電子機器に使用される鉛はんだと鉛フリーはんだのライフサイクルインベントリ分析

概要

論文の詳細を見る
Life cycle inventory analyses for Pb solder and Pb-free solder in printed wiring boards (PWBs) were conducted to evaluate CO2 emissions during the life cycles of the solders. We assumed that both Pb solder and Pb-free solder were to be either defused by solidification or recycled at the end of their lives. We found that in the life cycles of both solders, the predominant CO2 emissions occurred during the mounting process and waste treatment. In the case of Pb solder, the detoxification process during the waste treatment consumed a large amount of energy; this was avoided by recycling the Pb solder, leading to a reduction in the total life cycle CO2 emissions. The life cycle CO2 emissions for Pb solder were 125 kg-CO2 / Sn-Pb eq. kg in the case where 100% of the Pb solder was recycled at the end of its life. On the other hand, the life cycle CO2 emissions for Pb-free solder were independent of the recycling ratio and were approximately 112 kg-CO2 / Sn-Pb eq. kg. We also investigated how separating the phenol resin from the PWBs during the recycling process affected the life cycle CO2 emissions for the solders. We found that separating phenol resin from waste PWBs could contribute to the reduction of CO2 emissions during the recycling process, but not to the overall reduction of life cycle CO2 emissions for the solders.
社団法人資源・素材学会の論文
2003-02-25