Batch process design and simulation for the regeneration of MEG, DEG and TEG from a complex refinery waste effluent using E-NRTL method in Aspen Hysys

Abstract

The petroleum industry primarily relies on glycols as hydrate inhibitors. In the petrochemical sectors, one of the key processes is the dehydration of natural gas. Mono-ethylene glycol and tri-ethylene glycol (MEG and TEG) are the most commonly used glycols for dehydration to prevent the corrosion and blockage caused by hydrate development in pipelines. Following this dehydration procedure, a waste glycol combination including organic contaminants such as aromatic hydrocarbons is produced. A novel approach is followed in this research is to develop the modeling and simulation techniques for the regeneration of individual glycol components from the petrochemical waste glycol. The E-NRTL (Electrolyte Non-Random Two-Liquid) property package is used to simulate the process using the simulation tool Aspen Hysys V12.0. The operating parameters, particularly temperature and pressure from the simulation are then validated with an experimental investigation. The outcome from the experiment shows excellent results, with MEG and TEG achieving 99.2% and 99.5% purity respectively, while diethylene glycol (DEG) was not detected in gas chromatography mass spectrometer (GC–-MS). The overall yield of the process was calculated as 99.46%. The sensitivity analysis was conducted to optimize the process to achieve optimum conditions to prevent the system from high pressure drop at 100% column efficiency. This represents a significant advancement towards recycling the waste material into valuable products that can be reused in the process, aligning with Sustainable Development Goal (SDG) 12: Responsible Consumption and Production, and support in achieving the industry targets.