Biomedical Engineering Reference
In-Depth Information
different reaction paths and different reactor systems and operating conditions.
Each path will have different wastes, so an environmentally friendly reaction path
integration method and reactor network synthesis method obtained by systems
engineering methods are needed to find the economic and environmental impact
of a multiobjective optimal production program [
13
].
The industrial ecosystem with a closed loop of logistics is the emphasis of
industrial ecology, which has become an important environmental policy in the
United States and Europe. Industrial ecology emphasizes the closed loop of
material to reduce the demand of the environment as a source or sink. Xerox
Corporation used this integrated approach, and their asset management plans were
involved in every aspect of manufacture, use, and handling of substances through
comprehensive methods such as reusing, remanufacturing, and recycling to close the
loop of substances. Kalundborg in Denmark, under the constraints of environmental
regulations, formed a closed loop of material flow through economic levers.
The purpose of the dematerialization of industrial products is that the investment
of resources in industrial production should be equal to the environmental capacity.
An important way to achieve dematerialization is to provide the functions or services
instead of providing the product itself. It is necessary to develop a “functional econ-
omy” to exert the maximum “usage” rather than the material goods “consumption.”
A consumer society requires shorter product life cycles. In industrial ecology, some
methods can be designed to achieve these requirements, such as the recycling of
products and upgrading technology; integrating different products, contracts, and
services supply; transferring products to other users (such as developing countries)
or returning them to the manufacturing chain; and so on, finally making products
a factor in the economy and generating benefits. The concept of remanufacturing
and circulation is different. The former refers to the extension of the production
chain, not just the material flowing in a closed loop. To achieve remanufacturing,
the economic structure should be adjusted accordingly. In general, the technological
content and added value are higher at the end of the production chain. Therefore,
the extension of the production chain should correspond to human resources and
technical level [
14
].
The energy integration of the eco-industry is to achieve effective use of energy
within the ecosystem, which not only includes the effective use of energy within
each production process, usually composed of the steam power system and heat
recovery network, but also includes energy exchange in each process. Increasing
energy efficiency and reducing energy consumption not only can save energy but
also can mean reduction of environmental pollution [
13
]. The systematic use of
energy is the most important part of industrial ecology. Energy production and
consumption are the core of industrial economy. Energy characteristics implied in
the product are not apparent as features of the product itself; the use of energy is
not in the processing and manufacturing process of products but in the process of
the use of products, such as cars, refrigerators, and air conditioners. The energy
consumption of a manufacturing process is negligible compared with the service
life.
