Kinetic Difference between Acetate and Propionate Pregrown Reactors through Batch Methanogenesis Experiments

Two pregrown inocula, pre-acclimated to acetate and propionate respectively and mainly composed of coccus, diplococcus-shaped Methanosarcina -like cells and a few filamentous Methanothrix -like cells, were used separately in batch experiments to investigate the effects of varied initial acetate or propionate concentrations on methanogenesis of mixed acetate and propionate substrate under controlled neutral pH and 35±1 ℃ conditions. The results indicated that acetate pregrown systems exhibited excellent and stable degradation potentials for acetate, with maximum specific substrate degradation rate ( q max ) ranging from 1100 to 1900 mg/g － VSS/d when initial acetate and propionate less than 3300 mg/ l and 750 mg/ l , respectively. Under the same conditions, no distinctive difference in methane production was found for both pregrown systems, with the highest methane production rates of 107 － 117 m l / l － reactor/d and methane yields ranging from 0.31 to 0.36 l /g － COD removed. The average acetate and propionate degradation rates obtained were 66.7 － 307.2 and 3.8 － 86.0 mg/ l － reactor/d and 26.7 － 265.7 and 5.8 － 92.0 mg/ l － reactor/d for acetate pregrown and propionate pregrown systems, respectively, which were found to have some negative correlations with initial propionate/ acetate(P/A) ratio (0 － 3.0) and initial VFA load (165.7 － 436.1 mgCOD/ l － reactor/d), respectively. It is still a challenge to maintain and control the effectiveness of propionate degradation in pregrown systems.

[1]  D. Cheong,et al.  Effect of feeding strategy on the stability of anaerobic sequencing batch reactor responses to organic loading conditions. , 2008, Bioresource technology.

[2]  C. Gallert,et al.  Propionic acid accumulation and degradation during restart of a full-scale anaerobic biowaste digester. , 2008, Bioresource technology.

[3]  B. Ahring,et al.  Regulation and optimization of the biogas process: Propionate as a key parameter , 2007 .

[4]  O. Ince,et al.  Determination of optimum operating conditions of an acidification reactor treating a chemical synthesis-based pharmaceutical wastewater , 2006 .

[5]  Grietje Zeeman,et al.  The effects of operational and environmental variations on anaerobic wastewater treatment systems: a review. , 2006, Bioresource technology.

[6]  K. Wuhrmann,et al.  Product inhibition in sludge digestion , 1977, Microbial Ecology.

[7]  S. Sayadi,et al.  Evaluating process imbalance of anaerobic digestion of olive mill wastewaters , 2005 .

[8]  Chika Tada,et al.  Influence of bed materials on methanogenic characteristics and immobilized microbes in anaerobic digester , 2004 .

[9]  H. Harada,et al.  Microbial characteristics of methanogenic sludge consortia developed in thermophilic U ASB reactors , 1993, Applied Microbiology and Biotechnology.

[10]  Jie Ding,et al.  [Organic acids conversion in methanogenic-phase reactor of the two-phase anaerobic process]. , 2003, Huan jing ke xue= Huanjing kexue.

[11]  J. Horiuchi,et al.  Selective production of organic acids in anaerobic acid reactor by pH control. , 2002, Bioresource technology.

[12]  Heiko Feitkenhauer,et al.  On-line titration of volatile fatty acids for the process control of anaerobic digestion plants. , 2002, Water research.

[13]  B. Ahring,et al.  A comprehensive study into the molecular methodology and molecular biology of methanogenic Archaea. , 2001, FEMS microbiology reviews.

[14]  B. Ahring,et al.  Effect of temperature increase from 55 to 65 degrees C on performance and microbial population dynamics of an anaerobic reactor treating cattle manure. , 2001, Water research.

[15]  Hans-Joachim Jördening,et al.  Comparison of different models of substrate and product inhibition in anaerobic digestion , 1999 .

[16]  Qunhui Wang,et al.  Degradation of volatile fatty acids in highly efficient anaerobic digestion , 1999 .

[17]  V. Vavilin,et al.  Modeling of volatile fatty acids degradation kinetics and evaluation of microorganism activity , 1996 .

[18]  J. Lema,et al.  Degradation of volatile fatty acids by differently enriched methanogenic cultures: Kinetics and inhibition , 1995 .

[19]  R. L. Earle,et al.  Degradation of acetic and propionic acids in the methane fermentation , 1991 .

[20]  Mustafa Öztürk.  Conversion of acetate, propionate and butyrate to methane under thermophilic conditions in batch reactors , 1991 .

[21]  S. Pavlostathis,et al.  Kinetics of Anaerobic Treatment , 1991 .

[22]  D. T. Hill,et al.  Using volatile fatty acid relationships to predict anaerobic digester failure. , 1987 .

[23]  Chiu-Yue Lin,et al.  Methanogenic digestion using mixed substrate of acetic, propionic and butyric acids , 1986 .

[24]  E. L. Iannotti,et al.  Anaerobic digestion of swine manure at various influent solids concentrations , 1984 .

[25]  R. Mah,et al.  Growth and Methanogenesis by Methanosarcina Strain 227 on Acetate and Methanol , 1978, Applied and Environmental Microbiology.

[26]  L. Berg,et al.  Anaerobic Digestion of Pear Waste: Laboratory Equipment Design and Preliminary Results , 1971 .

[27]  R. Mah,et al.  Kinetics of acetate metabolism during sludge digestion. , 1966, Applied microbiology.