Study on the Short-cut Nitrification and
Denitrification in Coke Plant Wastewater Treatment by Using
Submerged Membrane Sequencing Batch Reactor

LI Chun-jie1,GENG Yan2,ZHOU Qi2,GU
Guo-wei2
(1.School of Environmental Science and
Engineering,Shanghai Jiaotong University,Shanghai 200240,China;
2.State Key Laboratory of Pollution Control and Resource
Reuse,Tongji University,Shanghai 200092,China)

Abstract：The short-cut nitrification can be attained
efficiently and steadily in coke plant wastewater treatment by using
submerged membrane sequencing batch reactor (SMSBR),with an average
nitrosation rate (NO2-N/NOx-N) of 91.1%.The experimental results
show that long SRT has resulted in the inhibition of nitrate
bacteria caused by the metabolic products of microorganism.In the
initial stage of experiment,　the metabolic products are not
adequately accumulated due to short SRT and nitrification is carried
out in a complete way.And then denitrification occurs based on the
efficient and short-cut nitrification.When denitrification loading
is＜0.174 kg NOx-N/(kgSS·d) and HRT＞8.44 h,denitrification rate of　
81.34% can be achieved,with external carbon
COD∶N=2.1∶1.
Keywords:　SMSBR;coke plant
wastewater;short-cut nitrification and denitrification

　　短程硝化—反硝化(Shortcut nitrification and
denitrification)是指将硝化控制在形成亚硝酸盐阶段，然后进行亚硝酸盐的反硝化。该脱氮工艺可节省供氧量约25%；可节省反硝化所需碳源的40%，在C/N值一定的情况下可提高TN的去除率；可减少50%的污泥生成量，也减少了投碱量；缩短了反应时间，相应地减少了反应器容积。
　　短程硝化的标志是获得稳定高效的HNO2的积累，即亚硝酸化率(NO₂-N/NOX-N)＞50%。荷兰Delft技术大学开发的SHARON工艺，利用在较高温度(30～35
℃)下硝酸盐细菌的生长速率明显低于亚硝酸盐细菌的特点，在完全混合反应器中通过控制温度和停留时间，将硝化菌从反应器中洗脱，使反应器中亚硝化细菌占绝对优势，从而使氨氧化控制在亚硝酸盐阶段^［1］。
　　目前膜生物反应器(MBR)脱氮工艺形式多是建立在传统硝化—反硝化机理之上的两级或单级脱氮工艺，短程硝化反硝化现象在MBR工艺中体现得较少，Wouter
Ghyoot^［2］和W.J.Ng^［3］在各自的MBR研究中都发现有一定程度的NO₂-N积累(出水NO₂-N/NOX-N＞50%)的现象，并对此进行了解释，但不够理想。笔者在采用SMSBR处理焦化废水的研究中获得了高效稳定的短程硝化作用^［4］，现对其作用过程及形成原因作一探讨。