采用序批式反应器短程生物脱氮工艺处理高氨氮制药废水

Nitrogen removal from pharmaceutical wastewater via nitrite using sequencing batch reactor

根据制药废水高氨氮、高pH值、高碱度的特点,采用序批式反应器(SBR)对该废水短程生物脱氮的可行性和影响因素进行了研究。在常温(23±1)℃的条件下,实现了低碳氮比制药废水的短程硝化与反硝化,脱氮效率达99％以上。结果表明,在高游离氨条件下,硝酸菌比亚硝化菌对游离氨更为敏感,反应体系中亚硝酸盐的平均积累速率远大于硝酸盐的平均积累速率。在处理该制药废水的短程硝化与反硝化过程中,pH值的变化表现出一定的规律性,其变化反映了硝化和反硝化进行的程度。可以利用pH值变化的特征点来准确判断硝化和反硝化过程的结束,进而实现对该过程的在线模糊控制。

Laboratory-scale experiments were conducted applying sequencing batch reactor (SBR) activated sludge processto a wastewater stream from a pharmaceutical factory. Nitrogen removal can be achieved via partial nitrification and denitrifica-tion and the efficiency was above 99% at (23±1)℃. The experimental results indicate that the nitrite oxidizers are more sensi-tive to free ammonia than ammonia oxidizers in the wastewater. The average accumulation rate of nitrite is much higher than thatof nitrate. During the nitrogen removal via nitrite pathway,the end of nitrification and denitrification can be exactly decided bymonitoring the variation of pH. Consequently, on-line control for nitrogen removal from the pharmaceutical wastewater can beachieved and the cost of operation can be reduced.