Abstract:
Thermophilic anaerobic digestion (AD) of animal manure offers various environmental benefits but the process requires a microbial community acclimatized to high ammonia. In current study, a lab-scale continuous stirred tank reactor (CSTR) fed with chicken manure was operated under thermophilic condition for 450 days in total. Results showed that the volumetric methane production decreased from 445 to 328 and sharply declined to 153 mL L-1·d-1 with feeding total solid (TS) step increased from 5% to 7.5% and 10%, respectively. While, after a long-term stop feeding for 80 days, highly disturbed reactor was able to recover methane generation to 739 mL L-1·d-1 at feeding TS of 10%. Isotope analysis indicted acetate converted to methane through the syntrophic acetate oxidation and hydrogenotrophic methanogenesis (SAO-HM) pathway increased from 33% to 63% as the concentration of ammonium increased from 2493 to 6258 mg L-1. Significant different in the genome expression of the SAO bacterial from 0.09% to 1.23%, combining with main hydrogenotrophic partners (Methanoculleus spp. and Methanothermobacter spp.) contented of 2.1% and 99.9% during inhibitory and recovery stages, respectively. The highly expressed KEGG pathway in level 3 (enzyme genes) for the Recovery sludge combining with the extraordinary high abundance of genera Halocella sp. suggested that Halocella sp. might be a highly efficient hydrolytic and acidogenic microorganism and enhance the process of SAO during carbon metabolic flow to methane. This report will be a basis for further study of AD studies on high nitrogen content of poultry manure.
摘要:
动物粪便的嗜热厌氧消化(AD)提供了各种环境效益,但该过程需要适应高氨的微生物群落。在目前的研究中,实验室规模的连续搅拌釜反应器(CSTR)在嗜热条件下总共运行450天。结果表明,随着总固体(TS)步数从5%增加到7.5%和10%,体积甲烷产量从445下降到328,急剧下降到153mL·L-1·d-1。分别。同时,在长期停止喂食80天后,在进料TS为10%的情况下,高度干扰的反应器能够恢复甲烷生成至739mL·L-1·d-1。同位素分析表明,随着铵的浓度从2493增加到6258mg·L-1,乙酸盐通过营养乙酸盐氧化和氢营养甲烷生成(SAO-HM)途径转化为甲烷从33%增加到63%。SAO细菌的基因组表达差异显著,从0.09%到1.23%,与主要氢营养型伴侣(甲烷菌属。和甲烷热杆菌。)在抑制和恢复阶段的含量为2.1%和99.9%,分别。回收污泥在3级(酶基因)中高度表达的KEGG途径与非常丰富的Halocellasp。建议Halocellasp.可能是一种高效的水解和产酸微生物,并在碳代谢流向甲烷的过程中增强了SAO的过程。该报告将为进一步研究高氮含量家禽粪便的AD研究奠定基础。