SBBR工艺中亚硝酸型同步硝化反硝化的过程控制

PROCESS CONTROL OF SIMULTANEOUS NITRIFICATION AND DENITRIFICATION VIA NITRITE IN SEQUENCING BATCH BIOFILM REACTOR

采用序批式生物膜反应器(SBBR),在生物膜培养驯化初期实现了亚硝酸盐硝化,通过调节曝气量控制系统内的溶解氧浓度,实现了SBBR工艺中的亚硝酸型同步硝化反硝化生物脱氮,出水中亚硝酸盐累积率(NO2--N/NOx--N)达到90%左右,TN低于8mg·L-1,去除率为71.4%～85.6%。为了实现SBBR工艺中亚硝酸型同步硝化反硝化的过程控制,考察了亚硝酸型同步硝化反硝化生物脱氮过程中DO、pH和ORP的变化规律。试验结果表明,DO、pH和ORP的变化规律与反应器内COD的降解和"三氮"的转化有良好的相关性,并在不同温度条件下的亚硝酸型同步硝化反硝化硝化过程中具有良好的重现性,可以依据DO、pH和ORP在变化曲线上的特征点作为SBBR法亚硝酸型同步硝化反硝化的过程控制参数。

Nitrite can be accumulated in the initial cultivation and attenuation stage ofbiofilm in sequencing batch biofilm reactor （SBBR）. Nitrogen removal from wastewater by simultaneous nitrification and denitrification via nitrite was achieved by controlling dissolved oxygen （DO） concentration in SBBR. The nitrate accumulation rate removal rate （NO2^--N / NOx-N）was 90% and TN was always less than 8mg/L when aeration was ended. The TN removal can reach between 71.4% and 85.6%. In order to achieve the process control of simultaneous nitrification and denitrification via nitrite in SBBR, the variation patterns of DO, pH and ORP during simultaneous nitrification and denitrification via nitrite were studied. The results showed that the variation of DO,pH and ORP were well related to organic degradation, nitrification and denitrification of SBBR. So that DO, pH and ORP can be used as process control parameters for the simultaneous nitrification and denitrification via nitrite in SBBR based on the varied curve of DO, pH and ORP.