Shuyuan Geng | MEL Candidate | Dec 14, 2023
Mentor: Matthew Hill ,FortisBC
ABSTRACT
This project investigates the separation of hydrogen from a specific FortisBC Energy Inc. (FEI) Intermediate Pressure pipeline asset based on an anticipated future hydrogen blend of 5 vol%.This study presents an economic and technical evaluation of three hydrogen separation configurations—a two-stage membrane hybrid process, membrane-PSA hybrid process, and one-step Electrochemical Hydrogen Purification and Separation (EHPS)—against the backdrop of current liquid hydrogen procurement practices. Utilizing operational data from the FortisBC natural gas grid and end-user requirements, this project assesses the feasibility of producing fuel cell-grade hydrogen with a focus on cost, efficiency, and operational practicality.
The results indicate that EHPS, an emerging technology, shows promise due to its moderate feed gas consumption, reduced energy requirements, and smaller spatial footprint. Despite it being a developing technology, its favorable energy consumption and payback period positions EHPS as a financially and environmentally sound option. The current liquid hydrogen supply, primarily sourced from out of BC, presents challenges including high transportation costs and potential supply disruptions, suggesting a strategic pivot towards technologies like EHPS could enhance self-sufficiency and support new energy technologies.
INTRODUCTION
Blending hydrogen into natural gas networks is a strategy to enhance system efficiency and reduce carbon emissions, with the existing infrastructure capable of safely transporting hydrogen up to certain concentrations. However, due to varying end-user requirements—some needing high-purity methane and others requiring fuel cell-grade hydrogen—a need arises for effective separation techniques. This project is exploring hydrogen deblending technologies, which serve the dual purpose of catering to specific customer needs while contributing to greenhouse gas (GHG) emission reduction efforts. This endeavor aligns with FortisBC’s Clean Growth Pathway strategy to decarbonize energy sources in British Columbia.
OBJECTIVES
The project’s objectives are to explore and assess hydrogen deblending technologies capable of separating hydrogen from the natural gas grid to serve an end-user’s specific needs, with a focus on producing fuel cell-grade hydrogen that meets the ISO 14687-2019-D purity standards. It entails a comprehensive market analysis of existing separation technologies, particularly evaluating membrane and Pressure Swing Adsorption (PSA) systems, alongside the applicability of the novel Electrochemical Hydrogen Purification and Separation (EHPS) technology. The study is committed to assessing the effectiveness and feasibility of two-stage membrane units, membrane-PSA hybrid processes, and EHPS, to compare the costs, energy consumption, space needed, Ease of Operation and Maintenance, and technical feasibility of these configurations. The goal is to provide a recommendation for a specific fuel cell user, and to determine the optimal separation technology in comparison to the current practices of liquid hydrogen supply and storage.
METHODOLOGY
This project systematically evaluates various hydrogen separation configurations through a multi-faceted approach. It conducts process configurations and feasibility analysis, then quantifies feed gas consumption, pressure drops, and energy consumption for each configuration. This technical assessment is supplemented with a physical layout drawing to estimate the spatial footprint required for each configuration. The project then delves into an economic evaluation, examining both capital and operational costs, and assesses the ease of operation and maintenance for each configuration to ensure practicality. Additionally, it evaluates the greenhouse gas emissions associated with each method. By integrating these analyses, the project compares these hydrogen separation technologies with the current Liquid H2 method to identify the most technologically viable, cost-effective, and environmentally sustainable solution, ensuring operational simplicity and economic rationality.
RESULTS AND DISCUSSION
When the project proposed using the two-stage membrane configuration to produce fuel cell grade hydrogen, a supplier, suggested that achieving fuel cell grade hydrogen purity with membrane separation alone is a cost-prohibitive solution. The supplier team suggested that Pressure Swing Adsorption (PSA) would always be necessary for such applications.
The results and discussion focused on the Membrane and PSA hybrid process , EHPS, and current LH2 configuration camoarison. The Membrane and PSA hybrid process was found to have the highest feed gas consumption, while the EHPS technology was more moderate and the current liquid hydrogen method was the most efficient. Energy-wise, EHPS emerged as the most energy-efficient, contrasting with the high energy consumption of the current liquid hydrogen method. Space requirements analysis showed that the Membrane and PSA hybrid process requires the most area, with EHPS needing less, and the current liquid hydrogen setup being the most space-efficient. Economically, the Membrane and PSA hybrid process is costlier both in terms of initial investment (CAPEX) and ongoing costs (OPEX) compared to the more economical EHPS, which also offers a quicker payback period. In terms of operation and maintenance, the current liquid hydrogen system ranked highest in ease of use, EHPS required more specialized training, and the Membrane and PSA system was the most complex and demanding in operational effort.
CONCLUSION
While the Membrane and PSA hybrid process is mature and robust, the EHPS system stands out as a more cost-effective and space-efficient alternative with a favorable payback period. However, careful consideration should be given to the training of personnel and the potential need for future reconfigurations. The current liquid H2 production method remains a competitive option, particularly where space is limited or where existing infrastructure can be utilized.
REFERENCES
- Pathways for British Columbia to achieve its GHG reduction goals – FORTISBC. (n.d.-e). https://www.cdn.fortisbc.com/libraries/docs/default-source/about-us-documents/guidehouse-report.pdf?sfvrsn=dbb70958_0
- Amin, M., Butt, A. S., Ahmad, J., Lee, C., Azam, S. U., Mannan, H. A., Naveed, A. B., Farooqi, Z. U., Chung, E., & Iqbal, A. (2023). Issues and challenges in Hydrogen Separation Technologies. Energy Reports, 9, 894–911. https://doi.org/10.1016/j.egyr.2022.12.014
- Cavana, M., & Leone, P. (2021). Solar hydrogen from North Africa to Europe through green stream: A simulation-based analysis of blending scenarios and production plant sizing. International Journal of Hydrogen Energy, 46(43), 22618–22637. https://doi.org/10.1016/j.ijhydene.2021.04.065
- Vermaak, L., Neomagus, H. W., & Bessarabov, D. G. (2021). Hydrogen separation and purification from various gas mixtures by means of electrochemical membrane technology in the temperature range 100–160 °C. Membranes, 11(4), 282. https://doi.org/10.3390/membranes11040282.
- Nordio, M., Wassie, S. A., Van Sint Annaland, M., Pacheco Tanaka, D. A., Viviente Sole, J. L., & Gallucci, F. (2020). Techno-economic evaluation on a hybrid technology for low hydrogen concentration separation and purification from natural gas grid. International Journal of Hydrogen Energy. https://doi.org/10.1016/j.ijhydene.2020.05.009
CONTACT DETAILS
Shuyuan Geng
Email: sarahgeng9@gmail.com