Page 101 - Materials Chemistry, Second Edition

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Sustainable Industrial Design and Waste Management
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Saw dust and wood flour:
• Used as a fuel by converting them into briquettes.
• Used in particle board or MDF manufacturing.
• Added to flooring tiles to give thermal and resilient properties.

General precautions:

• Burning treated or coated wood can release regulated hazardous air
pollutants.
• Waste streams should not be combined (i.e. mixing wood with glue
and sawdust from rough mills) as it may inhibit optimal secondary use.

Cost/benefit analysis
Solid waste
• The estimated amount of wood input material loss in any factory is
about 20–30%.
• By applying the above recommendations by the workshop/factory
and recycling the wood waste or selling it at a suitable price as raw
material to other industries; will reduce the loss percentage (5–10%),
as well as bring a return for the furniture workshop/factory owner.
• By simple calculations the economic savings can be predicted for
beech wood as an example:
3
– 1m beech ranges between $316 and $333.
3
– Economic loss 0.25 325 $81.25/m .
– By adapting cleaner production opportunities 81.25 (.07 325)
3
$58.5 is saved per m , and this is without adding the return from
recycling that will certainly cover the initial cost of the wood raw
material.
– Economic savings 72% (not including recycling return).

Spraying chemicals
• Raw material substitution or elimination is the replacement of exist-
ing raw materials with other materials that produce less waste, or act
as a non-toxic waste.
– Using high-solids coatings: Traditional sealers and topcoats are 20%
solids or less, meaning that 80% or more of the coating evapor-
ates and is wasted even if the transfer efficiency (TE) was 100%.
– Replacing thermoset surface coatings with thermoplastic.
• Process or equipment modification is recommended in order to reduce
the amount of waste/pollution generated, for example:
– Manufacturers can change to a paint application technique that is
more efficient than conventional spray guns, for example, high-
volume/low-pressure (HVLP) guns. HVLP guns provide transfer
efficiency (TE) as high as 40 to 65% compared to 20 to 40% for