Mentore Vaccari, Francesco Vitali

CeTAmb, UNIVERSITY OF BRESCIA

Solid waste disposal of1

Current status

Why is controlled waste disposal important?2

Stages in the SWM system

Waste disposal: options

Non-engineered disposal

• systems without any control, or with only slight or

moderate controls

• in place for many years

• high environmental and health costs

Sanitary landfilling

• fully engineered disposal option

• wastes spread, compacted and covered

• land carefully engineered before use

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Stages in the SWM system

Common disposal methods in DCs

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Disposal practicePrimary

collectionSecondary collection

Designatedplaces

Operation at the site

Waste discarded at source NO NO NO NO

Uncontrolled local disposal YES NO NO NO

Uncontrolled city disposal YES YES NO NO

Semi-controlled disposal YES YES YES NO

Controlled disposal YES YES YES limited

Fully-engineered disposal YES YES YES YES

What is a landfill?

It is not just a place where waste is disposed of, but it is a technologicalplant designed, realized and managed to obtain a minimization of negativeeffects

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4 basic conditions:

full or partial hydrogeological isolation

formal engineering preparations

permanent control

planned waste emplacement and covering

Source: Rushbrook and Pugh, 1999

Sanitary landfilling is a fully engineered disposal option that avoids theharmful effects of uncontrolled dumping by spreading, compacting andcovering the waste on land that has been carefully engineered before use.

Types of landfills6

Hill shaped • No digging costs• High visual impact • Facilitated flowing of

leachate and storm water

On a slope • Low stability of waste• Facilitated flowing of

leachate and storm water

In a depressionsite

• Reduced visual impact• Difficult drainage of

leachate and storm water

Location of landfill sites

Inappropriate areas:

• Closer to populated area

• Drinking water protection areas (wells, superficial basins, rivers)

• Unstable ground

• Areas subjects to overflowing

Preferable areas (positive areas)

• Soil with low permeability

• Possibility of continous gravity drainage for leachate from waste

• Presence of access roads

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Final cover of landfills

A final cover allows to:

• limit infiltration of storm water in the waste (reducing leachateproduction)

• recover the area , reintegrate it into the landscape, and prepare the area to a future use

How to limit the production of leachate?

• Modelling the slope in order to increase water runoff

slope > 5-10%

• Placing an impermeable layer (compacted clay > 30 cm) in order to limit infiltration of rain water into the waste

Construction in cells

• reduce capital investment costs

• lower amount of leachate

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Control of leachate

(Jamarillo, 2008)

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Gaseous emissions

(Jamarillo, 2008)

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Gaseous emissions

(Jamarillo, 2008)

Types of landfill

Mechanized sanitary:

Large cities and populations (>40 tons daily)

It requires technical planning, control of operations, large investements, heavy equipment dedicated

Semi-mechanized:

Towns (16-40 tons daily)

Use heavy machinary to support the manual

labour (garbage compaction and banks

stabilization)

Manual:

Small communities (<16 tons daily)

Compacting and confining of waste carried out by a team of laborers usinghand tools

Adapted from Jaramillo (2003)

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Semi-mechanized sanitary landfills

1. Waste download

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30 cm

2. Waste spreading

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Semi-mechanized sanitary landfills

3. Compaction

At least 5 times

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Semi-mechanized sanitary landfills

2 m

4. Waste windrow formation

Embankment

N

EMBANKMENTS 2 m HIGH

EMBANKMENTS 0.8 m HIGH

DRAINING CANAL

(HYPOTHESIZED LOCATION)

GUARDIAN

BUILDING

ENTRANCE

DRAINAGE AREA

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Semi-mechanized sanitary landfills

4. Waste windrow formation

Every day put a 10 cm layer of earth over the waste windrow!!

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Semi-mechanized sanitary landfills

5. Daily earth coverage

At least 5 times

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Manual sanitary landfills

5. Earth coverage compaction

Main interventions for the construction or rehabilitation of 7 disposal sites

• Levellement of access roads

• Construction of a simplified system for

collection of rainwater and leachate

(draining channels + evaporation basin)

• Building of embankments

• Shaping of the bed of the landfill

• Building of warehouses

Semi-mechanized sanitary landfills: a case study from Somaliland

Before After

Boroma disposal site

Semi-mechanized sanitary landfills: a case study from Somaliland

Boroma disposal site

Semi-mechanized sanitary landfills: a case study from Somaliland

Semi-aerobic landfill23

• Waste in aerobicconditions: bacteriaactivity convertsbiodegradablematter in H2O and humus

• Perforated pipes to collect leachate and supply air into the waste

• Stack effect due to heat produced by bio-degradation exothermic reactions (50-70°C)

Semi-aerobic landfill

The aerobic degradation of MSW within a landfill can :

1. significantly increase the rate of waste decomposition and settlement,

2. decrease the production of methane gas and odours

3. reduce the level of toxic organics in the leachate

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Vertical pipes have to be installed in order to increase the aerated portions of wastes

Principal pipe

Drainage

Vertical pipe

Drainage

Unload

leachate

Leachate collection basin

Semi-aerobic Landfill site

Advantages of Semi-aerobic Landfill Type

• Leachate is discharged as soon as it is collected - reduce the seepage of leachate

• Fresh air is brought in from the pipes - enhance waste stabilisation, improve leachate quality and reduce the cost of final treatment of leachate

• Release gas from gas ventilation pipes - reduce gas pressure and the chance of gas explosion

• Compaction of waste - reduce land consumption

• Enhance waste stabilisation - less time requires for the reuse of completed landfills (for vegetation, open space, parks, recreation, school, etc.)

• Reduce of CH4 and increase of CO2 helps preventing the global warming

• Cost-effective as initial investment and maintenance cost of Semi-aerobic is lower than that of Aerobic type of landfill

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Semi-aerobic landfill

Semi-aerobic Landfill site

From Dr. Matsufuji. Fukuoka Univ. «Semi Aerobic Landfill Site story» «Mizu» Jan&Feb 1998)

Local materials could be used to realize leachate collection and gas venting pipe

Management of semi-aerobic landfills

• Wastes are disposed in layers with a thickness not more than 1 m

• Daily cover with soil (not clay) > 15 cm to avoid:

• Bad smell

• Vermins and pests

• Scattering of light waste by wind

• A new layer has to be disposed when the aerobic fermentation in the layer below has ended (a few months)

• Soil final cover > 50 cm

Further reading

Abu Qdais H. A. (2007): “Techno-economic assessment of municipal solid waste management in Jordan”, Waste Management, Vol. 27, pp. 1666-1672

Agamuthu P. and Fauziah S.H. (2010): “Challenges and Issues in Sustainable Landfilling in a transitory country-Malaysia”, Proceedings of the First International Conference on Final Sink From Sanitary to Sustainable Landfilling: why, how, and when, Vienna, Austria, 23rd-25th September 2010

Ali A. (2010): “Wasting time on solid waste in developing countries”, Waste Management, Vol. 30, pp. 1437-1438

Ali S. M. (2004): “Sustainable composting: Case studies and guidelines for developing countries”, Water Engineering and Development Centre, Lougborough University, Loughborough, ISBN: 1 84380 0713

Ali S. M. (2010b): “Key Issues and Approaches in Solid Waste Management in Developing Countries”, Series of Workshops, CeTAmb, University of Brescia, September 2010, available on http://www.ing.unibs.it/~cetamb/seminari

Ali S. M., Cotton A. P. and Westlake K. (1999): “Down to earth”, Water Engineering and Development Centre, Lougborough University, Loughborough, ISBN: 0 906055660

Ali S. M. and Cotton A. P. (2000): “Process of change in solid waste management – Briefing note”, Water Engineering and Development Centre, Lougborough University, Loughborough, ISBN: 92- 807-2676-5

Ball J., Grobbelaar L. and Cisse O. (2007): “Scavenging on landfills and dumpsites: an African perspective”, Proceedings of Sardinia Conference 2007 11th International Waste Management and Landfill Symposium 1st-5th October 2007, S. Margherita di Pula (Cagliari)

Baud I, Post J. and Furedy C. (2004): “Solid waste management and recycling – Actors, partnerships and policies in Hyderabad, India and Nairobi, Kenya”, Kluwer Academic Publisher, London

Coad A. (1994): “Managing medical wastes in developing countries”; Report of a Consultation on Medical Wastes Management in Developing Countries, WHO, Geneva, September 1992

Cointreau S. (1982):. “Environmental Management of Urban Solid Waste in Developing Countires – A project guide”, Urban Development Department, The World Bank, Washington.

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Further reading

Cointreau-Levine S. (1997): “Project Preparation: Solid Waste Management, Section IV”, in Urban Waste Management Guidelines. Tools, and Practices in Sub-Saharan Africa, ed. Obeng L. & Cointreau- Levine S., Infrastructure Family, Africa Region, The World Bank

Collivignarelli C., Sorlini S., Cavallari S. and Vaccari M. (2003): “Waste management and recovery in the developing Countries”, Proceedings of Sardinia 2003, 9th International Waste Management and Landfill Symposium, S. Margherita di Pula (CA), Italy, 6th-10th October 2003

Collivignarelli C., Vaccari M., Di Bella V. and Giardina D. (2010): “Techno-economic evaluation for the improvement of MSW collection in Somaliland and Puntland”, Waste Management & Research, doi: 10.1177/0734242X10384431

Dhamija U. (2006): “Sustainable solid waste management – Issues, policies and structures”, Academic Foundation, New Delhi

Diaz L.F., Savage G.M. and Eggerth L.L. (2007): “The management of solid wastes in economically developing countries – major needs”, Proceedings of Sardinia 2007 11th International Waste Management and Landfill Symposium, 1st-5th October 2007, S. Margherita di Pula (Cagliari)

EEA (2009): “Waste without borders in the EU? Transboundary shipments of waste”, European Environment Agency Report 1/2009, available on http://www.eea.europa.eu/publications/wastewithout-borders-in-the-eu-transboundary-shipments-of-waste

Frisch K. C. (1999): “Advances in Plastic Recycling - vol. 1”, Technomic Publishing, ISBN: 1-56676- 737-1

Imam, A., Mohammed, B., Wilson, D.C, & Cheeseman, C.R. (2008): “Solid waste management in Abuja, Nigeria”, Waste Management, Vol. 28, pp. 468-472

Jaramillo J. (2003): “Guidelines for the design, construction and operation of manual sanitary landfills - A solution for the final disposal of municipal solid wastes in small communities”, Pan American Center for Sanitary Engineering and Environmental Sciences, Lima

Johannessen L. M. And Boyer G. (1999): “Observations of Solid Waste Landfills in Developing Countries: Africa, Asia, and Latin America”, Urban Development Division Waste Management Anchor Team, The World Bank, Washington

Lardinois I. and van de Klundert A. (1995): “Plastic Waste – Options for small-scale resource recovery”, TOOL publications, Amsterdam

LVIA (2009): “Proteggere l’ambiente valorizzando i rifiuti - La gestione dei rifiuti plastici nelle città africane (To protect the environment by using waste – Plastic waste management in African cities)”, Torino

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Further reading

McDougall F. R:, White P., Franke M. and Hindle P. (2001): “Integrated solid waste management: a life cycle inventory”, Blackwell Publishing, Oxford

Medina M. (2000): “Scavenger cooperatives in Asia and Latin America”, Resources, Conservation and Recycling, Vol. 31(1), pp. 51–69

Mwai M., Siebel M. A., Rotter S. and Lens P. (2008): “Integrating MDGs in the Formulation of Strategies for Solid Waste Management – A Life Cycle Approach”, WaterMill Working Paper Series 2008, no. 15

Nagendran R., Kurian J. and Esakku S. (2010): “Municipal Solid Waste Dumpsites To Sustainable Landfills”, available on http://www.faculty.ait.ac.th/visu/Prof%20Visu's%20CV/Journals/18/19.pdf

Oman C. and Raj Manandhar (2010): “Proposed actions for landfill improvements in economically developing countries”, Proceedings of the First International Conference on Final Sink From Sanitary to Sustainable Landfilling: why, how, and when, Vienna, Austria, 23rd-25th September 2010

Peterson C. (2009): “Key Planning Factors for Waste Sector in Developing Countries”, Presentation from ISWA Beacon Conference Strategic Waste Management Planning, Novi Sad, Serbia, 10th-11th December 2009

Plastic Waste Management Institute (2004). “An Introduction to Plastic Recycling”, Plastic Waste Management Institute, Tokyo

Prüss, A., Giroult, E. and Rushbrook, P. (1999): “Safe management of wastes from health-care activities”, Geneva, World Health Organization, ISBN 92 4 154 525 9

Rothic K. H., Yongsheng Z. and Jun D. (2006): “Municipal solid waste management challenges in developing countries – Kenyan case study”, Waste Management, Vol. 26, pp. 92-100

Rouse J. R. (2006): “Seeking common ground for people: Livelihoods, governance and waste”, Habitat International, Vol. 30, pp. 741-753

Rushbrook P. and Pugh M. (1999): “Solid Waste Landfills in Middle- and Lower-Income Countries”, Urban Development Division Waste Management, The World Bank, Washington, USA

Rushbrook P., Chandra C. and Gayton S. M. (2000): “Starting healthcare waste management in medical institutions – a practical approach”, Copenhagen, Practical Health care Waste Management Information Series No. 1, WHO Regional Office for Europe, EUR/00/5021817

Salem S. M., Lettieri P. And Baeyens J. (2009): “Recycling and recovery routes of plastic solid waste (PSW): A review”, Waste Management, Vol. 29, pp. 2625-2643

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Further reading

Smith Korfmacher K. (1997): “Solid waste collection systems in developing urban areas of South Africa: an overview and case study”, Waste Management & Research, Vol. 15, pp. 477–494.

UNEP (2004): “Waste Management Planning - An Environmentally Sound Approach for Sustainable Urban Waste Management - An Introductory Guide for Decision-makers”, United Nations Publications, ISBN 92-807-2490-8

UNEP (2005): “Solid Waste Management”, CaRecovery, ISBN: 92-807-2676-5

UN-Habitat (2010): “Solid Waste Management in the World’s Cities - Water And Sanitation In The World’s Cities 2010”, Earthscan, London, ISBN 978-1-84971-169-2 hardback

Vaccari M. (2007): “The management of municipal solid waste in developing countries: a brief overview”, Proceedings of the conferenceCooperazione internazionale allo sviluppo: soluzioni appropriate per ambiente, energia e sviluppo sostenibile 23rd-24th October 2007, Vogler J. (1984): “Small-scale recycling of plastics”, Intermediate Technology Publications, London

WASTE and SKAT (2007): “Economic Aspects of Informal Sector Activities in Solid Waste Management”, Final Report 2007, Waste, Skat, Reference Number 81084644

WASTE and SKAT (2010): “Economic Aspects of Informal Sector Activities in Solid Waste Management”, Main Report 29 October 2010

WEDC (2010): “Solid Waste Management”, Handouts from postgraduate module on solid waste management, Loughborough University, Loughborough

WHO (1999): “Safe management of wastes from health-care activities”, available on http://www.who.int/water_sanitation_health/medicalwaste/wastemanag/en

WHO (2005): “Managing Health Care Waste Disposal – Guidelines on how to construct, use and maintain a waste disposal unit”, Washington

Wilson D., Whiteman A. and Tormin A. (2001): “Strategic planning guide for municipal solid waste management”, World BanK, Washington, DC, available on http://www.worldbank.org/urban/solid_wm/erm/start_up.pdf

Wilson D. C., Velis C. and Cheeseman C. (2006): “Role of informal sector recycling in waste management in developing countries”, Habitat International, Vol. 30, pp. 797-808

Zurbrügg C. (2003): “Solid Waste Management in Developing Countries”, available on http://www.eawag.ch/

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