Promoting Resource Efficiency in Small & Medium size ... - UNEP

• Waste incineration
Incineration of waste mineralises it and reduces the volume of solid
residuals. Incineration results in the output of other waste streams
such as: air emissions, ash, slag, heat, etc. that should be treated
separately.
Types of controlled incineration processes include:
- Low-temperature (municipal) waste incinerators
- High-temperature waste incinerators
- Cement kilns
• Sanitary landfill
Sanitary landfills provide outlets for the ultimate disposal of
waste generated. A sanitary landfill is a controlled area of land on
which waste is disposed of, in accordance with standards, rules or
orders established by a regulatory body. Waste material is placed
in trenches or on land, compacted by mechanical equipment and
covered with earth and a final cover.
Within the category of sanitary landfill three technologies can be
distinguished:
- Bioactive sanitary landfills – The material is of non-mineral
quality. It is reactive and therefore needs extensive control
systems covering the operational, closure and post-closure
phase. The chemical composition of the residues is not known
(sludges from mixed waste water treatment, mixed laboratory
waste).
- Sanitary landfills for stabilsed residues – Similar to bioactive
sanitary landfills, but for materials that will not form either
gases or water-soluble substances when in contact with water,
air or other stabilised residues. The chemical composition of
the residues is well known (household residues after separating
biowaste, plastics, paper).
- Sanitary landfills for inert materials – The material is inert.
Therefore the landfill needs no control systems during the
operation phase, closure and post-closure phase (concrete).
• Open dumpsite
An open dumpsite is an uncontrolled area of land on which waste is
disposed, either legally or illegally.
• Special cases: Pre-treatment and temporary on-site
storage of waste
- Pre-treatment processes prepare waste for incineration or
landfill. For the purpose of this manual, pre-treatment does not
constitute a separate category of waste treatment technology.
Waste that undergoes external pre-treatment is dealt with under
waste incineration and landfill. If the path is not known and
documented, landfill is assumed.
- Temporary on-site storage
- Waste that is temporary stored on-site and for which the
treatment technology is not yet known constitutes a separate
category of waste treatment technology. The reporting entity
should give special attention to include adequate information
on the technology used and the processes involved in on-site
storage.
7.2 WHY:
Waste minimisation benefits for SMEs
7.2.1 Contaminated land
As early as 1996, a worldwide survey by UNEP showed that all countries
are susceptible to land contamination from a wide range of industrial
activities. Household waste increasingly contains chemical residues
from domestic cleaning and other products. It should be stressed that
because of the high cost of remediation of contaminated land, pollution
prevention programmes are a preferred strategy for waste management.
7.2.2 Waste concerns 61
Collecting, recycling, treating and disposing of increasing quantities of
solid waste and wastewater remains a major challenge for developed
and developing countries alike.
Growing landfills around the world mirror the global trends of increasing
population, prosperity and urbanisation. What is more worrying is
excessive waste generation itself: finite resources are transformed into
single-use, GHG-emitting goods that all too quickly end up in landfills.
At the same time, there is a growing realisation that waste can be a
resource too.
Overall, the waste sector contributes less than 5% of global GHG
emissions. The largest source is landfill methane (CH 4
), followed
by wastewater CH 4
and nitrous oxide (N 2
O). Nitrous Oxide (N 2
O)
contributes to climate change; a major source is human sewage and
emissions that occur during the wastewater treatment process. Methane
is also emitted during wastewater transport, sewage treatment processes
and leakages from anaerobic digestion of waste or wastewater sludge.
In addition, minor emissions of carbon dioxide (CO 2
) emerge when
waste containing fossil carbon is burnt (e.g. plastics; synthetic textiles)
and by the non-biomass portion of incinerated waste. Open burning of
waste in developing countries is a significant local source of air pollution,
constituting a health risk for nearby communities. Composting and other
biological treatments emit very small quantities of GHGs. It is worth
noting that landfill emissions continue several decades after the waste
is disposed in them, which makes it difficult to estimate emission trends.
61) UNEP, Climate Neutral Network, Waste, undated
66