Environmental Engineering Reference
In-Depth Information
of VFA are neglected. In a COD-based mass balance, this means that degraded
COD material is converted into methane COD.
3. From the data obtained in the biodegradability survey, estimate the inert fraction
of the organic substrate (
f
I
) and the first-order rate coefficient for hydrolysis of the
biodegradable fraction of the organic substrate (
k
h
). Discuss the results obtained.
By identifying the biodegradable fraction of the substrate and the hydrolysis
rate coefficient, we can design a continuous stirred tank bioreactor. The extent
of degradation of the substrate we want to achieve is the main variable in
the design of the process, and we therefore aim our design at achieving
60, 70, 80, 90, or 95% degradation of the biodegradable fraction of the substrate
to biogas.
4. Estimate the retention times and reactor volumes required to obtain the required
degrees of degradation.
5. Estimate the potential biogas production (m
3
.h
−1
) and the biogas composition
(vol.% CH
4
and vol.% CO
2
).
6. Estimate the electricity production (MW) that can be obtained from the biogas
in a CHP plant.
7. Discuss the results obtained in terms of the volume required versus the electric-
ity production.
8. Discuss the additional technology and measures that are needed for successful
implementation of the process. Think about pretreatment methods or technol-
ogies for nutrient recovery, heat integration, etc.
REFERENCES
Batstone DJ, Keller J, Angelidaki I, Kalyuzhnyi SV, Pavlostathis SG, Rozzi A, Sanders WTM,
Siegrist H, Vavilin VA.
Anaerobic Digestion Model No. 1 (ADM1)
. London: IWA publish-
ing; 2002.
Heijnen JJ, Kleerebezem R. Bioenergetics of microbial growth. In: Flickinger MC, editor.
Encyclopedia of Industrial Microbiology: Bioprocess, Bioseparation and Cell Technology
.
Volume 1, New York: John Wiley & Sons, Inc.; 2010. p 594-617.
Kleerebezem R, Van Loosdrecht MCM. Waste characterization for implementation in ADM1.
Water Sci Technol 2006;54(4):167-174.
Nasir IM, Ghazi TIM, Omar R. Anaerobic digestion technology in livestock manure treatment
for biogas production: a review. Eng Life Sci 2012a;12(3):258-269.
Nasir IM, Ghazi TIM, Omar R. Production of biogas from solid organic wastes through anaer-
obic digestion: a review. Appl Microbiol Biotechnol 2012b;95(2):321-329.
Tilche A, Galatola M. The potential of bio-methane as bio-fuel/bio-energy for reducing green-
house gas emissions: a qualitative assessment for Europe in a life cycle perspective. Water
Sci Technol 2008;57(11):1683-1692.
van Lier JB, Mahmoud N, Zeeman G. Anaerobic wastewater treatment. In: Henze M, Van
Loosdrecht MCM, Ekama GA, Brdjanovic D, editors.
Biological Wastewater Treatment
Principles, Modelling and Design.
London: IWA Publishing; 2008. p 401-442.
Search WWH ::
Custom Search