Life cycle, definition

Life cycle assessment is defined by ISO 14040 as compilation and evalu ation of inputs, outputs and the potential environmental impacts of a product system throughout its life cycle. The ISO standards regulate the procedural aspects of LCA. They do not, however, provide all the information required for carrying out an LCA study. The main phases of LCA are goal and scope definition, inventory, impact assessment, and interpretation. The various applications of LCA are not regulated by the standard (Fig. 15.1). 

ISO, F.nvironmental Management—Life Cycle Assessment—Goal and Scope Definition and Inventory Analysis (ISO 14041). 

The analysis of accidents and disasters in real systems makes it clear that it is not sufficient to consider error and its effects purely from the perspective of individual human failures. Major accidents are almost always the result of multiple errors or combinations of single errors with preexisting vulnerable conditions (Wagenaar et al., 1990). Another perspective from which to define errors is in terms of when in the system life cycle they occur. In the following discussion of the definitions of human error, the initial focus will be from the engineering and the accident analysis perspective. More detailed consideration of the definitions of error will be deferred to later sections in this chapter where the various error models will be described in detail (see Sections 5 and 6). 

Life Cycle Interpretation. The results obtained within the Life Cycle Inventory and/or the Life Cycle Impact Assessment are interpreted in the light of the Goal and Scope Definition (e.g., by means of sensitivity or uncertainty analyses) in order to draw conclusions and make recommendations. ... 

ISO 14041 1998 (1998) Environmental Management - Life Cycle Assessment - Goal and Scope Definition and Life Cycle Inventory Analysis. European Commitee for Standardisation, Brussels, Belgium. 

The inventory results should be presented in clear form, how much and what substances from the environment enter the system and how much get out. These results serve for subsequent life cycle impact assessment [48], The aim of the life cycle impact assessment is to measurably compare the environmental impacts of product systems and to compare their severity with new quantifiable variables identified as impact category. The impact categories are areas of specific environmental problems such as global warming, climate changes, acidification, eutrophication, ecotoxicity and others. Already in the phase of definition of the LCA study scope, it is necessary to describe what impact category will be applied and which of their environmental mechanisms will serve as a basis for impact assessment [46],... 

Rebitzer G, Ekvall T, Frischknecht R, Hunkeler D, Norris G, Rydberg T, Schmidt WP, Suh S, Weidema BP, Pennington DW. Life Cycle Assessment Part 1 Framework, Goal and Scope Definition, Inventory Analysis, and Applications. Environment International. 2004 30(5) 701-720. DOI 10.1016/j.envint.2003.11.005... 

Life cycle presents a typical allocation case because the refining process is a multiple product process and the other sub-products obtained during diesel production are shown in Figure 2, together with the definition of the most important processes involved in the refining step. 

ISO (1998) ISO 14041 Environmental management - Life cycle assessment - Goal and scope definition and inventory analysis. International Organisation for Standardisation, Geneva... 

In the forthcoming Hazop standard (IEC 61882, 1999) the Hazop studies are recommended to be carried out throughout the life cycle of a system. But for the concept and definition phase of a system s life cycle other basic methods are suggested (see Fig. 3). 

We start with a definition of the problem and based on this, we identify the candidates (such as, molecules, mixtures and formulations) through expert knowledge, database search, model-based search, or a combination of all. The next step is to perform experiments and/or model-based simulations (of product behavior) to identify a feasible set of candidates. At this stage, issues related to process design are introduced and a process-product match is obtained. The final test is related to product quality and performance verification. Other features, such as life cycle assessment could also be introduced at this stage. 

System qualification is a process that ensures that an analyzer system is installed and operated according to requirements that are aligned with the intended use of the system. The commonly used approach in the pharmaceutical industry is the system life cycle or SLC process. In the SLC approach, the definition of intended use, design, configuration, installation and operation is linked and documented over the lifetime of a system. 

Many site-specific characteristics have an impact on vitrification technologies. One critical aspect of any thermal technology is the water content of the waste. Water dilutes feed material, requires energy to drive off, and physically limits the feed rate of waste. Feed preparation is another variable, which differs with the technology and with site-specific characteristics. Many estimates do not take into account site preparation and waste disposal costs. Only complete treatment life-cycle assessments can provide reliable comparison data, and such studies are, by definition, highly site and waste specific (D18248T, p. 55). 

Life-cycle goal definition The reason(s) for undertaking die individual assessments in die LCA. 

Life-cycle goal definition How well does the solvent work ... 

The core of LCA is a cradle-to-grave life-cycle inventory analysis that is fundamentally an engineering exercise describing a chemical, material, and energy accounting balance for the entire product system. The various inputs and outputs are collected or inventoried for each unit operation in the defined system (see fig. 4.4). A key qualifier in the figure is the definition of the system boundary, as it will directly affect the quality of the final results and conclusions. The inventory practice and methods are relatively well defined. 

In the environmental policy life cycle, four phases can be discerned 1, calling attention to the problem 2, definition phase 3, formulation of the solution and taking measures and 4, control phase. The development of concentration techniques with an interface and control function is indispensable in phases 1, 2, and 4. This situation is illustrated in Figure 2. 

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