Enhanced Biohydrogen Production from Sewage Sludge with Alkaline Pretreatment
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- 作者：Mulin Cai ; Junxin Liu ; and Yuansong Wei
- 刊名：Environmental Science & Technology
- 出版年：2004
- 出版时间：June 1, 2004
- 年：2004
- 卷：38
- 期：11
- 页码：3195 - 3202
- 全文大小：460K
- 年卷期：v.38,no.11(June 1, 2004)
- ISSN：1520-5851
文摘
Batch tests were carried out to analyze influences of thealkaline pretreatment and initial pH value on biohydrogenproduction from sewage sludge. Experimental results of theimpact of different initial pH on biohydrogen productionshowed that both the maximal hydrogen yield occurred andthat no methane was detected in the tests of at theinitial pH of 11.0. The final pH decreased at the initial pHof 7.0-12.5 but increased at the initial pH of 3.0-6.0, probablydue to the combination of solubilized protein from sludgeand the formation of volatile fatty acids (VFAs) and ammoniaduring biohydrogen fermentation. The performance ofbiohydrogen production using the raw sludge and thealkaline pretreated sludge was then compared in batchfermentation tests at the initial pH of 11.0. The hydrogen yieldwas increased from 9.1 mL of H2/g of dry solids (DS) ofthe raw sludge to 16.6 mL of H2/g of DS of the alkalinepretreated sludge. No methane and less carbon dioxide (0.8%of control) were present in the biohydrogen productionfrom the alkaline pretreated sludge. These results clearlyshowed that biohydrogen production could be enhancedand maintained stable by the combination of the high initialpH and alkaline pretreatment. The mechanism ofbiohydrogen production from sewage sludge at high initialpH was therefore investigated because the results ofthis study were different from previous studies of biohydrogenproduction. Results showed that protein was the majorsubstrate for biohydrogen production from sewage sludgeand that Eubacterium multiforme and Paenibacilluspolymyxa were the dominant bacteria in biohydrogenproduction from alkaline pretreated sludge at an initial pHof 11.0. The combination of alkaline pretreatment andhigh initial pH could not only maintain a suitable pH rangefor the growth of dominant hydrogen-producing anaerobesbut also inhibit the growth of hydrogen-consuminganaerobes. In addition, the changes in pH value, oxidation-reduction potential, VFAs and soluble COD during hydrogenfermentation were also discussed.