ethiopian urban setting ch4 emiission from solid waste mitigation measures

AN ASSESSMENT OF MITIGATIONOF METHANE

EMISSIONSFROMSOLID WASTE

Final Report (Part Two)

2000

March 2000 Addis Ababa

2

AN ASSESSMENT OF MITIGATION

OF

METHANE EMISSIONS

FROM

SOLID WASTE

By:

Fikru Tessema (M.Sc, B.Sc, D.Sc)

Consultant

3

TABLE OF CONTENTS

CONTENTS PAGE

Introduction 9

Background 9

Goals and objectives 10

Scope of the assessment 11

Methods 11

Target beneficiaries 11

Potential mitigation measures 12

Evaluation of mitigation measures 13

Prioritizing of mitigation measures 16

Selection of mitigation measures 16

Baseline and mitigation emission scenarios 16

Implementation strategy 18

Economic Feasibility 20

Discussion 24

Conclusion and recommendation 25

References 26

4

DEFINITION OF TERMS

Mitigation - Deliberate action to reduce the impact of climate change through

reducing the rate of accumulation of carbon in the atmosphere by

encouraging the development of carbon sinks or reducing the rate of

emissions from anthropogenic sources.

Mitigation analysis - Assessment of the impact of activities to mitigate climate

change with special emphasis on the cost of the mitigation

activities and the social and other economic costs of such

action.

Baseline - The series of activities that would follow development in the case of no

deliberate action to reduce the accumulation of carbon in the

atmosphere. Activities include economic activities and the emission of

greenhouse gases. The baseline is often illustrated as the time

progression of greenhouse gas emissions.

Baseline scenario - The sequence of activities that follow development in the

case of no deliberate action to reduce the accumulation of

greenhouse gases in the atmosphere.

Mitigation scenario - The sequence of activities that follow a development case

with deliberate action to reduce the accumulation of carbon

in the atmosphere.

Emissions inventory - The account of all sources and sinks of greenhouse gas

emitted into the atmosphere normally presented in the

format recommended by the ipcc.

Assumptions - The list of conditions that mark the environment within which an

analysis I done. This normally includes quantitative variables that

can take a range of values.

5

Base-year - The initial year for which all relevant data is available for emission

reduction costing previously preferred to be 1990 and now 1994 by

the conference of parties.

Bottom-up - Analytical technique based on the effect of the investment or project

level on the macroeconomic level.

Mitigation strategy - The plan including policy and institutional framework for

implementing greenhouse gas emission reduction options.

6

ACRONYMS:

1. S.W: solid Waste

2. CSA: Central Statistics Authority.

3. ESTC: Ethiopian Science & Technology Community.

4. NMSA: National Meteorological Service Agency.

5. NGO: Non - Government Organization.

6. IPCC: Inter Government Panel Climate.

7. GHG: Greenhouse gas.

8. SWDS: Solid Waste Disposal Site.

9. NA: Not Applicable.

10. CH4: Methane.

11. MSW: Municipal Solid Waste.

12. O&M: Operation & Maintenance.

7

EXECUTIVE SUMMARY

Methane emissions originate from several anthropogenic sources including: municipal

solid waste landfills and open dumps, wastewater treatment, domesticated livestock and

coal mining. About 65% of methane emissions from landfills come from the more

developed countries of the world, another 15% from countries with transitional

economies and 20% from developing countries.

The goal of the assessment of mitigation of methane emissions is to provide policy

makers with potential mitigation options that can both mitigate climate change and also

contribute to national and regional development objectives.

The main objectives of the mitigation assessment are also to identify, screen and

characterize technologies and practices that have potential to mitigate climate change

and contribute to the improvement of solid waste management. The output of the

assessment consists of access the decision-maker to design mitigation policies and

economic and greenhouse gas impacts of mitigation options. The analysis of mitigation

options for methane emission reduction is more aimed at identifying the solid waste

management measures that have the potential impacts on mitigating climate change

through reduction of methane emissions from landfill. Various stakeholders are potential

beneficiaries. Since mitigating climate change is a national issue, the primary users of

the mitigation assessment are likely to be decision-makers. The two approaches for

reduction of methane emissions from landfill are recovery of methane generated in the

landfill to produce energy and waste management measures to reduce quantity of

wastes go to landfill. Evaluation is done to make a rough assessment of the potential

attractiveness of options. The purpose of evaluation is to assess the impacts that the

mitigation options have on the emissions.

Various criteria were used for both evaluation and in-depth analysis of mitigation

options. Considering their potential reduction of greenhouse gas emission,

comparability with current SWM goals and priorities and potential economic,

environmental or social benefits, has prioritized the mitigation measures.

Methane emission of the Addis Ababa landfills accounts for 18% of the total emissions

of urban centers of Ethiopia and from solid waste sector accounts for 61% of the total

emissions of waste sector.

The Addis Ababa City landfill methane emission could be the focus of mitigation

measures. Because it presents the greatest opportunity in reducing greenhouse gas

8

emissions. For the purpose of methane emission mitigation analysis two different

scenarios are basically defined in this assessment. One scenario reflects a baseline

case and the other reflects the impact of mitigation options. The options like

composting, incineration and landfill gas recovery are the measures that have potentials

to mitigate methane emissions from SW of Addis Ababa City.

Table-l Analysis of Mitigation of Methane Emission from Solid Waste of Addis

Ababa City

Mitigation Methane Emissions from Solid Waste

Scenario Baseline and Mitigation Scenario

Country Ethiopia

Year 1994 - 2030

1994 2000 2010 2020 2030

BASELINE SCENARIO:

Emissions (in Gg)

4.65

9.52

12.73

16.24

19.45

MITIGATION SCENARIO:

Reduction by Composting (30% of yearly emission, in Gg)

0.00

2.86

3.82

4.87

5.84

Reduction by Incineration (45% of yearly emission, in Gg)

0.00 4.28 5.73 7.31 8.75

Reduction by gas recovery from SLF (70% of yearly emission, in Gg)

0.00 6.66 8.91 11.37 13.62

The degree of mechanization or adoption of option will depend upon economical

development, cost of labor and energy and socio-cultural attitudes of the community.

Project costs will include equipment purchase and installation, as well as operation and

maintenance (O & M) and site-specific cost. The O & M include labor costs.

Table-ll Cost of Mitigation of Methane Emission from Solid Waste of Addis Ababa City


Cost Mitigation Cost

Country Ethiopia

Year 2000

Options Total cost (US$) Cost (US$)/ton of CH4

Composting 134983 30

Incineration 666717 99

Landfill gas recovery 430052 41

vii

Composting is the most promising measure and more reliable solid waste treatment

option for Addis Ababa City because major portion is organic. Compost from such type

9

of wastes can be a good quality, consistently produced, and accepted by customers and

meeting needs of end users.

Establishing and operating incineration plants is not only for GHG emission reduction

but it can assist the solid waste management service in the improvement of collection

and transport of wastes by increasing the number of disposal sites and increasing

frequency of collection.

Sanitary landfill is an essential tool for mitigating GHG and disposing safely all types of

solid wastes. It is the only option for the disposal of the unwanted end product of other

different solid waste treatment options.

This methane emissions mitigation assessment, therefore, recommends that

composting and landfill gas recovery should be implemented since they are cost

efficient for mitigating Addis Ababa landfill methane emission. Incineration, even if its

cost is not attractive, its impact on methane emissions from solid waste is significant.

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1. INTRODUCTION

Methane is one of the principal greenhouse gases and major contributor in its

contribution to the global warming. Methane emissions originate from several

anthropogenic sources including: municipal solid waste landfills and open dumps,

wastewater treatment, domesticated livestock and coal mining. Methane is a valuable

fuel and can be collected from sources and used in one of several ways including

power generation, direct industrial, commercial and residential use (1).

Methane is emitted from landfills as the result of the anaerobic decomposition of

organic wastes. The methane migrates through the waste laterally and vertically,

eventually escaping to the atmosphere. Landfills are major global sources of methane.

About 65% of methane emissions from landfills come from the more developed

countries of the world, another 15% from countries with transitional economies and

20% from developing countries (1).

Methane emissions-reduction options for the solid waste management sector are

mainly focused on its primary sources of its emissions from landfills. Of the available

measures to mitigate and recover methane gas from its sources, collecting and

combusting the landfill gas is the primary method for reducing methane emissions

from existing landfills. Diverting organic refuse to other disposal and treatment options

and keeping refuses away from landfills can also reduce future emissions (1,2).

2. BACKGROUND

2.1 SOLID WASTE GENERATION RATE:

Quantity of waste generation units of per capita per day in Addis Ababa City was very

much unclear until 1982 when a Norconsult, a private company on waste

management, first published its findings. A Luisberger consult was also made a study

on solid waste generation rate in 1994 and 1995 (2,3).

According to the Norconsult study, the per capita generation of SW was 0.150 kg per

day. In its conclusion, the volume growth rate of the domestic solid waste generation

has an increase of 1% per year per capita based and density of 370 kg/m3 (2).

According to the 1994 study, the per capita generation of SW 0.221 kg per day per

person and density of 336 kg/m3 can be taken for planning purpose. According to the

Luisberger consult study, based on the income level, the unit of domestic waste

generation of per capita per day is 0.252 kg and density 205 kg/ m3 (3).

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According to the Norconsult study, .of the total solid waste generated in the city, 76%

is from households and the rest 5% from industries, 6% from street sweepings, 9%

from commercial areas, 1% from hospital and 3% from hotels (2).

At present, the daily total SW generation is estimated to be reach 573 tones out of

which 360 – 412 tones is collected and disposed of in landfill. The per capita based

disposal rate is also estimated to be reached 0.17 kg/capita/day. The Addis Ababa SW

generation is expected to increase to 30% by the year 2010. Wastes from households

will take the large portion due to rapid increase of population in the city (5).

2.2 COMPOSITION OF SOLID WASTE:

Domestic waste varies in composition both geographically and seasonally. The

percentage composition by weight for organic component of the solid waste of Addis

Ababa City is about 64% by weight. The combustible materials constitute 21%, the

non-combustible 3%, the organic fines 34%, the fines less than 10mm size 29% and

the recyclable materials 13% by weight (3).

2.3 LANDFILLED SOLID WASTE:

The amount of refuse that already disposed of in to landfill is estimated to be more

than 6.6 million cubic meters or 2.4 million tones it is under operation for the last 35

years back. The landfill operational procedure is unsanitary. It is simply spreading and

leveling by using the two bulldozers and compacting by one steel studded wheel type

of compactor. The already disposed solid waste to the landfill in the last 10 years has

a yearly increment of 5.4% (4).

3. GOAL AND OBJECTIVES

3.1 GOAL:

The goal of this mitigation assessment is to provide policy makers with an

evaluation of mitigation options that can both mitigate climate change and also

contribute to national and regional development objectives.

3.2 OBJECTIVES:

The main objectives of this mitigation assessment are to identify, screen and

characterize technologies and practices that have potential to mitigate climate

change and contribute to the improvement of solid waste management.

12

3.3 OUTPUTS:

The output of this assessment consists of:

Access the decision-maker to design mitigation policies.

Economic and greenhouse gas impacts of mitigation options.

4. SCOPE OF THE MITIGATION ASSESSMENT OF METHANE EMISSIONS

This mitigation assessment is mainly focused on identifying potential mitigation

measures and their impacts on the Addis Ababa landfill methane emission and

developing methane emissions mitigation strategy.

5. METHODS

This mitigation study has been conducted for the year 2000 to assess mitigation

measures for methane emissions in the solid waste sector. This assessment is a

bottom-up approach for the analysis of mitigation options. Because it is carried out at

regional level, i.e. for the Addis Ababa City landfill methane emission reduction. It is

more aimed at identifying the solid waste management measures that have the

capacity and potential impacts to mitigate climate change through reduction of

methane emissions from landfill.

A data needed for the assessment of mitigation measures of the Addis Ababa City

landfill emissions has been collected from Health Bureau, CSA, ESTC and NMSA.

The compiled data has been analyzed using the IPCC guidance for mitigation

assessment. The figure analysis and cross tabulations have been done using the

computer.

6. TARGET BENEFICIARIES

Various stakeholders are potential beneficiaries. The primary users of the

assessment are likely to be decision-makers of the City Council. The benefits

obtained from the assessment are to satisfy the needs of policy makers who are

responsible for evaluating and designing mitigation measures.

The scientific community, NGOs, interested groups and regional and national

government organizations are likely to benefit from access to the output of this

assessment.

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7. POTENTIAL MEASURES FOR MITIGATION OF METHANE EMISSIONS

There are two approaches for reduction of methane emissions from landfill:

1. Recovery of methane generated in the landfill to produce energy

2. Waste management measures to reduce quantity of wastes go to landfill.

LANDFILLS METHANE RECOVERY:

The atmospheric emissions are gases from solid waste placed in the landfills. A

number of technologies are in use in several countries, both in developed and

developing countries to control landfill atmospheric emissions. The landfill gas can

be extracted through a series of wells drilled into the refuse placed in the landfill.

The recovered methane can be used to generate electricity. The waste heat

produced during electrical generation can also be recovered and used for local

heating needs. Electricity generation requires relatively large amounts of landfill gas

and is therefore suitable for larger landfills and economic benefits depend upon the

price at which the electricity can be sold (1).

ALTERNATIVE WASTE MANAGEMENT MEASURES:

The other technical alternative waste management practices applicable in the near

and longer term are reducing wastes go to the landfill. Minimizing waste go to the

landfill can also improve landfill management and operational costs for waste

management.

The potential alternative waste management and mitigation measures are:

1. Source reduction of solid waste

2. Composting of solid waste

3. Recycling of solid waste

4. Incineration of solid waste

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8. EVALUATION OF MITIGATION OPTIONS FOR METHANE EMISSIONS

Evaluation is done to make a rough assessment of the potential attractiveness of

options. The purpose of evaluation is to assess the impacts that the mitigation

options have on the emissions. Various criteria were used for both evaluation and

in-depth analysis of mitigation options.

Since for some options to quantify its impact on the GHG emissions is difficult,

simple assumptions have been made to roughly estimate its GHG impacts (Table-I).

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Table-I Evaluation of Implication of Mitigation Options on Methane Emissions from Municipal Solid Waste,

Addis Ababa, 2000

Mitigation Methane Emissions from SWDSs

Mitigation Mitigation Options

Country Ethiopia, Addis Ababa

Year 2000

Criteria

Score

(0:Low)

Mitigation Options

Waste source

Reduction

Waste

Recycling

Waste

Composting

Waste

Incineration

Sanitary

Landfill

Potential for large impact on GHGs 0-40 20 15 40 40 30

Direct cost/benefit ratio of the option 0-40 30 20 35 15 30

Indirect economic impacts:

Increase in job opportunity

Decrease in import payments

0-15

0-10

NA

10

15

10

15

10

15

10

15

10

Consistency with national environmental goals:

Reducing emissions of air pollutants

Effectiveness in limiting other environmental

impacts

0-15

0-20

NA

20

NA

10

5

10

5

10

5

10

Potential ease of implementation 0-25 10 20 20 10 10

Long-term sustainability of option 0-25 10 20 25 25 25

Consistency with national development goals 0-15 15 15 15 10 10

Data availability for evaluation: Technology characterization

0-10

NA

10

10

10

10

Contribution to improve waste management system

0-20

20

10

15

15

15

Total 240 135(67%) 145(64%) 200(83%) 165(69%) 170(71%)

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SOURCE REDUCTION:

According to the overall evaluation result, it can be concluded that minimizing the

amount of solid waste goes to the landfill can mitigate the methane emissions (4). It

can reduce the landfilling of solid wastes through minimizing its generation. Of the

total waste generated in Addis Ababa City, 76% is from households. Source

reduction can be applicable through improving the wasteful life-style of the

population through encouraging and raising awareness of the population to use

reusable materials instead of using disposable materials (1,9).

RECYCLING:

According to the overall evaluation result, it can be concluded that this option may

not have significant impact on GHGs emissions because of low portion of

biodegradable and recyclable materials. The percentage composition by weight for

recyclable materials (paper, rubber, wood, bone, plastics, textiles, metals and

glasses) for Addis Ababa solid waste is 13% by weight. But organizing waste

recyclers to maximize their efficiency may help to limit waste go to the landfill that

will have an impact on landfill methane emissions in the future.

COMPOSTING:

According to the overall evaluation result, it can be concluded that this option is

found to be a feasible option to mitigate methane emissions because of that the

organic component constitute high portion that can be degraded aerobically to

compost (1). The percentage composition for organic component of the solid

waste of Addis Ababa City is about 64% by weight.

INCINERATION:

According to the overall evaluation result, it can be concluded that this option has

high impact on methane emissions from SW. Incineration is a combustion process

by which solid wastes are reduced primarily to ash and other gases. Often energy

recovery is applied. The feasibility of combustion process is dependent on the

nature of wastes and cost of incineration plants. The combustible portion of the

Addis Ababa Solid Waste constitutes 21% by weight. A waste with high organic

content, it is not suitable for mass incineration. As a result, the incineration plant

needs high capital and operating and maintenance costs.

17

SANITARY LANDFILL WITH GAS RECOVERY:

According to the overall evaluation result, it can be concluded that this option is

found to be feasible in case of Addis Ababa City that the recovered gas can be used

for producing electricity and heating and cooling effect (1). Principally, gas is

generated from MSW placed in landfills. Methane also constitutes 50% of the total

gas generated from landfill with density of 0.718 kg/m3 (12).

9. PRIORITIZING OF MITIGATION MEASURES OF METHANE EMISSIONS

The Addis Ababa City landfill methane emission accounts on the average about

18% of the total emissions of urban centers of Ethiopia. Thus, the Addis Ababa City

landfill methane emission could be the focus of mitigation measures. Because it

presents the greatest opportunity in reducing greenhouse gas emissions.

The mitigation measures have been prioritized by considering their potential

reduction of greenhouse gas emission, comparability with current solid waste

management goals and priorities and potential economic, environmental or social

benefits. Some GHG mitigation measures can also be integrated with other current

waste management projects (6).

10. SELECTION OF MITIGATION MEASURES OF METHANE EMISSIONS

The potential mitigation measures that are feasible to mitigate methane emissions

from solid waste are composting, incineration of solid waste with energy recovery

and sanitary landfill with gas recovery.

11. BASELINE AND MITIGATION- EMISSION SCENARIOS

For the purpose of methane emission mitigation analysis two different scenarios are

basically defined in this assessment. One scenario reflects a baseline case and the

other reflects the impact of mitigation options.

18

11.1 BASELINE SCENARIO:

A baseline/reference scenario is a projection of GHG of a country as if no

policies are out in place designed to reduce GHG emissions. There is not

landfill methane emissions recovery practice in urban centers of Ethiopia. A

GHG emissions projection for Addis Ababa City has been done to illustrate

methane emissions from landfill for each year 1994 – 2030, 1994 as a base-

year for emissions inventory (Table-II).

11.2 MITIGATION-EMISSION SCENARIO:

A mitigation scenario reflects a future in which climate-change mitigation is a

primary objective for adoption of technologies and practices that reduce GHG

emissions by limiting wastes go to the landfill for Addis Ababa City. A

compost plant that has a capacity to treat 200 tons of wastes per day can

reduce 30% of the yearly total methane generation from SW. An incineration

plant with a capacity of treating 300 ton of solid waste per day can reduce

methane emissions estimated at 45% of the yearly total generation from SW.

The methane generated from landfills can typically be recovered at 70% of

the yearly total methane gas emissions. The impacts of these different options

on methane emissions are given in (Table-III).

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12. IMPLEMENTATION STRATEGY

The strategic plans for the solid waste management should aim at progressive

improvements of the existing environmental pollution in the city and gradually to

meet the standard requirements for safe handling and disposal methods, which will

help to achieve environmental effectiveness in general and mitigating methane

emissions from solid waste in particular. To this end, the following strategic plans

have been drawn:

12.1 GENERAL STRATEGIC PLANS WITHIN THE SOLID WASTE SECTOR:

12.1.1 Enhancing the present onsite handling capacity:

12.1.1.2 Reduce the miss-handling and uncontrolled disposal of wastes

and using use-and-throw materials at residential and working

areas.

12.1.1.3 Educate and encourage the population to use reusable materials

and transport and empty their wastes to the transfer stations

properly.

12.1.1.4 Enforce regulatory actions on practices of the population affecting

the environment by miss-handling of its by–product as solid

waste.

12.1.2 Enhancing the present solid waste collection and transport capacity:

12.1.2.1 Increase the solid waste collection capacity through securing

additional waste collection trucks and introducing incentives for

the collection crew.

12.1.2.2 Introduce additional transfer stations possibly at accessible points

in the residential, institutional and commercial sites.

12.1.3 Improving the present solid waste disposal and treatment method:

12.1.3.1 Close the existing landfill.

12.1.3.2 Construct new sanitary landfill.

12.1.3.3 Introduce composting and incineration of solid waste with energy

recovery.

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12.2 SPECIFIC STRATEGIC PLANS FOR METHANE EMISSION MITIGATION

OPTIONS:

12.2.1 Develop Composting of Solid Waste:

Municipal solid waste to compost is possible by use of compost technology.

This technology is a valuable tool already being used to increase

environmental effectiveness.

12.2.2 Develop Incineration of Solid Waste with Energy Recovery:

Municipal solid waste can be processed by use of incineration technology.

Atmospheric emissions in case of incineration of refuse produces a flue gas

that contains different components free of methane gas. Quality of incineration

plants emissions into the atmosphere determines the efficiency of the

technology. It is expected to be within the emission-limits for incinerators.

12.2.3 Develop sanitary landfill with gas recovery:

A sanitary landfill with gas recovery project can be considered with a rough

estimate of the current and potential future amount of gas that can be

produced. This rough approximation method only requires knowledge of how

much waste is in place at the target landfill. The waste tonnage should ideally

be less than 10 years old.

The Addis Ababa landfill is in use for the last 35 years back and designed to

handle 91400 tones of waste disposed of annually by the city’s 2.6 million

inhabitants. The already landfilled refuse is estimated to be more than 6.6

million cubic meters or 2.4 million tones (4).

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12.3 IMPLEMENTATION BARRIERS

Barriers Possible Solutions

Lack of attractiveness of waste-to-energy and waste-to-compost

Aware policy makers on economic and environmental benefits of waste-to-energy and waste-to-compost. Adopt tax incentives

Lack of awareness on the part of government and others with methane recovery and source reduction techniques

Provide information through workshops to potential project developers and lending agencies regarding the role waste management projects can play in meeting country goals

Lack of access to technologies such as landfill gas recovery, composting and incinerator

Encourage joint ventures and the introduction of new technologies

Lack of capital investment Raise awareness on profitability of solid waste projects with development agencies

13. ECONOMIC FEASIBILITY OF THE PROJECT OPTIONS:

The purpose of evaluating the economic feasibility of the project options is to

ensure that the project meets a target level of cost effectiveness. There may be

several goals of a gas recovery project: profitability, energy & fertilizer supply, or

emissions reductions (or a combination of all).

The economics of such a project will be evaluated in terms of the cost of

emissions avoided. A threshold level of cost effectiveness may be set at US$ 50

per ton of methane emissions avoided. GHG recovery/reduction from MSW might

be considered a necessary environmental control operation. In such cases, costs

associated with gas recovery would be a necessary expense, whether gas

utilization is considered or not (10).

13.1 Cost Analysis:

The degree of mechanization to be adopted will depend upon economical

development, cost of labor and energy and socio-cultural attitudes of the

community. Project costs will include equipment purchase and installation, as well

as operation and maintenance (O & M) and site-specific cost. The O & M include

labor costs (10).

22

13.1.1 Cost of Compost Technology:

Plant Capacity: treat 100 - 200 ton of SW per day

Cost Breakdown:


Mitigation Cost of Mitigation Options


Year 2000

Component Total Cost (US$)

Plant cost 107987

Operating and maintenance (O&M)

cost 10% of capital cost

10798

Construction cost 15% of capital

cost

16198

Total 134983

Benefits:

Soil conditioning compost production

Reduce import cost for fertilizer

Improve solid waste final disposal

Job opportunities

GHG emissions avoided

Enhancing carbon sinks

23

13.2 Cost of Incineration plants:

Plant Capacity: treat 100 - 300 ton of SW per day

Electric power generation: minimum 40 000 kW per day

Cost Breakdown:




Year 2000

Component Total Cost (US$)

Plant cost 533374

Operating and maintenance cost

10% of equipment cost

53337


cost

80006

Total 666717

Benefits:

Revenue from the gas recovery

Energy supplied and reduce energy cost

Emissions reductions

Job opportunities

Odor control


24

13.3 Cost of Landfill Gas Recovery:

Plant Capacity: recover 70% of total methane emitted per day

Cost Breakdown:




Year 2000

Component Total Cost (mill. US$)

Plant cost 344042

Operating and maintenance cost

10% of capital cost

34404


cost

51606

Total 430052

Benefits:

Revenue from the gas recovery

Energy supplied and reduce energy cost

Emissions reductions

Job opportunities

Odor control


25

25

14. DISCUSSION

There are different beneficial uses of compost including GHG emissions reduction

from SW, bio-remediation and pollution prevention, disease control for plants and

animals, erosion control and landscaping, composting of contaminated soils,

reforestation, wetland restoration and habitat revitalization.

The cost of compost technology is dependent on a number of factors: plant

capacity and cost recovery system. The cost recovered from the sale of compost

is also determined by its quality, consistency of product quality, customer

acceptance, and distance from supplier to customer and meeting needs of end

users. Compost quality and consistency of quality over time lead to customer

acceptance and continuing sales. The distance from the supplier to the customer

impacts the marketing of compost. Since compost is marketed at a comparatively

low value, the transportation cost may have a larger impact on compost than most

other recovered products.

The amount of solid waste intake per day per hour of the incineration plant varies

in accordance with the power of the required technology and the amount of

methane emission reduction. This plant can be planted in different zones, woredas

or kebeles where the waste is located or disposed.

The cost of incinerators is dependant on the efficiency of the technology which

enables not to pollute environment during the waste treatment process, to treat

every type of waste and to obtain from the process of waste treatment a

considerable amount of complementary products. Mass incineration of solid waste

is an approach to spare landfills space and minimizes transportation costs. The

main problem with mass incineration is that it is not a promising action because of

very large costs for facility construction and operation, unresolved issues of

harmful air emissions and control device adequacy and reliability, and concern

about ash toxicity and safe long-term disposal. Moreover, mass incineration

conflicts with the alternatives of recycling and composting.

The cost of sanitary landfill is dependent on the complexity of the technology

and cost recovered from the sale of gas recovered. It incurs costs for gas recovery

and a minimum amount for gas cleaning to remove moisture and impurities (12).

26

26

15. CONCLUSION AND RECOMMENDATIONS:

The compost facility and the potential end users that are located within a

marketable distance may limit the markets available to a compost operation.

Incineration technology requires high capital for investment, which may not be

seen as an attractive. But, the installation of such a plant would definitely be

instrumental in reorganizing the transformation of urban waste in to economic

value.

Regarding the recovered landfill gas, it can be used for onsite electricity

generation or for residential and institutional uses.

Composting is the most promising measure and more reliable solid waste

treatment option to mitigate methane and improve solid waste management

system for Addis Ababa City because the major portion is organic. Compost from

such type of wastes can be a good quality, consistently produced, and accepted

by customers and meeting needs of end users.

Establishing and operating incineration plants is not only for GHG emission

reduction but it can assist the solid waste management service in the improvement

of collection and transport of wastes by increasing the number of solid waste

treatment options.

Sanitary landfill is an essential tool for mitigating GHG and disposing safely all

types of solid wastes. It is the only option for the disposal of the unwanted end

product of other different solid waste treatment options.

27

27

15. REFERENCES:

1. H. Glas, etal, Solid Waste Disposal, Netherlands, 1994

2. Nor consult, Addis Ababa Solid Waste Management Study, 1982.

3. Gordon, S, Addis Ababa Solid Waste Management 3rd and 4th Study, 1994 &

1995.

4. Region 14 Health Bureau, Annual Activities Reports, Addis Ababa, 1984-1998.

5. Health Bureau, Addis Ababa, Health Sector Development Program, A5 Year

Plan (1998-2002), Addis Ababa, May 1998.

6. USEPA, Safer Disposal for Solid Waste, EPA/530-SW-91-092, 1993.

7. USEPA, Let us Reduce and Recycle: Curriculum for Solid Waste Awareness,

EPA/530-SW-90-005, 1990.

8. NMSA, A 1999 Greenhouse Gases Inventory Report, 1999.

9. USEPA, Waste Reduction Activities of Selected Waste-Wise Partners, SWER

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10. USEPA, A Guide for Methane Mitigation Projects, Jan. 1996.

ethiopian urban setting ch4 emiission from solid waste mitigation measures

Environment