life cycle assessment and optimization model for earth extractive systems, based on multiple criteria decision making problem

Open Access
Author:
Bai, Yu
Graduate Program:
Energy and Mineral Engineering
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
October 29, 2013
Committee Members:
  • Antonio Nieto, Thesis Advisor
  • Luis F Ayala H, Thesis Advisor
  • Jeffrey Brownson, Thesis Advisor
Keywords:
  • Life cycle assessment
  • Optimization
  • Multiple criteria
Abstract:
Life Cycle Assessment (LCA) is a comprehensive method to evaluate all attributes or aspects of potential environmental impacts (and economic benefits) throughout a product’s lifecycle. However, LCA is typically not able to provide effective guidance in the design/production process and forecast potential impacts without obtaining a complete data set needed (e.g. yield, electricity consumed, and CO2 released etc.). Such kind of large data query not only consumes a large amount of time, but limits this method application in new technologies and projects. This is because in practice, it is usually difficult to gain all the specified data in the design phase due to many new technologies or projects that are yet in production with many variables undecided. This report describes a life cycle assessment optimization model (LCAO). This specific model is based on the life cycle inventory (LCI) hybrid method, combining with a modified multiple criteria decision making (MCDM) approach. It requires data but can conduct in the condition of incomplete data set. This helps managers to determine some unknown variables to minimize environmental impact while maximizing economic benefits. In many cases, a number of possibilities for improvements exist and it is not always obvious which one of them results the optimum solution. There could also be more than one optimum solution. In this case, LCAO is also able to find the “best” alternative with multiple and conflicting objectives to provide guidance to managers. It is important to note that LCAO is an iterative process to obtain more and more data determined by the guidance provided by LCAO until the data set is completed. The LCAO model is tested on a crude oil product system as an example.