Page 128 - Sustainability in the Process Industry Integration and Optimization

CHAPTER 5

Mass Integration

he two main branches of Process Integration are energy
integration and mass integration. Mass integration is a
Tsystematic methodology that provides a fundamental
understanding of the global flow of mass within the process and
then employs this understanding to identify performance targets
and to optimize the allocation, separation, and generation of streams
and species. In the context of wastewater minimization, a mass
integration problem involves transferring mass (contaminant load)
from rich process streams to lean process streams in order to achieve
their target outlet concentration and simultaneously minimizing
waste generation and the consumption of utilities—including
freshwater and external mass separating agents (Rašković, 2006).

5.1 Water Integration
Water is widely used in various industries as an important raw
material. It is also frequently used in the heating and cooling utility
systems (e.g., steam production, cooling water) and as a mass
separating agent for various mass transfer operations (e.g., washing,
extraction). Strict requirements for product quality and associated
safety issues in manufacturing contribute to large amounts of
high-quality water being consumed by the industry. Stringent
environmental regulations coupled with a growing human population
that seeks improved quality of life have led to increased demand for
quality water. These developments have increased the need for
improved water management and wastewater minimization.
Adopting techniques to minimize water usage can effectively reduce
both the demand for freshwater and the amount of effluents generated
by the industry. In addition to this environmental benefit, efficient
water management reduces the costs for acquiring freshwater and
treating effluents.
A number of different methodologies have been applied to
minimizing water use and effluents. These include

• Minimizing water consumption through efficient management
and control of process operations

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