无机碳源对零价铁介导的自养脱氮序批式反应器处理高氨氮废水的影响

无机碳源作为自养微生物的能量来源,是影响自养脱氮细菌富集的重要因素。文章通过添加不同量的KHCO3作为ZVI介导的自养脱氮体系中无机碳源,研究反应体系的脱氮效果影响趋势以及适宜的无机碳源添加量。结果如下:1)KHCO3作为无机碳源可以显著提高NH^+4-N去除率,KHCO3添加量越多,其NH^+4-N去除率越高。KHCO3添加量分别为2 g,1 g,0.5 g的SBR反应器R2,R1,R0.5的NH^+4-N去除率分别为98.39%,65.18%,44.56%,相较不添加KHCO3的R0分别提高86.5%,53.29%,32.67%。ZVI的添加会降低KHCO3对NH^+4-N氧化的促进作用。2)KHCO3可明显提高TIN去除效果,促进总氮脱除的高低顺序是R1>R0.5>R2,SBR反应器R2,R1,R0.5的平均TIN去除率分别为19.01%,32.04%,27.62%,相较于空白组R0分别提高了10.60%,23.63%,19.21%。3)KHCO3可中和硝化反应产生的H^+,对反应体系具有缓冲作用,可使微生物处于较适宜的酸碱环境中,更有利于反应器的稳定运行。4)适量的无机碳源KHCO3可以促进氨氧化细菌和厌氧氨氧化细菌的活性。该研究探讨了无机碳源在零价铁脱氮体系中的影响趋势,为铁型脱氮技术提供了理论支撑。

Effects of Inorganic Carbon on the Treatment of High Ammonia Nitrogen Wastewater by Zero Valent Iron-mediated Autotrophic Nitrogen Removal in Sequencing Batch Reactor

As the energy source of autotrophic microorganisms,the inorganic carbon source is an important factor affecting the enrichment of autotrophic denitrifying bacteria.In this paper,different amounts of KHCO3 were added as inorganic carbon source in the ZVI-mediated autotrophic nitrogen removal system,and the trend of its influence on nitrogen removal as well as the appropriate additive amount were studied.The results are as follows:1)As an inorganic carbon,KHCO3 could significantly improve the removal rate of NH^+4-N.The more KHCO3 was added,the higher NH^+4-N removal rate would be.When the KHCO3 addition amount were 2,1 and 0.5 g,the removal rates of NH^+4-N in R2,R1 and R0.5 of SBRs were 98.39%,65.18%and 44.56%,respectively,which were 86.5%,53.29%and 32.67%higher than that in R0 without the addition of KHCO3.The addition of ZVI would reduce the catalytic effect of KHCO3 on NH^+4-N oxidation.2)KHCO3 can significantly improve the TIN removal performance,and the order of promoting nitrogen removal was R1>R0.5>R2.The average TIN removal rates of R2,R1 and R0.5 were 19.01%,32.04%and 27.62%respectively,which were 10.60%,23.63%and 19.21%higher than that of R0.3)KHCO3 could neutralize the H^+generated by nitrification with a buffering effect on the reaction system,so that microorganisms could be in a more suitable acid-base environment,which is more conducive to the stable operation of the reactor.4)An appropriate amount of inorganic carbon KHCO3 could promote the activities of ammonia-oxidizing bacteria and anaerobic ammonia-oxidizing bacteria.This study discussed the influence trend of inorganic carbon source on ZVI autotrophic nitrogen removal system,which may provide theoretical support for iron involvled autotrophic nitrogen removal technology.