A Helpful guide to student's Seminar presentation and richly recommended for studies and researches across the globe. the power as said is a guide and will require further research to help optimise the process of Anaerobic Digestion process of Food waste and other solid waste.

1. 1
BiomethaneProduction using
Anaerobic Digestion of Food Waste.
BY
IGBUDU SALVATION
CHEMICAL/PETROCHEMICAL ENGINEERING
DE.2015/0268
SUPERVISOR:
ENGR. JULIET BEN-IWO
JANUARY,2021

2.  Introduction:
 Background of Study,
 Aim & Objectives
 Literature review:
 Extent of Past Works
 Current work
 Materials and Methods:
 Materials, Methods,
 Framework for data analysis
 Conclusion and References
Table ofContents

3. Introduction
Backgroundof Study
 (Aghbashlo et al., 2018; Watts et al., 2018a; Watts et al., 2018b). Renewable energy sources became
significant topicof research overlast years,duetoincreased interest in environmental issues which includes
greenhouse gas (GHG) emissions and the downstream catastrophic consequences such as climate change
andpublichealthdeterioration
 Food wastes contain high amounts of moisture, volatile solids, and salinity. They are considered as the
main source of GHG emissions, unpleasant odor release, attraction of vermin, and contamination of
groundwater(Yasinet al.,2013).
 Anaerobic digestion is a natural process which occurs when organic material is kept in the absence of
air.Thereby,theorganicmaterialistransformedinto biogas,arenewable andgreenenergy.

4.  The high cost of substrate transportation, digester construction and operation, and low value of end products
are widely recognized challenges in AD of food waste
 It contaminates recyclable material in combined waste collection systems and releases methane to the
atmosphere whendeposited in landfill sites.
 Thefood wastes are estimated to have direct economic consequences.
 Methane has a global warming potential (GWP) over a 100-year time horizon of 23 times that of carbon
dioxide and is a significant contributor to climate change.
Problem Statement

5. Aimofthe Study
The aim of this study is to obtain efficient Biomethane Production from Food Waste via Anaerobic
Digestion Processes.
Objectives oftheStudy
 To evaluate the operational performance of anaerobic reactor(s) used in treating the organic fraction of food
wasteand othermunicipal solid waste.
 To determine thepotentialmethaneproduction of anaerobicdegradationof food waste.
 To develop scientific information with regard to quality and quantity of biogas from anaerobic digestion of
food waste.

6. Anaerobic Digestion takes place in airtight reactors.
 The organic fraction of the wastes is transformed into a mixture of CH4, CO2
and some trace gases (biogas).
 The produced biogas can be used either directly for cooking, heating
or lightening .
 It can also be transformed into combined heat and power (CHP) in
cogeneration plants
 Biogas can also be compressed and sold as fuel (e.g. for vehicles),
much like natural gas.
 With time the reactors fill up and digested sludge (sludge which organic
fraction was already converted to biogas) accumulates in the bottom.
 Nutrients remain in the sludge is a well-balanced fertiliser and can be used in
agriculture as a rich soil amendment.
6
AnaerobicDigestion ofFood Waste(1/2)
Introduction

7. Flow Chart ofAnaerobic Digestion of Food Waste(2/2)
Food Waste
Cooking
Lightning
Electricity
Fuel
Biogas
Heating
FertiliserAgriculture
Introduction

8. 1. Introduction
Flow Chart ofFood WasteAsanRenewable Energy Source
Co-digestion of waste
and manure
Food production at
farms
Re-use of nutrients
Re-use of energy

9. 2. Literature Review
Extent of PastWork
ResearchImprovement
In an efforttomove away from landfilling of biodegradable
the EULandfill Directive (1999)has set significant targets for reducing biodegradable waste going tolandfill
up tothe year2020.
Anaerobic Digestion of Organic Waste Started
After the discovery of methane emissions
fromnatural anaerobic habitats byVolta in 1776,
From LANDFILL to ANAEROBIC DIGESTION
19th century
it took until the end of the 19thcentury until anaerobic digestion was applied forthe
treatment
of wastewater and solid waste (Gijzen, 2002).

10. Current Work
 Hydrolisis
• Insoluble complex molecules arebroken down toshort sugars,fatty acids andamino acids.
 Fermentation(Acidogenesis)
• Products from hydrolysis are transformed into organic acids, alcohols, carbon dioxide (CO2), hydrogen (H) and
ammonia (NH3)
 Acetogenesis
• Organic acids and alcohols are converted into hydrogen (H2), carbon dioxide (CO2) and acetic acid (CH3COOH).
Therefore, oxygen is consumed andanaerobic conditions arecreated
 Methanogenesis
• Methanogenic bacteria (methanogenesis), transform the acetic acid, carbon dioxide and hydrogen into biogas.
Inthis CurrentResearch
TheDegradation oforganic material by bacteria. Inthe absence ofair
(Anaerobic).
Isstudied in Fourstages:

11. Schematic diagramofthe stages ofAnaerobicDigestion

12. Source: HOLLIGER (2008)
3.Materials andMethods.
Anaerobicdigester
1. Airtight chamber, filled with food waste
2. Anaerobic digestion takes place
3. Sludge settles on the bottom
4. Gas bubbles to the top where
it is collected
Reaction temperature is
 35 to 55 oC: mesophilic or thermophilic range
Either continuous or in batch mode:
– Batch: filled and left for digestion; After the hydraulic retention time
(HRT) emptied and filled again for a new cycle
– Continuously-stirred tank reactor (CSTR): continuous in/out flow and
mixing
– Plug-flow reactor: the sludge moves through the reactor much like a train
to a tunnel, with a velocity corresponding to the minimal HRT
The liquid phase can be re-circulated to maintain optimal moisture conditions

13. 13
Examples: Small-scale digesters
http://colli239.fts.educ.msu.edu/wp-content/uploads/2009/05/biotech2007cc.jpg
[Accessed: 04.06.2010]
Source: F. HEEB
http://images01.olx.in/ui/4/96/20/675
09620_1-Install-biotech-portable-
biogas-plants-and-convert-food-waste-
to-biogas-Vazhuthacaud.jpg [Accessed:
04.06.2010]
http://www.open2.net/blogs/media/blogs/Biogas_pla
nt_Kerala.jpg
Household
floating-drum
digesters
Portable reactors form
the Indian NGO
BIOTECH
3.Materials andMethods.

14. 14
Examples: Large-scale digesters
http://www.klima-sucht-schutz.de/mitmachen/klima-quiz/lexikon.html
[]Accessed: 04.06.2010
Source: BRUYN (2006) Source: BRUYN (2006)
Source: BRUYN (2006)
3.Materials andMethods.

15. 3.Framework for dataanalysis
To obtain the research data the following design principles are considered
Basics: Process Parameters
The biogas yield depends on the process and the substrate.
 Substrate:
– High COD (Chemical Oxygen Demand) = High potential of biogas generation
 Process:
Anaerobic digestion = Biological system of bacteria
Optimal conditions required that bacteria feel wealthy
 Temperature
• Performance
• Retention time
 pH
• Wide range, but methanogenesis requires neutrality (6.5-7.5)
• Multistage process for better pH and temperature control
 Total solid (TS) and moisture
• Wet digestion (TS < 20 %): easier to maintain, good fluidity
• Dry digestion (TS > 20 %): sophisticated but safes space
 Organi Loading Rate
• measure of the biological conversion capacity of the AD system.
• It determines the amount of volatile solids feasible as an input in the AD system. Overloading of the syste
can results in low biogas yield.

16. 16
4. Conclusion
Anaerobic digestion is a promising answer
to the soaring crises of municipal waste explosion and thus
preventing the pollution of water sources and the environnent
Biogas is an renewable energy and has the potential toreplace other fuel sources.
Biogas contributes toprevent and lower greenhouse gas emission.
Digested sludge cansubstitutechemical fertiliser
and
enhancefood production
Sustainabledevelopment:
• Improvedhealth
• Improvedeconomy

17. 5. References
BRUYN, J. de, HOUSE, H., RODENBURG, J. (2006): Ontario Large Herd Operators European Anaerobic Digestion Tour Report. Germany, Denmark and the Netherlands August 21 to 29, 2006.
Ontario Ministry of Agriculture, Food and Rural Affairs
FAO (1996): Biogas Technology - A Training Manual for Extension. Consolidated Management Services Nepal (P) Ltd. and Food and Agriculture Organization of the United Nations (FAO)
Available at: http://www.fao.org/docrep/008/ae897e/ae897e00.HTM [Accessed: 19.04.2010]
GTZ (2009): Biogas sanitation for black water or brown water, or excreta treatment and reuse in developing countries. Draft Version.(=Technology review). Eschborn: German Agency for
Technical Cooperation GmbH (GTZ) and Sustainable Sanitation Alliance (SuSanA) Available at: http://www.gtz.de/en/themen/umwelt-infrastruktur/wasser/9397.htm [Accessed:
11.03.2010]
HEEB, F. (2009): Decentralised anaerobic digestion of market waste. Case study in Thiruvananthapuram, India. Duebendorf: Swiss Federal Institute of Aquatic Science and Technology
(EAWAG). Available at: http://www.eawag.ch/organisation/abteilungen/sandec/publikationen/publications_swm/downloads_swm/ad_market_waste.pdf [Accessed: 27.04.2010]
HOLLIGER, C. (2008): Microbiologie et Biotechnologie Environnementale. Enseignements au 2iE. Swiss Federal Institute of Technologies (EPFL)
ISAT/GTZ (1999): Biogas Basics. (=Biogas Digest, Volume I). Information and Advisory Services on Appropriate Technology (ISAT) and German Agency for Technical Cooperation GmbH (GTZ).
Available at: http://www2.gtz.de/dokumente/bib/04-5364.pdf [Accessed: 19.04.2010]
MES, T.Z.D. de, STAMS, A.J.M, REITH, J.H., ZEEMAN, G. (2003): Chapter 4. Methane production by anaerobic digestion of wastewater and solid wastes. In: REITH, J.H., WIJFFELS, R.H.,
BARTEN, H.(Eds.) (2003): Biomethane and Biohydrogen. Status and perspectives of biological methane and hydrogen production. Dutch Biological Hydrogen Foundation and the
Netherlands Agency for Energy and the Environment (Novem). Available at: http://gasunie.eldoc.ub.rug.nl/FILES/root/2003/3339875/3339875.pdf [Accessed: 25.04.2010]
MUELLER, C. (2007): Anaerobic Digestion of Biodegradable Solid Waste in Low- and Middle-Income Countries. Swiss Federal Institute of Aquatic Science (EAWAG), Department of Water and
Sanitation in Developing Countries (SANDEC)
http://www.eawag.ch/organisation/abteilungen/sandec/publikationen/publications_swm/downloads_swm/Anaerobic_Digestion_high_resolution.pdf [Accessed: 27.04.2010]
MUENCH, E. (2008): Overview of anaerobic treatment options for sustainable sanitation systems. In: BGR Symposium „Coupling Sustainable Sanitation and Groundwater Protection“ 14 – 17
Oct 2008, Hannover, Germany. Eschborn: German Agency for Technical Cooperation (GTZ) GmbH Available at: http://www.gtz.de/en/dokumente/en-bgr-conference-biogas-ecosan-
muench-2008.pdf [Accessed: 23.04.2010]
OSTREM, K. (2004): Greening Waste: Anaerobic Digestion for treating the organic Fraction of Municipal Solid Wastes. Master theis. Colombia: The Fu Foundation of School of Engineering
and Applied Science, Columbia University
PIPOLI, T. (2005): Feasibility of Biomass-based Fuel Cells for Manned Space Exploration. In: Proceedings of the Seventh Eurpean Space Power Conference, Stresa, Italy. 9 to 13 May 2005.
VOEGELI & LOHRI 2009)
VOEGELI, Y., ZURBRUEGG, C. (2008) Biogas in cities - A New Trend?. In: Sandec News, Vol. 9/2008. Duebendorf: Swiss Federal Institute of Aquatic Science (EAWAG)
WRAPAI (2009): Document 8, Data Management Document, Appendix S 06 - Energy Research. Australia: Waste Refinery Australia Project Association Incorporated (WRAPAI) Available at:
http://www.members.iinet.net.au/~nwk/wrapai/wr_se8_app_s06_energy.pdf [Accessed: 03.05.2010]
YADAVA, L. S., HESSE, P. R. (1981): The Development and Use of Biogas Technology in Rural Areas of Asia (A Status Report 1981). Improving Soil Fertility through Organic Recycling. (=Project
Field Document No. 10.). Food and Agriculture Organization (FAO) and United Nations Development Programme (UNEP)