Microsoft Word - Environmental benefits of recycling 2010 update.doc

Forest growing

Electricity

Trees sawing

Wood product

Use

Incineration Landfill Recycling

Material production

and use

Disposal & recovery

Energy export to

the grid

Emissions from

landfill

Alternative use of

incineration

capacity

Processing

Marginal material

Ratio of virgin

material

subsitution

Co‐products

Heat/steam

Degradation rate

Avoided material

production

Post‐consumer waste

Collection

Electricity

Marginal material

Co‐products

Heat/steam

Processing to products

Figure 41 The wood system and key parameters

3.6.2 Comparison between the various end-of-life options

Recycling enables the material content to be fully exploited and thus appears as an attractive option. Recycling
for particleboard production is one of the main recycling routes for low quality recovered wood. The wood is first
shredded and reduced into chips and then agglomerated. A study entitled ‘Life Cycle Assessment for optimising
the level of separated collection in integrated MSW management systems’ (2009) conducted by Rigamonti,
Grosso and Giugliano estimated no less than 77% energy savings can be gained when producing particleboard
from wood waste instead of producing plywood from virgin material.

In the study ‘Life Cycle Assessment of wood wastes: A case study of ephemeral architecture’ (Rivela, et al.,
2006), the recycling of wood waste for particleboard manufacture is compared to the incineration of wood with
energy recovery. The results suggest that the recycling of wood waste is more favourable regarding
human health and ecosystem quality (including climate change). This can be explained by the reduction of
the environmental impact caused by forest activities (e.g. sawing and transport) since some wood or timber is
saved. However, recycling represents a larger contribution of damage to resource due to the use of
fossil fuels.

In addition, the 2006 study conducted by the US EPA about solid waste management and greenhouse gases
previously cited in the sections covering plastics, paper and food/garden waste also included a comparison of
end-of-life alternatives for dimensional lumber and medium-density fibreboard. The alternatives under study are
recycling, incineration with energy recovery and landfill. Regarding climate change, recycling is preferable
to incineration, with an improvement from incineration of 70%. Landfill appears as the worst
alternative since recycling has been estimated to perform 80% better. For energy demand the
results obtained are also in line with Rivela’s study, i.e. recycling is the most energy-consuming
option while incineration is associated with an energy credit. As a result, incineration presents an advantage of
over 150% compared to both other alternatives.