Environmental Impact Assessment of the Rebuilt Parts Manufacturing Process

Toya Hanaki･Tatsuki Yamada (Toyama Prefectural University)･Akihiro Hayakawa･Shundai Nezu･Mitsunobu Fujita (NGP)･Masato Inoue (Meiji University)･Takao Mori･Yamada Shuho (Toyama Prefectural University)

Conventional environmental impact assessments of recycled parts have primarily focused on greenhouse gas emissions related to climate change, often lacking a multifaceted analysis of broader environmental impacts. In this study, targeting automotive engines and auxiliary components, the environmental impacts associated with a series of processes ranging from end-of-life vehicle dismantling to remanufacturing were quantitatively evaluated using the LIME2 methodology. Through this comprehensive assessment, the specific environmental impact generated by each individual process was clarified, and the most effective target processes for environmental improvement were successfully identified.

Environmental Impact Assessment for the Remanufacturing of Automotive CVT

Naoki Ichizawa (Waseda University)･Shingo Kodama･Akiko Sawai (Aisin)･Hiroshi Narita (Awquis Japan)･Norihiro Itsubo (Waseda University)

To promote a circular economy, this study comprehensively evaluates the environmental benefits of remanufacturing automotive CVT. By executing life cycle assessments with empirical data gained from detailed process tracking on the manufacturing floor, the research demonstrates that component reuse successfully mitigates both midpoint and endpoint environmental burdens across multiple impact domains while significantly lowering integrated ecological damage costs. Establishing this rigorous quantitative framework through actual industrial practices bridges key information gaps in domestic recycling. Consequently, these findings provide a vital scientific foundation to advance industry standardization and foster the robust expansion of sustainable markets.

Structural Changes in Oligomers and Additives in Polypropylene during Mechanical Recycling

Hirotaka Shioji･Nobuko Taniguchi･Suguru Tamura･Toru Yamanaka (Toray Research Center)･Riku Hashimoto･Ryo Ikegami (Aisin)

Polypropylene (PP) is a major plastic used in automotive applications, and recycling of PP is important. Understanding how PP changes during recycling is also useful for distinguishing it from virgin materials. In this study, changes in PP during material recycling were examined, focusing on the behavior of oligomers, and additives.

Effect of Initial Black Mass Composition on Valuable Metal Recovery in Hydrometallurgical Recycling

Yasuhito Aoki･Hirofumi Moriwaki･Tomohiro Ito･Junpei Yahiro･Hironobu Tsuji (Toray Research Center)

With the increasing practical use of electric vehicles, recycling of lithium-ion batteries (LIBs) has become increasingly important. In this study, two types of black mass with different initial states were prepared and compared. The leaching behavior of Ni, Co, Mn, and Li in a hydrometallurgical process, as well as the composition of insoluble residues, were systematically analyzed. Based on these results, the impact of the initial black mass composition on the recovery efficiency of valuable metals in hydrometallurgical recycling is discussed.

Generalization of Truck Disassembly Process Models for Reused Parts Production and Environmental Impact Assessment

Aoba Nohmura･Kazumasa Kita (Toyama Prefectural University)･Akihiro Hayakawa･Shundai Nezu (NGP)･Yuichi Takenaka (Japan Truck Refine Parts Association)･Mitsunobu Fujita (NGP)･Masato Inoue (Meiji University)･Takao Mori･Shuho Yamada (Toyama Prefectural University)

In automotive recycling, truck disassembly processes vary by facility, and no standardized model exists. For this reason, the calculated environmental impact reductions from reused parts vary depending on the facility. In this study, truck disassembly process models from two different facilities are generalized, and their environmental impacts are presented.

Control Strategies for Extending the Service Life of Repurposed EV Battery Systems

Tenyu Yan･Rika Isawa･Hiroki Nagano (Mazda)･Junichi Ishimaru･Akihiro Ogawa (The Chugoku Electric Power)･Nobuhide Seo･Kazuhiro Murashige･Takashi Utsunomiya･Tomu Fujikawa･Nobutaka Wada (Hiroshima University)

Second-life utilization of automotive batteries is expected to reduce environmental impacts; however, in stationary second-life battery systems composed of multiple batteries, degradation variability causes the battery with the shortest lifetime to constrain overall system longevity. This study develops a power allocation control scheme based on model predictive control (MPC) incorporating degradation models. The proposed method satisfies external power demands while mitigating degradation imbalance and extending system service life. Its effectiveness is demonstrated through experimental validation and simulation.