Abstract—Municipal wastewater treatment plants generate
large amounts of sludge after a set of unit processes. The sewage
sludge is an important resource for energy production because
of its high level of biodegradability. Sewage sludges are
generally made of non-toxic and biodegradable organic
compounds mixed with a small fraction of non-toxic and toxic
inorganic compounds having a very low biodegradability. The
large fraction of biodegradable matter constitutes a pool for
green/clean energy to be used for industrial and domestic
applications. The generated energy can also be used in the
wastewater treatment plant. Currently, fossil fuels are leading
the energy world, however, they are being depleted and are
considered to be among the main causes contributing to climate
change and global warming. Domestic sewage sludge can be
converted sustainably into bio-hydrogen and bio- methane.
This conversion is achievable through anaerobic digestion,
combustion, pyrolysis and gasification. With regard to the last
three conversion processes, the organic and inorganic toxic
compounds are eliminated. Production of biogas from sewage
sludge is being undertaken worldwide on small, medium, and
large scales. However, hydrogen production from sludge is still
developing. There is an existence of substantial knowledge in
this field, the production of hydrogen and biogas from sewage
sludge is gaining interest. This study analyses various
possibilities of sewage sludge conversion into clean energy. The
analysis focuses on the technology strengths, weaknesses and
gaps to be improved in future studies.
Index Terms—Domestic sewage, sludge, biogas, bio-methane, bio-hydrogen, anaerobic digestion.
Joseph K. Bwapwa is with Mangosuthu University of Technology, Department of Civil Engineering, Faculty of Engineering, Durban, Umlazi, 4001, South Africa (e-mail: firstname.lastname@example.org, email@example.com).
Cite: Joseph K. Bwapwa, "Overview on Bioconversion of Domestic Wastewater Sewage Sludge into Green Energy: Biogas and Hydrogen," International Journal of Environmental Science and Development vol. 12, no. 8, pp. 232-241, 2021.Copyright © 2021 by the authors. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).