The analyze of the life cycle for a pneumatic connector.
Life Cycle Assessment (LCA) is a tool for the systematic evaluation of the environmental aspects of a product or service system through all stages of its life cycle, "from cradle to grave". LCA provides an adequate instrument for environmental decision support. The International Organization for Standardization (ISO) has standardized this framework within the ISO 14040.
2. LCA FOR THE EVALUATION OF THE
PRODUCT ENVIRONMENTAL IMPACT
A product's life cycle starts when raw materials are extracted from the earth, followed by manufacturing, transport and use, and ends with waste management including recycling and final disposal (SETAC, 1993). At every stage of the life cycle there are emissions and consumption of resources. The environmental impacts from the entire life cycle of products and services need to be addressed. To do this, life cycle thinking is required.
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By definition, LCA is a technique, which assists in assessing the environmental aspects and potential impacts associated with a product, by:
* Compiling an inventory of relevant inputs and outputs of a product system.
* Evaluating the potential environmental impacts associated with the selected inputs and outputs.
* Interpreting the results of the inventory analysis and impact assessment phases in relation to the objectives of the study (ISO, 1997).
3. SIMPLIFIED LCA
LCA is a holistic and iterative process and needs time to be realized, so, in some situation it is recommended to use a Simplified LCA. The SETAC EUROPE LCA Screening and Streamlining Working Group defines simplified LCA as: Simplified LCA is an application of the LCA methodology for a comprehensive screening assessment i.e. covering the whole life cycle but superficial e.g. using generic data (qualitative and/or quantitative), standard modules for transportation or energy production, followed by a simplified assessment i.e. focusing on the most important environmental aspects and/or potential environmental impacts and/or stages of the life cycle and/or phases of the LCA and a thorough assessment of the reliability of the results.
The aim of simplifying LCA is to provide essentially the same results as a detailed LCA, but with a significant reduction in expenses and time used. Simplification presents a dilemma, however, since it is likely to affect the accuracy and reliability of the results of the LCA. Thus, the primary object of simplification is to identify the areas within the LCA which can be omitted or simplified without significantly compromising the overall result.
Simplification of LCA consists of three stages (Vigon& Jensen, 1995) which are iteratively interlinked:
* Screening: Identifying those parts of the system (life cycle) or of the elementary flows that are either important or have data gaps
* Simplifying: Using the findings of the screening in order to focus further work on the important parts of the system or the elementary flows.
* Assessing reliability: Checking that simplifying does not significantly reduce the reliability of the overall result.
The terms "Screening LCA" and "Streamlined LCA" are often used as synonyms for a simplified LCA. However, a clear distinction should be made. Screening as a part of the simplification procedure can help to identify the parts (or life cycle stages) of a product system that can be left out in a simplified LCA.
In principle, a screening LCA which already has certain parts missing would not be capable of identifying all key issues, as it does not cover the full life cycle or all environmentally important aspects (Curran, 1996). In other words, the screening step in simplified LCA should be comprehensive in coverage, but may be superficial in detail. Screening LCA is for instance used in environmental labeling to identify the environmental "hot spots", i.e. the areas where labeling criteria are assumed to have the greatest effects. Another use of screening LCAs is to identify the processes where emissions of particular interest occur in the life cycle. This procedure can be applied for many other environmental management tools, e.g. risk assessment, to assess whether unwanted effects actually will occur.
4. THE SIMPLIFIED LCA IN A CASE OF A PNEUMATIC CONNECTOR
We exemplify the use of the simplified LCA method in the case of a pneumatic connector and we want to study the environmental impacts of production and utilization for 10 years of 1000 pieces. One connector is composed of nipple, bolt nut and lock nuts.
Among the large numbers of software tools (approximately 37) it was choused SimaPro 7.1 and the BUWAL 250 database. Corresponding of these processes and using the Eco-indicator 99 method, attached of the SimaPro, results the environmental impacts. The Eco-indicators 99 project was commissioned by the Dutch Ministry of Housing, Spatial Planning and the Environment (VROM) in order to update the Eco-indicators 95 methodology. The primary differences of the Eco-indicators 99 method compared to the previous version lie in the characterisation and weighting steps. The effects are allocated to three endpoints categories and these are: human health, ecosystem quality and resources, with units of measurements directly indicating the damages to these endpoints.
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The utilization of a simplified LCA imposes a careful selection of the boundaries and inputs of the system (Blair &Wyckoff 1989). The first step of the method consists in the creation of the life cycle of connectors choosing the materials for which of them. With the help of SimaPro we obtain the environment diagram's impact of the connector assembly. The life cycle of a product can't be discussed without to consider the end life. In the same time it is important to reuse the different components of assembly to diminish the consumption of raw material and energy and the environmental impact. Considering all of this we estimate 10 years long life for the connectors and we can create the life cycle tree. We take nipples and consider that after 10 years 30% of them are recycled and 70% are reutilized and the same for bolt nut-made from the same material. The screw nut, created from a different material, is recycled 60% and reutilized 40%. Now, the life cycle tree can be created (Fig.2). The study was made considered that the pieces are transported with a delivery fan on 100 kilometers. With all of these data, and using Eco-Indicator 99 method the impacts of the connectors' life cycle is shown (Figure 3).
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The simplified LCA can give important information about the environmental impacts of a products or processes and help to choose the right material, technology or transportation way (Arthur, 1989). Very important is to take care of the inputs and outputs considered and the boundary in time and space of the system. Even if a great number of elements can be directly observed and measured in the plants, developing a direct analysis of all elements is not always suitable or possible and the usages of the Simplified LCA is recommended.
Arthur, W. (1989) Competing Technologies, Increasing Returns and Lock-in by Historical Events. The Economic Journal
Blair, P., Wyckoff, A. (1989) The Changing Structure of the U.S. Economy: An Input-Output Analysis. In Frontiers of Input-Output Analysis, eds. R. Miller, K. Polenske, and A. Rose. New York: Oxford University Press.
Curran, M. A. (1996). Environmental life-cycle assessment. New York, USA: McGraw-Hill.
SETAC. (1993). A Conceptual framework for life cycle impact assessment. Pensacola, USA: SETAC
Vigon, B. W., & Jensen, A. A. (1995). Life cycle assessment: data quality and database practitioner survey. Journal of Cleaner Production, 3, 135-141.
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|Publication:||Annals of DAAAM & Proceedings|
|Date:||Jan 1, 2008|
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