体系含固率对土霉素菌渣厌氧消化的影响

Effect of system solids content on anaerobic digestion of oxytetracycline residues

针对抗生素菌渣危害性大、处理处置困难等的问题,采用厌氧消化技术可在降低污染物的同时产生清洁能源,是实现抗生素菌渣减量化、资源化和无害化处理的重要途径。含固率(TS)是厌氧消化的重要影响因素之一,通过改变体系的含固率,研究其对土霉素菌渣厌氧消化系统的影响。结果表明,系统内氨氮、挥发性脂肪酸(VFAs)均随TS的增加而增加,当氨氮浓度大于2000 mg·L^(-1)、VFAs大于4000 mg·L^(-1)时,会对系统产生明显的抑制作用。系统稳定性能、产气效率以及有机物去除效率均随TS的增加而降低。TS为4%的反应组在各方面均优于其他组,且其中残留的土霉素去除效率最高,可基本实现菌渣的无害化处理。对体系内优势微生物群落进行分析发现,产甲烷菌的优势菌群以Methanosarcinaceae和Methanosaetaceae为主,可知,土霉素菌渣的厌氧发酵以乙酸型发酵为主。本研究结果可为厌氧消化技术在抗生素菌渣处理处置中的应用提供理论参考。

In response to the problems of hazardous antibiotic residues and difficulties in treatment and disposal,the use of anaerobic digestion technology can reduce pollutants while generating clean energy,which is an important way to achieve the reduction,resourcefulness and harmless treatment of antibiotic residues.Solids content(TS)is one of the important influencing factors of anaerobic digestion,and its effect on the anaerobic digestion system of oxytetracycline residue was investigated by varying the solids content of the system.The results showed that the content of ammonia nitrogen and volatile fatty acids(VFAs)in the system increased with the increase of TS,and when the ammonia nitrogen was more than 2,000 mg·L^(-1)and VFAs was more than 4,000 mg·L^(-1),it would have a significant inhibitory effect on the system.System stability performance,gas production efficiency and organic removal efficiency all decrease with increasing TS.The reaction with TS of 4%outperformed the other groups in all aspects,and the highest efficiency of residual hygromycin removal was achieved,which could basically realize the harmless treatment of bacterial residue.Analysis of the dominant microbial community within its system revealed that the dominant methanogenic bacteria were dominated by Methanosarcinaceae and Methanosaetaceae,according to this analysis,the anaerobic digestion of oxytetracycline residue may be mainly acetic acid fermentation.The results of this study can provide a theoretical reference for the application of anaerobic digestion technology in the treatment and disposal of antibiotic residues.