Carbon Footprint Evaluation of Polylactic Acid Production via Process Simulation

Chemical Engineering Department, King Mongkut’s University of Technology North Bangkok, 10800 Bangkok, Thailand

^* Corresponding author: prakorn.k@eng.kmutnb.ac.th

Abstract

This study examines the design process for producing Polylactic Acid (PLA) by optimizing its production using Aspen Plus®. The objective is to enhance the quality and purity of lactide by adjusting various parameters, such as temperature. The research findings have been verified against reported data, revealing that the quantities of essential substances measured at each production stage closely match those reported in existing literatures. A sensitivity analysis reveals that lowering reactor temperatures can reduce energy consumption in both the condenser and reboiler while maintaining the quality of PLA, leading to improved cost efficiency. Additionally, the study evaluates the carbon dioxide emissions resulting from PLA synthesis, which total approximately 656 kg of CO₂ per ton of PLA. Most emissions occur during the oligomerization phase. Therefore, reducing the operational temperature during this phase to 170°C can significantly decrease the carbon footprint of PLA production. This approach helps identify an optimal operational point that maximizes energy savings.