【作者】 王东阳；

【导师】 任南琪；

【作者基本信息】 哈尔滨工业大学 ， 环境工程， 2011， 博士

【摘要】 由于生物制氢技术具有清洁无污染和可再生性等优点，被普遍认定是符合低碳战略和可持续发展战略的一种新型生物技术。在生物制氢技术中，发酵法生物制氢因稳定性好、产氢能力高而具有更好的工业化前景。乙醇型发酵产氢是一种新发现的混合培养发酵法生物制氢方法。本文围绕着乙醇型发酵产氢过程的快速启动和生物强化进一步提高产氢效能开展研究，以期为生物制氢技术的工业化提供技术依据和理论支撑。采用糖蜜废水作为有机碳源，利用连续流完全混合搅拌槽式反应器（CSTR），探讨了乙醇型发酵和丁酸型发酵产氢过程的差异，证实了前者具有更优的产氢特性。通过探讨乙醇型发酵产氢过程的快速启动、控制方法及控制参数，以及系统的运行稳定性，表明以控制有机负荷（OLR）为主，以pH值监测和调节为辅助的手段能够较快地形成乙醇型发酵类型。实验结果表明，接种活性污泥量（以VSS计）为17.7g/L，温度为35℃，HRT为6h，当厌氧发酵产氢系统的pH降低到3.2时，产乙醇菌群受到的抑制程度是最小的；当发酵产氢系统的pH恢复到4.6时，产乙醇菌群的代谢活性恢复较快，通过调节进水COD浓度(启动初期4000mg/L下降到2000mg/L)，并以调节系统pH值为辅助手段，厌氧发酵制氢系统可在11d左右完成乙醇型发酵的快速启动。利用颗粒活性炭的吸附性能，对CSTR生物产氢反应器的活性污泥进行固定化，形成完全混合生物膜法制氢工艺。在连续流运行过程中，获得了不同的产酸发酵类型及产氢能力。丁酸型发酵和乙醇型发酵适宜的pH值范围分别为4.4~4.7和4.0~4.2，ORP范围分别为－200~－350mV和－330~－350mV。乙醇型发酵获得的最大产氢速率为3.9m~3/(m~3·d)，氢气含量56%，优于丁酸型发酵。冲击负荷实验表明，COD有机负荷从正常运行时的40kg/(m~3·d)降低到12kg/(m~3·d)，运行7d后，再提升到28kg/(m~3·d)的过程中，系统的pH值虽然下降至3.2，但是恢复正常的底物供给时，系统pH值很快恢复至4.5左右，氢气含量从17%上升到48%，产气量增加30%。这说明完全混合生物膜法制氢工艺具有良好的缓冲性能及运行稳定性。采用高效产氢菌种对CSTR产氢系统实施生物强化，确定了连续流发酵法产氢工艺的最佳生物强化控制参数和高效菌种的投加技术。研究表明，系统在一定控制条件下达到稳定运行状态，在有机负荷为12kgCOD/(m~3·d)、投加菌种量为5%的条件下，系统生物强化作用后的平均产气能力和平均产氢能力比生物强化处理前分别提高了12.9%和18%。而且，生物强化作用进一步提高了反应系统的运行稳定性。更多还原

【Abstract】 Biohydrogen production is a new technology which accords with the strategyof continuous development because of its prominent advantage of cleanness andhigh efficiency. Among the ways of biohydrogen production, biohydrogenproduction from fermentation is more prominent than biohydrogen production fromphotosynthesis because of its stability and ability of hydrogen production. Theethanol type of biohydrogen production from fermentation regarded as the optimalone for the biohydrogen production from fermentation process. Therefore, it wasinvestigated the rapid start up of ethanol type of fermentatitive hydrogen productionand effects of bioaugment on hydrogen production, in order to provide fermentativehydrogen production for industrialization.The difference of hydrogen production in ethanol type and butyrate typefermentation with continuous stirred tank reactor (CSTR) using molasseswastewater as organic substrate was investigated. It was also explored how torealize the quick start up ethanol type fermentation. The CSTR reator was opratedwith VSS of17.7g/L, temperature of35°C, HRT of6h. The results showd thatethanol producing bacterial was inhibited least when pH was3.2in the reactor andthe activity of ethanol producing bacterial restored faster compared with otherbacterial. Therefore, it was concluded that the anaerobic fermentative hydrogenproduction system could form ethanol type fermentation in11d with influent CODdecreased from4000mg/L to2000mg/L and the assistance of pH.Utilizing the adsorption performance of granular activated carbon, aerobiccultivated sewage sludge was self-immobilized as biological carriers. A completelymixed bio-film process for hydrogen production was developed by the combinationof biological carriers and continuous stirred tank reactor. In the long timecontinuous operation, hydrogen producing ability and ecological factors underdifferent organic wastewater acidogenic fermentation types were obtained. Butyricacid fermentation and ethanol fermentation were feasible in the pH ranges4.4~4.7,4.0~4.2, respectively; while ORP ranges were-200~-350mV,-330~-350mV,respectively. The reactor with ethanol fermentation achieved a maximum hydrogenyield rate of3.9m~3/(m~3·d) while hydrogen content was56%, superior to other fermentation types. To simulate load impact in actual operation, COD organicloading rate was reduced to12kg/(m~3·d) from40kg/(m~3·d) and promoted to28kg/(m~3·d) after7days. Although the pH value once drops to3.2during fiercefluctuations, the pH value ascended to4.5and gross gas production raised30%withthe hydrogen content promoted to48%from17%when the normal substrate supplywas restored. It is indicated that the completely mixed bio-film hydrogen productionreactor has good buffer performance and operational stability.Optimal biological enhanced control parameters and efficient strain dosingtechnology for continuous flow fermentation hydrogen production process aredetermined by implementation of bio-enhanced hydrogen for CSTR system by usingefficient hydrogen strains. The results demonstrated that, when the system wasstabled at OLR of12kg COD/m~3·d, and the inoculation quantity of R3was5%, theaverage biogas production capacity and the average hydrogen production capacitywere improved12.9%and18%, respectively. Moreover, the composition of thefermentation products and operational stability were improved.更多还原