生物强化方式对生物转盘处理养殖废水效果及生物多样性的影响

Comparison of Swine Wastewater Treatment Performance and Microbial Diversity of Rotating Biological Contractor with Different Bioaugmentation Methods

畜禽养殖废水污染物浓度高、生物毒性大,导致传统生物处理工艺难以满足达标排放要求.为探究高效的畜禽养殖废水处理工艺,采用生物转盘作为主体工艺,利用异养硝化-好氧反硝化菌(简称“HN-AD菌”)为生物强化菌剂,对比了强化污泥挂膜和菌剂挂膜两种不同生物强化方式下该工艺在启动时间、碳耗、能耗、真实废水处理效果及微生物多样性方面的差异,以确定最佳生物强化方式.结果表明:①模拟废水试验中,菌剂挂膜反应器启动时间(19 d)明显短于强化污泥挂膜(33 d),参数优化后发现,在相同处理效果下,前者碳耗、能耗较后者分别低48.22%、33.33%.②真实废水处理试验中,菌剂挂膜反应器的COD Cr、NH4^+-N、TN平均去除率较后者分别高7.11%、26.97%、29.14%.③在微生物多样性方面,菌剂挂膜体系中Comamonas(丛毛单胞菌属)相对丰度是强化污泥挂膜体系的10倍左右,推测Comamonas可能是在异养硝化好氧反硝化过程中发挥关键作用的菌属.④SEM观察发现菌剂挂膜生物转盘盘片上的生物膜更薄,但HN-AD优势菌富集程度更高.研究显示,菌剂挂膜反应器对模拟废水、真实废水的处理效果均优于强化污泥挂膜反应器,且效果更稳定.

The high concentration and biological toxicity of pollutants in livestock and poultry farming wastewater makes it difficult for traditional biological treatment processes to meet the discharge requirements.In order to explore high efficient process for swine wastewater treatment,a rotating biological contractor was used as the main process,and heterotrophic nitrification-aerobic denitrification bacteria(hereinafter refer to HN-AD bacteria)as the bioaugmentation agent.The differences of start-up time,carbon consumption,energy consumption,raw swine wastewater treatment effect and microbial diversity between two bioaugmentation methods of enhanced sludge inoculation film formation and microbial agent inoculation biofilm formation were compared to determine the best bioaugmentation method.The results demonstrated that,in the simulated wastewater experiments,the start-up time of membrane reactor required for microbial agent inoculation biofilm formation(19 d)was significantly shorter than that for sludge inoculation biofilm formation(33 d)after parameter optimization.Under the same treatment effect,the carbon consumption and energy consumption of the former were 48.22%and 33.33%less than the latter,respectively;In raw swine wastewater treatment,the average removal efficiency of COD Cr,NH4^+-N and TN by microbial agent inoculation biofilm formation were 7.11%,26.97%and 29.14%higher than those of the latter,respectively;In terms of microbial diversity,the abundance of Comamonas of the microbial agent inoculation biofilm formation system was about 10 times higher than that in the enhanced sludge inoculation film formation system,suggesting that Comamonas might play a key role in the process of heterotrophic nitrification-aerobic denitrification;SEM images showed that the biofilm on the bio-disk of microbial agent inoculation biofilm formation system was thinner,but HN-AD predominant bacteria were more abundant than that of enhanced sludge inoculation film formation system.The results show that the treatment effect of the microbial agent inoculation biofilm formation on simulated wastewater and real wastewater is better than that of the enhanced sludge inoculation film formation,and the resistance to parameter changes is better.