Environmental Footprint of Hot Dip Galvanized Coils and Uncertainty Analysis in Life Cycle Assessment

Abstract

This report consists of two tasks. The first task is to evaluate the carbon footprint and energy use of 1 kg Hot Dip Galvanized Coils, investigate what parameters and processes causing major CO2 and energy use, and explain the differences between this study’s carbon footprint and Eu-Average’s carbon footprint studied by World Steel Association. The other task is to describe motivations for uncertainty analysis, types of uncertainty, methods for uncertainty analysis, and apply the methods to analyze the uncertainties within the first task. Typical thickness of Hot Dip Galvanized Coils ranges between 0.3 and 3 mm and typical width ranges between 600 to 2,100 mm. It is an important product of the studied plant, which can be used for automotive applications, domestic applications, various sections applications, etc. The method used in the first task is LCA and the first task is performed from cradle to gate. LCA is a tool used to quantify the environmental aspects and potential impacts throughout a product, system or functions’ whole life cycle. The methods used in the second task are literature review, scenario analysis, and Monte Carlo Simulation. Well defined uncertainties and methods for uncertainty analysis are gained from literature review. Scenario analysis is a method to choose various datasets/models (or choices/assumptions) to examine their influences on the final results. Monte Carlo Simulation uses a software package to calculate parameter uncertainties. The results of the first task showed the studied plant emits much less CO2 than Eu-Average. This is mainly due to the much greener France Grid Mix supply and the studied plant’s more efficient performance. Moreover, the outcome of the second task indicated that uncertainty analysis could increase the reliability of LCA results. Whatever, uncertainty analysis is very time-consuming.