Biomedical Engineering Reference
In-Depth Information
(4) Multilevel life cycle assessment and structural optimization of product
At present, LCA has been used for the environmental management of product or
processes and has achieved good results. First, the product life cycle multifaceted
product evaluation model is divided into five stages: access to raw materials,
production process, distribution process, utilization process, and recycling. Within
each stage, there are multiple evaluation indicators for each factor; finally, using the
method of a multi-index to synthesize these indicators, you can obtain the economic
indicators, total environmental indicators, total social indicators, and composite
indicator.
11.4.3.2
Energy Integration Analysis Methods
The energy integration analysis methods mainly include the integrated pinch
analysis of all the energy, top-level analysis of the whole-process transformation,
and a mathematical programming method for whole-energy integration and the
three-link model method [
172
].
(1) Integrated pinch analysis of whole energy
The whole composite curves based on the whole-temperature enthalpy curve pro-
vide whole-fuel and power consumption optimization objectives. Whole composite
curves visually reflect the heat transfer conditions between craft process and public
works. The whole composite curves can visually analyze the amount of energy
recovery, energy conversion, and utility consumption.
(2) Integrated mathematical programming methods for whole energy
A whole-energy integration method using pinch point analysis to find the amount of
heat recovery of the transformation process, the consumption of public works, pos-
sible solutions for the power turbine network, and a whole-process energy-saving
program and then establishing an energy integration subsystem superstructure and
mixed integer nonlinear programming (MINLP) model and finally using mixed
sets of continuous evolutionary algorithms for solving the optimal or near-optimal
energy integration program.
The advantage of mathematical programming method when searching for the
optimal process and operation conditions of energy system is that the strict optimal
solution could be obtained under given conditions.
(3) Whole-energy integration of the three-link model method
Assumptions
①
The main forms of energy in the process are heat, flow work and steam, which
are converted via conversion equipments such as stove and pump.
②
Except for the part that is converted into products, energy in the forms of heat,
work and steam enters the energy recycle system after it passes into the core link
of technology and pushes the completion of technology process along with the
recycling energy.
