Environmental Engineering Reference
In-Depth Information
Distribution,
consumption,
and disposal
phases
Production of
raw materials
phase
Processing
phase
Air
pollutants
Raw materials from the
field
T
T
T
Water from rivers and
aquifers
Plastics from natural
gas and oil
Ingredients from
petroleum and the ground
Metals from the ground
Distribution
Consumption
Products
Processing
plant
Wastewater to
rivers and
lakes
Solid wastes
T
T
T
T
Disposal
Energy from
fossil fuels
T
Air pollutants
T
Transportation
Figure 1.5
The nonsustainable food company.
from the sun and can be grown over and over again. However, the problem with industrialized
agriculture is that it relies on the high input of energy from fossil fuels in the form of fertilizers,
herbicides, and fuel for tractors and machinery.
Extra nonsustainable elements in the production of raw materials phase are the
manufacture of plastics for packaging from petroleum and natural gas, petroleum-based
ingredients, and materials obtained from mining. Water is an issue in many parts of the
world because of shortages and the energy from fossil fuels used for its extraction, treatment
and purification.
In the processing phase, vast amounts of heat and mechanical energy are used to process the
food. All this energy comes from natural gas and electricity that is largely produced by burning
fossil fuels. Processing produces solid and liquid wastes that need treatment using energy from
fossil fuels. Products generated by the processing facility need transportation, proper storage
in warehouses, and distribution to grocery stores; and all these steps use nonrenewable energy.
Once the food products are purchased, the consumer transports the food home and
uses energy for storage and preparation. The environmental impact exerted by the
consumer may be significant depending on the product. Food products that require
extensive cooking, such as pasta and potatoes, use more energy in the household than in
processing. A study in Sweden has reported that energy expenditures during cooking
represent up to 55 percent of the total energy spent during the whole life cycle of spa-
ghetti (adapted from Foster et al., 2006). Another study on organic potatoes (also in
Sweden) has found that 16 percent of energy is spent during transportation from the
retailer to home and 29 percent in preparation (Mattsson and Wallén, 2003). Consumption
is then followed by the disposal of packaging materials and waste generated during
preparation.
