(35g) Energy-Effective Design of Steam Methane Reforming with Amine-Based CO2 Capture and Storage (CCS) Process Using Liquefied Natural Gas Cold Energy

Steam methane reforming (SMR) is a traditional process for hydrogen production. Besides the main product hydrogen, SMR also produces CO₂, a green-house gas (GHG), which should be ideally captured and stored after separation from hydrogen. In our study, a novel and cost-effective design for CO₂ capture and storage (CCS) utilizing cold energy of liquefied natural gas (LNG) is carried out using Aspen HYSYS and Aspen EDR. The inlet CO₂ gas stream (85.9mol% CO₂), produced in the SMR process and absorbed by MDEA, is heat-exchanged with a cold LNG stream in a plate-fin heat exchanger. As result, the CO₂ stream is liquefied and stored, while LNG is vaporized. A comparative study has also been undertaken to compare the capital cost of this design to that of the commonly used Linde-Hampson liquefaction process, where CO₂ is liquefied after a sequence of consecutive compressions and expansions. Simulation results with the built-in Economic Analyzer within Aspen HYSYS have shown that for identical inlet and outlet conditions of CO₂ streams, our design would require about 30% less total capital compared to the conventional single looped Linde-Hampson process. If the outlet conditions are allowed to vary, the reduction in total capital compared to the Linde-Hampson process could reach up to 45%.