Page 72 - Solid Waste Analysis and Minimization a Systems Approach

50 BACKGROUND AND FUNDAMENTALS OF SOLID WASTE ANALYSIS AND MINIMIZATION

Raw materials

Energy Energy Energy

Production Use Disposal

Waste Waste Waste
Emissions to Emissions to Emissions to
air and water air and water air and water
Figure 2.12 Life cycle process overview.

Michigan are an attempt to close the loop by reclaiming used beverage bottles by col-
lecting a deposit at the time of purchase and refunding it at the time of recycling. The
LCA process consists of four phases

1 Goal and scope development
2 Life cycle inventory
3 Impact audits
4 Analysis and action

2.7.2 GOAL AND SCOPE DEVELOPMENT

The LCA process stems from developing environmental indices to evaluate the seri-
ousness of the by-products generated from a process and provide direction to man-
agers in deciding which by-products generate the largest threat to the environment.
The first step is to determine the specific goals and scope of study in relation to the
intended application. One key step of this phase is to specify the functional unit. The
functional unit is the measurement that will be used as the central reference point
throughout the LCA process. For the example, if a company were comparing glass
versus plastic bottles, the functional unit could be “1-L bottle container for carbonated
beverages.” The company would then rate the environmental and economic impacts
for using glass bottles versus plastic bottles. It is important to point out that the con-
tainers may not be the same weight, but provide the same functional use, in this case
containing 1 L of carbonated beverage. Apart from describing the functional unit, the
goal and scope should address the overall approach used to establish the system
boundaries. The system boundary determines which unit processes are included in the
LCA and reflects the goal of the study. Finally the goal and scope phase includes a
description of the method applied for assessing potential environmental impacts and