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8. ESTABLISHING AN EFFECTIVE ORGANIC WASTE

COLLECTION SYSTEM

Huge amounts of solid waste are produced in urban areas. Average solid waste production is
0.6 kg per person per day. A look at the composition of solid waste from cities in low- and

middle-income countries shows that readily biodegradable fractions range from 44 percent to

87 percent by weight. Levels of urbanization and modernization have a profound impact on the
production and composition of municipal waste; However, some general trends, such as high

organic matter content (50-90 percent), offer the opportunity for use through composting
processes. The waste stream is not a homogeneous mass, but a combination of different

materials (organic material, plastic, metal, textiles, etc.) that can be handled in different ways

to maximize recovery. The organic waste fraction remains the largest fraction to be recovered
[54]. Common forms of solid waste;

Solid waste: domestic and market wastes, food waste including vegetable and fruit peelings,
charcoal ash. This also includes waste from institutions and commercial centres.

Horticultural and agricultural waste: garden refuse, leaf litter, cut grass, tree prunings,

weeds, animal dung, crop residues, waste from public parks etc. Manure: poultry, pig, cow.
Agro-industrial waste: waste generated by abattoirs, breweries, processing and agro-based

industries
Sludge and bio-solid: human faecal matter from septic tanks and treatment Plants.

There are many approaches to waste management (Figure 9). Solid waste is generally managed
through landfilling, incineration, and recycling or reuse. But in developing countries, properly

designed landfills are uncommon and the cost of modern incineration is unaffordable.

Therefore, the most common method of waste disposal is some form of landfill, which includes
variants such as uncontrolled dumping in undefined areas, collection and disposal in

unmanaged open dumps, and collection/disposal in controlled landfills. It's common to find
trash collectors going door to door or lining community trash cans to collect dry recyclables.

However, these collectors are more interested in inorganic recyclable materials such as plastic

and glass but not organic waste. Agenda 21, adopted in Rio in 1992, states that environmentally
sound waste management should include safer disposal or recovery of waste and changes

towards a more sustainable model introducing integrated life cycle management concepts. It
introduced a phased approach to waste management in order of environmental priority [54].

The general principle of the waste management hierarchy (Figure 9) consists of the following

steps:

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