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PCB007-Aug2024

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78 PCB007 MAGAZINE I AUGUST 2024 dataset generation. e environmental impact of PCB manufacturing varies widely upon the PCB complexity and design choices as well as on the manufacturing processes used. erefore, a parametric lifecycle inventory (LCI) approach is taken to identify the critical design and process parameters that influence the amount of energy used, the materials and their amounts added or removed from the product, the amount of water used, the auxil- iary materials and their amounts used, and the nature and the amount of waste produced. is parametric LCI methodology facilitates data collection by decoupling the process informa- tion from the material parameters and design variability. Experimental Methodology Any system can be considered as a hierar- chical structure of physically and function- ally interconnected system elements. Figure 1 shows such a breakdown for an electronics sys- tem. At the lowest physical hierarchical level, manufactured system elements are situated. ese are elements made directly from pre- processed materials. Examples of such manu- factured system elements are ICs (from semi- conductor wafers), PCBs (from laminates and copper foil), mechanical parts (from sheet or bulk metal), etc. At higher levels, the system elements are assemblies of manufactured ele- ments and/or subassemblies. A graphical representation of the material, water, waste, and energy flows for manufac- tured and assembled system elements is shown in the lower part of Figure 1. In this study, this generic approach is applied to PCB manufac- turing. e LCI model output is intended to be used as inputs for the impact assessment that can be performed by LCA practitioners using any LCA tool. e model can also be used by PCB manufacturers for their environ- mental impact reporting needs. Furthermore, it allows them to identify hotspots in the pro- duction flow for environmental impact reduc- tion purposes. Lifecycle assessment (LCA) is a globally accepted and standardized methodology for determining the environmental impact of a product or manufacturing process 2 . e meth- odology consists of four parts: goal and scope definition, lifecycle inventory (LCI), lifecy- cle impact assessment (LCIA), and interpre- tation. e LCA is structured around a func- tional unit. It defines what is studied and deter- mines product boundaries and the respective inputs and outputs. e potential environmen- tal impacts of the complete product's lifecycle from raw material acquisition through produc- tion, use, end-of-life treatment, recycling and final disposal, is covered in a so-called cradle- to-grave LCA. In some cases, the production phase is considered the most critical or rele- vant, as this is oen the phase the producer has the most influence on. is is called a cradle- to-gate LCA and is quite common in the case of electronics. is paper focuses on the lifecy- cle inventory or data collection aspect of LCA. In 1994, the U.S. Environmental Protec- tion Agency (EPA) initiated a Printed Wiring Board (PWB ) Project within its Design for the Environment (Df E) Program 2 . e goal was to encourage PCB manufacturers to implement cleaner technologies that will improve the environmental performance and competitive- ness of the PCB industry. Two major studies were launched, comparing different technolo- gies for "making holes conductive" and for sur- face finishing 3-4 . For both studies, process data was collected from chemical suppliers and PCB manufacturers. To this day, the respec- tive reports remain the most detailed and com- prehensive publicly available source of data on energy and natural resource consumption for these PCB processes. Numerous LCA databases are available, offered commercially or through open-source efforts 5 . e number of LCA datasets for elec- tronic components within these databases is growing steadily. is paper describes an alternative approach to the challenge of data collection and LCA

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