Senior design project: Blue hydrogen production

The demand for hydrogen continues to rise as it becomes more widely used in a variety of industries, including food, petroleum refining, electronics, and transportation1. Company A has requested an in-depth preliminary design of a new blue hydrogen production facility located in the Gulf Coast region to meet the rising demand. Company A defined many of the constraints and specifications for the new production plant, including the production target of 250 MMSCFD (Million Standard Cubic feet per day) of hydrogen on average, which would make our proposal the largest known hydrogen production plant in the world2,3. To achieve the targeted production, our design team has developed a novel facility comprised of eight reactors and two intensive separation units, along with many auxiliary operations. The design was analyzed, optimized, and modeled using a combination of Aspen HYSYS version 14, PolymathPlus, and Aspen Energy Analyzer version 14. The basic process route is as follows: Natural gas is processed via ZnO bed, sent to a pre-reforming reactor, then refined in a set of steam methane reforming reactors before entering the water-gas shift system and finally purifying to 99.99% hydrogen via pressure swing adsorption beds. The decision to supersede the autothermal reforming reactor (ATR) with a steam methane reforming reactor (SMR) was done in the pursuit of efficiency. The isothermal nature of a SMR permits a much greater methane conversion rate of 99% via PolymathPlus, allowing for a much safer overall process due to the reduction of flammable fluids needed to achieve target production. Safety was among our top criteria when designing; as a result, metallurgy, controls, and inherent safety were diligently selected and implemented. Nearly all equipment was designed using 316 stainless steel to avoid corrosion and hydrogen embrittlement. In areas with both corrosion and high temperatures, the team employed nickel alloy. Equipment under incredible heat will be constructed using 310 stainless steel due to its superior heat resistance. Ceramic wool insulation will be installed in the direct-fired heater, the pre-reformer, and the SMRs. Environmental impact was also heavily considered and satisfied using a monoethylamine (MEA) absorption system. The system is designed to be wholly environmentally friendly through the sequestration of MEA yearly and the sale of 100% of the CO2 produced to the beverage industry. Additionally, the facilities’ chosen location in Livingston, Texas allows the plant to employ renewable hydroelectric and solar energy for the operation of the plant. This further reduces scope 2 emissions to a negligible measure. Overall, the plant is designed to capture 100% of all greenhouse gases short of any spontaneous incidents. Over the life of the project, the production plant is predicted to make nearly $8 billion in post-tax, post depreciation revenue with a net present value (NPV) of nearly $700 million. The discounted cash flow rate of return (DCFROR) or yield rate is just under 21%, which places the project close to 6% above the hurdle rate. The yearly operating cost of the entire process comes to just over $760 million, and under these conditions, the payback period is estimated at nearly 9 years. Overall, the economics prove appealing when considering the lack of economic variability identified by the sensitivity analysis