Life cycle assessment, material design

Early design assessments similar to those presented in previous sections of this chapter have the following limitations (1) they tend to focus on the reaction step and neglect the impacts of downstream units, (2) the assessment includes one or a small number of environmental indicators, and (3) the early assessment typically does not consider impacts beyond the process boundary, for example, the environmental burdens associated with the life cycle of materials used in the process. In this section we will explore some approaches to address these limitations. 

Typical life-cycle assessments are conducted during the product review stage of a process, after the plant, prototypes, and detailed designs of the product have been performed. However, Mueller et al.111 state that life-cycle evaluation should be conducted starting at the planning stage of product development. They illustrate this using an example of multifunctional chip cards that are used in a wide variety of electronics. They determine the amount of material used... 

In the near future, the main concerns of CAPE will probably focus on issues related to product design (molecular modeling for solving function-property-composition problems), supply chain management (cost reduction of raw materials, effective use of energy and its new sources), and life cycle assessment (mitigation of climate change, process sustainability). 

Life-cycle assessment (LCA) is a three-step design evaluation methodology composed of inventory profile, environmental impact assessment, and improvement analysis (Keoleian and Menerey 1994). The purpose of the inventory step is to examine the resources consumed and wastes generated at all stages of the product life cycle, including raw materials acquisition, manufacturing, distribution, use, repair, reclamation, and waste disposal. 

Since life cycle assessment (LCA) can be more than an environmental impact assessment approach, chapter Life Cycle Sustainabiftty Assessment A Holistic Evaluation of Social, Economic, and Environmental Impacts discusses life cycle sustainabiftty assessment. This extends the holistic environmental LCA to account for the economic and social pillars of sustainabiftty. Lastly, chapter Embedding Sustainabiftty in Product and Process Development—The Role of Process Systems Engineers describes the practical role of process systems engineers in the implementation of sustainabiftty in product and process development. It shows some key aspects and tools that practitioners should take into account to design and develop more sustainable products and processes during material selection, process design, process and product modeling, and supply chain implications. 

Figure 13.6 Life cycle of polyfmethyl methacrylate) (PMMA)-containing products. MMA, Methyl methacrylate ACH, acetone cyanohydrin method TBA-DO, tertiary butyl alcohol (isobutylene) direct oxidation method TBA-DOE, tertiary butyl alcohol (isobutylene) direct oxidative esterification method C2, ethylene method TR, thermal recovery MR, material recycling. Modified from Kikuchi Y, Hirao M, Ookubo T Sasaki A. Design of recycling system for polyfmethyl methacrylate) (PMMA). Part 1 recycling scenario analysis. Int J Life Cycle Assess 20i4 i9(i) 120—9.

Life cycle assessment (LCA) is defined in Horne [4] as the compilation and evaluation of inputs and outputs and the potential impacts of a product system throughout its life cycle. In E-LCA, all input materials, waste, and emissions are accounted for at all stages raw material extraction and processing product and/or service manufacturing use and disposal and finally transportation. The comprehensive data requirement of LCA makes it a particularly effective mechanism for systematic assessment of environmental impacts when designing chemical engineerir processes to produce chemicals, fuels, and other product systems [4]. 

Process design engineers should be concerned not only about the enviroiunental impacts that are directly generated in the designed process, but also consider the environmental impacts that are associated with the provision of the raw materials and services they specify as inputs to their processes. In recent years, Life Cycle Assessment (LCA) has been given a lot of attention as an environmental indicator of chemical processes [24], LCA is a comprehensive technique that covers both upstream and downstream effects of the activity or product under examination, thus often being referred to as cradle-to-grave analysis [25]. 

Figure 3. Material design principles for the environment Life Cycle Assessment...

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