Page 163 - Sustainability in the Process Industry Integration and Optimization

140 Cha p te r S i x

first level of regional resources management consists of forming
clusters of zones for biomass management. The second level involves
building the regional energy transfer cascade (RETC) and the
Regional Resources Management Composite Curve (RRMCC).
The clusters of zones formed in the first level of the methodology
are designed to minimize the environmental impact of biomass
energy exchanges among the zones within the overall supply chain
network (Lam et al., 2009). The carbon footprint (CFP) is used as a
criterion for comparing various magnitudes of this impact; cost is
another obvious criterion. The main goal of clustering is to partition
the area of the considered region into smaller subareas (the clusters)
in order to form more coherent entities. Within each cluster, stronger
and more efficient interactions and biofuel exchanges result in
minimizing the environmental impact of the whole region. Figure 6.15
presents an REC algorithm, whose steps are discussed next:

Step 1. Specify energy sources and demands based on available
system data.
Step 2. Optimize biomass exchange flows between the zones. In this

step, linear programming is used to formulate an objective
function that minimizes total CFP within the overall region.

FIGURE 6.15 Begin
Flowchart of
algorithm for
Regional Energy
Clustering. Step 1. Specification of energy sources
and demands

Step 2. Optimize biomass
exchange flows between zones

Step 3. Display the optimal
biomass exchange flows

Step 4. Cluster formation

Output: Clusters and
their properties

End