Simulation and optimization of biomethane production from biogas with the best Carbon Molecular Sieve by Pressure-Swing Adsorption using PSASIM software

This work looked at how well three carbon molecular sieves—Takeda 3A, BF, and KP 407—can separate methane (CH₄) from carbon dioxide (CO₂) using pressure swing adsorption (PSA). By modeling how these gases stick to the materials and how fast they move through them, we found that CO₂ is always adsorbed more easily and quickly than CH₄. Through detailed simulations, we tested how changing factors like bed length, feed speed, cycle time, purge flow, and desorption pressure affects the purity and amount of methane we can recover, as well as how much energy the process uses. Among the three, BF stood out by delivering a good balance of high methane purity (almost 100%), decent recovery rates, and relatively low energy use, making it the most practical choice for upgrading biogas. KP 407 achieved very high purities too, but often sacrificed recovery and used more energy. Takeda 3A couldn’t reach the same purity levels, but it did use less energy, which might make it useful in some specific cases where extremely high purity isn’t needed. By looking at how CO₂ moves through the adsorbent beds, we saw that BF traps and releases CO₂ most effectively, while Takeda 3A struggles to fully clean the bed between cycles. Overall, these findings highlight that choosing the right material and fine-tuning the operating conditions are key to getting the best performance in PSA systems for methane purification.