A Development Study on Environmental Operation Performance Indicators of STN-LCD Industry by Life Cycle Assessment

Autor: PO-WEI YU, 余柏緯
Rok vydání: 2004
Druh dokumentu: 學位論文 ; thesis
Popis: 92
In the display market, the liquid crystal display (LCD) dominates the throughput of flat panel displays (FPD). For Twisted Nematic and Super Twisted Nematic - Liquid Crystal Display (STN-LCD), Taiwan contributes 17.4% of the global share in 2003, which is the second place of the production. Due to the mass production of STN-LCD in Taiwan, the environmental impacts including resource, energy consumption, pollution and wastes, can’t be ignored. In the research, the manufacturing process of a STN-LCD panel was evaluated by using life cycle assessment (LCA). The LCA results will be used as a screen model to identify the hot environmental “spots” of the process, which derives to establish a set of operation performance indicators (OPIs) for this industry. The selected OPIs are also to be the reference of the supervisor administration and improvement of the STN-LCD manufacturing facility. Firstly, a case study was conducted on a representative STN-LCD factory in middle Taiwan. Through gathering information and inventory of materials, energy, pollutants and wastes from the site, a software of life cycle assessment, SimaPro, was then used to analyze the environmental impacts of manufacture process. The OPIs of this plant were initially screened out by LCA results. Then, a three run Delphi questionnaires were performed and reached the consensus. There are 15 Delphi technique’s experts from industry, government and academia, respectively, who finished and revised the OPIs for this study. Based on the final OPIs, an additional questionnaire was developed for site survey. In the research, the total environmental impact of one piece of 1m2 glass panel was 1682mPt. The environmental impact of SiO2/ITO coating process that had 1270mPt was the highest one in ITO process, which contributed 75.14% of total impact scores. The other impact scores were 83.4mPt (4.95%), 74.9mPt (4.44%) and 71.0mPt (4.21%), for the consumption of electricity in STN process, etching and polarizing film process, respectively. A total of 64 indicators and 6 major categories, including consumption of electricity, consumption of water, consumption of chemical substance, air pollution, water pollution and wastes were identified due to the analysis of SimaPro results and the consensus of Delphi Technique’s study. The indicators of the air-pollution category were the most important, followed by those of consumption of chemical substance. The indicators of electricity consumption did not be recognized in the site survey. Furthermore, the line operators thought the measurement of chemical substances indicator was the easiest ones for execution, followed by those of wastes. However, the indicators of electricity consumption were recognized as the most difficult measures. In the execution status, there were most indicators established on Water pollution and Wastes,but with Consumption of electricity being the least one. In fact, the environmental impact of Consumption of electricity was big but industries did not think highly of the section. The overall average score of OPIs was 36.0 with a high standard score being 41.5 and a low standard score being 26.6. The most overall scores of the industries ranged 26~37. It meant that industries still could be promoted on the subject of OPIs.
Databáze: Networked Digital Library of Theses & Dissertations
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