Optimization of Hydrogen Purification Using a Temperature Swing Adsorption System (TSA) Method in the Natural Gas Processing

Abstract

Hydrogen is an example of renewable and environmentally friendly future energy. Hydrogen as a fuel for emission-free vehicles has attracted much attention recently. The level of hydrogen purity greatly determines its use and economic selling price. Increasing the hydrogen purity can be done in two ways: TSA (Temperature Swing Adsorption) and PSA/VSA (Pressure/Vacuum Swing Adsorption). This study systematically uses the TSA method to optimize the hydrogen purification process. This study aims to obtain a TSA system design based on adsorbents' ability to absorb impurities in hydrogen purification. The designed TSA system also observes the energy-saving operating conditions to produce high-purity hydrogen products. The TSA process consists of six stages, and stages are feed pressurization (FP), adsorption (AD), depressurizing pressure equalization (DPE), depressurization (DP), purge (P), and pressurizing pressure equalization (PPE). The principle of TSA is to use temperature to separate hydrogen from impurities and improve hydrogen purity. All the processes simulated in Aspen Adsorption v11. TSA is carried out by varying temperatures at 278.15 K, 298.15 K, 303.15 K, and 318.15 K. The results of system separation optimization (H2/CO2/CH4/CO/N2 = 0.564/ 0.031/ 0.266 / 0.084/ 0.055) using the TSA method obtained high purity at a temperature of 298.15 K so that it achieved hydrogen purity for the single-bed column of 99.97% and the two-bed column of 99.99%.