Environmental Engineering Reference
In-Depth Information
wind energy to supplement its process energy needs. The 250 kW wind
turbine is driven by the consistent winds off the Lake Ontario. More
recently, the same company set up a larger 850 kW wind turbine,
increasing its commitment to renewable energy.
2.5.1.3 Recovering Waste Process Energy for Reuse
Processing operations typically produce waste heat that is allowed to escape
contributing to thermal pollution. Where it is practical, the waste low-grade
heat energy might be captured for reuse.
A company (Naitove, 2012) in Southern California uses gas turbines to
generate in-house some of the electrical energy used to run its plastic
processing operation. The waste heat fromboilers wasrecovered andused
in the crystallizer/dryer unit to condition the PET resin prior to sheet
extrusion. No additional electric heating was therefore needed for the
purpose, resulting in energy as well as cost savings.
2.5.1.4 Using Only as Much Material as Is Needed to Ensure
Functionality
With plastic packaging, this translates into downgauging and avoiding
overpackaging of products. Downgauging has been a consistent trend in the
industry over the decades. The average weight of a single-use two liter PET
soda bottle, for instance, dropped from 68 gauge in the 1970s to the present
soft drink manufacturers are following suit and coming up with innovative
lighter bottles (Bauerlein, 2009).
Another example is downgauging LDPE shrink wrap material from 80 to
63 gauge, resulting in substantial material saving (Connolly, 2009).
Downgauging is possible because of improvements in materials technology
that allow less plastic to be used without sacrificing functionality of the
instance, reduced the weight of its 12 oz can from 0.048 lbs in 1970 to 0.029
lbs in 2012 without any loss in functionality.
