Evaluating the influences of mixing strategies on the Biochemical Methane Potential test.
Mixing plays an important role in the Biochemical Methane Potential (BMP) test, but only limited efforts have been put into it. In this study, various mixing strategies were applied to evaluate the influences on the BMP test, i.e., no mixing, shaking in water bath, shake manually once per day (SKM), automated unidirectional and bidirectional mixing. The results show that the effects of mixing are prominent for the most viscous substrate investigated, as both the highest methane production and highest maximal daily methane production were obtained at the highest mixing intensity. However, the organic removal efficiencies were not affected, which might offer evidence that mixing helps the release of gases trapped in digester liquid. Moreover, mixing is required for improved methane production when the digester content is viscous, conversely, mixing is unnecessary or SKM might be sufficient for the BMP test if the digester content is quite dilute or the substrate is easily degraded.
Division of Biotechnology, Lund University, Naturvetarvägen 16, SE-222 41, Lund, Sweden. Electronic address: bing.wang@biotek.lu.se.
Bing
B
Wang
Department of Thematic Studies-Environmental Change, Linköping University, SE-581 83, Linköping, Sweden.
Annika
A
Björn
Bioprocess Control Sweden AB, Scheelevägen 22, SE-223 63, Lund, Sweden.
Sten
S
Strömberg
Division of Biotechnology, Lund University, Naturvetarvägen 16, SE-222 41, Lund, Sweden.
Ivo Achu
IA
Nges
Bioprocess Control Sweden AB, Scheelevägen 22, SE-223 63, Lund, Sweden.
Mihaela
M
Nistor
Division of Biotechnology, Lund University, Naturvetarvägen 16, SE-222 41, Lund, Sweden; Bioprocess Control Sweden AB, Scheelevägen 22, SE-223 63, Lund, Sweden.
Jing
J
Liu
D000693:Anaerobiosis; D019149:Bioreactors; D005740:Gases; D008697:Methane / Q000096:biosynthesis*
D005740:Gases; D008697:Methane
Anaerobic digestion; Biochemical methane potential; Degradation kinetics; Mixing; Viscosity