Abstract:
Solid waste should be characterized by their sources, types of wastes produced, as well as
generation rates and composition. Accurate information in these characteristics is necessary to
establish proper waste management systems and for regulatory, financial, and institutional
decisions making. The lack of timely information about the generation and composition of solid
waste in Addis Ababa is one of the reasons among many for unsatisfactory solid waste
management in Addis Ababa.
This research was conducted in Arada Sub City, Addis Ababa, Ethiopia to determine the
commercial solid waste, domestic and commercial solid waste generation rates and their
physical and chemical composition in order to contribute to decision support in planning and
development of municipal solid waste management systems.
The study was carried out by classifying the whole commercial establishments population in
Arada Sub City in two five strata. Commercial solid waste generation and composition data were
collected and solid waste management related survey was also conducted. The collected data was
analyzed using Statistical Package for Social Science 10 (SPSS 10) software. Hand sorting was
used for classifying the collected waste in to the following fourteen fractions: Paper, Plastic,
Glass, Metal, Food waste, Textiles/leather, Rubber, Wood, Yard waste, Inorganic, Electronics,
Potentially hazardous Waste, Special waste, and particles less than 10mm. Proximate, ultimate
and calorific value were also determined in selected commercial solid waste fractions such as
food waste, yard waste, paper and textile.
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The study result shows that in Arada Sub City the estimated commercial solid waste generation
rate per employee per day is 1.6 Kg and 4.9 lt by weight and volume respectively. And the
average commercial solid waste density is 323.4 Kg/m3. Total commercial and residential solid
waste generation rate per capita per day by weight and by volume in Arada Sub City is 0.55 Kg
and 1.97 lt, respectively. And the density of commercial and residential solid waste is 277.7 Kg
/m3.
The percentage composition of commercial solid waste fractions clearly shows that food waste
takes the largest proportion of commercial solid waste and followed by paper, yard and plastic
waste consecutively, by weight and volume. This study also indicates the presence of potentially
hazardous waste in the studied area i.e. 0.36 % by weight and 0.2 % by volume from the total
commercial solid waste generated per day.
The result shows that due to inadequate solid waste management system, Arada Sub City has
faced a problem related to solid waste collection and disposal. The existing infrastructure for
solid waste collection in Arada Sub City is not proportional to the amount of solid waste
generated from commercial and residential source. In addition the number of municipal
containers and trucks for collection and transportation of waste is not adequate.
If composting and recycling are exercised in Arada sub city there is a possibility to reduce the
amount of commercial solid waste going to be disposed in the landfill from Arada Sub City by
98.04 %. The energy value of food waste, yard waste, paper and cardboard from commercial
source is higher than their respective energy value from residential source. The C: N ratio of the
waste is also suitable for compost making.
Thus based on the generation rate and composition of solid wastes in Arada Sub City integrated
solid waste management system which combines a range of solid waste treatment options like
source reduction, composting, recycling and waste to energy transformation is recommended.