化性差等问题,提出利用短程硝化反硝化技术处理高氨氮畜禽粪水厌氧消化液。结果表明:在(29±1)℃条件下,通过调节曝气量控制DO在0.6~0.9 mg·L~(-1)之间,接种厌氧氨氧化颗粒污泥可快速实现短程硝化反硝化;之后在恒定曝气量下使反应器内DO为0.1~2.88 mg·L~(-1)时,在处理高氨氮粪水过程中,通过对比四组不同pH和游离氨(FA)发现,当pH=8、FA=18 mg·L~(-1)左右时更利于亚硝化菌的优势竞争并可长期稳定实现短程硝化反硝化;应用MPN法测得氨氧化菌(AOB)和亚硝酸氧化菌(NOB)数量之比为600∶1。SBR反应器稳定运行期间COD负荷和氨氮负荷分别为2.0~3.5 kg·m~(-3)·d~(-1)和0.6~0.8 kg·m~(-3)·d~(-1),COD去除率为63%~71%,NH~+_4-N去除率在94.9%以上,NO-2-N积累率(NAR)达到94.25%以上。

Feasibility study on the treatment of low C/N digested animal manure with shortcut nitrification-denitrification process

Traditional digested animal manure has some problems such as low C/N and poor biodegradability, thus shortcut nitrification-denitrification was suggested to deal with the manure. Our study showed that by controlling DO concentration within the range of 0.6~0.9 mg·L-1, seeding the reactor with anaerobic ammonia oxidation granulated sludge to achieve a stable nitrite accumulation under(29±1)℃could realize partial nitrification-denitrification quickly. Then we kept DO concentration within the range of 0.1~2.88 mg·L-1 under constant aeration, and the best nitrite accumulation and NH+4-N removal efficiency was observed when pH at 8 and FA at 18 mg·L-1, a condition more conducive to nitrite bacteria for competitive advantage and long-term stability to achieve shortcut nitrification-denitrification, through the comparison of four different groups. Moreover, the quantitative ratio of ammonia-oxidizing bacteria(AOB)to nitrite-oxidizing bacteria (NOB)was 600:1. During the stabilized flow of the anaerobic digestion fluid into the SBR, the loading rates of COD and NH+4-N were 2.0~3.5 kg·m-3·d-1 and 0.6~0.8 kg·m-3·d-1, with the removal rates of COD and NH+4-N for 63%~71%and 94.9%, respectively. And the nitrite accu-mulation rate reached more than 94.25%.