接种污泥对产氢颗粒污泥形成的影响

采用两个平行的颗粒污泥膨胀床反应器(EGSB),控制温度为(35±0.5)℃,逐步提高进水容积负荷,分别研究接种污泥对产氢速率、颗粒粒径分布变化、液相末端产物和启动末期系统参数的影响.结果表明,采用缺氧污泥混合厌氧污泥进行接种的反应器比直接采用产甲烷颗粒污泥粉碎后接种的反应器更易形成颗粒污泥.在启动末期,前者的平均颗粒粒径为后者的1.25倍,产氢速率是后者的1.23倍.两个反应器都形成了乙醇型发酵,说明发酵类型的形成不受接种污泥影响.启动末期系统的pH值分别为3.9～4.3和4.0～4.4,混合污泥接种反应器的挥发性悬浮固体质量浓度为27.2g/L,厌氧污泥接种反应器的挥发性悬浮固体质量浓度为24.1g/L.相比厌氧污泥接种的反应器,混合污泥接种能更快速培养颗粒污泥,并且反应系统产氢速率高,耐酸性更好,生物持有量大,有利于生物制氢系统高效产氢和稳定运行.

Influence of seed sludge on granulation of hydrogen-production sludge

Two parallel lab-scale expanded granular sludge bed (EGSB) reactors were employed to evaluate the granulation of hydrogen-production sludge. One reactor was inoculated by a mixture of anoxic sludge and anaerobic sludge,the other by anaerobic sludge. By keeping temperature at (35 ±0. 5) ℃,hydrogen production rate (HPR),distribution of granular diameter,liquid end products and other parameters by the end of start-up stage were examined with the organic loading rate (OLR) increased. It was found that there was an easier granulation in the mixed sludge inoculated reactor. The medial diameter of granules and the HPR in the mixed reactor were 1. 25 times and 1. 23 times of those in the anaerobic one by the end. Both reactors formed ethanol-type fermantation,which suggested that fermentation type was not influenced by seed sludge. By the end of start-up stage,pH was 3. 9-4. 3 in the mixed sludge inoculated reactor and 4. 0-4. 4 in the other reactor. The mixed sludge inoculated reactor also maintained a higher volatile suspended solids (VSS) concentration of 27. 2 g/L than that of 24. 1 g/L for the other reactor. It is indicated that better granulation contributes to the high HPR and stable-running of the hydrogen production reactor. Moreover,mixture of anoxic sludge and anaerobic sludge is a better choice for inoculation.