Modeling Of The Life Cycle Inventory Data For Manufacturing Unit Processes

Manufacturing industry is the primary sources of the environmental pollution and resource consumption. At present, the most comprehensive method to evaluate the properties of the resource and environment for a product is the life cycle assessment (LCA). Life cycle inventory analysis, as the most important stage of an LCA, is the process of the compilation and quantification of inputs and outputs for a product throughout its life cycle. In the manufacturing process, the most typical source of the pollution is the manufacture of the electromechanical products. However, the manufacturing processes of electromechanical products are made up by a series of unit processes, so the research on the data of life cycle inventory (LCI) for the unit process is of great significance.Based on the current research status at home and abroad of the inventory data and manufacturing process LCI, this paper analyzes the problems existing in the process of life cycle inventory analysis in detail, and summarizes the basic model, actual analysis processes, and commonly used methods of the inventory analysis. On the analysis basis, this paper discusses the data types of the life cycle inventory in the technological sphere and the environmental sphere.On the basis of determining the types of the inventory data, this paper studies the inputs and outputs characteristics of the environment and resources for unit processes, such as resource consumption, energy consumption and environmental impacts. In addition, this paper also analyzes the effect on the LCI data owning to the choice of the process parameters in the manufacturing process. Furthermore, this paper determines the system analysis boundary and functional unit for a unit process’s study, and discusses two kinds of quantitative methods of the LCI data:screening approach and in-depth approach. The screening approach is a method to obtain inventory data mainly through calculations, which includes the calculations of the energy consumption and the material mass loss; The in-depth approach is a method to obtain inventory data mainly through the measurement of the actual manufacturing process, which includes time research, power research, consumption research and emissions research. This paper mainly studies the screening approach to model inventory data of the life cycle for unit processes. Based on the screening approach, this paper takes the turning, milling and drilling as the research objects and establishes the LCI data models of the corresponding unit process, which involves energy consumption, material loss, and waste liquid and lubricants.Finally, this paper analyzes the two actual cutting examples about turning and drilling respectively, and verifies the feasibility of the data models in the actual processing. According to the screening approach, the inventory of data obtained can find that whether a unit process can meet the demand of green features before processing. If not, engineers can change the processing parameters in accordance with the specific requirements. It can help to reduce the resource consumption and environmental impact, and implement the green manufacturing.