report group 3. pdf

8/8/2019 Report Group 3. PDF

http://slidepdf.com/reader/full/report-group-3-pdf 1/11

Large Technical Systems and the Environment

Linköping Universitet,

SE‐581 85 Linköping, Sweden Linköping 2009

Incineration as a waste recycling strategy in developing countries;

the case of Accra, Ghana

Mesfin TayeWisdom KandaMd Toufiqur RahmanFrancis Atta KuranchieSiva Kalyan Varma Pinama Raju

SUPERVISOR: MICHAEL MARTIN



SummaryIn a developing country like Ghana low cost energy sources would serve in the best interestof economic development. This can be achieved by changing the content of the nationalenergy supply from conventional expensive sources to cheaper, renewable andenvironmentally friendly sources.

Increasing waste generation remains a persistent problem. A salient waste managementproblem is that responsible municipal assemblies have allocated a marginal portion of funding for this purpose. Waste management methods employed such as open air burning,public dumps and land filling are problematic because of their inherent environmental issues.Other barriers to sustainable waste management include unavailable correct data on thequantity and characteristics of waste generated and its specific impacts on the environment.Coupled with the above are problems of low level technology and the perception that wastemanagement is a less important large technical system compared with other municipal

services.The project work addresses the environmental impacts of incineration with energy recoveryof municipal solid waste as a recycling strategy in a developing country and discusses thefeasibility of implementing such a solution. The results indicate that incineration with energyrecovery is a better alternative to the current waste management systems in place from anenvironmental point of view. For a feasible integration of the system there needs to beadjustments in the current waste management practices to incorporate issues such as sourcesorting and other measures to prevent incineration of toxic waste.



Table of ContentsINTRODUCTION ....................................................................................................................................... 1

1.1 Background ................................................................................................................................... 1

1.2 Aim ................................................................................................................................................ 1

1.3 Scope ............................................................................................................................................. 1

2.0 METHOD ............................................................................................................................................ 1

3. 0 RESULTS ............................................................................................................................................ 2

3.1. Waste management and collection in Accra, Ghana. .................................................................. 2

3.1.1 Municipal solid waste composition in Accra, Ghana ............................................................. 2

3.1.2 Solid waste management in Accra, Ghana ............................................................................ 3

3.1.3 Solid Waste Collection ........................................................................................................... 3

3.1.4 Solid waste disposal ............................................................................................................... 4

3.2 Energy crises ................................................................................................................................. 4

4.0 DISCUSSION ....................................................................................................................................... 5

4.1 Environmental impact of waste .................................................................................................... 5

4.2 Feasibility of Incineration as a waste management system ......................................................... 5

4.3 Environmental impact of incineration plant ................................................................................. 6

5.0 CONCLUSION ..................................................................................................................................... 7

6.0 REFERENCES ...................................................................................................................................... 7



1

INTRODUCTION

1.1 Background

Ghana is booming with economic activities. With a corresponding increase in population andcommercial activities there has been persistent issues about large volumes of waste generatedwhich is left untreated. With an average waste generation rate of 0.7kg/cap/dayenvironmental degradation has become a threat (Tsiboe and Marbell, 2004). The other side of the coin also is the continuous energy crisis which hit the country when there is shortage of rainfall due to over reliance on hydropower.

With the current energy supply being contributed by 10% hydropower, 30% fossil fuel and60% wood (Kermausuor and Brew, 2007) many issues within energy sector remain a puzzle.Are these trees cut down for charcoal production being replaced through replanting? Whatare the environmental implications of the burning of this forest biomass?

As has always been the case the answer to this questions lies within the problem. Largeamount of municipal waste is generated daily in the major cities in Ghana which are eitherleft untreated to decompose at landfills or burnt openly.

1.2 Aim

The aim of the project is to evaluate incineration with energy recovery as an environmentallysustainable way of municipal waste management in developing countries by taking Accra,Ghana as a system for study. Is the waste being generated in developing countries plenty andgood enough to run a proposed incineration plant without requiring an extra fuel (burners)?From an environmental perspective, what advantages would incineration have over simplewaste littering and land filling?

1.3 ScopeThe project work takes an in depth look into municipal waste generated in developingcountries and how incineration with energy recovery can be used as a means to solve theenvironmental challenge and also produce energy.

2.0 METHODThe internet, library and conference proceedings were the main source for gatheredinformation.

For an effective output, the project work was divided into the following major sections andeach member of the group conducted an in depth research on a particular section.

Municipal solid waste definition and classification

Incineration with energy recovery



2

Environmental impacts of incineration as a waste management strategy

The possibility and challenges of integrating incineration with energy recovery indeveloping countries.

From a critical review of gathered information, followed with discussions among the project

group, deductions and conclusions are drawn in line of the project aim.

3. 0 RESULTSWaste is any substance or objects the holder castes away, intends to caste away or is requiredto caste away because the holder considers it to be of no use.

Waste classification is generally based on the material state as solid, liquid, gas andradioactive; its general toxicity inert, hazardous and general waste; and its source asmunicipal, industrial or agricultural waste. From municipal point of view it can be defined as

waste emanating from households, as well as other waste, which, because of its nature orcomposition, is similar to waste from households (EU).

3.1. Waste management and collection in Accra, Ghana.

3.1.1 Municipal solid waste composition in Accra, GhanaAccra produces about 760,000 tons of municipal solid waste (MSW) per year orapproximately 2000 metric tons per day (EPA, 2002). These are estimates and the real valuesare probably more than these quantities. The municipal waste stream is composed of domestic such as food waste, garden waste, sweepings, ash, packaging materials, textiles and

electric and electronic waste. Industrial waste include metals, wood, textiles, plastic; foodwaste from slaughter houses, cocoa processing factories, fruit processing and grain mills.Commercial activities generate waste with high food and plastic contents while waste paperwhich is about 4.2% of MSW comes from schools and offices. As depicted inFigure 1, the waste stream has a largely organic based which is contributed by households.

Figure1. Municipal waste composition in Accra (Data AMA, 1993) ( Source : Kramer et al,1994).



3

3.1.2 Solid waste management in Accra, GhanaThe approach to municipal solid waste management has been characterized by unplannedsolutions such as: mobilizing people to collect waste and de-silt chocked gutters after a flooddisaster; temporal allocation of waste collection contracts and damping or building a central

solid waste composting plant. The fact to the issue is that stakeholders trying helplessly tosolve this issue need to work in a collaborative effort with a rather proactive systemsperspective. No single solution can totally solve the problem.

Typically waste disposal and management is largely the responsibility of the municipalassembly. The amount of waste generated far exceeds the collection capacity of the municipalassembly. The municipal assembly provides containers at car packs, streets, commercial andinstitutional areas for waste collection. This waste is simply dumped into the containerswithout any form of source sorting. The municipal assembly conveys these containers when

full to public landfills. The remaining waste is handled by individual households either byburning or burying in the ground.As depicted in the Figure 2 below public dump is employed as the main waste disposalamounting 54% of the current Accra waste management system, followed by otherenvironmentally hazardous methods such as open air burning and burying by individualhouseholds.

Figure 2. Waste disposal methods in Accra (Data AMA, 1993) ( Source : Kramer et al, 1994).

3.1.3 Solid Waste CollectionThe city has been divided into waste collection zones where a private waste collectioncompany is contracted to collect waste on behalf of the municipal assembly. The waste istaken by road directly to the disposal sites. A house-to-house collection of household wastealso exists in well planned communities in the municipality. Residents pay waste collectioncompanies which then pay Accra Municipal Assembly (AMA) for using their dump sites for

disposing off their waste.



4

In low income communities there is a centralised waste collection system in which residentsdisposes off their waste into a container which is collected for disposal weekly. Residents donot pay any fee for such an activity.Despite these strategies, fractions of the waste as can be seen in Table 1 remain uncollected.

Table 1. Average waste collection over the past 6 years. Data, AMA waste management

department ( Source : Dotseh Anomany, 2004)

Table 1: Volume and Dailytonnage of waste collected inAccra over the past 6 years.Year

Average tonnagegenerated/day

Average tonnagecollected/day

1998 750 450 - 600

1999 960 600 -800

2000 1650 1200 – 1500

2001 1700 1300 - 1500

2002 1720 1300 – 1500

2003 1800 1300 – 1500

The disposal system is characterized by inappropriate location of disposal sites coupled withuncontrolled and ecologically harmful land filling. At present, the dumping grounds are notengineered to serve as sanitary landfill sites. They therefore constitute high potential for thespread of infections through run offs during rains and contamination of underground water.

3.1.4 Solid waste disposalSolid waste is disposed off at landfills or dumping grounds marked with bad ecologicaloutputs. The outcome serves a high potential for leaching of infections and toxic waste tocontaminate underground water sources.

3.2 Energy crisesPersistent crises of energy production have become major problem of people of Ghana. Asthe case is in most developing countries, electrical power production in the country has longbeen on shoulder of hydro-dam system that accounts for 10% of the energy source. Electricpower production of a hydropower plant is directly connected with distribution and intensityof rainfall in any given season. A recent energy system analysis showed a recurring failure of the hydro-dam systems to meet the electricity demand. And the rain has been blamed to havecaused these crises that pulled down the young economy of Ghana by 2.2% over a singleyear. (Kermausuor and Brew, 2007) Furthermore, forest wood is being used as source of energy that fuels 60% of household, commercial and in some cases industrial energy

demands. And this clearly poses a key problem on the forest reserve and regional climatechange. The remaining 30% of energy demand gets its segment from petroleum. A



5

cumulative overlook on the energy sources of Ghana puts the country amongst those with ahigh risk susceptible energy system.

4.0 DISCUSSION

4.1 Environmental impact of wasteAt present, no planned disposal system is devised in most developing countries to bettermanage the generated waste. Same case holds in Accra, Ghana. Waste is seen litteredeverywhere within the vicinity of the city. Public dumping sites are not under properutilization. Besides, burning of waste in these public damping sites is becoming a commonincidence. Eventually, these contributes to environmental damages such as deposition of toxic waste gases to the atmosphere, degradation of beautiful outlook of the municipality,chocking of drainage systems which further causes flooding during the rain seasons. Theflooding becomes a convenient place for breeding of diseases such as malaria, diarrhoea and

dysentery, and also this waste at major stake could degrade the quality of soil structurecausing problem to the agriculture of the country.

Several proposals have been presented by various researchers and institutions in relation tosustainable ways of waste handling in developing countries. This study paper considersincineration with energy recovery technology as a possible solution. The case of Accra,Ghana has been taken as a sample to evaluate the practicality of integrating the technology asa waste management strategy in a developing country.

4.2 Feasibility of Incineration as a waste management systemIncineration is a thermal waste treatment process which involves the combustion of waste athigh temperatures in the presence of oxygen. Waste is collected and transported to anincineration plant. In the incinerators, Combustion of waste at a temperature of 800 oC andabove is performed which results in a tremendous amount of heat energy. By-products of thisprocess mostly include bottom ash, particulates and flue gases such as CO 2, CO, N xO, SO x.

At the outset, an incineration plant needs a well organized waste collection system. In mostdeveloping countries such as Ghana, waste collection is often highly inefficient as thecollection workers are untrained, underpaid, poorly encouraged, and have no or limitedaccess of tools and vehicles that could facilitate the task. Efficient collection, transportationand disposal of waste should be enacted ahead of the project implementation to guarantee asmooth flow of waste to the plant during operation.

An essential consideration while analysing project feasibility of a waste incinerator is nature(composition) of the waste and its calorific value. Due to the socio-economic status in manylow to middle level income countries, amount of highly combustible resources in the waste islimited. Less organized and informal recycling activities in the waste handling system alsotend to further reduce the amount of paper, cardboard, and plastic composition of the waste.

Moreover, the waste is prone to high ash and moisture content which apparently reducescombustibility. Municipal solid waste in such areas therefore often falls under a low calorific



6

value and its ability to burn without auxiliary fuel (burners) is uncertain. However, industrial,commercial, and institutional wastes (except from market source) have significant calorificvalue. According to a conducted research, the mean gross calorific value of waste in Accra is16.85MJ/Kg and has an average moisture content of 62.2% by weight. (Fobil et al, 2005),Thus, certain measures need to be taken to make incineration possible in countries likeGhana. Mixing wastes of different source is one mechanism to raise and meet the lowestpermissible calorific value of junk that must reach to incinerators. Lower calorific value muston average be at least 7 MJ/kg, and must never fall below 6 MJ/kg in any season. (Fobil et al,2005)

More over, incinerators are one of the most expensive choices of waste management systemsas they require a high maintenance and operation cost (World Bank, 1999). For a plant to beeconomically feasible, Expense must be supported by income such as selling of generatedenergy. Political and socio-economic considerations play a vital role at the time of fixing theprice of waste-generated energy. A high price resulting in a reduction of the waste tipping fee

favours the waste sector, and low energy prices favour the energy consumers.

4.3 Environmental impact of incineration plant‘The incinerator industry promotes that incinerators are having zero emissions so they aresafe for community and environment but the truth is all incinerator emits dangerouscompounds like dioxins and other pollutants that contaminate our land, air and water.’ GlobalAlliance for Incinerator Alternatives (GAIA, 2008).

Emissions from incinerators include heavy metals such as lead, arsenic and mercury, acidgases, and also volatile hydrocarbons such as dioxins and furans. Mixing of toxic materials athigher temperatures form dioxins and furans. Health impacts of dioxins includes cancer, birtheffects, diabetics, immune system damage and etc, but the highest risk goes to childrenbecause concentrated dioxin passes from mother to child while breast feeding. Incineratorworkers also face high risk even though they are provided with standard protectiveequipment. Particles called ultra-fines or nano-particles cause for concern about incineratoremissions of dioxin and other toxins. The size of ultra fine particles ranges from 1 to 100nano-meters making them difficult to capture with pollutant filtering devices. These ultra-fines account 1-5 percent of all airborne particles in urban air. (GAIA, 2008) Besides thepollutants coming from air it is also important to look at other outputs which are coming outfrom incinerators.

In addition to these toxic gas emissions, incineration has also a solid waste, though reducedby 45% from the original volume, which needs to be land filled. Air pollution control devicesin incinerators capture and concentrate the toxic pollutants, but they don’t totally eliminatethem. These concentrated toxic substances are intermittently collected and disposed off inlandfills. At some point landfills will leak and then toxic pollutants will leach into soil and

ground water thereby polluting ecosystems and communities.



7

5.0 CONCLUSIONAn ingenious solution that reduces impact of generated waste in developing countries likeGhana is a must to work on. Prior to execution of any waste based projects such asincinerators, well organized waste collection and handling system need to be realized. Thisbegins from merger of good waste disposal culture in daily lives of the people. Amongst all,

obtained data on waste composition and quality (calorific value) of Accra portrays apossibility of erecting an incineration plant. But, much is needed to be done towardsimproving the waste disposal culture of the people. Though is hard to generalize overexistence of similar conditions in all developing countries, it is more likely to have samepattern to that of Accra, Ghana.

Such energy production plant therefore consumes unwanted waste and generate tremendousamount of heat energy. From what has been observed on the current energy demand of Ghana, a proposal of generated heat for electricity production and industrial steam supplywould not be a vague preference. The obtained heat energy can further be utilized for

purposes such as providing hot tap water for consumers, space heating and cooling, e.t.c.Besides, the plant also reduces the amount of waste which should have been sent to landfillsotherwise. By doing this, emission of GHG (Green House Gases) such as methane andleaching of toxic materials from landfills is highly reduced.

To better effect environmental friendliness and validity of incineration plant over land filling,techniques which reduce emission of toxics from incinerators need to be thought up.Provision of end of pipe technologies which traps fly ashes, toxic gases and flue gases makesthe plant more effective in terms of reduced emission . Simultaneously, similar techniquesneed to be adopted in places where bottom ash is disposed.

6.0 REFERENCES

1. Dotseh Anomany, E. (2004). ‘ Integration of municipal solid waste management inAccra (Ghana): bioreactor treatment technology as an integral part of the managementprocess’ Master of Science Thesis, International Environmental Science, LundUniversity, Sweden.

2. Environmental Protection Agency (2002). Ghana’s State of the Environment Report

3. Fobil, J.N., Carboo, D. And Armah, N.A. (2005). ‘Evaluation of municipal solidwastes (MSW) for utilisation in energy production in developing countries’, Int. J.

Environmental Technology and Management , Vol. 5, No. 1, pp.76–86.

4. Incinerators Trash Community Health Global Alliance for incinerator Alternatives(GAIA) www.zerowarming.org [email protected] June, 2008) [Accessed: 9 Nov.2009]



8

5. Kermausuor, F. and Brew-Hammond, A. (2007). Energy crises in Ghana.

6. Kramer, H., Jechimer, K., Lengsfeld, S. and Nartey-Tokoll, I.B. (1994). Determination of Major Planning Data for Solid Waste Management in Accra Metropolis , Accra Metropolitan Assembly, Waste Management Department, Accra,Ghana.

7. Tsiboe, I. A. and Marbell, E. (2004). A look at urban waste disposal Problems inAccra, Ghana.

8. World Bank (1999). Decision Makers Guide to Municipal solid waste incineration.

report group 3. pdf

Documents