Page 95 - Materials Chemistry, Second Edition

Ch002-P373623.qxd 3/22/07 5:27 PM Page 76
Sustainable Industrial Design and Waste Management
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Solid Solid
waste waste Emissions
Wood Undercoat
delivery and Carpentry Sanding, filler (polyester/ Emissions
drying and sealer nitrocellulose)

Drying of Color Drying and Emissions
Solid waste product and painting/ sanding of
sanding staining product Solid waste

Final finishing
layer-top coat Upholstery and
Emissions Polishing
(polyurethane/ packaging
nitrocellulose)

FIGURE 2.3 Waste and emissions during wood manufacturing process

Derosination is accomplished by applying a mixture of acetone and
ammonia to the surface of the wood. Spent acetone and ammonia
are the primary outputs from derosination.
• Opened pores are filled with calcium carbonate filler using a filler
knife. As filler starts to dry, it becomes tacky. Excess filler is wiped
or sanded.
• A nitrocellulose sealer is then used, followed by sanding with 200
grit sandpaper.
• Polyester pre-coat and sealing: Polyester powder dissolved in ace-
tone or turpentine in a ratio of 1 to 1 is sprayed on to the surface.
Three coatings are applied and each is followed by sanding with 220
grit sandpaper.
• Painting is performed utilizing water-based colors followed by fine
sanding. Co-solvent turpentine is used as an additive to the color.
• A wash coat of nitrocellulose is used followed by fine sanding.
• Polyurethane topcoat is sprayed to protect the upper layer.
• Polishing sebedag and oil are applied to the surface and rubbed with
cotton.

Waste and pollution generated
The furniture industry has mainly two areas with major environmental
impacts: the management of solid wood waste and the emissions from the
polyester and polyurethane spraying process.