Utilization of a palladium-metal oxide semiconductor (Pd-MOS) sensor for on-line monitoring of dissolved hydrogen in anaerobic digestion.

The use of a hydrogen-sensitive palladium-metal oxide semiconductor (Pd-MOS) sensor in combination with a membrane for liquid-to-gas transfer for the detection of dissolved hydrogen was investigated. The system was evaluated with known concentrations of dissolved hydrogen in water. The lowest concentration detected with this set-up was 160 nM. The method was applied to monitoring of a laboratory-scale anaerobic digestion process employing mixed sludge containing mainly food/industrial waste. Pulse loads of glucose were added to the system at different levels of microbial activity, and the microbial status of the culture was reflected in the dissolved hydrogen response. Simultaneous headspace hydrogen measurements were performed, and at the lower levels of dissolved hydrogen no corresponding headspace hydrogen could be detected. When glucose was added to a resting culture the dissolved hydrogen response was rapid and the first response could be detected 9 min after addition of glucose, whereas headspace hydrogen concentrations increased only after 80 to 110 min. This indicates limitations in the liquid-to-gas hydrogen transfer and illustrates the importance of hydrogen monitoring in the liquid. The sensor system developed is flexible, the membrane is easily replaceable, and the probe for liquid-to-gas hydrogen transfer can be adjusted easily to large-scale applications.

[1]  R Cord-Ruwisch,et al.  An in situ dissolved‐hydrogen probe for monitoring anaerobic digesters under overload conditions , 1995, Biotechnology and bioengineering.

[2]  D. B. Nedwell,et al.  An investigation into the suitability of biogas hydrogen concentration as a performance monitor for anaerobic sewage sludge digesters , 1991 .

[3]  Heinzle,et al.  Dynamic determination of anaerobic acetate kinetics using membrane mass spectrometry , 1998, Biotechnology and bioengineering.

[4]  Frédéric Ehlinger,et al.  On-line automatic control system for monitoring an anaerobic fluidized-bed reactor: response to organic overload , 1994 .

[5]  S. R. Harper,et al.  Recent developments in hydrogen management during anaerobic biological wastewater treatment. , 1986, Biotechnology and bioengineering.

[6]  R. Cord-Ruwisch,et al.  Dissolved hydrogen concentration as an on-line control parameter for the automated operation and optimization of anaerobic digesters. , 1997, Biotechnology and bioengineering.

[7]  F. E. Mosey,et al.  Patterns of Hydrogen in Biogas from the Anaerobic Digestion of Milk-Sugars , 1989 .

[8]  Peter F. Stanbury,et al.  Development of a dissolved hydrogen sensor and its application to evaluation of hydrogen mass transfer , 1993 .

[9]  R. Conrad,et al.  Measurement of dissolved H2 concentrations in methanogenic environments with a gas diffusion probe , 1993 .

[10]  E. Arnold,et al.  Standard methods for the examination of water and wastewater. 16th ed. , 1985 .

[11]  Serge R. Guiot,et al.  Impact of liquid-to-gas hydrogen mass transfer on substrate conversion efficiency of an upflow anaerobic sludge bed and filter reactor , 1995 .

[12]  T. J. Phelps,et al.  Gas Metabolism Evidence in Support of the Juxtaposition of Hydrogen-Producing and Methanogenic Bacteria in Sewage Sludge and Lake Sediments , 1985, Applied and environmental microbiology.

[13]  J. A. Robinson,et al.  In situ rumen hydrogen concentrations in steers fed eight times daily, measured using a mercury reduction detector , 1988 .

[14]  M Perrier,et al.  Liquid-to-Gas Mass Transfer in Anaerobic Processes: Inevitable Transfer Limitations of Methane and Hydrogen in the Biomethanation Process , 1990, Applied and environmental microbiology.

[15]  André Pauss,et al.  Hydrogen monitoring in anaerobic sludge bed reactors at various hydraulic regimes and loading rates , 1993 .

[16]  Ingemar Lundström,et al.  A hydrogen sensitive Pd-MOS structure working over a wide pressure range , 1984 .

[17]  Serge R. Guiot,et al.  Continuous measurement of dissolved H2 in an anaerobic reactor using a new hydrogen/air fuel cell detector , 1990, Biotechnology and bioengineering.

[18]  E. G. Hörnsten On culturing Escherichia coli on a mineral salts medium during anaerobic conditions , 1995 .

[19]  W. Seiler,et al.  Production and Consumption of Hydrogen in a Eutrophic Lake , 1983, Applied and environmental microbiology.

[20]  Ingemar Lundström,et al.  Hydrogen sensitive mos-structures: Part 1: Principles and applications , 1981 .

[21]  D. Lloyd,et al.  Continuous measurement of dissolved gases in biochemical systems with the quadrupole mass spectrometer. , 1985, Methods of biochemical analysis.

[22]  J. A. Robinson,et al.  Kinetics of Hydrogen Consumption by Rumen Fluid, Anaerobic Digestor Sludge, and Sediment , 1982, Applied and environmental microbiology.

[23]  Membrane inlet mass spectrometry — measurement of dissolved gases in fermentation liquids , 1983 .

[24]  D. L. Hawkes,et al.  Hydrogen production in a high rate fluidised bed anaerobic digester , 1997 .

[25]  David C. Stuckey,et al.  Stability enhancement of anaerobic digestion through membrane gas extraction under organic shock loads , 1998 .

[26]  Shiro Nagai,et al.  Measurement of dissolved hydrogen in an anaerobic digestion process by a membrane-covered electrode , 1991 .

[27]  B. Mathisen,et al.  The use of palladium metal oxide semiconductor structures in quantitative studies of H2 and H2S in processes related to biogas production , 1991 .