Response of morphology and microbial community structure of granules to influent COD/SO42- ratios in an upflow anaerobic sludge blanket (UASB) reactor treating starch wastewater
Response of morphology and microbial community structure of granules to influent COD/SO42- ratios in an upflow anaerobic sludge blanket (UASB) reactor treating starch wastewater
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DOI：
10.1016/j.biortech.2018.02.055
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发表时间：
2018-05-01
影响因子：
11.4
通讯作者：
Li, Yu-You
中科院分区：
文献类型：
--
作者：
Lu, Xueqin;Ni, Jialing;Li, Yu-You
颗粒污泥的生化特性对UASB的性能有着至关重要的影响。本研究对不同COD/SO42-比培养的颗粒污泥进行了表征，以阐明硫化作用对淀粉废水(1000 mg-COD L-1)生物降解动力学和工艺稳定性的影响。适当的硫酸盐添加丰富了颗粒微生态系统，促进了胞外物质的分泌，促进了细胞的凝聚和污泥的聚集。随着COD/SSO(4)(2-)比从10降低到2，大于2.8 mm的颗粒所占比例从10.0%增加到58.8-69.4%。被亲水性生物聚合物淹没的纤维对沼气泡和水分子具有很高的亲和力，加剧了颗粒的漂浮和冲刷。16 S rRNA基因分析表明，降低COD/SO(4)(2-)比使合养细菌向脱硫弧菌转化，与甲烷杆菌协同作用，抑制甲烷杆菌，从而改变淀粉的生物转化途径。合养细菌的减少导致丙酸的积累和轻微的过程紊乱。
Biochemical properties of granules are of vital importance to UASB performance. This study characterized the granules cultivated at different COD/SO42- ratios to elucidate the influence of sulfidogenesis on starch wastewater (1000 mg-COD L-1) biodegradation kinetics and process stability. Suitable sulfate addition enriched granular microecosystems and stimulated the secretion of extracellular substances, facilitating cells cohersion and sludge aggregation. The percentage of granules larger than 2.8mm increased from< 10.0% to 58.8-69.4% with decreasing COD/SSO(4)(2-)ratio from 10 to 2. Starch-fed granules tended to grow flagella-like filaments on the surface. The filaments overwhelmed by hydrophilic biopolymers had high affinity for biogas-bubbles and water-molecules aggravating granule floatation and washout. 16 s rRNA gene analysis revealed that decreasing COD/SO(4)(2-)ratio shifted Syntrophobacterales to Desulfovibrio, which co-worked with Methanosaeta while suppressing Methanobacterium thereby altering starch bioconversion routes. Decrease in Syntrophobacterales caused propionate accumulation and slight process upset.