Research topics

Disassemblability Assessment for High Quality Material Recycling

Mechanical Engineering Laboratory has proposed the concept of Ecofactory. Targets of this concept are to reduce and minimize environmental burden over total life cycle of product while keeping products competitiveness of economy and functional performance. In this concept, the restoration system should be integrated with the production system to order to realize resources circulation.
Cooperative efforts between production and restoration are desirable to reduce environmental burden from the life cycle point of view. That is, 'design for disassembly' make reuse and recycling ease, and high quality recovered material can be selected at the design and production stage.
In the early design stage of machining/assembly product, material selection and structure decision are two main tasks. Cooperative consideration between material selection and structure design could be promising solution to realize high quality material recycling.
MEL has proposed material selection strategy by solving trade-off relations between material property and environmental burden. MEL has also focused on product disassemblability. As a quantitative approach, 'Predetermined-Time Standard (PTS)' method has been adopted for estimating necessary time for manual disassembling operation.
As material recycling is a basic option at the product end of life, and high quality recycling is necessary to the resource circulation, a part selection model based on integer linear programming has been introduced. This model is formulated to select parts so as to get maximum weight of the target material recycled while keeping the desired purity rate as constraint. Other constraint such as tramp element, and number of selected parts are also introduced. Parts of a product can be categorized into recycle-group, and non-recycle one by this model. After selecting parts to be recycled, actual disassembling operation could be planned, and necessary time for disassembly can be estimated by the method above mentioned.

　

Contact：　Mitsuro Hattori （hattori@mel.go.jp）